Urea producing apparatus

FIELD: equipment of synthesis stage of process for producing urea from ammonia and carbon dioxide.

SUBSTANCE: apparatus includes high-pressure section operating practically at the same pressure values of synthesis reactor and condenser arranged inside said reactor. Condenser includes large number of flat plate like practically rectangular heat exchangers whose long sides are parallel to reactor axis. Each heat exchanger is made of two placed one onto other metallic sheets mutually joined by welding along their perimeter and forming inside heat exchanger preset-width cavity between them. Sheets from which heat exchangers are made are mutually joined by spot welding and they define in cavity of heat exchangers wavy path for fluid flowing. Said path includes mutually connected portions communicated through branch pipes for inlet of flowing heat transfer agent to heat exchangers and outlet of said agent from it. Preferable ducts for distributing flowing heat transfer agent fed to heat exchanger and for collecting outlet heat transfer agent are formed by means of tubes arranged in inner cavity of heat exchanger and secured to its mutually opposite long sides. At least one heat exchanger has internal partition passing from its one side to other opposite side and spaced from said opposite side by some distance for forming in cavity of heat exchanger U-shaped path for flowing heat transfer agent. Said path has descending and raising portions communicated with respective branch pipes passing outside from heat exchanger. Portions of U-shaped path have smoothly increased cross section area.

EFFECT: simplified design of zone for synthesis and condensation of reaction mixture for producing urea at improved efficiency of the whole process.

15 cl, 7 dwg

 

The technical field to which the invention relates.

The present invention relates to so-called "desorption installation for obtaining urea from ammonia and carbon dioxide. The invention relates in particular to a section of high pressure equipment for production of urea of the type specified above, consisting of a reactor for the synthesis of urea and a capacitor or a reactor for the synthesis of urea, desorber and condenser.

The level of technology

By the interaction of ammonia and carbon dioxide under certain pressure and temperature conditions are an aqueous solution containing urea, ammonium carbamate and free ammonia (i.e. ammonia, non-carbamate), and a gaseous mixture containing ammonia, carbon dioxide, water (water vapor) and possibly inert gases.

Upon receipt of urea by the method of desorption containing urea coming from the synthesis reactor an aqueous solution in the corresponding desorber subjected to heat treatment, resulting in the decomposition of the carbamate into ammonia and carbon dioxide with simultaneous desorption (for example, the same carbon dioxide that is fed to the device for producing urea) and the release of solution gas stream containing bógreater part of the unreacted ammonia and carbon dioxide. These gases, together with used to desorb and carbon dioxide then in the corresponding capacitor (known as the carbamate condenser high pressure) again condense into a carbamate, which are returned to the synthesis reactor. Ammonia and carbon dioxide contained in the gaseous state in the effluent from the reactor the reaction mixture, usually transform into ammonium carbamate, in particular absorption in the corresponding capacitor (so-called scrubber) using flow carbamate supplied to the capacitor from the partition selection (regeneration) of urea. Leaving the scrubber flow of carbamate is passed through the condenser of the high-pressure carbamate and return back to the synthesis reactor.

On plants for urea of this type (units desorption type) rector synthesis, desorber, condenser and scrubber are essentially the same (high) pressure and are the most important components of the so-called "section of the high-pressure installation.

On currently known plants for urea synthesis reactor and the condenser of the high-pressure carbamate, and in some cases, scrubber, usually combined in one unit with the General body, designed to work at high pressure. For example, in application WO 00/43358 (PCT/NL/00044)included in the present description by reference, describes apparatus with a vertical case with reactor located between underneath the condenser and above the scrubber, catalysed with capacitor vertical channel, passing through the center of the reactor, and is used to feed into the condenser from the scrubber just formed therein carbamate.

Such presently known equipment for production of urea for all its undoubted advantages possess certain disadvantages.

The first and most significant drawback of plants for urea located in the same housing unit, the condenser and the scrubber is their limited performance increase which is only possible by using the extra number of similar devices, and installation of additional pipelines.

Also used on currently known plants for urea and, in particular, sections of the high pressure condenser and desorber are heat exchangers with beams connected to the opposite pipe grids of tubes, through which the condensable gases and an aqueous solution containing subject to decomposition and desorption of the carbamate.

Design of pipe arrays directly related to the amount fixed in them pipes. The intensity of heat transfer in the condenser and desorber, and thus their performance depend on the number and size of pipes. Consequently, the performance of the entire installation for the doctrine of the urea of a similar type, specifically its section of the high pressure also depends on the number and size of tubes of the tube bundles (and thus the size of the respective tube sheets) capacitor and desorber section. Obviously, because the increase in performance this section of the high pressure requires a corresponding increase in the size (diameter), thickness and weight of pipe arrays.

Obviously, the increase in the size and weight of pipe arrays located inside the high-pressure apparatus, in particular in a conventional reactor for the synthesis of urea or capacitor or desorber, beyond certain limits is not economically viable and technically feasible. Essentially it is the maximum allowable size of pipe arrays and determine the maximum performance of currently known plants for urea.

Another drawback of the use of the tube bundles is associated with problems of distribution of fluid flow in the tubes of the bundle and unreliable cooling or heating each tube flowing in the annular space of the heat exchanger fluid.

In addition, another significant disadvantage of the known reactors used on the plants for urea is too long downtime of the installation required to identify and replace damaged, the example, as a result of corrosion of pipes, as well as the structural complexity and high cost of such reactors.

Summary of the invention

The present invention was used to develop designed to produce urea installation desorption type, design and functional characteristics of the main components of the section of high pressure which would, without limiting the performance of the installation to eliminate the disadvantages inherent in known plants for urea of this type.

This problem is solved according to the invention using the equipment for production of urea of the type specified above, section high pressure which consists of running essentially at the same pressure synthesis reactor, located in the reactor vessel condenser, desorber and scrubber and design features which are provided in the respective claims.

Brief description of drawings

Attached to the description of the drawings shows:

figure 1 is a diagram of a section of a high pressure proposed in the invention of the plants for urea

figure 2 - schematic representation on an enlarged scale reactor for the synthesis of urea setup scheme is shown in figure 1,

figure 3 is an enlarged image in axoneme the series of heat exchanger reactor, shown in figure 2,

figs.4 and 5 other embodiments of the schematically depicted in an enlarged scale respectively a perspective view and front view of the heat exchanger shown in Fig 3,

figure 6 is another embodiment of a schematically depicted in an enlarged scale and shown in figure 2 of the reactor for the synthesis of urea proposed in the invention of the plants for urea and

figure 7 is an enlarged image of a perspective view of a heat exchanger of the reactor shown in Fig.6.

Detailed description of the invention

Shown in figure 1 section of a high pressure intended for obtaining urea from ammonia and carbon dioxide install so-called "desorption type essentially consists of reactor 1 synthesis of desorber 2 and scrubber 3, which operate at the same pressure.

The inner space of the vertical housing 4 of the reactor 1 is divided into a reaction zone 5 and zone 6 of condensation, which is described in detail above, the capacitor 7.

In zone 5 reactions are perforated plates 5A of conventional design, shown in figure 1 by dashed lines.

According to one, not limiting the scope of invention example, upon receipt of urea on the above-mentioned installation is obtained in the reactor 1 an aqueous solution containing urea, carbamate, shumilkin) and free ammonia by pipeline 1A served in desorber 2, in which the bottom of the pipe 2b countercurrent serves carbon dioxide (all or part of the carbon dioxide supplied to the plant).

Coming out of desorber 2 gases, essentially carbon dioxide and ammonia by pipeline 2A is served in the reactor 1 under the condenser 7.

The solution coming out of desorber 2, essentially a solution of urea, ammonium carbamate and free ammonia, pipeline 2C serves (not shown) section allocation urea.

Coming out of the reactor 1 synthesis gases, essentially unreacted ammonia and carbon dioxide and possibly inert gases by pipeline 1b served in the scrubber 3, in which purified from inert gases selected from the scrubber through the pipe 3C, ammonia and carbon dioxide condense the flow of carbamate, which is fed to the scrubber through the pipeline 3b of the partition allocation urea.

Emerging from the scrubber solution of carbamate together with necessary for the reaction of ammonia added to the solution of the carbamate in the 3d pipeline, served by pipeline 3A in the synthesis reactor 1 under the condenser 7.

As shown in figure 2, the cylindrical housing 4 of the reactor 1 is closed from opposite ends of the bottom 8 and top 9 bottom, in the center of the bottom plate 8 is a pipe with a hole 11 that is designed to feed into the reactor leaving JASS is Bera 2 gases (see below) and a mixture of ammonium carbamate selected from the scrubber 3 through the pipe 3A. The upper plate 9 is located in the centre of the pipe with a hole 12 through which from the reactor face formed in the reaction gases, and Luke 13 designed for the maintenance of the reactor.

The capacitor 7 has the shape of a cylindrical ring, the axis of which coincides with the axis of the housing 4. The outer diameter of the condenser slightly smaller than the inner diameter of casing 4, and in the Central hole 14 of the capacitor is removable pipe 15. The pipe 15, the length of which is greater than height of the capacitor 7 has a protruding from the condenser to the outside ends.

To install the condenser 7 in the reactor vessel is round bracket 16 fixed to the inner wall of the housing 4 at a certain distance from the bottom plate 8.

Proposed in the invention, the capacitor 7 is composed of many flat heat exchanger 17, which are evenly spaced on a circle (in this case three) rows around the circumference of the capacitor and each of them (figure 3) is made in the form of a flat box in the form of an elongated rectangle with two opposite long sides 17A, 17A and two opposite short sides 17b, 17b.

In the proposed invention the capacitor 7, the heat exchangers 17 are essentially in radial planes parallelnymi axis of the condenser 7 and, consequently, and case 4) long sides 17A and radial short sides 17b and forms a set consisting of three heat exchangers 17 groups that lie in different radial planes.

Obviously, depending on the specific requirements in each radial plane of the capacitor can be placed from three to two or even one flat heat exchanger, and fill in heat exchangers essentially all the annular space between the Central pipe 15 and the casing 4.

Each heat exchanger 17 (figure 3) consists of two stacked on top of each other and welded along the perimeter of the metal sheets 18, 19, between which is a free space forming the inner cavity 21 of the heat exchanger, through which a fluid coolant.

On opposite sides of each coil are the pipes 22, 23 respectively for the entrance of fluid coolant into the internal cavity 21 of the heat exchanger and exit.

In the first embodiment of the invention, the sheets 18, 19 are made of the heat exchanger are connected to each other by spot welding in many evenly spaced preferably five in each row of points 18a, which give the heat exchanger 17 view of quilts". Such a heat exchanger, in which the leaves are connected by spot welding in a large number of is the number of points 18a, and flowing the coolant flows through the winding path, has a high efficiency of heat transfer.

The inlet pipe 22 of the heat exchangers 17 are connected with located in the housing above the capacitor 7 is bent around the circumference of the distributing pipe 24, which is coming out from the reactor 1 pipe 25 serves (or deduce) the fluid coolant.

Output nozzles 23 of the heat exchangers are connected with located under the capacitor 7 is made of bent along the circumference of the pipe collector 26, pipe 27 connected to the pipe 28 to exit from the reactor 1 (or supply) a fluid carrier.

Under the capacitor 7 is fixed in the usual way in the reactor vessel is made of bent along the circumference of the pipe dispenser 29 gas is connected by a pipe 30 with the corresponding nozzle 30A, which in turn is connected to the pipe 2A, which in the reactor of desorber serves 2 taken from him gases.

Figs.4 and 5 show another variant of the design of the heat exchanger 17, which differs from the above options higher efficiency of heat transfer.

In this embodiment, each heat exchanger 117 is also made of two stacked on top of each other, but United by welding only on the perimeter of the sheet 118, 119 (and therefore, in contrast to the described above with reference to figure 3 th the exchanger does not have the form of quilts"), forming on the opposite long sides 117a of the heat exchanger channels 31 and 32, one of which serves as the distributor, and the other collector 32 fluid coolant. Channels 31 and 32, at least one, preferably through a number of holes 31 a and 32A along one or more of the forming cylinder are communicated with the internal cavity 121 of the heat exchanger and connected to the nozzles 33 and 34 from the outside of the reactor tubes to feed in heat exchanger 117 and selection of it flowing fluid.

Channels 31 and 32 can be performed on the long sides 117a of the heat exchanger 117 or welding the pressed edges of the metal plates 118 and 119, or from welded between sheets of pipes running parallel to the long sides 117a, 117a of the heat exchanger near the edges of its internal cavity 121. Made from pipe bands have come out of the heat exchanger 117 ends, used as the above-mentioned nozzles 33 and 34.

Another distinction made by this variant of the heat exchanger is the location of the nozzles 33 and 34 for entry and exit of fluid coolant on the same short side 117b of the heat exchanger.

In the condenser, shown in figure 2, the short side 117b heat exchangers with the respective nozzles 33 and 34 are located on the upper side of each heat is obmennik 117.

At least part of the heat exchanger 117 proposed in the invention of the capacitor is preferably made according to the scheme shown in figure 5.

In made by this variant heat exchangers 117 internal cavity divided into a number of not reporting directly to each other cameras a formed, for example, welded 121b, parallel short sides 117b of the heat exchanger 117 and respectively perpendicular to the channels 31, 32 of the distributor and collector, which are welded between the metallic plates 118, 119 are made of the heat exchanger. In the cells a, which, depending on the purpose of the heat exchanger can have the same or different widths, are parallel to the channels 31, 32 reflecting plate 122, forming in each cell a spiral trajectory of a fluid coolant.

Each camera a connected, at least one hole 31A with the distributor 31 and at least one aperture 32A with the reservoir 32.

It should be noted that for regulating the pressure drop, and hence a more uniform distribution of fluid coolant in the chambers a holes 31A in the dispenser 31 have different width or diameter which increases in the direction of fluid coolant into the distributor 31.

Figure 6 increased in mA is the headquarters shows a reactor 1 of the synthesis of urea, equipped with condenser 107, which in General is similar to the capacitor 7, as shown in figure 2, but consists of heat exchangers 123, which structurally differ from the heat exchangers described above designs.

Individual items on offer in this embodiment of the invention the reactor 1, which is structurally and functionally no different from those of the reactor shown in figure 2, indicated in the drawings, the same positions and are not re-examined.

The capacitor 107, proposed in a preferred, but not limiting scope of the invention embodiment shown in Fig.6, consists of a set of evenly distributed in the three share a common axis concentric groups of flat hollow heat exchangers 123 rectangular shape. In the condenser 107, shown in Fig.6, the long side 123A of all heat exchangers 123 are parallel to the axis of the housing 4, and the short side 123b, is directed radially towards the axis of the body.

The heat exchangers 123 in this embodiment of the invention, it is preferable to perform the type of heat exchanger, shown in figure 3, i.e. a heat exchanger made of two welded together along the perimeter of sheet metal with an internal cavity 125 for the passage of fluid coolant.

One of the distinguishing features of this variant implementation of the program of the invention is the presence of internal heat exchanger 123 adjacent to one of the short sides C heat exchanger baffles 124, whose length is less than the length of the parallel long sides 123A of the heat exchanger.

Wall 124 preferably by welding two sheets are made of the heat exchanger along the line passing through the middle of one short side s to the other, the opposite short side 123b and ending at some distance from it.

Designed partition 124 divides the inner cavity 125 of the heat exchanger 123 on two adjacent parts 125, 125b, connecting with each other only at the short side 123b, the opposite short side s, which adjoins the partition.

Another distinguishing feature of this variant embodiment of the invention is the existence located at the short side SS heat exchanger, which adjoins the wall 124, the two outside nozzles 126, 127 connected to the two parts 125, 125b internal cavity 125 of the heat exchanger.

In this way the heat exchanger 123 is divided by a partition into two parts 125, 125b internal cavity 125 is U-form shape, and passing through her flowing coolant first descends and then rises.

In the condenser 107, in this embodiment of the invention (6), located in radial planes inside the housing 4 heat exchangers 123 are vertical the major long side 123A and a short horizontal 123b of the lower and upper s hand, located on the upper side of the connecting pipes 126 and 127 and mounted inside the housing 4 of the reactor to the bracket 16 in the manner described above.

Each group of three spaced radial heat exchanger 123 is connected to a pipe 128 to distribute served them in a fluid heat carrier and is made of a pipe manifold 129 which is emerging from the heat exchanger fluid coolant. The pipe 128 is connected to the nozzles 126 of the heat exchangers 123 pipes a and pipe 129 is connected by pipes a with their other nozzles 127.

The pipe 128, through which the heat is supplied fluid, the fluid exits through the wall of the housing 4 of the reactor and is connected with a not shown source of fluid coolant (e.g., boiling water).

The collector 129 similarly, the pipe 128 to supply the heat exchangers fluid coolant exits through the casing wall 4 of the reactor to the outside and connects with a variety of external pipelines.

For output tubes 128 and 129 of the housing 4 of the reactor to the outside are the corresponding connection pipes 130 and 131 located on the body at a certain height close to the height of the upper sides s separate heat exchangers 123 or coincident with it.

The above version has another significant advantage. Used in e is ω embodiment, the heat exchangers 123 is not rigidly connected with other parts of the reactor 1, in particular, with its housing 4, and are free to expand upward in the vertical direction.

Proposed invention is designed to avoid problems of a mechanical nature, related to the different thermal expansion of the heat exchangers and the reactor vessel. Such problems typically arise in cases when flowing inside the heat exchanger fluid coolant is different from the ambient heat exchangers outside the fluid.

7 shows another variant of the design of the heat exchanger 123, which is intended mainly for the use of water as flowing through the heat exchangers, fluid heat carrier. In accordance with this option located in the inner cavity 125 of the heat exchanger wall 124 is inclined at an angle to the adjacent side s heat exchanger 123 (i.e. at an angle to its long sides) and forms the inside of the heat exchanger U-shaped internal cavity 125 from falling, and then rising up areas that have in the direction of flow of fluid coolant gradually increasing cross-sectional area.

The cross-sectional sizes of the heat exchangers 17, 117 and 123 are selected such that each heat exchanger could freely pass through located on the reactor vessel 1 Luke 13.

The advantages of this izobreteny which can eventually be formulated as follows:

- the possibility of establishing a plant for producing urea with significantly greater compared with the known installations of this type of performance, by focusing on what is most important from this point of view, the apparatus, in particular a capacitor, in the proposed invention the installation has no limit performance installation of pipe arrays;

- the lack of problems associated with uneven distribution of the solution of urea and carbamate in the tubes of the tube bundles and unguaranteed efficient heating or cooling pipes flowing outside their fluid environment;

- possibility of eliminating the disadvantages of a mechanical nature, related to the different thermal expansion of the heat exchangers and the reactor;

- the ability to easily and quickly identify and replace damaged plates or groups of heat exchangers;

- easy and fast mounting of the capacitor within the housing, due to the small size of the heat exchangers are selected according to their passage through usually located on the reactor vessel hatch;

- reduced capital costs and the ability to create installation simpler and cheaper in comparison with the known installations of the way.

The invention does not exclude the possibility of making the above options it is implementing various obvious for specialists of changes and improvements, does not distort the meaning and not beyond the scope of the invention defined by its formula.

1. Device for producing urea from ammonia and carbon dioxide containing so-called section high pressure, consisting of an essentially at the same pressure synthesis reactor and located inside the reactor condenser (7, 107), characterized in that the condenser (7, 107) consists of a set of flat plate heat exchangers (17, 117, 123), essentially rectangular shape, the long side (17A, 117a, 123A) which are parallel to the axis of the reactor (1).

2. Installation according to claim 1, characterized in that each heat exchanger (17, 117, 123) is made of two stacked on top of each metal sheets(18, 19; 118, 119), United perimeter welding and forming the inside of the heat exchanger located between the cavity (21, 121, 125) of a certain width.

3. Installation according to claim 2, characterized in that the sheets (18, 19), which made the heat exchangers are connected to each other by welding at specific points (18a), forming in the inner cavity of the heat exchangers tortuous path of flow of the fluid, consisting of interconnected networks of sites connected with located on opposite sides of the heat exchanger (17) nozzles (22, 23) to enter and exit the heat exchanger (17) fluid coolant

4. Installation according to claim 3, characterized in that the point (18a) welding are organized into groups, each of which consists of five points.

5. Installation according to claim 3, characterized in that the input and output connections (22, 23) all heat exchangers (17) connected with the pipes (24, 26), designed for distribution of fluid coolant supplied to the heat exchangers, respectively, for collecting fluid coolant exiting the heat exchangers.

6. Installation according to claim 2, characterized in that it is located on two opposite sides (117a) of each heat exchanger (117) at least one channel (31) for distribution supplied to the heat exchanger fluid coolant and at least one channel (32) for collecting effluent from the heat exchanger fluid heat carrier, which is connected to one side with an internal cavity (121) of the heat exchanger, at least one made them in a hole (31A, 32A), and on the other hand is located on the same short side (117b) heat 117) emerging from the heat exchanger to the outside nozzles (33, 34) for submission to the heat exchanger and the removal from it of a fluid coolant.

7. Installation according to claim 6, characterized in that the channels (31, 32) for distribution supplied to the heat exchanger fluid coolant and collect the effluent from the heat exchanger fluid coolant formed t is obami, located in the inner cavity (121) heat exchanger (117) and fixed at its opposite long sides of (117a).

8. Installation according to claim 7, characterized in that the channels (31, 32) for the distribution and collection of fluid coolant is made in the respective long sides of (117a) of the heat exchanger during its manufacture.

9. Installation according to claim 2, characterized in that the internal cavity (121) of the heat exchanger is divided into a number of chambers (a), not directly communicating with each other, and connected to the channel (31) for distribution supplied to the heat exchanger fluid coolant and the channel (32) for collecting effluent from the heat exchanger fluid coolant through made holes in them (31A, 32A).

10. Installation according to claim 9, characterized in that the camera (a) formed arranged perpendicular to the channels (31, 32) welds (121b), which are welded to each other metal sheets are made of the heat exchanger.

11. Installation according to claim 10, characterized in that each chamber (a) there are many parallel channels (31, 32) partitions (122)forming in the inner cavity of the heat exchanger tortuous path of flow of fluid coolant.

12. Installation according to any one of claims 1 to 11, characterized in that the capacitor has essentially the shape of a cylindrical ring with a Central hole (14) is definitely diameter and consists of a set of heat exchangers (17, 117, 123)arranged radially and distributed into several concentric groups having a common axis.

13. Installation according to claim 2, characterized in that at least one heat exchanger (123) has an internal partition wall (124), which runs from one side (s) to its other, opposite side (123b) and does not reach it at a certain distance, and forms a cavity (125) heat exchanger U-shaped flow of fluid coolant from falling down and rising up areas (125a, 125b), United with the relevant emerging from the heat exchanger to the outside pipe (126, 127).

14. Installation according to item 13, wherein the partition wall (124) is located in the cavity (125) of the heat exchanger at an angle to the side (s) of the heat exchanger and therefore the plots (125a, 125b) U-shaped trajectories have a gradually increasing cross section.

15. Installation according to claim 1, characterized in that the cross-section of the heat exchanger (17, 117, 123) is less than the cross-section of the hatch, which is located on the bottom of the reactor vessel.



 

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12 cl, 9 tbl, 27 dwg

FIELD: industrial organic synthesis and chemical engineering .

SUBSTANCE: invention relates to a process of producing liquid oxygenates, including methanol, C2-C4-alcohols, formaldehyde, lower organic acids, or mixtures thereof, and to installation for implementation the process. Process comprises successively supplying natural gas from complex gas preparation plant to a series of "gas-gas" heat exchangers and into annular space of at least one tubular reaction zone of reactor, wherein natural gas is heated to temperature of the beginning of reaction, whereupon heated gas is passed to the entry of the tubular reaction zone mixer, into which compressed air or oxygen is also injected to provide gas-phase oxidation in reaction zone of reactor. Resulting reaction mixture is discharged from reactor into a series of "gas-liquid" and "gas-gas" heat exchangers, wherein reaction mixture is cooled to ambient temperature and sent to separator, wherefrom liquid phase is passed through lower carboxylic acid recovery vessel to the system of rectification columns to isolate the rest of mixture components, whereas leaving gas is recycled to complex gas preparation plant. More specifically, oxidation is carried out within temperature range 240 to 450°C and pressure from 2 to 10 MPa at residence time of reaction mixture in reactor 2-6 sec and oxidant concentration 2 to 15 wt %. In reactor having mixers hollow and at least one tubular reaction zones, required temperature is maintained constant throughout all length of tubular reaction zone and at entries for compressed air or oxygen in mixers of each of tubular reaction zones and hollow reaction zone. Liquid oxygenate production plant is composed of aforesaid complex gas preparation plant, a series of "gas-gas" heat exchanger to heat natural gas, reactor, a series of "gas-liquid" and "gas-gas" heat exchangers to cool reaction mixture obtained in reactor, gas-liquid separator, lower carboxylic acid recovery vessel, and system of rectification columns to isolate the rest of products.

EFFECT: enabled implementation of the process directly near gas and gas condensate deposits, increased conversion of methane per one passage through reactor, and increased yield of oxygenates due to improved design of plant.

6 cl, 1 dwg, 1 tbl

FIELD: chemical and oil industry.

SUBSTANCE: reactor comprises housing, means for supplying initial components and discharging finished product, unit for heating and cooling made of a number of heat pipes, additional catalyzer applied on the heat pipes and/or housing and made of a coating. The heat pipes are staggered in the space of the housing. The total area of the surface of the heat pipes in the catalytic zone should provide heating and cooling the catalytic zone.

EFFECT: enhanced efficiency.

5 cl, 1 dwg

FIELD: chemical engineering.

SUBSTANCE: reactor comprises first heated section that has the first flowing passage and causes the first reaction in the first flowing passage, heating section that heats the first heated section, and the second heated section that has the second flowing passage and causes the second reaction or evaporation in the second flowing section by the heat from the heating section transported through the first heated section. The first and second heated sections are defined on the substrate. The reactor may be provided with the third heated section that has third flowing passage and causes evaporation in the third flowing passage by the heat from the heating section transported through the second heated section. The evaporated fuel is transformed for generation in the first heated section, and in the second section the carbon oxide is removed. The second reaction or evaporation are caused at a temperature that is lower than that of the first reaction. The chemical reactor has a number of substrates mounted in layers one above the other and is used as a member of the fuel cell.

EFFECT: simplified structure and reduced sizes.

27 cl, 12 dwg

FIELD: chemical industry; heat engineering; apparatuses for realization of the gas liquid chemical processes and heat-exchange and mass-exchange processes.

SUBSTANCE: the invention is pertaining to the apparatuses for realization of the gas liquid chemical processes and heat-exchange and mass-exchange processes with a great release or absorption of heat, in particular, the processes of liquid-phase oxidation of alkyl aromatic monocarboxylic and polycarboxylic acids. The invention presents the reactor consisting of the vertical cylindrical body partitioned in height by horizontal planar septums with holes into sections containing the bundles of the barbotage and circulation pipes fixed on the pipe plates, the fitting pipes for the reactants and heat-carrying agent feeding in and withdrawal. Between the sections there are the separating devices made in the form of the reflective funnels with holes in the center, in internal cavities of which there are the dipped barbotage cylinders and the circulation fitting pipes fixed on the horizontal septums in such a manner that the barbotage cylinders are mounted in the center are established, and the circulation fitting pipes are placed in symmetry outside the barbotage cylinders. At that the bottom parts of the barbotage cylinders located under the horizontal septums have a perforation in the form of slits or holes, and upper parts of the barbotage cylinders located above the horizontal septums are supplied with the heads made in the form of bundles of upright tubes, pellets or perforated plates creating in them resistance to the up-going gaseous current. The invention allows to increase productivity of the reactor by decreasing dispersion of duration of liquid reactants presence in the segmented reaction zone, as well as to raise the hydrodynamic efficiency and stability of the reactor operation due to organization of the discrete gas separation from the gas-saturated liquid in conditions of the countercurrent motion of the gas and the liquid in height of the reactionary volume.

EFFECT: the invention ensures an increase of productivity of the reactor, its hydrodynamic efficiency and stability of operation.

3 cl, 6 dwg, 1 tbl

FIELD: chemical or physical processes.

SUBSTANCE: reactor comprises housing with bubbler mounted in the bottom section of the housing and provided with submersible pipe and by-bass connecting pipe for discharging the reaction fluid that is arranged in the top section of the housing and is connected with the pipe-cross-piece upstream of the inlet connecting pipe of the housing of the next reactor. The space near the connecting pipe for discharging the reaction fluid is bounded from above by the near bottom space with bottom and vertical edges arranged at the level of the reaction fluid in the reactor. The top section of the submersible pipe is connected with the bottom of the near-wall space, and bottom part of the submersible pipe is set at the site of intersection of the vertical axis of the reactor housing and horizontal axes of the bubbler. The near-wall space can be made of a tank with the bottom mounted separately and connected with the top section of the submersible pipe and tank wall connected with the connecting pipe for discharging the reaction fluid.

EFFECT: enhanced efficiency.

2 cl, 3 dwg

FIELD: chemical and oil refining industries; gas-and-liquid reactors for hydrocarbon material oxidation process by atmospheric oxygen.

SUBSTANCE: proposed gas-and-liquid reactor has vertical cylindrical housing with partition inside it and device secured on this partition for condensation of heavy hydrocarbons from waste oxidation gases, cavitation vortex apparatus made in form of mixing and foam chambers interconnected by means of convergent nozzle and the following technological branch pipes: branch pipe for introduction of raw material into cavitation vertex apparatus in form of nozzle with cavitation ring located along axis of mixing chamber, air supply branch pipe mounted tangentially, branch pipe for discharge of reaction products and branch pipe for discharge of finished oxidized product which is mounted on side of reactor. Reactor is additionally provided with branch pipe for delivery of 5-10% starting raw material to zone above partition on which blind plate for condensation of heavy hydrocarbons from waste oxidation gases is secured and branch pipe for delivery of heavy hydrocarbons in mixture with 90-95% of starting raw material to cavitation vertex apparatus.

EFFECT: enhanced efficiency of reactor due to effective mass exchange at full use of atmospheric oxygen; improved quality of bitumen.

3 cl, 1 dwg

FIELD: chemical industry; devices and methods of production of carbamate.

SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to carbamatecondenserof the sinking type used in the installation for production of the synthesized carbamide from the gaseous carbon dioxide and the liquid ammonia. The condenser (1) of the sinking type contains the bundle (5) of pipes, in which the condensation of the gaseous compounds is exercised and as a result of the interaction of ammonia with carbon dioxide the carbamate is formed. The condenser differs from others by availability the condensate circulating pipe (19, 23) structurally not connected with the bundle (5) of pipes and designed for circulation of the components in the closed contour of the condenser (1)of the part of the condensed inside it gaseous compounds. The availability of the separate circulating pipe structurally not connected with the bundle of the condensation pipes and communicating with the upper and the lower parts of the condenser ensures the possibility of circulation of the carbamate passing over of the bundle of the condensation pipes, what allows to increase essentially the output of carbamate gained as a result of condensation.

EFFECT: the invention allows to raise essentially the output of carbamate gained as a result of condensation.

6 cl, 3 dwg

FIELD: gas-processing industry; petroleum industry; other industries; gas-cleaning equipment.

SUBSTANCE: the invention is pertaining to the designs of the gas-cleaning equipment of industrial and domestic designation and may be used in various branches of industry. The installation contains: the body forming a reaction zone; the conical unit forming a zone of dispersion; the located inside the body shaft with a drive unit and a feeding screw supplied with solid plates, the dispersion grates and calibrating grates; the branch-pipe for feeding the gas for cleaning; the absorber feeding union; the drips separator and the slime separator. The installation is supplied with the cylinder forming the absorption area, integrated with the tank-collector supplied with the distributing grate for sprinkling by the absorber of the gas subjected to cleaning. The tank-collector is supplied with the chutes for feeding the absorber in the channels of the feeding screw. The installation ensures a high level of cleaning of the gases from toxic impurity, from dust and mists, a high degree of trapping of the raw and the finished products.

EFFECT: the invention ensures a high level of cleaning of the gases from toxic impurity, a dust and mists, the high degree of trapping of the raw and the finished products.

3 dwg

FIELD: chemical industry; reactors to run reactions of oxidation.

SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to reactors to run reactions of oxidation of a liquid by a gas. The reactor may be used for oxidation of a hydrocarbon, for example, cyclohexane with formation of cyclohexyl hydroperoxide, cyclohexanol, cyclohexanone and-or adipinic acid. The reactor is divided into stages by the separating plates supplied with the through holes. The holes are uniformly distributed along the surface of the separating plates, coincide with the unidirectional flow of the reaction mixture and prevent accumulation of a gas under each plate. The plates have a coefficient of rectification in the interval from 10 up to 50 %. An oxidable compound and an oxidizing gas containing oxygen are fed only into the bottom part of the reactor. The offered invention is simple in operation, allows to increase output of the final product and to avoid the risk of a self-inflammation of the gas mixture.

EFFECT: the invention is simple in operation, ensures increased output of the final product and lets to avoid the risk of a self-inflammation of the gas mixture.

8 cl, 7 dwg

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