Method of production of hydrogen-containing gas and regeneration of absorbent used in this method

FIELD: production of hydrogen-containing gas suitable for supply of low-temperature fuel cells in self-contained small-sized electric generators.

SUBSTANCE: hydrogen-containing gas is produced on fixed layer containing the mixture of catalyst of steam conversion of hydrocarbons and regenerated carbon dioxide absorbent including the following stages performed in cyclic succession: A) reaction of steam conversion by passing the gaseous mixture of hydrocarbons and steam through said layer; B) regeneration of carbon dioxide absorbent by passing the regenerating agent through the said layer in direction opposite to direction of delivery of reagents at stage (A). At stage (A), said layer has area at temperature above 700C and area at temperature from 550C to 700C which are so located that reagent are first brought in contact with hotter area of layer and then which area of lower temperature. Regeneration of carbon dioxide absorbent used in production of hydrogen-containing gas is performed by passing the gaseous regenerating agent at content of oxygen no less than 5 vol-% through the said layer. Simultaneously, hydrogen-containing gas at content of hydrogen no less than 40 vol-% is introduced into various areas of the said layer; hydrogen-containing gas goes into exothermic reaction with oxygen of regenerating agent, thus generating the heat for regeneration of absorbent. Proposed method makes it possible to produce hydrogen from hydrocarbon fuel of purity of 98% at content of CO and CO2 lesser than 100 ppm.

EFFECT: facilitated procedure; enhanced efficiency.

8 dwg, 1 ex

 

The invention relates to a method for producing a hydrogen-containing gas with a low content of CO and CO2by catalytic reaction of steam reforming of hydrocarbons in the presence of a regenerated high-temperature absorber of carbon dioxide CO2.

The method of conducting the reaction of steam reforming of hydrocarbons in the presence of the absorber CO2known more. 100 years and was first implemented in 1868 [Tessie du Motay, M., Marechal, M.: Bull. Chim. France 9, 334 (1868)] by passing a mixture of water vapor and methane over a hot calcium oxide. The main process steps are expressed by the following reaction scheme:

Along with catalyst absorber of carbon dioxide solves two tasks: allows you to delete one of the products of the reaction is carbon dioxide, and to shift the equilibrium in the reaction of steam reforming WITH towards the formation of hydrogen. Despite the obvious advantages of this method, the need for periodic regeneration of the absorber in the reverse reaction

makes it economically viable use for large scale synthesis of hydrogen.

However, recently there has been increased interest in portable offline hydrogen generators used to power solid polymer or alkaline toplevelname. In this case, the scheme of regenerated absorber of carbon dioxide has significant advantages over the traditional methods of steam reforming: low sensitivity to the process temperature, resistance to small amounts of sulfur-containing compounds and high purity hydrogen with fewer stages.

For example, Harrison and others [Alejandro Lopez Ortiz and Doug!as P. Harrison. Hydrogen Production Using Sorption-Enhanced Reaction, Ind. Eng. Chem. Res. 2001, 40, 5102-5109. Kwang Bok Yi and Douglas P. Harhson. Low-Pressure Sorption-Enhanced Hydrogen Production, Ind. Eng. Chem. Res. 2005, 44, 1665-1669] was carried out by steam reforming of methane in an isothermal reactor with a fixed bed consisting of a steam reforming catalyst and absorber at a temperature of 450-750°and a pressure of 1 to 15 ATM. The authors have shown that the use of a mixture of industrial catalyst for steam reforming of methane and absorber CO2based on the Cao allows to obtain the hydrogen-containing gas with a hydrogen content of up to 96% vol. and content of CO and CO2less than 100 ppm. The main impurity in the hydrogen is methane at a concentration of 4 vol.% and above, and the methane content decreases with increasing process temperature. On the other hand, conducted by Harrison and others research implies that carrying out steam reforming at lower temperatures reduces the concentration of COx.

In the patent [US 682838, 429/17, 27.01.2004] disclosed is a method of obtaining a hydrogen-containing gas with a content of CO and CO2less than 0.001 vol.%, which consists of stages:

1) steam reforming of hydrocarbons in a fixed bed of a mixture of absorber of carbon dioxide and a catalyst at a temperature of 500-650°C;

2) catalytic mahanirvana residual amounts of CO and CO2in the products of the first stage;

3) regeneration of the absorber of carbon dioxide by method of him blowing heated to temperatures above 650°With water vapor or other gas with a low content of CO2.

In this way the decrease in the concentration of COxcaused, first, by lowering the temperature at stage steam reforming of below 650°secondly, the introduction of an additional stage of mahanirvana. As in the previous work, a substantial portion of hydrocarbon fuel remains unreacted, due to the low activity of the catalysts steam reforming at temperatures below 650°C. Another disadvantage of the proposed scheme is inefficient heat input at the stage of regeneration through heat transfer from the pre-heated gas blown through the fixed layer, the absorber, which requires a high cost of gas recovery and lowers the energy efficiency of the process of producing hydrogen. Figure 1 illustrates the pic is b implementation phase 1) steam reforming in the presence of the absorber and the stage of regeneration of the absorber 3) in accordance with the patent US 6682838, 429/17, 27.01.2004.

The prototype of the present invention is a method of steam reforming of hydrocarbons in the presence of the absorber CO2[US 6103143, 252/373, 15.08.2000]. The process is carried out, passing through the fixed layer consisting of a mixture of absorber CO2and catalyst for steam reforming of hydrocarbons, methane and water vapor at a pressure of 2.5-20 ATM. abs. and a temperature of 300-550°C. After saturation of the absorber CO2it regenerates, flowing countercurrent steam at subatmospheric pressure. As the test showed, in terms of regeneration of the absorber steam at an absolute pressure of 0.5 ATM. and when using a reactor with a length of about 6 m really manage to get the hydrogen content of CO and CO2less than 100 ppm [Waldron W.E., J. R. Hufton, Sircar S. (2001). Production of hydrogen by cyclic sorption enhanced reaction process. A.I.Ch.E. Journal, 47, 1477-1479]. To increase the degree of conversion of methane, the authors proposed to create a temperature gradient in the reactor with a temperature increase from 20 to 100°in the direction of the gaseous mixture of reactants at the stage steam reforming (Figure 2). Figure 2 presents the direction of the temperature gradient in a fixed bed containing a mixture of absorber CO2and catalyst for steam reforming of hydrocarbons, at the stage steam reforming in accordance with the patent US 6103143, 252/373, 15.08.2000. However, the temperature at the stage steam is oversee hydrocarbons (300-550° C) is still insufficient to provide a deep transformation of methane. As a result, the hydrogen content in the resulting hydrogen-containing gas does not exceed 95%. Another problem encountered in the implementation of the proposed method is the use of subatmospheric pressures at the stage of regeneration. Despite the obvious improvement in the dynamics of regeneration of the absorber at a lower pressure, creating a subatmospheric pressure in a compact fuel processor is extremely disadvantageous from the point of view of energy efficiency devices.

Thus, currently there is no way steam reforming of hydrocarbons using absorber CO2suitable for a small Autonomous hydrogen generator and providing a high degree of conversion of the hydrocarbon fuel.

The present invention solves this problem, namely discloses a method of obtaining a hydrogen-containing gas with a hydrogen content of more than 98% by the reaction of steam reforming of hydrocarbons in the presence of the absorber CO2. The content of CO and CO2in the resulting hydrogen does not exceed 100 ppm, and the main impurity is methane in an amount of not more than 2 vol.%. The proposed method is steam reforming of hydrocarbons in a fixed bed consisting of a mixture of catalyst, steam the conversion of hydrocarbons and regenerated absorber of carbon dioxide, is performing a cyclic sequence of stages:

A) the reaction of steam reforming, which consists in passing through the specified layer of the gaseous mixture of reactants consisting of hydrocarbons and water vapor;

B) regenerarii absorber of carbon dioxide passing through the layer specified regenerating agent in a direction opposite to the direction of feed of the mixture of reagents on stage And,

moreover, at the stage A) in a fixed bed must be an area with a temperature above 700°and the region with temperatures ranging from 550 to 700°located in such a way that the incoming reactants are initially in contact with over the heated area of the layer, and then with less hot.

The authors found that non-isothermal mode of carrying out stage A) is favorable to reduce the residual concentration of COxand methane in the produced hydrogen-rich gas. Unlike the prototype of the invention, the reaction conversion and purification from COxcarried out at a temperature above 550°C. Another difference of the invention from the prototype is the direction of the temperature gradient in the absorber layer and the catalyst in stage (A), so that the mixture of the reactants are initially in contact with the hotter part of the layer heated to a temperature of 700°C and above, and then with more cold, with a temperature of 550-700°C.

Another problem to be solved in the invention is improving the efficiency of stage B) regeneration of the absorber CO2. In accordance with the present invention, regeneration of the sorbent is carried out, passing through the fixed layer consisting of a mixture of catalyst for steam reforming of hydrocarbons and absorber of carbon dioxide gaseous regenerating agent with an oxygen content of not less than 5 vol.%, and simultaneously introducing into different areas of the specified layer of the hydrogen-containing gas with a hydrogen content of not less than 40 vol.%, which comes in an exothermic reaction with oxygen regenerating agent and generates the heat required for regeneration of the absorber. To do this with the help provided by the design of the reactor containing the specified layer absorber must be provided by a special device to enter the hydrogen-containing gas. Using multiple input devices of hydrogen located at different distances along the axis of the reactor, at the stage of regeneration B) can be set in the layer of absorber and catalyst required temperature distribution, in particular to ensure the presence of two temperature zones at the stage A).

The maximum degree of the purification of hydrogen is determined by thermodynamics of the steam reforming reaction of hydrocarbons in the presence of the absorber CO2. The authors izopet the deposits were calculated thermodynamically equilibrium composition for the reaction of steam reforming of methane as without absorber, and in the presence of calcium oxide. Figure 3 presents the equilibrium composition of the products of steam reforming of methane with respect to H2O:C=4 and a pressure of 3 ATM. abs. without absorber CO2(solid symbols) and in the presence of Cao (empty symbols). At temperatures below 750°With the presence of the absorber causes a sharp decrease in concentrations of both CO and CO2and prevents the increase of methane concentration in the reaction products. So when the ratio of steam/methane equal to 4, and a pressure of 3 ATM. abs. all of practical interest temperatures thermodynamically equilibrium concentration of methane does not exceed 1.7%.

However, it is well known that the activity of catalysts for steam reforming decreases dramatically with decreasing temperature. So according to [J.R.Rostrup-Nielsen. Catalytic Steam Reforming. In Catalysis. Science and Technology. Ed. J.R.Anderson, M.Boudart. Academie-Verlag. 1984, Vol.5, pp.1-118], the activation energy in the reaction of steam reforming of methane for industrial Nickel catalysts for steam reforming of hydrocarbons is 110 kJ/mol, which corresponds to a drop in activity in 3.5 times at low temperature with 800°700°C. Thus, in case of carrying out a catalytic reaction at a temperature below 700°catalytic activity may not be sufficient to achieve concentrations of methane, close to thermodynamics and equilibrium. Another factor reducing the reaction rate of the conversion of hydrocarbons at low temperatures, is the shift in the equilibrium of reaction 1 in the direction of formation of methane. So when cooled from 800 to 700°equilibrium concentration of methane in the reaction products increases by more than an order of magnitude (Figure 3, curve without absorber).

The analysis points to the need to maintain the temperature above 700°to achieve a high degree of conversion of hydrocarbons on the catalyst steam reforming. On the other hand, in this range of temperatures the vapor pressure of CO2over caso3too high, which prevents the efficient removal of CO2. As follows from figure 3, efficient purification from co and CO2the products of the reaction starts at a temperature of less than 700°when their equilibrium concentration in the presence of the absorber is reduced by more than an order of magnitude. Thus, the joint kinetic and thermodynamic analysis of the process of steam reforming in the presence of the absorber leads to the conclusion about the necessity of the absorber layer and the catalyst in stage (A) two temperature regions, one of which, with temperatures above 700°provides a more complete conversion of hydrocarbons, and the other, with temperatures below 700°C - clean hydrogen-containing gas from CO and CO2.

In the best of the e from the prototype, the authors of the present invention, it was found that different temperature areas shall be located so that the mixture of reagents containing hydrocarbons and water vapor, in contact first with the warmer part of the layer, and then with less hot. Figure 4 shows the temperature distribution at the stage steam reforming in a fixed bed containing a mixture of absorber CO2and catalyst for steam reforming of hydrocarbons in accordance with the present invention. In this case, the mixture of gaseous hydrocarbons and water vapor initially subjected to catalytic steam reforming in a hot area with the formation of CO and CO2. Temperatures above 700°provides a high activity catalyst for steam reforming, so the use of the method of the invention can significantly reduce the catalyst loading compared to the prototype, and use cheap industrial catalysts steam reforming. For example, the desired degree of conversion can provide known in the art catalysts for steam reforming of hydrocarbons containing as an active ingredient Nickel, iron, cobalt, rhodium, ruthenium, palladium, rhenium, osmium, iridium, platinum, gold, or any combination thereof, deposited on a porous substrate made of alumina, aluminate who Alicia, the magnesium aluminate, titanium oxide, zirconium oxide or other thermostable highly porous oxide material, or a substrate of activated carbon [J.R.Rostrup-Nielsen. Catalytic Steam Reforming, In Catalysis. Science and Technology. Ed. J.R.Anderson, M. Boudart. Academie-Verlag. 1984, Vol.5, pp.1-118].

The products of the steam reforming of hydrocarbons, containing significant amounts of CO and CO2comes from high temperature region to a colder region of the layer with a temperature of 550-700°C. This lower temperature favors the reaction (3A) and provides a high degree of purification from CO2using absorbers on the basis of calcium oxide. Reduction of the concentration of CO2also leads to an increase in the depth of steam conversion of CO according to reaction (2), and formed during the reaction of CO2remove the same absorber. The inventors have found that the activity of industrial catalysts for steam reforming of hydrocarbons to the reaction of steam reforming WITH high enough, at temperatures above 550°C. Thus, it is possible to achieve very low concentrations of CO and CO2the produced hydrogen, up to values less than 0.01 vol.% when the temperature of the cold region of the layer to about 550°C.

Although thermodynamic analysis predicts a further increase in depth cleaning from COxwith pangeni the m temperature of the cold region of the layer it was found that below 550°With slow dynamic capacity of the absorber on CO2. The consequence of this is the need for more frequent regeneration of the absorber, which negatively affects the effectiveness of the whole process.

For the practical implementation of the invention requires a way with which you can create the desired temperature distribution at the stage steam reforming. Previously known in this technical field techniques do not allow to achieve the desired effect.

Indeed in patents [US 6103143, 252/373, 15.08.2000; 6682838, 429/17, 27.01.2004] the regeneration of the absorbent perform, feeding countercurrent to the direction of movement of the reactants preheated regenerating agent such as air or water vapor. The cooling regenerating agent due to the endothermic nature of the desorption of CO2and also due to heat loss through the walls of the reactor leads to the fact that the temperature of the layer decreases in the direction of the regenerating agent (Figure 1). Thus, after stage regeneration B) reagents coming to steam reforming stage (A), will first be contacted with a less hot part of the layer, and then more heated (Figure 2).

To overcome this problem, the inventors proposed a method of regeneration of the absorber, based on the separation of the AI heat in the course of an exothermic chemical reaction directly in the absorber layer. To do this, as a regenerating agent use the air cathode gas of the fuel cell or another oxygen-containing gas with an oxygen content of not less than 5 vol.%. The preferred direction of movement of the regenerating agent is countercurrent to the direction of movement of the reagents at the stage A). As progress in regenerating agent layer, it is mixed with hydrogen, the anode gas to the fuel cell or other hydrogen-containing gas with a hydrogen content of not less than 40 vol.%, able to join with oxygen in redox transformation with heat. For these purposes, in a reactor containing a fixed bed absorber and catalyst to provide the input device, the hydrogen-containing gas, having them in different areas of the layer, for example, as shown in Figure 5, where a diagram of the setup used in the example for steam reforming of hydrocarbons in accordance with the present invention.

By controlling the amount of supplied hydrogen-containing gas in each of the input devices, it is possible to regulate the amount of heat produced and the temperature of the corresponding area of the layer in the reactor. It should be noted that the effectiveness of the disclosed invention in the way of heat supply at the stage of regeneration is close to 100%, because with good thermal insulation of the reactor all of videla the mine during the reaction of hydrogen and oxygen heat is used directly in the absorber layer.

The optimum temperature profile for run-stage steam reforming (A) receive, skipping the stage of regeneration B) regenerating agent countercurrent to the direction of movement of the reagents at the stage a) and adjusting the flow of hydrogen containing gas in the layer so that at the end of stage B) the temperature of the layer increased in the direction of the regenerating agent from 550°From input layer to 700°and higher output regenerating agent from the layer. Typically, the desired temperature distribution is formed, giving a greater flow of hydrogen-containing gas input devices located further in the direction of the regenerating agent.

At the end stage of regeneration B) shut off the supply of regenerating agent and hydrogen, increase the pressure in the reactor to a level equal to the pressure stage steam reforming), and passed through the catalyst layer and the absorber a mixture of reagents in the direction opposite to the direction of flow of regenerating agent. Thus, the mixture of the reagents at the stage A) is initially in contact with more hot, having a temperature above 700°C, area of the layer, where the steam reforming reaction of hydrocarbons. As the promotion of the products of steam reforming of hydrocarbons fall into a less hot, having a temperature below 700°With part of the layer, where coverage is walking purification of hydrogen-containing gas from CO and CO 2. After saturation of the absorber of carbon dioxide stage (A) complete, sequentially disabling the supply of reagents and reducing the pressure in the layer up to the pressure stage of regeneration (B). Then the cycle is repeated. The recommended pressure stage steam reforming (A) is from 1 to 20 ATM. abs., and at the stage of regeneration B) from 1 to 2 ATM. abs.

As a raw material for producing hydrogen-containing gas, it is preferable to use an inexpensive fossil, renewable and synthetic hydrocarbons, such as methane, ethane, propane, butane, natural gas, methanol, ethanol, dimethyl ether, gasoline and diesel fuel, and combinations thereof. Before feeding into the reactor in stage (A) hydrocarbon fuel is evaporated, if necessary, and mixed with water vapor in the relationship, in which each carbon atom has from 2 to 6 water molecules. The type of raw materials used can affect the ratio and distribution of the catalyst and absorber layer. So, in the case of steam reforming of ethanol the best results are achieved with homogeneous mixing of the catalyst and absorber, but for other hydrocarbons, for example methane, the preferred loading larger amounts of catalyst in the high temperature area of the layer. The share of the absorber in a mixture with the catalyst should be from 20 to 99.5 wt.% in C the dependence on the type of hydrocarbon and catalyst. The General rule when choosing the ratio of the absorbent/catalyst lies in the fact that the proportion of catalyst should be higher than when using less catalytically active substances (iron, cobalt, Nickel) and the conversion of hard-activated saturated hydrocarbons, such as methane.

As the absorber is proposed to use materials containing in the process of free calcium oxide in an amount of not less than 10 wt.%. Mass fraction of free Cao can be defined by annealing the material at a temperature of 950°in a stream of air for 24 h followed by analysis of one of the known physico-chemical methods.

The invention is illustrated by the following example.

Example.

To implement the methods of the invention was constructed a pilot plant consisting of a reactor 1, a flow control air regeneration 2, pump 3, the evaporator 4, the moisture separator 5, the pressure regulator to 6, block controls the flow of hydrogen 7, an infrared detector for measuring the concentration of CO, CO2CH48, the electromagnetic valve for switching gas flows, electronic data collection systems and the personal computer, through which managed the installation as a whole (Figure 5). Figure 6 shows a diagram of the reactor 1 steam reforming of hydrocarbons in presets is provided absorber CO 2in accordance with the present invention. The reactor is a cylindrical vessel with a volume of 2 liters with four inputs - the conclusions of the gas for supply of reagents (input A), regenerating agent (input B), the hydrogen-containing gas (o) and gases at the stage of regeneration (output G). Also in the reactor were provided additional inputs hydrogen (H1-H4), which is used at the stage of regeneration B) for supplying hydrogen containing gas to the desired area of the layer.

Temperature control is realized by means of thermocouples located along the axis of the reactor. The initial heating of the reactor is performed by means of an electrical heater located on the outer surface of the reactor.

Prior to testing, was charged to the reactor homogeneous mixture of 300 g of industrial Nickel catalyst steam reforming movement of navigation user which is 18 and 1200 g of an absorber of carbon dioxide, containing 99 wt.% The CaO. Both materials are granules of irregular size of 1-2 mm

After heating the reactor to a temperature of 700°With the heater off and test in cyclic mode, starting from the stage steam reforming of hydrocarbons (stage A).

For the implementation of stage a) input B and the output g of the block and with the help of the pump 3 through the evaporator 4 to the input a of the reactor serves a gaseous mixture of water vapor and atrovaginata with a flow rate of 0.6 kg/h and the alcohol content of 28.5 wt.%. Upon reaching the reactor pressure 3 ATM. abs. the pressure regulator to 6 opens and products through the output To arrive at the detector 8. The output of the hydrogen-containing gas is 500 nl/h after 25 min stage A) complete, which stop the flow of the reactants, the reactor pressure equalize with atmospheric and block the input and output of the reactor. After that carry out stage B) regeneration of the absorber, feeding through the input B of the flow regulator 2 the regeneration air with a flow rate of 1500 nl/h and moving through the output g of the mixture of regenerating agent and carbon dioxide. At the same time with the help of block controllers 7 serves hydrogen through the inputs N1-N4, and the flow of hydrogen through the input N1 is not more than 150 nl/h, and after each of the three inputs H2-H4 - not more than 40 nl/h after 30 min stage B) stop, which cut off the flow of regeneration air and hydrogen and repeat step A) to B) in accordance with the described procedure.

After 5 cycles carry out control measurements of the temperature distribution in the layer and the depth of purification obtained in stage A) hydrogenous gas. The obtained data show that after the stage of regeneration B)exercised in accordance with the present invention, the absorber layer and the catalyst contains an area with a temperature above 750°at the entrance of the reagents in reactor area with a temperature below 600° With the output products from the reactor. Thus, application of heat directly in the layer due to the exothermic reaction of hydrogen oxidation is an effective tool to create the desired temperature distribution. Due to the presence on stage A) high - and low-temperature regions, the CO content not exceeding 0.002% vol. for 12 min, and 0.01 vol.% within 16 min after the beginning stage (Fig.7). The concentration of CO2also remains below 0.01 vol.% during the first 18 minutes While the methane content is less than 2 vol.%, and hydrogen is more than 98% throughout stage A) in terms of dry gas. On Fig presents the temperature distribution in the absorber layer and the catalyst at different points in time after the beginning of stage A) steam reforming. As the implementation of stage A) temperature in different zones of the layer are equalized, which adversely affects the purity of hydrogen. So reduce the temperature in the high temperature zone of the layer at the final stage stage) leads to an increase of methane concentration, and the temperature rise in the low-temperature zone leads to an increase in the concentration of CO and CO2Fig 7 presents the content of impurities in the obtained hydrogen, registered at the stage A) during the execution of the example. According to chromatographic analysis, or what and what's impurities, other than CO, CO2CH4and H2O are not present in detectable quantities.

The example demonstrates the possibility of achieving the claimed technical result when using disclosed in the invention of solutions.

1. A method of obtaining a hydrogen-containing gas steam reforming hydrocarbons in a fixed bed consisting of a mixture of catalyst for steam reforming of hydrocarbons and regenerated absorber of carbon dioxide, in which the cyclic sequence

A) conduct a steam reforming reaction, passing through the layer of the gaseous mixture of reactants consisting of hydrocarbons and water vapor;

B) regenerate the absorber of carbon dioxide passing through the layer regenerating agent in a direction opposite to the direction of feed of the mixture of reagents on stage And, characterized in that stage A) in the specified layer has a region with a temperature above 700°and the region with temperatures ranging from 550 to 700°located in such a way that the incoming reactants are initially in contact with over the heated area of the layer, and then with less hot.

2. The method according to claim 1, characterized in that the mass fraction of the absorber of carbon dioxide in a mixture with a catalyst for steam reforming in the specified layer is from 20 d is of 99.5 wt.%.

3. The method according to claim 1, characterized in that as an absorber of carbon dioxide using materials, mass fraction of calcium oxide in which, after ignition is not less than 10 wt.%.

4. The method according to claim 1, characterized in that as a catalyst for steam reforming of hydrocarbons using materials containing as an active ingredient Nickel, iron, cobalt, rhodium, ruthenium, palladium, rhenium, osmium, iridium, platinum, gold, or any combination thereof, deposited on a porous substrate made of alumina, calcium aluminate, magnesium aluminate, titanium oxide, zirconium oxide or other thermostable highly porous oxide material, or a substrate of activated charcoal.

5. The method according to claim 1, characterized in that stage A) is carried out at a pressure from 1 to 20 bar abs., and phase B) at a pressure of from 1 to 2 ATM. abs.

6. The method according to claim 1, characterized in that a hydrocarbon use methane, ethane, propane, butane, natural gas, methanol, ethanol, dimethyl ether, gasoline and diesel fuel, and combinations thereof.

7. Method of regeneration of the absorber of carbon dioxide used in the method of obtaining hydrogen gas by the reaction of steam reforming of hydrocarbons in a fixed bed consisting of a mixture of catalyst for steam reforming of hydrocarbons and absorber di is xida carbon characterized in that through the specified layer pass gaseous regenerating agent with an oxygen content of not less than 5 vol.%, at the same time in different areas of the specified layer introducing the hydrogen-containing gas with a hydrogen content of not less than 40 vol.%, which comes in an exothermic reaction with oxygen regenerating agent and generates the heat required for regeneration of the absorber.

8. The method according to claim 7, characterized in that the regeneration of the absorber create the desired temperature distribution by changing the feed rate of the hydrogen-containing gas in different areas of the fixed layer.

9. The method according to claim 7, characterized in that as a regenerating agent use air or cathode gas of the fuel element.



 

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20 cl, 9 tbl, 9 ex

FIELD: chemical industry; chemical reactor and the method for production of hydrogen.

SUBSTANCE: the invention is pertaining to the power equipment may be used for production of hydrogen both in the stationary plants and on the vehicles. The hydrogen is produced by the hydrolysis (decomposing of water) at its interaction with the granules of the solid reactant (aluminum, silicon, etc.) definitely located inside the chemical reactor. The chemical reactor for production of the hydrogen consists of the cylindrical body with the liquid reactant medium, in which there is the temperature sensor connected with the control unit, and in the upper part of the body there is the union for withdrawal of the gaseous product of the reaction. At that inside of the body the tubular heat exchanger is installed. The tubes of the heat exchanger are arranged at least along two concentric circumferences, spaced from each other and communicate through the collector equipped with the valves for feeding of the heating carrier. Between the tubes of the heat exchanger in the liquid reactant medium there is the annular fire grate, on which the solid reactant granules are placed. The chemical reactor has the vertical spacers inserted between the tubes located on the concentric circumferences shutting the gap between the adjacent tubes. Besides there are the vertical inserts placed between the opposite tubes of the adjacent concentric circumferences shutting the gap between the tubes. At that the indicated spacers and inserts form the zones free from the solid reactant granules, and the valves of the heat carrier feeding are connected through the control unit to the temperature sensors. The method of operation of the chemical reactor for production of hydrogen provides for the liquid reactant feeding in the chemical reactor, withdrawal of the heat and the reaction products from the reaction zone with the help of the heat carrier. Before the liquid reactant feeding into the chemical reactor this reactant is heated up to the temperature ensuring the preset duration of the operational cycle of the reaction, and the heat withdrawal from the chemical reactor with the help of the heat carrier begin at reaching the temperature equal to the temperature of the liquid reactant boiling point with the increase of the heating carrier consumption till the boiling temperature of the liquid reactant will drop to 0.9÷0.8 of the liquid reactant boiling temperature, after that the consumption of the cooling heat-carrier maintain constant till completion of the chemical reaction in the chemical reactor. The inventions allow to increase efficiency of the chemical reactor, to reduce its dimensions and the mass, to improve the fire-explosion safety, to simplify the chemical reactor operation, to reduce its operational costs.

EFFECT: the inventions ensure the increased efficiency of the chemical reactor, the reduced its dimensions and the mass, the improved the fire-explosion safety, the simplified operation of the chemical reactor, the decreased its operational costs.

2 cl, 1 dwg

FIELD: separation and cleaning of synthesis-gas.

SUBSTANCE: proposed section consists of device for partial condensation of synthesis-gas including the following components: heat exchanger A for cooling the synthesis-gas fed to section, separator B connected with heat exchanger A and intended for separation of synthesis-gas into gas fraction consisting mainly of hydrogen and carbon monoxide and liquid fraction consisting mainly of carbon monoxide and methane, evaporator C for further separation of gas fraction fed from separator B into gas fraction consisting mainly of hydrogen and liquid fraction consisting mainly of carbon monoxide, evaporator D where hydrogen absorbed in liquid and remaining liquid containing mainly carbon monoxide are evaporated; this liquid may be directed to distilling tower; section is also provided with one more evaporator E where hydrogen absorbed in liquid fraction of separator B is removed through evaporation; this liquid contains mainly carbon monoxide and methane; liquid may be directed to distilling tower F for separation of gaseous carbon monoxide and obtaining methane from lower part of column. Section is also provided with unit for washing with nitrogen which includes washing column G for separation of admixtures by action of nitrogen from gas fraction of evaporator C and recovery of admixtures as fuel gas. Nitrogen washing unit adjoins the partial condensation device.

EFFECT: enhanced heat exchange; low cost of process.

13 cl, 1 dwg, 1 tbl

FIELD: separation and cleaning of synthesis-gas.

SUBSTANCE: proposed section consists of device for partial condensation of synthesis-gas including the following components: heat exchanger A for cooling the synthesis-gas fed to section, separator B connected with heat exchanger A and intended for separation of synthesis-gas into gas fraction consisting mainly of hydrogen and carbon monoxide and liquid fraction consisting mainly of carbon monoxide and methane, evaporator C for further separation of gas fraction fed from separator B into gas fraction consisting mainly of hydrogen and liquid fraction consisting mainly of carbon monoxide, evaporator D where hydrogen absorbed in liquid and remaining liquid containing mainly carbon monoxide are evaporated; this liquid may be directed to distilling tower; section is also provided with one more evaporator E where hydrogen absorbed in liquid fraction of separator B is removed through evaporation; this liquid contains mainly carbon monoxide and methane; liquid may be directed to distilling tower F for separation of gaseous carbon monoxide and obtaining methane from lower part of column. Section is also provided with unit for washing with nitrogen which includes washing column G for separation of admixtures by action of nitrogen from gas fraction of evaporator C and recovery of admixtures as fuel gas. Nitrogen washing unit adjoins the partial condensation device.

EFFECT: enhanced heat exchange; low cost of process.

13 cl, 1 dwg, 1 tbl

Catalytic reactor // 2296003

FIELD: chemical industry; production of the catalytic reactors.

SUBSTANCE: the invention is pertaining to the chemical industry, in particular, the catalytic reactor, which contains a set of the sheets forming the channels of the streams between them. In each channel of a stream there is the wavy material foils, which surfaces are coated with the catalytic material, except for the places where they contact to the sheets. On each end of the reactor there are the gas-collecting mains for the gaseous mixtures feeding in the channels of the streams. At that the gas-collecting mains are communicating with the adjacent channels separately. The reactor realizes feeding of the various gaseous mixtures in the adjacent channels , which may be under the different pressures, and the corresponding chemical reactions in them are also different. When one of the reactions is endothermic reaction, then the other reaction is exothermal; the heat is transmitted through the sheets separating the adjacent channels from the exothermic reaction to the endothermal reaction. The reactor may be used in the compact-type installation for realization of conversion of the methane with the steam, for production of the necessary heat at the methane catalytic combustion, and also Fisher-Tropsh synthesis, so this general method includes conversion of the methane in the long-chain hydrocarbons. The technical result of the invention is realization of the gaseous phases reactions at the increased pressures and especially for realization of the highly exothermal and endothermal reactions.

EFFECT: the invention ensures realization of the gaseous phases reactions at the heightened pressures and especially for realization of the highly exothermal and endothermal reactions.

9 cl, 6 dwg

FIELD: disproportionation process catalysts.

SUBSTANCE: invention relates to generation of hydrogen through steam conversion of carbon monoxide and development of catalyst for indicated process. Invention provides carbon monoxide conversion catalyst showing high catalytic activity and heat-conductivity and a process of steam conversion of carbon monoxide using indicated catalyst. Catalyst is characterized by heat-conductivity at least 1 W(mK)-1, which enables performing process with low temperature gradient in direction transversal to gas stream direction.

EFFECT: increased catalytic activity and heat-conductivity.

7 cl, 4 dwg, 3 tbl, 10 ex

FIELD: alcoholic beverage industry; food industry; other industries; methods and devices for regeneration of the active charcoal.

SUBSTANCE: the invention is pertaining to the process engineering exploiting the adsorption properties of the active charcoals and may be used for regeneration of the active charcoals after the definite operational cycles at purification of the alcoholic beverage products, the potable water and the waste waters. The active charcoal is heated up to (1-1.2) Tcr and treated with the extractant at the pressure of (1-5) Рcr , whereТcr andРcr - the critical temperature and pressure of the used extractant respectively. At that the direction of the extractant flow is set descending at Re≤20 and - ascending - at Re>20. Regeneration is carried out in the system containing the throttling device, the separator, the compressor or the pump, the withdrawal valve, the adsorber-extractor, which upper end is connected to the inlet of the throttling device, which outlet is connected to the inlet of the separator. The upper outlet of the separator is connected to the inlet of the compressor or the pump. The lower outlet of the compressor is connected to the withdrawal valve. The outlet of the compressor or the pump is connected to the lower end of the adsorber-extractor. In addition between the adsorber-extractor and the throttling device and between the compressor or the pump and the adsorber-extractor there are the installed valves. At that the upper end of the adsorber-extractor through the valve is connected to the outlet of the compressor or the pump and the lower end of the adsorber-extractor through the valve is connected to the inlet of the throttling device. The technical result of the invention is the reduced time of the regeneration of the active charcoal with simultaneous reduction of the power input, the possibility of regeneration of the finely dispersed charcoal and its multiuse.

EFFECT: the invention ensures the reduced time of the regeneration of the active charcoal with simultaneous reduction of the power input, the possibility of regeneration of the finely dispersed charcoal and its multiuse.

2 cl, 1 dwg, 2 tbl, 5 ex

FIELD: sugar industry; production of devices for regeneration of the active granulated charcoal.

SUBSTANCE: the invention is pertaining to the field of sugar industry, in particular, to the device for regeneration of the active granulated charcoal used for purification of the sugar-containing solutions, which consists of: the hopper; the movable and motionless electrodes arranged one inside another with formation of the regeneration area; the tool for the gas withdrawal from the regeneration area and the tool for the unloading еру regenerated charcoal. The tool for withdrawal of the gas from the regeneration area represents the chamber arranged in the lower part of the hopper separated from the cavity of the hopper and the regeneration area by the partition with holes, above which there is the guiding overhang. At that the partition is located with the clearance concerning the motionless electrode for the gases passage and under the electrodes there is the mean for the regenerated charcoal aging and removal of the tail gases consisting of the chamber and the located inside it with formation of the annular clearance perforated tube for the charcoal. The mean for the regenerated charcoal aging consists of the chamber of the rectangular cross section heated from the outer sides by the electrical heaters and containing the channels formed by the inclined plates and one of the camera walls for withdrawal of the gaseous combustion products. The device ensures the increased efficiency of the regeneration process.

EFFECT: the invention ensures the increased efficiency of the regeneration process.

1 dwg

FIELD: petroleum processing and petrochemistry.

SUBSTANCE: process comprises multistep compression of hydrocarbon feedstock pyrolysis gas, separation of water and liquid pyrolysis products, purification and drying of pyrolysis products, sorption drying of liquefied pyrolysis products formed in final pyrolysis, and multistep rectification. Sorption drying of liquefied pyrolysis products is carried out on porous solid sorbent comprising anhydrous calcium chloride, in particular 15-30% CaCl2, 70-85% Al2O3 or 15-30% CaCl2, 50-70% Al2O3, 15-20% SiO2, having loose density at least 0.6 g/cm3 and pore volume at least 0.5 cm3/g at temperature not higher than 40°C and excess pressure 1.9-4.0 MPa. Regeneration of sorbent is effected in flowing gas atmosphere containing at least 80 vol % methane, while cramping temperature to 150°C.

EFFECT: increased economical efficiency of separation allowing longer drying phases and enabling regeneration under milder conditions.

1 dwg, 3 ex

FIELD: sorption technique; regeneration of sorption-catalytic properties of catalysts from inactivated protective means at expired term of storage.

SUBSTANCE: proposed method includes impregnation of copper and chromium with carbon dioxide-ammonium complexes at content of copper of 0.5-5.0%, chromium of 0.1-1.0% and triethylene diamine of 0.5-3.0% followed by heat treatment in fluidized-bed furnace; prior to impregnation, catalysts are neutralized and slightly dried at temperature of t=90-150°C to moisture content of 1-7%; after impregnation, product is aged for 1-2 h and after heat treatment in fluidized-bed furnace, sorbent-catalyst is sieved and fraction with size of grains of 0.5-2.0 mm is selected. Proposed method makes it possible to restore initial activity of sorbents-catalysts at proper homogeneity and stability of this parameter.

EFFECT: enhanced efficiency.

4 rx

FIELD: plant culturing.

SUBSTANCE: invention relates to method for recovery of hydroponics substrates from zeolite. Said zeolite is washed with water, water suspension is prepared from washed substrate, suspension is bubbled with air and treated with ultrasound, water is removed, substrate is washed and treated in magnetic field with induction of 100-200 mTl.

EFFECT: intensified process of substrate recovery.

1 tbl, 1 ex

The invention relates to the regeneration of the solid adsorbent, for example, graphite nozzles for the decomposition of sodium amalgam in the production of chlorine and caustic soda type "graton", heating in the electromagnetic field of the microwave range

The invention relates to cryogenic technique and can be widely used for creating blocks for removal of moisture from in helium liquefaction and refrigeration plants
The invention relates to gas cleaning processes, adsorption - desorption, in particular to the process of purification of acetylene from accompanying impurities of phosphine (PH3) and hydrogen sulfide (H2S) porous absorbers, and can be used in various industries in the process of cleaning gases from similar related impurities
The invention relates to processes of adsorption-desorption

The invention relates to a method of regeneration of the adsorption materials, in particular carbon-carbon composite adsorbents (UUCA), and can be used in wastewater treatment in the production of rocket fuel and neutralizing solutions after neutralization (neutralization) of hardware from the components of rocket fuel

FIELD: veterinary science.

SUBSTANCE: absorbing material contains at least one calcium compound mixed with plant fibers, and dry residue of distillation of mother liquor delivered from enterprises for production of aqueous ammonia soda. Also described is method for utilization of aqueous ammonia solution. Said material is used for absorption of liquid from ground. Described in Specification is litter for animals comprising such a material having good absorbing capacity for absorption of animal's liquid excrements.

EFFECT: improved liquid absorbing capacity and mechanical strength, and reduced adherence to ground during utilization of litter made from such absorbing material.

9 cl

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