Method of the two-stage quick chilling for regeneration of heat and extraction of impurities in the process of conversion of oxygenates

FIELD: regeneration of heat and extraction of impurities.

SUBSTANCE: the invention is pertaining to the method of regeneration of heat and extraction of impurities from the area of the heat-producing reaction in the fluidized flow, conducted for conversion into light olefins of oxygenates present in the flow of the oxygenate (oxygen-containing) raw. raw. The offered method includes the new system of a two-stage quick chilling intended for extraction at the first stage of water from the outgoing from the reactor flow and regeneration of heat of this flow for the purpose, at least, of the partial evaporation of the raw flow due to indirect heat-exchange between the oxygenated raw and the flow of the upper product of the first stage or the flow of recirculation of the first stage. The flow of purification being withdrawn from the first stage, contains the large share of impurities and the high-boiling oxygenates. In the second stage besides conduct extraction of water from the products flow containing light olefins, and produce the flow of the purified water, which requires only the minimum evaporation of the water for production of the water flow of the high degree purification. The method allows to concentrate the impurities in a rather small flow and ensures the significant saving of power and money resources at production of a flow of the vaporous raw guided into the area of realization of the heat-exchange reaction in the fluidized flow.

EFFECT: the invention ensures concentration of the impurities in a rather small flow and the significant saving of power and money at production of the flow of the vaporous raw directed into the area of realization of the heat-exchange reaction in the fluidized flow.

19 cl, 3 tbl, 4 dwg, 5 ex

 

The technical field to which the invention relates.

The present invention relates to a method for extracting impurities and heat recovery exothermic reaction during technological process of converting oxygenates (oxygen-containing compounds) in light olefins. Light olefins are traditionally obtained by steam or catalytic cracking. Due to limited availability and high cost of crude oil cost of obtaining light olefins from such oil sources is steadily increasing. Light olefins are used as raw materials for the production of various chemical products.

Prior art

Research in the field of alternative raw materials for the production of light olefins led to the use of oxygen-containing compounds (oxygenates, such as alcohols and, in particular, to the use of methanol, ethanol and higher alcohols or their derivatives. These alcohols can be produced by fermentation or from synthesis gas. In turn, the synthesis gas can be obtained from natural gas, petroleum liquids and hydrocarbon compounds in the form of coal, recycled (recycling) plastics, municipal waste or any other materials, including organic substances. Thus, the alcohol and alcohol derivatives can provide ways of obtaining the olefin and other related hydrocarbons, based on primary sources, not including oil.

As is known, the process of converting oxygenates in a mixture of hydrocarbons contribute to the molecular sieve, for example, microporous zeolite and no zeolite catalysts, and, in particular, silicoaluminate (SAPO). The technological process of their application, as a rule, can be carried out in the presence of one or more diluents, which may be found in oxygen-containing feedstock in an amount of from 1 to 99 mol.% in the calculation of the total number of moles of the feedstock and diluent supplied in the reaction (or catalytic) zone. In patent documents US 4861938 and US 4677242 And, in particular, special attention is paid to the use of a diluent combined with the feedstock in the reaction zone to maintain the selectivity of the catalyst, sufficient to obtain products from a number of light olefins, particularly ethylene.

The conversion of oxygenates to olefins occurs at relatively high temperature, typically at a temperature of more than 250°S, more preferably 300°C. When the conversion of oxygenates to olefins, the process is strongly exothermic reaction releases a significant amount of heat. Due to the fact that the exhaust from the reactor stream typically has a temperature higher than the temperature of the flow of raw materials, it was suggested many ways the s and usage patterns of the liberated heat of reaction with the to avoid problems when carrying out the process. Developed ways to effectively use the heat of reaction, which is transferred to the flow fraction resulting from the reactor, in order to avoid problems of a technological nature and at the same time reduce the overall cost of the installation during the transformation of the source of oxygenates to light olefins, as well as to minimize the formation of flows of waste substances of the process.

In contrast to the known process of cracking gasoline-ligroin factions held for the production of light olefins, in the present invention light olefins produced by catalytic conversion of oxygenate, in which, in addition, for each mol of the transformed oxygenate get one mole of water. When the conversion of the oxygenate in the presence of molecular sieves made from a substance that does not contain zeolite, such as SAPO-34 or SAPO-17, essentially not formed fraction of heavy hydrocarbons. In addition, the present invention is carried out using a reactor with a fluidized bed, which can lead to the removal of fine particles of catalyst from the reactor with a fluidized bed in a stream emerging from the reactor product. Therefore, resort to schemes with fast cooling (quenching), which allow re tearout heat of reaction, exhaust along with the stream exiting the reactor, and at the same time to minimize the formation of water flows waste substances.

Disclosure of inventions

The present invention provides a method for converting oxygenate to light olefins, which are characterized by a more efficient recovery of the heat content of exhaust from the reactor product streams and improved by removing waste substances, which minimizes the requirements for the overall profitability of the process. According to the proposed method extracted from the reactor fraction is rapidly cooled (quenched) the water flow in the two-stage process conducted for the purpose of facilitating the separation of gaseous hydrocarbons from any small gone catalyst particles, removal of water and heavy by-products such as hydrocarbons With6+. Furthermore, the method according to the present invention avoids the previously unexplored issues that occur when working with well-known systems with a single column of rapid cooling and associated with the formation of corrosive substances, particularly organic acids such as formic and propionic acid. As was found, the exhaust from the reactor stream may contain a small amount of acetic acid, which could be formed in known the technological schemes with fast cooling. According to the present invention resulting from the reactor stream first enters the column first-stage rapid cooling, where it is in contact with relatively pure water stream and a neutralizing agent is introduced from the top of the column rapid cooling, which results in the flow of vaporous hydrocarbon and flow of the cubic product or the flow of waste water. Part of the flow of waste water withdrawn from the bottom of the column rapid cooling, is sent for recycling in the same column at a point above where the column rapid cooling introduces the product stream flowing from the reactor. In accordance with the method corresponding to this invention, the flow of waste water obtained in the column first-stage rapid cooling, is an exhaust stream purification columns, and significantly lower (by consumption) compared to those that could be obtained by using only one column rapid cooling, and in accordance with this invention the flow of the waste water contains heavy organic oxygen-containing compounds and by-products, for example, alcohols and ketones with high molecular weights and components, obtained by neutralization of organic acids, in addition to the carried fine particles of catalyst. Produce is in certain places of the technological scheme of integration of warmth, contained in the stream coming from the reactor, heat flux vapors of hydrocarbon discharged from the column rapid cooling, and the heat contained in the product water output from the lower part of the section of steaming water, provides an improvement of the total amount recycled (and recyclable) heat of reaction process carried out in the reactor and increase the stability of the flow of the whole process.

One of the embodiments of the present invention is a process for the recovery of the heat and remove impurities from the stream exiting the reactor (available from the zone of exothermic reactions carried out in the fluidized bed), used a two-stage rapid cooling. This process includes stages feed stream is pre-heated feedstock containing an oxygenate, to the intermediate capacitor to provide at least partial evaporation of the heated raw material in the process of indirect heat exchange between environments (i.e. through the separation wall recuperative heat exchanger approx. translation.). Partially vaporized raw material is fed into the evaporator to evaporate partially vaporized stream of raw materials to produce a vaporous stream of raw materials. Vaporous stream of raw material is directed to the side input of superheater materials, equipped with the CSO side inlet feed and a side input stream, withdrawn from the reactor for obtaining the parameters of the vapor stream of the raw materials needed for the effective conduct of conversion, through indirect heat exchange with effluent from the reactor flow with getting in the flow of raw materials in the overheated state. Superheated stream of raw material fed into the area of the exothermic reaction in the fluidized bed, and in this area superheated stream of raw materials in contact with the catalyst in the form of solid particles under conditions providing at least partial conversion of oxygenate, which results in the stream exiting the reactor containing light olefins, impurities, water and catalyst particles. Emerging from the reactor flows to the side input superheater feedstock for cooling vapor contained in the stream, below the temperature of overheating. The flow of steam, cooled below the temperature of overheating, served in the column of first stage of two-stage rapid cooling zone containing a column of the first stage and the column of the second stage. The product taken from the top of the column containing light olefins (top product), and the flow of VAT residue of the first stage, containing impurities, catalyst particles and the water, away from the column of the first stage. The first part of the VAT residue of the first stage and neutralizing the return flow in the upper part of the number is NY first stage. At least the second part of the flow of the cubic residue of the first stage output from the process as stream purification columns. Thread the top of the product, or at least part of the flow of the cubic residue of the first stage is directed into the intermediate condenser for cooling the top product or VAT residue by indirect heat exchange with the preheated stream of raw material to produce chilled flow top product or stream VAT residue. The top product flow enters the second stage of the column for the separation of light olefins from the water receiving stream vaporous product comprising light olefins, and purified water. The first part of the flow of treated water back into the upper part of the column of the first stage, the second part of the flow of purified water is cooled in the heat exchanger with the product to receive the cooled stream of purified water that returned to the upper part of the column of the second stage. The third part of the flow of purified water is served in a water Stripping column and get the upper stream of the Stripping column and a stream of highly purified water. The flow of raw material is preheated in the preheater raw materials through indirect heat exchange with a stream of well-purified water to obtain a stream of preheated raw material.

Another example of the implementation of nastoyascheevremya is a technological process, carried out in a two column sudden cooling to extract impurities from the superheated stream leaving the reactor and withdrawn from complete plants for the conversion of oxygenates. This process includes the stages of supply coming out of the reactor superheated stream comprising light olefins, water and organic acids, in the heat exchanger raw materials in/out superheated stream to cool the exit stream of superheated in the reactor, below the temperature of overheating due to indirect heat exchange with the vaporous stream of raw material for producing a stream of cooled below the temperature of overheating. The cooled stream is fed to the first column of the two-stage zone of rapid cooling (quenching), which includes the first column and the second column. Stream is cooled below the temperature of overheating, contacts the top of the first column with neutralized by the flow of water for condensing at least part of the water from the receiving stream VAT residue of the first stage, which includes water and neutralized organic acids, and thread the top product of the first stage containing light olefins and water. The top stream of the first stage enters the second column and contacting it with a stream of cooled purified water to obtain a product stream of light olefins and the Otok purified water. The second part of the flow of purified water is supplied to the Stripping column, in which receive the flow of highly purified water and the top product flow of steam. Top product Stripping columns mixed with the stream of the top product of the first stage and the upper stream of the product of the first stage is cooled before it is fed into the column of the second stage, or the second part of the flow of the purified water feed to the Stripping column and receive a stream of highly purified water and the upper stream of the evaporator of the column, in this part of the thread VAT residue of the first stage is cooled and mixed with a stream of neutralization and the third part of the flow of purified water from the receiving stream is neutralized water. The fourth part of the flow of treated water back into the first stage.

Brief description of drawings

Figure 1 - schematic process flow diagram illustrating a known equivalent.

Figure 2 - schematic diagram of the technological process in accordance with the present invention.

Figure 3 - schematic process flow diagram showing an alternative embodiment of the present invention

4 is a schematic process flow diagram illustrating a preferred embodiment of the invention and a combined process of conversion of oxygenates.

The implementation of the invention/p>

The present invention includes a method of catalytic conversion of a feedstock containing one or more aliphatic heteroskedastic, including alcohols, halides, mercaptans, sulfides, amines, ethers and carbonyl compounds or mixtures thereof, in a hydrocarbon product containing light olefins, for example, olefins With2With3and/or C4. The feedstock is in contact with molecular sieves made from silicoaluminate, at effective conditions for carrying out the process of the production of light olefins. In the method according to the present invention can be used as molecular sieves from silicoaluminate that provide light olefins. The preferred silicoaluminate are described in the patent document US 4,440,871 A. Molecular sieve from silicoaluminate acceptable for use in the present process, described in more detail below.

In the proposed method, the flow of the feedstock contains the oxygenate. Under used in this description the term "oxygenate" means alcohols, ethers and carbonyl compounds (aldehydes, ketones, carboxylic acids, and the like). Oxygen-containing (oxygenate) the feedstock preferably contains from 1 to 10 atoms, and more preferably from 1 to 4 atoms angle of the ode. Acceptable reagents are lower alkanols straight or branched chain and cash equivalents with unsaturated bonds. Typical representatives of suitable chemical compounds, oxygenates include methanol, dimethyl ether, ethanol, diethyl ether, formaldehyde, dimethyl ketone, acetic acid and mixtures thereof.

In accordance with the method corresponding to the present invention, carry out the catalytic conversion of oxygenate feedstock to hydrocarbons, including components of the aliphatic series, for example, methane, ethane, ethylene, propane, propylene, butylene (which do not limit the invention) and limited amounts of other higher aliphatic compounds obtained by contacting the source of aliphatic compounds listed below, with the pre-selected catalyst. For obtaining light olefins, particularly ethylene and propylene, you must have thinner, allowing you to save your selective catalyst. Use as a diluent pair provides advantages from the point of view of the cost of the necessary equipment and thermal efficiency of the process. To improve the efficiency of heat exchange between the feedstock and the effluent from the reactor flow can be used to change the phase state of the odes from liquid to vapor, and to separate the diluent from the product you just need to condense water vapor from the separation of water from hydrocarbons. Identified the required ratio between the concentrations correspond to 1 pray feedstock 0.1-5 moles of water. The method of conversion of oxygenates in accordance with the present invention is preferably conducted in the vapor phase so that the oxygenate feedstock in the vapor contacted in a reaction zone with a catalyst is a molecular sieve in the creation of the conditions of conversion, effective from the point of view of production of olefinic hydrocarbons, i.e. at an effective temperature, pressure, WHSV (average hourly consumption of raw materials) and, if necessary, an effective amount of diluent, corresponding to the process of obtaining olefinic hydrocarbons. For implementing the method required period of time sufficient to obtain the necessary light olefins. The proposed method of conversion of oxygenates successfully implemented in a wide range of pressures, including autogenous pressure. The formation of light olefins product will occur in the pressure range from 0.001 ATM (0,76 Torr) up to 1000 bar (760000 Torr), although the optimal number of target product does not necessarily receive all the above pressure values. The preferred pressure is from 0.01 and the m (of 7.6 Torr) to 100 ATM (76000 Torr). More preferably the pressure is in the range from 1 to 10 atmospheres. Shown here for the proposed method the pressure is given without an inert diluent, if any, that is, represent the partial pressure of the feedstock-related oxygenate compounds and/or their mixtures. The temperature at which it is possible to conduct the process of converting oxygenates may vary within wide limits depending, at least in part, on the catalyst, made in the form of molecular sieves. Usually this method can be carried out at an effective temperature of from 200 to 700°C.

In the process of converting oxygenates according to the invention is preferable that the catalyst had a relatively small pores. Preferably, such catalyst with small pores had essentially homogeneous porous structure, for example, pores with mainly the same size and shape with an effective pore diameter of less than 5 angstroms. A suitable catalyst can be a zeolite molecular sieve materials with a matrix structure.

Not zeolitic molecular sieves include molecular sieves, having a suitable effective pore size, and the material is selected according to the results of experiments chemical compound is and anhydrous basis expressed by the empirical formula

(ELxAlyPz)O2

where EL is a chemical element selected from the group of elements, which includes silicon, magnesium, zinc, iron, cobalt, Nickel, manganese, chromium and a mixture of these elements; x is the mole fraction of the element EL, equal to at least 0,005; y represents a molar fraction of aluminum, equal, at least 0.01, z is the mole fraction of phosphorus equal to, at least 0.01, with x+y+z=1. If EL is a mixture of metals, in this case, the parameter "x" corresponds to the total number present in the mixture of metals. For the preferred example embodiment of the present invention, the EL element is silicon (usually in the form of materials, known as SAPO). The SAPO materials that can be used in this invention are any of the numbers described in patent documents US 4440871 And US 5126308 A, US 191141, including SAPO-34 and SAPO-17.

The preferred catalyst for the conversion of oxygenates may be the catalyst, preferably containing solids in number, largely contributing to the necessary conversion of hydrocarbons. In one aspect, the amount of solid particles selected effective from the point of view of catalysis, and they made at least one material with a matrix structure, preferably selected what about from a group of materials, composed of binder materials, materials - fillers and mixtures of these materials providing the desired property or properties of the catalyst, for example, the desired solubility of the catalyst, the mechanical strength and the like of the properties inherent in the particles of the selected solid material. Such matrix materials are often to some extent original porous structure and may or may not be effective to perform the necessary conversion of hydrocarbons. If the composition of the catalyst included matrix materials, such as binders and/or fillers which are not zeolitic molecular sieve preferably comprise from 1 to 99 wt.%, more preferably from 5 to 90% and even more preferably from 10 to 80% by weight of the total composition.

In the process of chemical transformation (conversion) of oxygenates on the surface of the catalyst precipitates from the reaction Cox. The presence of this coke leads to a decrease in the number of active sites of the catalyst and thereby affects the degree of conversion. In the conversion process part zakoksovanie catalyst withdrawn from the reaction zone, regenerate, to remove at the sulfur portion of the carbonaceous material, and return to the reaction zone, the conversion of oxygenates. Depending on the type of catalyst and features the th ongoing conversion may be desirable to remove the carbon-containing material to a large extent, for example, to content less than 1 wt.% or only partially regenerate the catalyst, for example, to a carbon content of from 2 to 30 wt.%.

A method of converting oxygenates according to the present invention is illustrated below by the example of the technological process of conversion of methanol to olefin (MTO process), which resulted from methanol to produce light olefins, including ethylene and propylene. Before allotment olefins obtained from the MTO reactor (reactor for carrying out the procurement process) these reaction products must be cooled and separated from the water by-product of the conversion, in the column rapid, or rapid cooling (quenching). In the column rapid cooling most of the water is condensed, light hydrocarbons and light oxygenates derived from the top of the column as stream top product and water are removed from the bottom of the column rapid cooling. Water is withdrawn from the column rapid cooling, contains a number of dissolved light hydrocarbons and heavy by-products, including heavy oxygenates including alcohols and ketones having at normal pressure a boiling point greater or the same as water, and which must be removed by the Stripping water contained in the heavy by-products and remove it together with light gases such as water vapor or nitrogen. Sweat is to raw materials, coming to MTO-reactor can be a refined methanol (essentially pure) or crude methanol with water, the content of which is up to 30 wt.%. The specified flow of raw materials before filing in the MTO reactor fluidized bed is heated and evaporated. This requires the expenditure of a significant amount of energy. Therefore, from coming out of the reactor stream you want to extract and regenerate as much as possible (heat) energy and use it for heating and evaporation of flow of the feedstock. However, in column quick cooling water is essentially the only condensation product. Therefore, the working temperature inside the column abrupt cooling close to the temperature of the boiling and condensation of pure water at operating pressure. Although the boiling point of methanol and water differ by about 16° (60°F), the stage of evaporation of the methanol and condensation of water differ according to the current pressure. This difference is caused by the pressure drop (hydraulic losses) when the flow passes through the heat exchangers, the MTO reactor, piping, etc. the Difference in pressure leads to a decrease of the difference between the evaporation temperature of the raw material and the condensation product, which reduces the efficiency of heat transfer. The presence of any quantity of water supplied methanol reduces the curvature of the depending boiling point on pressure and complicates the problem of heat transfer. Since it is difficult to completely evaporate the flow of raw material through only indirectly (through the separation wall) heat exchange between the flow of materials in and out of the reactor by the flow supply of a significant amount of external heat provided by heating the flow of raw water vapor, for complete evaporation of the flow of raw materials before entering into the reaction zone. The reaction zone can be a zone with a fixed bed or fluidized bed, but preferably its implementation fluidized bed.

In the operation of known systems rapid cooling, almost all the water withdrawn from the bottom of the column rapid cooling, contains impurities, and must be subjected to further cleaning before returning to participate in the process, water recirculation flow is cooled by indirect heat exchange with a stream of the feedstock. The present invention significantly reduces the requirement for cleaning VAT residue columns for rapid cooling, provides treated water for the subsequent stage of the process, which reduces the overall requirements of an external service process and reduces the amount of water vapor required for complete evaporation of the flow of raw materials. According to this invention removed from a reactor sweat is to cool below the temperature of overheating and sent to the column of the first stage of rapid cooling. In one embodiment of the invention the vapor stream of hydrocarbons containing light olefins and water, ush with the top of the column first-stage rapid cooling, and providing indirect heat exchange of the steam flow part of the flow of raw materials in the intermediate condenser for cooling and at least partial condensation of hydrocarbon vapors, and part of the heat of reaction is used to heat the flow of the feedstock. Consistently chilled or at least partially condensed vapors of the hydrocarbon served in the separation column of the second stage, or the separator of the product, to further reduce the amount of water in the stream of hydrocarbon vapors. The vapor stream of light olefins is given from the top of the separation column of the second stage, and relatively pure water stream, or the purified water stream is diverted from the lower part of the separation columns of the second stage. Part of the flow of treated water back into the column first-stage rapid cooling, the rest is directed to the area of steaming water, where the flow of purified water removes any remaining oxygenates, for example, dimethyl ether and methanol, and small amounts of light hydrocarbons, such as propane, taken as the upper flow zone steam, and the flow is well purified product water is delaetsa bottom zone of evaporation of the water. The upper stream is withdrawn from zone steam is combined with the hydrocarbon vapors output from the top of the column of the first stage of rapid cooling before carrying out the process of heat exchange with part of the flow of raw materials. In the present invention can be used or the intermediate cooler in the form of the above-mentioned intermediate condenser in indirect heat exchange between the pre-heated stream of raw material and the top of the stream that is output from the column first-stage rapid cooling two-stage quenching, or intercooler, which is an indirect heat exchange between the heated flow of raw materials and the part of the cubic remainder of the column first-stage rapid cooling, which is cooled and returned to the column first-stage rapid cooling in the form of a recirculating flow of the first stage.

Such technological scheme shown in figure 2 and 3 respectively. In both schemes the part of the water contained in the effluent from the reactor stream is condensed and removed from the process from the bottom of the column first-stage rapid cooling as a relatively small stream purification columns containing impurities, catalyst particles and neutralized organic acids. In both schemes the cleaner thread is withdrawn from the column first the stage, is less than 20 wt.% from the total mass of the discharged water, which is the amount of flow of purge and clean, or well-treated, water withdrawn from the Stripping column. Preferably, the cleaner thread is separated from the stream VAT residue columns of the first stage is at least 5 wt.% and less than 15 wt.% from the total mass of the extracted water; and more preferably the cleaner thread is separated from the stream VAT residue columns of the first step contains less than 10 wt.% the total mass of the outgoing water. As it was found in the effluent from the reactor stream, for both technological schemes, presence of organic acids, e.g. acetic acid, formic acid, propanoic acid and the organic acid can be neutralized by introducing the recirculated flow of the first step of neutralizing substances. Thus, any organic acid is neutralized and removed with the clean-up thread in the form of dissolved salts. Due to the removal of the acid in the place of the technological scheme for the rest of consecutive vehicles schema extraction products problems of corrosion and sediment softened already at the starting point of this technological scheme. Preferably, as a neutralizing substance use caustic soda, although there may be used ammonia, and amines, or mixtures thereof.

Figure 2 is a flow diagram with an intermediate capacitor, which involves saving the greatest amount of energy. An unexpected advantage of the circuit shown in figure 2, in which an intermediate cooler is used intermediate the condenser, is that the return of treated water to the column first-stage rapid cooling and cleanup thread split. This separation of threads allows you to independently control the flow of cleaning in the pipeline 25 (2)to provide the required quality of treated water derived from the columns of the second stage or separator product 46 (figure 2). Thus, presented in figure 2 scheme allows the most flexibility in the process for the regulation of the removal of impurities and water from the hydrocarbon product. In addition, the present invention improves the energy efficiency of the whole technological process by indirect heat exchange between the stream exiting the reactor, and the flow of raw materials. The heat exchange is conducted in a heat exchanger, in which the condensation of the steam and boiling of the liquid that provides the maximum value of the resulting heat transfer between the flows in the superheater materials, thereby reducing a significant need for water vapour and providing complete evaporation of the raw materials to podaci reactor.

An alternative method of evaporating part of the raw material provides for the filing of part of the flow of raw materials in the column bog water, the drainage of the upper part of the flow of product from the Stripping column containing vaporous oxygenate, and passing the upper part of the flow of product Stripping columns in the area of the exothermic reaction.

Detailed description of drawings

Figure 1 illustrates the method of rapid cooling (quenching) of the stream exiting the reactor, in accordance with known similar. An example of such method is disclosed in published international application WO 99/55650 A. As shown in figure 1, leaving the reactor, the flow through the pipeline 1 serves in the heat exchanger 11 "raw stream from the reactor to transfer (indirect heat) part of the heat contained in the effluent from the reactor thread, starting materials introduced into the reactor, cooled effluent from the reactor stream, then passing through the pipeline 2. The cooled effluent from the reactor, the flow through the pipeline 2 is supplied to the column 12 sharp cooling water results in the upper stream of olefins in the pipe 3 and the water flow in the pipe 4. Part of the water flow pipe 4 enters the pipe 5, which is shown as a flow of wastewater, and the other part of the water flow from the pipe 4 passes through the pipeline is the wires 6 to the cooler 13 for cooling the recirculation flow, which return line 7 in column 12 sharp cooling water through inlet located above the input stream, extracted from the reactor and supplied through a pipeline 2.

Figure 2 illustrates how the two-stage rapid cooling according to the present invention, in which the effluent from the reactor flow parameters, including temperature in the range from 250 to 550°With, the pipeline 20 is sent to the superheater materials, or Teploobmennik 40 "raw stream from the reactor for cooling the stream exiting the reactor after cooling enters the pipeline 21. The cooled stream through the pipeline 21 is sent to the column 42 of the first stage rapid cooling, with the upper portion 42 and lower portion 42b. In column 42 of the first stage rapid cooling of the above-mentioned cooled stream is connected by pipe 21 to the lower portion 42b of the column first-stage rapid cooling, is in contact with the recirculation flow introduced through line 24', receiving stream top product of the first stage, the exhaust pipeline 26 of the upper part 42 of the column first-stage rapid cooling and containing a smaller amount of water with respect to (enrolled in the column) cooled stream withdrawn from the reactor. The water stream, or the stream bottom balance column is erway stage rapid cooling (water-containing impurities, oxygenates and catalyst particles) through the pipeline 23 is withdrawn from the lower portion 42b of the column 42 of the first stage rapid cooling. At least part of the water flow is diverted from the process circuit by line 23 and then through the pipeline 25 in the form of a water waste stream, or stream cleaning and fed to further processing in the area of water treatment (not shown). Impurities in the stream of cleaning include neutralized acid (in the form of salts of organic compounds). Neutralized acid obtained in the input pipeline 47 effective amount of flow of the neutralizer in the recirculation flow passing through the pipe 24, to neutralize the organic acids to prevent corrosion and sludge in the columns of the first and second stages of rapid cooling. Stream cleanup or waste water stream contains most of the impurities and small particles of the catalyst, concentrated in this small flow treatment, which accounts for from 5 to 10 wt.% from the total mass of the extracted water. The rest of the water flow passing through the pipeline 23, return to the column 42 of the first stage pipeline 24 and 24' in the form of recirculation flow. Thread the top product of the first stage pipeline 26 and 26' are directed to the intermediate condenser 45, where the top is OK the first stage is cooled by indirect heat exchange with getting cooled upstream of the first stage, coming into the pipeline 22. Thread the top of the product from the water Stripping column, which is essentially the whole represents the flow of steam through the conduit 31' away from the Stripping column (not shown) and mixed with the stream of the top product of the first stage, passing in the pipe 26, before entering the upper stream of the first stage pipeline 26 and 26' in the intermediate capacitor 45.

The cooling flow top product of the first stage, the current flowing through the pipeline 26', and the flow in the pipe 20 emerging from the reactor is carried out using previously unused sequence exchangers, which only became possible with the present invention. Accordingly, the flow of the preheated raw material in the pipe 39, containing oxygenate and up to 30 wt.% water serves in the intermediate capacitor 45 from the input of raw materials for the purpose of cooling it flow the top product of the first stage supplied through pipe 26', in the process of indirect heat exchange with a stream of preheated raw material supplied through the pipe 39, to obtain a partially vaporized stream of raw material in the pipe 37 and the cooled stream is the top product of the first stage in the pipeline 22. The partially vaporized stream of raw material in the pipe 37 is supplied to the evaporator raw material 46 to evaporate essentially all of the flow of the raw material and obtain a vaporous stream of raw material in the pipe 37'. Vaporous stream of raw materials by pipeline 37' is supplied to the superheater materials 40. The superheater raw material 40 preferably is a vertical heat exchanger, with a side entry for the flow of raw materials and side input stream exiting the reactor. In the superheater raw material 40 is withdrawn from reactor a stream (a stream of superheated steam in the pipe 20) exchanges heat with the process of indirect heat exchange with a stream of the raw materials that are completely in the vapor supplied through the pipe 37', resulting in the flow temperature of the reactor is reduced below the temperature of the overheating, and the flow of raw material is superheated before it is feed pipe 25 in the area of conversion of oxygenate (not shown).

The cooled stream is the top product of the first stage through line 22 is supplied to the column of the second stage, or the separator product 46, with the upper separation zone 46a and the lower separation zone 46b, with the specified separator product 46 produces a stream of top product of the second stage in the pipeline 27 containing light olefins, and a purified water stream, containing less than 10,000 ppm (wt.) oxygenates, exhaust pipeline 28. Then there is the usual steaming water in the Stripping column, produced for evaporation of oxygenates from a stream of purified water to obtain p the current well of purified water, the stream of highly purified water contains less than 500 ppm (wt.) oxygenates, and more preferably, after the usual bog water, the stream of highly purified water contains from 10 to 100 ppm (wt.) oxygenates. At least part of the flow of treated water back into the column of the first stage pipeline 28 and 29 in the form of a compensating flow columns rapid cooling, and another part of the flow of purified water is drained from the bottom of the separation zone 46b through the pipes 30 and 31 in the final exhaust stream of purified water. The flow of purified water through the conduit 31 enters the column steaming water (not shown), and the flow of the top product from the column steaming water return, as noted above, the pipe 31'. The second part of the flow of purified water through the pipes 30 and 32 are referred to as a first recirculation flow separator 46 to the second heat exchanger 48 for receiving the pipe 34 of the first cooled stream of purified water. The first cooled stream of purified water return in column 46 of the second stage in the insertion, located above the input stream is the top product of the first stage of the pipeline 22 into the upper part of the bottom of the separation zone 46a. From the lower part of the upper zone of the separation-side separator 46 through the pipe 35 is given stream, postupaesh the th in the tertiary heat exchanger 50 for receiving the second separator chilled water flow, or the second recirculation flow, which pipe 36 return in column 46 of the second stage in the upper separation zone 46a. The second heat exchanger 48 may be a product heat exchanger zone separating olefins (not shown), in which the flow of purified water coming from the pipe 32, is cooled by indirect heat exchange with receipt of the first pipe 34 of the cooled flow of purified water.

Figure 3 presents an alternative embodiment of the present invention, according to which the partial evaporation of the heated raw materials are in the intermediate cooler 84, which cools the part of the flow of the cubic remainder of the column first-stage rapid cooling, flowing through the pipe 64, in the process of indirect heat exchange with a spate of raw materials supplied by pipeline 94. According to figure 3 coming out of the reactor the flow through the pipeline 60 enters the superheater materials 80, where effluent from the reactor stream is cooled below the temperature of the overheating and the pipe 61 is fed to the column 82 first-stage rapid cooling. Column 82 first-stage rapid cooling is part of a two-stage rapid cooling zone, which includes the column 82 first-stage rapid cooling and column 86 of the second stage, or the separator of the product. The flow of purified water Truboprovod enters the upper part of the column 82 first-stage rapid cooling and the flow of the upper medium is discharged through pipes 62. Thread the top product in the pipeline 62 contains light olefins and water. Stream VAT residue through line 63 away from the bottom of the column 82 first-stage rapid cooling. Stream VAT residue of the first stage includes impurities, catalyst particles and water. The first part of the thread VAT residue of the first stage is output from the process circuit in the form of a stream of cleaning the pipe 65. The second part of the flow of the cubic residue of the first stage passes through the pipes 63 and 64 to the intermediate cooler 84, which cools the second part of the flow of the cubic residue of the first stage by indirect heat exchange, as described above, by receiving the cooled stream VAT residue of the first stage, passing through the pipe 66. Through line 95 into the pipe 66 is injected neutralizing stream to neutralize impurities consisting of organic acids, such as acetic, formic and propanoic acid, which were unexpectedly detected in the effluent from the reactor thread. As a result of neutralization of organic acids are converted into organic salts. The flow of neutralizing substances selected from the group of substances which includes caustic soda, ammonia and amines. The flow of the chilled VAT residue of the first stage pipeline 66 and the flow of treated water of the second mortar and mix, when it is necessary to obtain in the pipeline 67 flow of purified water that returned to the upper part of the column 82 first-stage rapid cooling. The flow of treated water of the second stage through the pipeline 70 is not mandatory; it is only needed in the case when the amount of heat discharged to the intermediate cooler 84 is insufficient. The stream withdrawn from the top of the column (flow top product pipeline 62, enters the column 86 of the second stage, or the separator of the product, where it is in contact with the cool flow of the purified water supplied by pipeline 74 for further separation of the water flow from the top product of the first step with getting the product stream of light olefins and a stream of purified water discharged through the pipe 68 and the pipe 69, respectively. The first part of the flow of purified water in the pipe 69 return in column rapid cooling of the first stage, as mentioned above, through the pipe 70. The second part of the flow of purified water is sent through pipelines 69, 71 and 73 in the primary heat exchanger 88 of the second stage for receiving the cooled stream of purified water in the pipe 74. The flow of the chilled purified water pipeline 74 return in the lower part of the column of the second stage in the write position, located above the entry in column 86 WTO is the second stage flow top product of the first stage. The exhaust side of the column, the flow through the pipeline 75 is withdrawn from the column 86 of the second stage at a point above the connection point of the recirculation pipe 74, and is supplied to the second heat exchanger 90, the cooling flow, the exhaust side of the column, providing a second stream of cooling water flowing through the pipe 77. The second flow of chilled water through the pipe 77 return in the upper part of the column of the second stage. The third part of the flow of the purified water flowing in the pipe 69, take away through pipes 69, 71 and 72 in the area of steaming water (not shown), where the flow of purified water otparivat with receiving a stream of highly purified water containing less than 500 ppm (wt.) oxygenates. Preferably, the stream of highly purified water contains from 10 to 100 ppm (wt.) oxygenates. In accordance with figure 3 preheated stream of raw materials by pipeline 94 is directed into the intermediate cooler 84 for cooling flow VAT residue of the first stage and at least partial evaporation of the flow of raw materials to produce in the pipe 92 is partially vaporized stream of raw materials. The partially vaporized stream of raw materials by pipeline 92 is sent to the evaporator raw materials 93, in which most of the flow of raw material is evaporated and the flow of raw material into the vapor SOS is the right comes in line 92'. The flow of raw material in the vapor state down side feed in the superheater materials 80, where the flow of raw material is overheating and the pipe 91 can then be sent to the MTO reactor (not shown), while in the superheater 80 stream coming from the reactor and supplied by pipeline 60 is cooled below the temperature of overheating. The stream of the received light olefins pipeline 68 is sent to the separation zone of the product (not shown) to separate the obtained olefinic products. These olefinic products are ethylene, propylene and butylene.

Figure 4 illustrates the joining method according to the present invention, is presented in figure 2, with the complex for the production of propylene, which is included in the installation for the conversion of oxygenates in the product representing light olefins. According to figure 4 the feedstock pipeline 175 enters the heater. 234 with getting warmed raw materials coming into the pipeline 140. The heated flow of raw materials through the pipeline 140 is directed into the intermediate capacitor 208 to the partial evaporation of the flow of raw exhaust in the pipe 141. The partially vaporized stream of raw materials by pipeline 141 is sent to the evaporator raw materials 179, which vaporizes the flow of raw materials significantly with getting vapor stream leaving through line 178. For pipes the wire 178 vaporous stream of raw materials down on the side of the superheater of the raw material 204 to overheating of raw materials, through indirect heat exchange with a stream of output reaction fraction passing through line 143, and the stream of superheated raw materials are sent into the pipe 142. The stream flowing from the reactor through pipe 143, the output from the reaction zone 202 of conversion of oxygenates, which is the catalyst in the fluidized state, recirculating periodically or continuously in a known manner in a regeneration zone 200 to maintain the desired selectivity of the catalyst and the required degree of conversion. In the reaction zone 202 support effective conditions for conducting the conversion of oxygenate to produce in the resulting products including light olefins. The stream flowing from the reactor contains light olefins, water, impurities, unreacted oxygenates and fine particles of a catalyst. In the superheater of the raw material 204 this stream is cooled below the temperature of overheating and receive the stream is not superheated vapor fraction is sent to a pipe 144 in the column 206 of the first-stage rapid cooling two-stage rapid cooling zone, which includes the column 206 of the first-stage rapid cooling and the column of the second stage, or the separator product 210. In the column 206 of the first-stage rapid cooling allocated from the reactor steam stream is cooled below the temperature of the overheating, in contact with the flow of the purified water supplied through a pipeline 149, which is introduced into the upper or lower part of the column 206 of the first-stage rapid cooling. Thread the top of the product through pipe 145 is removed from the column 206 of the first-stage rapid cooling and piping 145 and 151 enters the intermediate capacitor 208 for receiving the cooled stream is the top product of the first stage, entering the pipe 152. In the intermediate capacitor 208 is indirect heat exchange between the pre-heated stream of raw materials supplied by pipeline 140, and the flow of the top product of the column first-stage rapid cooling, exhaust pipeline 151 order partial evaporation of the heated raw material and cooling flow top product of the first stage. Stream VAT residue of the first stage containing the fine particles of catalyst, impurities and water are removed from the column 206 of the first-stage rapid cooling through pipe 146, and part of the VAT residue assign pipeline 148 as stream purification columns. The cleanup thread in the pipeline 148 contains from 5 to 15 wt.% water from the total amount of extracted water, which represents the total amount of water in the clean-up thread and in the flow of highly purified water in the pipe 177, which displays the I at the specified pipeline from the column 214 of steaming water. The rest of the thread VAT residue of the first stage combined with a neutralizing stream introduced through the pipeline 180, and through the pipeline 147 return in the upper part of the column of rapid cooling of the first stage as a recirculation flow rapid cooling. The cooled stream is the top product of the column of the first stage pipeline 152 is sent to the column 210 of the second stage, or the separator of the target product, for the separation of light olefins from water getting in the pipeline 154 flow of vaporous product comprising light olefins and a stream of purified water withdrawn through line 153. The first part of the flow of treated water back into the upper part of the column first-stage rapid cooling through pipes 153 and 149. The second part of the flow of treated water discharged through the pipe 153, sent by pipeline 171 in the heat exchanger 232 for cooling flow of the purified water flowing in the pipe 172. The cooled flow of purified water through the pipe 172 return in the upper part of the pillars 210 of the second stage. The third part of the flow of purified water is sent through pipelines 153 and 153' in the column of steaming water 214 with getting in the steam flow discharged from the top of the evaporator in the pipe 150, and the flow is well purified water flowing in the pipe 170. The flow in the water to high purity by pipeline 170 is sent to the heater. 234 for further cooling of the stream of highly purified water, exhaust after cooling pipeline 177, and at the same time providing a preheating the flow of raw materials supplied to the heater through the pipeline 175, by indirect heat exchange. Thread the top product of the column steaming 214 discharged through pipe 150, is mixed with a stream of the top product of the column 206, the current flowing through the pipeline 145, before entering the United stream of the top product of the first stage in the intermediate capacitor 208 through pipe 151. The content of oxygenates in the flow of highly purified water in the pipe 177 is less than 500 ppm (wt.). When carrying out process a stream of highly purified water can be removed for re-use in any purpose as clean water, or it can be subjected to further processing by a known process, adsorption using molecular sieves, to further reduce the content of oxygenates using the method well known to specialists in this field of technology.

The flow of vaporous product in the pipeline 154 passes the serial number of steps of the processing for obtaining the targeted individual light olefins. Initially, the flow of product in the form of vapour is sent to the compression zone 216 to obtain in the pipelines is e 155 stream of olefins under pressure. The flow of compressed olefin in the pipe 155 is directed to the area of extraction of oxygenates 218 to extract unreacted oxygenates. In the area of 218 extraction of oxygenates can be carried out a process based on the normal absorption, or absorption process using molecular sieves for selective extraction of oxygenates. The flow is essentially exempt from oxygenates, away from the zone of extraction of oxygenates on the pipe 156 and sent to the zone of leaching 220 caustic soda, where the flow is essentially not containing oxygenates, in contact with an aqueous solution of caustic soda to extract carbon dioxide. The stream of light olefins, essentially not containing carbon dioxide, placing the pipe 157 and sent to a drying zone 222 to remove the water. The drying zone 222 is equipped with a known dehydration system using molecular sieve. The flow target is drained of olefin is removed from the drying zone through the pipe 158 and sent in made by the famous image of the area of extraction of light olefins, which are shown in figure 4 as area 224 detonator (acanthodii columns), where the stream containing components having a boiling point lower than that of propylene, or a stream of propylene and heavier compounds away from the zone 224 detonator pipeline 160 and sent further to the extraction of ethylene (n is shown). The flow of propylene and heavier compounds away from the zone of deethanizer and sent by pipeline 164 in the area 228 of depropanizer. In the area of 228 depropanizer the hydrocarbon stream With a3containing propane and propylene is separated from the stream fraction C4+coming in the pipeline 165 having a boiling point higher than that of propane. The flow fraction C4+in the pipeline 165 away for later retrieval butylenes. The hydrocarbon stream With a3sent to the reboiler 230 separating the flow of the propane and propylene, separating the product of propylene of high purity (greater than 95 mole percent propylene)output in the pipeline 166, from the stream of propane directed into the pipe 169. According to the present invention the second part of the flow of the purified water flowing in the pipe 171, used to heat the boiler-separator 230, separating the propane from propylene, or the product of the heat exchanger, thereby cooling the second part of the flow of purified water from getting chilled flow of treated water in pipe 172.

Examples

Example 1

Column a in table 1 reflects the key exchangers process and specific energy consumption for the integrated installation according to well-known counterpart, which uses a column of single-stage rapid cooling and p is otvoditsya 1.2 tons of light olefins in the year by the conversion of methanol feedstock. Key exchangers of this process include the heater of raw materials, in which the raw material is heated in the process of indirect heat exchange with streams otvarennoy waste water; an intermediate cooler in which heat exchange between the heated raw material and recirculating flow VAT residue columns rapid cooling; and a heater of raw materials, in which the heat transfer from flowing out of the reactor thread. Input warmth provide an evaporator that is designed for evaporation of the raw materials before the implementation of the indirect heat exchange of the raw material from flowing out of the reactor by a stream; a boiler for steaming of raw materials, which ensures the supply of heat required for the separation of oxygenates from a stream VAT residue columns rapid cooling; and heat is recovered through the use of the cooler catalyst in the reaction zone. Methanol feedstock contains crude methanol, which includes 82 wt.% methanol and 18 wt.% water. In the processing scheme in accordance with the similar conduct a conversion of the original methanol feedstock in the reaction zone of the fluidized bed using zeolite catalyst SAPO-34 at an operating pressure of from 200 to 350 kPa and a temperature of from 450 to 480°to receive the stream leaving the reactor fractions containing the same amount of ethylene is ropylene. Technological scheme in accordance with the analog requires the total cost of thermal energy 150 GJ (gigajoules) per hour, and for comparison in table 1, the required relative energy costs for this scheme (functioning in a known manner schema with one column rapid cooling) adopted by the amount equal to 1.0.

Example 2

Technological scheme according to well-known analogue, which includes the data shown in column a of table 1, was modified with the inclusion of two-stage scheme of rapid cooling, as described above with reference to figure 3. Column In table 1 reflects the impact of two-stage (two-stage) schema rapid cooling with an intermediate cooler (described above with reference to figure 3) on a separate heat exchangers used in the process, and the desired total energy consumption in an integrated setting for the conversion of oxygenates in relation to the scheme is known analogue, corresponding to Example 1. Although the scheme of the two-stage rapid cooling with an intermediate cooler significantly reduces the amount of wastewater that needs to be clear, it requires increasing the total supply of energy for carrying out the process by 4%. The result is a decrease in the amount of wastewater by 90%, but no Energeticheskaya, stimulating the replacement of a single column on the area of the two-stage rapid cooling.

tr>
Table 1

The comparison of the relative performance of heat exchangers and heat energy consumption
AndIn
The heat exchangerSimilarThe two-stage rapid coolingThe two-stage rapid cooling and an intermediate capacitor
Data on heat exchangers process
The heater raw materials10,910,96
The intermediate cooler (VAT residue columns rapid heating)11,0no
Intermediate capacitornonothere
The superheater materials11,00,99
The energy required to process
The evaporator raw materials11,020,67
The convoy steaming raw materials11,01,03
The total energy, GJ/h149155125
The overall relative supply of energy11,040,83

Example 3

Technological scheme for the well-known analogue reflected in column a And was again modified in accordance with the scheme of two-stage rapid evaporation according to the invention, represented in figure 2. Column in table 1 illustrates the impact of intermediate input capacitor in the circuit two-stage rapid cooling. Enter the intermediate condenser in the flow chart of the two-stage rapid cooling allows for a 90% reduction in the amount of received waste water, and, furthermore, increases the overall energy efficiency of the process. The mapping scheme known analogue (according to data given in column (a) and scheme according to the present invention, is presented in figure 2 (according to data given in column (C), the magnitude of the total energy supply reflects an unexpected advantage in 17% of the scheme deheading (two-stage) rapid cooling with an intermediate capacitor in comparison with analog. It is assumed that casticin is such an advantage is achieved by recovery of the heat flow top product of the column first-stage rapid cooling, used for partial vaporization of the preheated stream of raw materials. Regeneration of this heat reduces the need for external heat supply for complete evaporation of the raw materials before the implementation of the indirect heat exchange between a fully vaporized stream of raw materials and outgoing reactionary faction, and increases the efficiency of heat exchange.

Example 4

The presence of water in the feed stream on the stages of preheating, evaporation and superheating may have a significant effect on total energy input required for carrying out the process. The removal of this associated water will lead to a significant improvement of energy efficiency of the entire complex installations. Table 2 shows that when carrying out the process according to the present invention (see the data in column D) and used as a raw material is essentially pure methanol (99.85% of methanol) energy cost reduced by 50% compared to a known analog - technological scheme with a single column of rapid cooling, data for which are shown in column A. For the implementation of this benefits the dimensions of the intermediate capacitor is selected such that the performance of the intermediate capacitor specified in column C of table 1, increases by more than two R is for. The result achieved by the advantage consisting in limiting the amount of water in the crude methanol (flow of raw materials) to a value of from 0.001 to 30 wt.%, that allows to realize the advantages of the present invention in comparison with the equivalent.

Table 2

Compared with known similar to use case (the present invention) of raw materials in the form of pure methanol
AndD
The heat exchangerSimilarThe two-stage rapid cooling and an intermediate capacitor
Data on heat exchangers process
The heater raw materials10,83
The intermediate cooler (VAT residue columns rapid cooling)1no
Intermediate capacitornothere
The superheater materials10,07
The energy required to process
The evaporator raw materials10,19
The convoy steaming raw materials 10,96
The total energy, GJ/h14973,2
The overall relative supply of energy10,49

Example 5

The use of intermediate capacitor in accordance with the present invention splits the stream purification column, and the purified water is recycled to the column first-stage rapid cooling. The comparison circuits of the present invention (B-D correspond to columns B-D in tables 1 and 2) and the known analogue with a single stage of rapid cooling (A)are illustrated in table 3 with the reflection of the cleanup thread. In table 3 the relative costs expressed in mass flow rate leaving the reactionary faction. Recycling in the column of a single-stage rapid cooling and the column of the first stage of rapid cooling is in the range from 4:1 to 6:1. The cleanup thread, withdrawn from zone two-stage rapid cooling is from 0.04 to 0.05. In cases b, C and D as otvarennoy water can now be increased to the quality of the source water in the boiler, as more high-boiling impurities are removed in the cleanup thread.

Table 3

Comparison of performance and costs (given in the form of mass to which it derived from the reactor stream)
AndInD
Stemming from the reactor stream1110,84
Purified water to the first stage--0,060,34
Recycling in the column rapid cooling6665
The cleanup thread-0,050,050,04
Thread the top of the product to the separator product-0,951,011,15
Pairs of columns of steaming water0,090,100,100,08
Tarenna water0,600,540,540,47
Top product separator0,390,390,390,40

1. Method two-stage rapid cooling for the regeneration of warmth and extracting impurities from a stream flowing from the reactor is discharged from the zone of exothermic reactions carried out in the fluidized bed, including

a) feeding the preheated stream of raw materials containing oxygenate, in between the exact cooler, for at least partial vaporization of the preheated stream of raw material by indirect heat exchange with the receiving stream is partially vaporized raw materials;

b) the feed stream is partially vaporized raw material in the evaporator raw materials for complete evaporation of the partial flow of the vaporized raw materials to produce flow of raw materials in the form of vapour;

c) a vaporous feed stream of raw materials in the superheater materials, with a side of raw inlet and side exhaust stream flowing from the reactor, with the aim of increasing parameters of the vapor flow of raw materials to necessary for carrying out the conversion achieved through indirect heat exchange with effluent from the reactor flow with the receiving stream is superheated raw materials;

d) flow of superheated raw material in the fluidized bed zone of the exothermic reaction in the conditions necessary for carrying out the conversion, and contacting the superheated stream of raw material in this zone, the catalyst particles for at least partial conversion of the oxygenate with getting stemming from the reactor stream containing olefins, impurities, water and catalyst particles;

e) flow resulting from the reactor flow to the side input of superheater materials for cooling resulting from the reactor flow and ensure reduce its temperature below the temperature of overheating;

(f) flow resulting from the reactor stream, cooled below the temperature of the superheat section of the first stage area of the two-stage rapid cooling and ejecting a stream of the upper product containing light olefins, and flow VAT residue of the first stage, containing impurities, particles of a catalyst and water; draining the first part of the thread VAT residue of the first stage from the process as stream cleaning; return the second part of the flow of the cubic residue of the first stage in the upper part of the section of the first stage and the adulteration of neutralizing stream to the second part of the flow of the cubic residue of the first stage;

g) cooling at least part of the specified thread the top of the product or the second part of the flow VAT residue by indirect heat exchange carried out in the intermediate cooler, with a stream of preheated raw materials;

h) flow top product in the section of the second stage zone of the two-stage rapid cooling for the separation of light olefins from water to obtain the product stream in the vapor state, comprising light olefins and a stream of purified water and

i) returning at least part of the flow of purified water into the upper part of the section of the first stage.

2. The method according to claim 1, in which the intermediate cooler is an intermediate condenser providing a cooling gap is the establishment of the upper part of the flow of product through indirect heat exchange with the preheated stream of raw materials, the second part of the flow of purified water is cooled in the grocery exchanger to receive the stream of cooled purified water and a stream of cooled purified water back into the upper part of the section of the second stage.

3. The method according to claim 1, in which the intermediate cooler cools the portion of the stream VAT residue by indirect heat exchange with a stream of the preheated raw material.

4. The method according to any one of claims 1 to 3, in which part of the flow of treated water enters the column steaming water to produce flow top product of the column of steam and water flow of highly purified water, and the flow of raw material is preheated in the preheater raw material by indirect heat exchange with a stream of highly purified water from getting heated flow of raw materials.

5. The method according to claim 4, in which the oxygenate use methanol, higher alcohols, esters, aldehydes, ketones and mixtures thereof, and the light olefins are ethylene, propylene, butylene and mixtures thereof.

6. The method according to claim 5, in which the flow of treated water contains less than 10000 ‰ (wt.) oxygenates, and the flow of highly purified water contains less than 500 ‰ oxygenates.

7. The method according to claim 6, in which the flow of cleaning is less than 15 wt.% of the total flow of the extracted water, including stream cleaning, and the flow of purified water to high purity.

9. The method according to claim 8, in which the flow of raw material contains up to 30% vol. water.

10. The method according to claim 9, including the flow of vaporous product in a separation zone, which is a zone of separation of propane and propylene, containing the boiler, for receiving the flow of the target product is propylene, and the heater includes at least part of the product of the heat exchanger, in which heat is carried out by indirect heat exchange with part of the flow of purified water.



 

Same patents:

FIELD: industrial organic synthesis and petrochemistry.

SUBSTANCE: isoprene is produced via reaction of tert-butyl alcohol with 4,4-dimethyl-1,3-dioxane and/or formaldehyde in one reaction zone, namely upright hollow apparatus with, disposed inside it, shell-and-tube heat exchanger dividing apparatus space into top and bottom parts. Reaction mixture circulates through tubes of this apparatus in liquid-phase mode in presence of aqueous acid catalyst solution, at elevated temperature and pressure exceeding water vapor pressure at the same temperature, using molar excess of tert-butyl alcohol relative to summary formaldehyde equivalent. Reaction products are continuously withdrawn from reaction zone and subjected to condensation. Water phase is extracted with condensed distillate to remove organics, wherefrom isobutylene is recovered and sent to production of tert-butyl alcohol. Hollow apparatus is provided with one or two external circulation tubes connecting top and bottom spaces of apparatus, volume ratio of which is (2-2.5):1, respectively. Diameter of external tubes is at least fivefold greater that that of heat exchanger tubes. Feed is supplied to reaction zone in the form of homogenous mixture, preliminarily prepared in a separate apparatus and preheated to 80-90°C, together with recycle aqueous catalyst solution, the latter having been preliminarily freed of organics and passed at flow rate 15-20 h-1 through cationite. Process is carried out at circulation rate at least 100 h-1.

EFFECT: simplified technology and increased yield of isoprene.

1 dwg, 2 tbl, 2 ex

FIELD: petrochemical processes.

SUBSTANCE: methanol vapors are converted on first catalyst into vapor mixture containing dimethyl ether and first vapor mixture is then converted on form-selective zeolite catalyst into propylene-containing product mixture. Form-selective zeolite catalyst is disposed in the form of charge in at least two in series connected shaft reactors. First portion of dimethyl ether-containing vapor mixture stream is passed to first shaft reactor, wherefrom first intermediate product is withdrawn and routed to second reactor, into which second portion of dimethyl ether-containing vapor mixture stream is supplied. From the last of in series connected reactors, product mixture is discharged and propylene-rich fraction is separated whereas residual materials thus obtained are partly in gaseous form. Al least a part of the latter are recycled into one of shaft reactors.

EFFECT: enhanced process efficiency and increased level of propylene in product mixture.

10 cl, 2 dwg, 1 tbl, 2 ex

FIELD: petroleum processing and petrochemistry.

SUBSTANCE: invention provides catalyst based on pentasil-type zeolites (50-70%) with module SiO2/Al2O3 = 25-100 containing at most 0.11% sodium oxide, 0.1-3% zinc oxide, binder, which catalyst additionally contains 0.1-1% palladium. Catalyst is prepared by modifying indicated zeolites with zinc oxide followed by mixing it binder, modification with zinc being performed by continuous zeolite or binder impregnation technique or with the aid of method comprising ion exchange of zeolite before its being mixed with binder from zinc nitrate aqueous solution in amount ensuring level of zinc oxide in catalyst equal to 0.1-3%, after which palladium is introduced by continuous impregnation technique ensuring level of palladium in catalyst equal to 0.1-1%. Environmentally appropriate gasoline or its components with octane number 92-93 (research method) is obtained from feedstock containing up to 15% dimethyl ether and water steam at molar ratio 2≥H2O/ dimethyl ether≥0 in presence of indicated catalysts at feedstock supply rate 1000-4000 h-1.

EFFECT: reduced tar and coke formation and prolonged lifetime of catalyst.

4 cl, 2 tbl, 12 ex

The invention relates to the field of heterogeneous-catalytic transformations of organic compounds and, more particularly, to catalytic conversion of aliphatic alcohols in the mixture of isoalkanes4-C16

The invention relates to the field of heterogeneous-catalytic transformations of organic compounds and, more particularly, to catalytic transformations of aliphatic alcohols in isoalkanes C8or10

The invention relates to a method of transforming methoxyamine such as methanol or dimethyl ether, olefins, preferably ethylene, by contacting such methoxyamine on a number of fixed catalyst

The invention relates to improved compared with the prior art catalyst to produce liquid hydrocarbons of low molecular weight oxygenated organic compounds comprising crystalline aluminosilicate type pentasil with the value of the molar relationship of silicon oxide to aluminum oxide from 25 to 120, sodium oxide, zinc oxide, oxides of rare earth elements and a binder, where the oxides of rare earth elements it contains the oxides of the following composition, mol.%:

the cerium oxide - 3,0

the oxide of lanthanum - 65,0

the oxide of neodymium - 21,0

the oxide of praseodymium - Rest

moreover, each value of silicon oxide to aluminum oxide in the crystalline aluminosilicate type pentasil corresponds to a certain range of values of the content of sodium oxide, in the following ratio of catalyst components, wt.%:

Crystalline aluminosilicate type pentasil - 63,0-70,0

The sodium oxide - 0,12-0,30

Zinc oxide - 0,5-3,0

The oxide of rare earth elements in the specified composition - 0,1-3,0

Binding - Rest

This catalyst has a higher activity

FIELD: petrochemical processes.

SUBSTANCE: methanol vapors are converted on first catalyst into vapor mixture containing dimethyl ether and first vapor mixture is then converted on form-selective zeolite catalyst into propylene-containing product mixture. Form-selective zeolite catalyst is disposed in the form of charge in at least two in series connected shaft reactors. First portion of dimethyl ether-containing vapor mixture stream is passed to first shaft reactor, wherefrom first intermediate product is withdrawn and routed to second reactor, into which second portion of dimethyl ether-containing vapor mixture stream is supplied. From the last of in series connected reactors, product mixture is discharged and propylene-rich fraction is separated whereas residual materials thus obtained are partly in gaseous form. Al least a part of the latter are recycled into one of shaft reactors.

EFFECT: enhanced process efficiency and increased level of propylene in product mixture.

10 cl, 2 dwg, 1 tbl, 2 ex

The invention relates to the cracking of hydrocarbons, namely the recovery of olefins, in particular alkene from the exhaust gas by catalytic cracking

The invention relates to the field of production of olefinic hydrocarbons obtained from paraffin hydrocarbons by dehydrogenation in a fluidized bed of catalyst and used for the synthesis of isoprene, ethers or other organic products and can be used in the petrochemical industry
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