A steam recovery system based on absorption technology

Abstract

The present invention discloses a steam recovery system based on absorption technology, which relates to the technical field of synthetic rubber production. The main structure includes an oil-water separation tank, a flash tank, a coagulation kettle, a hot water tank, a first absorption heat pump and a second absorption heat pump. The oil-water separation tank is used for separating oil and water to recover solvent oil. The flash tank is used for flashing hot water to form steam. The coagulation kettle is used for steam stripping the mixed rubber solution. The hot water tank is used to provide hot water. The first absorption heat pump uses the heat of the oil-water mixed gas lifted by the evaporator and the generator to heat the hot water. The second absorption heat pump uses the waste heat of the oil-water mixture and the circulating cooling water absorbed by the evaporator to heat the circulating medium-temperature water. Through the combined application of the first absorption heat pump and the second absorption heat pump, not only can steam for rubber process be produced, but also low-grade waste heat can be fully utilized, significantly reducing the steam consumption in the rubber production process and lowering the production cost of synthetic rubber.

Description

Technical Field

[0001] The present invention relates to the technical field of synthetic rubber production, and particularly to a steam recovery system based on absorption technology. Background Art

[0002] China is a large rubber-consuming country, consuming about 38% of the world's total rubber consumption every year. Rubber production belongs to the chemical industry, and a large amount of fossil energy is consumed during the synthesis process, resulting in a large energy consumption in the whole industry. The production process of synthetic rubber usually adopts the wet coagulation and devolatilization method, which requires a large amount of steam to remove solvents. About 2 / 3 of the steam will be directly discharged with the mixed gas stripping gas, causing a large waste of steam. Therefore, directly or indirectly improving the steam utilization rate can improve the production efficiency of synthetic rubber and save production costs. Summary of the Invention

[0003] To solve the above technical problems, the present invention provides a steam recovery system based on absorption technology. Through this system, not only can the heat energy of unused steam and the waste heat of circulating cooling water be recovered in large quantities, but also the recovered heat energy can be converted into steam for reuse, significantly improving the steam utilization rate and reducing the production cost in the synthetic rubber process.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a steam recovery system based on absorption technology, including a coagulation kettle, a first absorption heat pump, a second absorption heat pump, a hot water tank, a flash tank, and an oil-water separation tank; steam sequentially passes through the coagulation kettle, the first absorption heat pump, and the second absorption heat pump and enters the oil-water separation tank; a circulating cooling medium circulates between the first absorption heat pump and the second absorption heat pump; a circulating heat medium flows through the second absorption heat pump and enters the hot water tank; the water in the hot water tank absorbs the heat in the first absorption heat pump and the second absorption heat pump to supplement steam to the coagulation kettle, or the water in the hot water tank absorbs the heat in the first absorption heat pump and the second absorption heat pump and supplements steam through the flash tank.

[0006] Optionally, the first absorption heat pump includes a first evaporator, a first absorber, a first generator, and a first condenser; the inlet of the first evaporator is connected to the coagulation kettle, and the outlet of the first evaporator is connected to the inlet of the first generator; the first condenser is connected to the second absorption heat pump, and a circulating cooling medium passes through the first condenser; the inlet of the first absorber is connected to the hot water tank, and the outlet of the first absorber is connected to the coagulation kettle and the flash tank.

[0007] Optionally, a first regulating valve is provided between the outlet of the first absorber and the coagulation kettle; a second regulating valve is provided between the outlet of the first absorber and the flash tank.

[0008] Optionally, a third regulating valve is provided between the flash tank and the main steam pipeline.

[0009] Optionally, the second absorption heat pump includes a second evaporator, a second absorber, a second generator and a second condenser; the inlet of the second generator is connected to the lower part of the hot water tank; the outlet of the second generator is connected to the upper part of the hot water tank; the inlet of the second absorber is connected to the main pipeline of the circulating heat medium, the outlet of the second absorber is connected to the inlet of the second condenser, and the outlet of the second condenser is connected to the hot water tank; the second evaporator is connected to the first absorption heat pump, and a circulating cooling medium is passed through the second evaporator. The inlet of the second evaporator is connected to the first absorption heat pump, and the outlet of the second evaporator is connected to the oil-water separation tank.

[0010] Optionally, a plurality of nozzles are provided inside both the coagulation kettle and the flash tank, and the plurality of nozzles are used for atomizing hot water.

[0011] Optionally, the circulating cold medium is circulating cooling water.

[0012] Optionally, the circulating heat medium is circulating medium-temperature water.

[0013] The present invention has achieved the following technical effects compared with the prior art:

[0014] In the steam recovery system based on absorption technology in the present invention, the mixed gas stripping gas discharged from the coagulation kettle is successively absorbed by the first evaporator, the first generator and the second evaporator, and the temperature is reduced to a set value and then flows into the oil-water separation tank. The hot water absorbs heat in the first absorber and the temperature rises, and then flows into the coagulation kettle and the flash tank respectively to generate steam, which is used as the supplementary steam of the main steam. At the same time, the hot water releases heat in the second generator and the temperature drops, and then flows back to the hot water tank as the supplementary medium-temperature water of the hot water tank. The circulating medium-temperature water absorbs heat in the second absorber and the second condenser in turn, and the temperature rises and is also used as the supplementary water of the hot water tank. The circulating cooling water absorbs heat in the first condenser and the temperature rises, and then flows into the second evaporator to release heat and the temperature drops. This system absorbs the heat of the mixed gas stripping gas through the second absorption heat pump and uses hot water to produce steam. At the same time, it combines with the first absorption heat pump to absorb the heat of the circulating cooling medium and heat the circulating heating medium. At the same time, it recovers the heat of the mixed gas stripping gas and the circulating cooling water, improves the energy utilization rate, reduces the consumption of the main steam, and has obvious energy-saving benefits. It can not only produce steam for rubber technology, but also make full use of low-grade waste heat, greatly reduce the steam consumption in the rubber production process, and reduce the production cost of synthetic rubber. Brief Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings required for use in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0016] Figure 1 It is a schematic structural diagram of the steam recovery system based on absorption technology of the present invention.

[0017] Description of the reference numerals: 1 - Oil - water separation tank, 2 - Flash tank, 3 - Coagulation kettle, 4 - Hot water tank, 5 - First regulating valve, 6 - Second regulating valve, 7 - Third regulating valve, 10 - First absorption heat pump, 11 - First evaporator, 12 - First absorber, 13 - First generator, 14 - First condenser, 20 - Second absorption heat pump, 21 - Second generator, 22 - Second condenser, 23 - Second absorber, 24 - Second evaporator. Detailed Embodiments

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0019] As Figure 1 shown, this embodiment provides a steam recovery system based on absorption technology, including a coagulation kettle 3, a first absorption heat pump 10, a second absorption heat pump 20, a hot water tank 4, a flash tank 2, and an oil - water separation tank 1; steam sequentially passes through the coagulation kettle 3, the first absorption heat pump 10, the second absorption heat pump 20 and enters the oil - water separation tank 1; circulating cooling water circulates between the first absorption heat pump 10 and the second absorption heat pump 20; circulating medium - temperature water flows through the second absorption heat pump 20 and enters the hot water tank 4; the water in the hot water tank 4 absorbs the heat in the first absorption heat pump 10 and the second absorption heat pump 20 to supplement steam to the coagulation kettle 3, or the water in the hot water tank 4 absorbs the heat in the first absorption heat pump 10 and the second absorption heat pump 20 and supplements steam through the flash tank 2.

[0020] In this specific embodiment, the first absorption heat pump 10 includes a first evaporator 11, a first absorber 12, a first generator 13, and a first condenser 14; the inlet of the first evaporator 11 is communicated with the agglomeration kettle 3, and the outlet of the first evaporator 11 is communicated with the inlet of the first generator 13; the first condenser 14 is communicated with the second evaporator 24 in the second absorption heat pump 20, and circulating cooling water is passed through the first condenser 14; the inlet of the first absorber 12 is communicated with the hot water tank 4, and the outlet of the first absorber 12 is communicated with the agglomeration kettle 3 and the flash tank 2.

[0021] The second absorption heat pump 20 includes a second evaporator 24, a second absorber 23, a second generator 21, and a second condenser 22; the inlet of the second generator 21 is communicated with the lower part of the hot water tank 4; the outlet of the second generator 21 is communicated with the upper part of the hot water tank 4; the inlet of the second absorber 23 is communicated with the main circulating warm water pipeline, the outlet of the second absorber 23 is communicated with the inlet of the second condenser 22, and the outlet of the second condenser 22 is communicated with the hot water tank 4; the second evaporator 24 is communicated with the first condenser 14 in the first absorption heat pump 10, and circulating cooling water is passed through the second evaporator 24. The inlet of the second evaporator 24 is communicated with the first absorption heat pump 10, and the outlet of the second evaporator 24 is communicated with the oil-water separation tank 1.

[0022] The hot water in the hot water tank 4 serves as the driving heat source for the second absorption heat pump 20, and the hot water flows back to the hot water tank 4 after flowing through the second generator 21.

[0023] A first regulating valve 5 is arranged between the outlet of the first absorber 12 and the agglomeration kettle 3; a second regulating valve 6 is arranged between the outlet of the first absorber 12 and the flash tank 2; a third regulating valve 7 is arranged between the flash tank 2 and the steam main pipeline.

[0024] A plurality of nozzles are arranged inside both the agglomeration kettle 3 and the flash tank 2, and the plurality of nozzles are used for atomizing hot water. The water in the hot water tank 4 flows through the first absorber 12 to absorb heat, then flows into the agglomeration kettle 3 and the flash tank 2 and is sprayed out through the plurality of nozzles, forming steam inside the agglomeration kettle 3 and the flash tank 2, supplementing the steam, and reducing the steam consumption.

[0025] The steam is discharged from the condensation kettle 3 to form an oil-water mixed gas stripping gas. The oil-water mixed gas stripping gas sequentially passes through the first evaporator 11, the first generator 13 and the second evaporator 24 to release heat and the temperature decreases, and then enters the oil-water separation tank 1. Circulating cooling water is passed through the first condenser 14. The outlet of the circulating cooling water in the first condenser 14 is communicated with the inlet of the circulating cooling water in the second evaporator 24. The circulating cooling water absorbs heat and the temperature increases in the first condenser 14, and then releases heat and the temperature decreases in the second evaporator 24, completing the energy cycle of the circulating cooling water. The hot water in the hot water tank 4 is passed into the first absorber 12 to absorb heat and the temperature increases. The hot water inlet in the condensation kettle 3 and the hot water inlet in the flash tank 2 are connected in parallel and communicated with the outlet of the hot water in the first absorber 12. The first regulating valve 5 is located on the hot water branch of the condensation kettle 3 to adjust its opening degree. The second regulating valve 6 is located on the hot water branch of the flash tank 2 to adjust its opening degree. The hot water flows into the condensation kettle 3 and is atomized when sprayed from the nozzle. At the same time, the hot water flowing into the flash tank 2 generates steam through the nozzle. The steam outlet in the flash tank 2 is communicated with the steam main pipeline through the third regulating valve 7 as supplementary steam. The hot water outlet in the hot water tank 4 is communicated with the hot water inlet in the second generator 21. The hot water is used as the driving heat source of the second absorption heat pump 20. The hot water outlet in the second generator 21 is communicated with the hot water inlet in the hot water tank 4. The hot water with reduced temperature after doing work flows back to the hot water tank 4 as supplementary feed water. Circulating medium-temperature water is passed through the second absorber 23. The outlet of the circulating medium-temperature water in the second absorber 23 is communicated with the inlet of the circulating medium-temperature water in the second condenser 22. The outlet of the circulating medium-temperature water in the second condenser 22 is communicated with the inlet of the circulating medium-temperature water in the hot water tank 4. The circulating medium-temperature water absorbs the heat of the second evaporator 24 and the temperature increases, and then is passed into the hot water tank 4 as its supplementary feed water. That is, the hot water brings the heat of the mixed gas stripping gas absorbed by the first absorption heat pump 10 into the condensation kettle 3, thus reducing the steam consumption. At the same time, the flash steam generated by the flash tank 2 as supplementary steam also reduces the steam consumption, and the waste heat of the circulating cooling medium is fully utilized, achieving the effect of energy conservation and consumption reduction.

[0026] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0027] In this specification, specific examples are used to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation on the present invention.

Claims

1. A steam recovery system based on absorption technology, characterized in that It includes a coagulation kettle, a first absorption heat pump, a second absorption heat pump, a hot water tank, a flash tank and an oil-water separation tank; steam sequentially passes through the coagulation kettle, the first absorption heat pump, the second absorption heat pump and enters the oil-water separation tank; the circulating cooling medium circulates between the first absorption heat pump and the second absorption heat pump; the circulating heat medium flows through the second absorption heat pump and enters the hot water tank; the water in the hot water tank absorbs the heat in the first absorption heat pump and the second absorption heat pump to supplement steam to the coagulation kettle, or the water in the hot water tank absorbs the heat in the first absorption heat pump and the second absorption heat pump and supplements steam through the flash tank; The first absorption heat pump includes a first evaporator, a first absorber, a first generator and a first condenser; the inlet of the first evaporator is communicated with the coagulation kettle, and the outlet of the first evaporator is communicated with the inlet of the first generator; the first condenser is communicated with the second absorption heat pump, and the circulating cooling medium passes through the first condenser; the inlet of the first absorber is communicated with the hot water tank, and the outlet of the first absorber is communicated with the coagulation kettle and the flash tank; A first regulating valve is arranged between the outlet of the first absorber and the coagulation kettle; a second regulating valve is arranged between the outlet of the first absorber and the flash tank; A third regulating valve is arranged between the flash tank and the steam main pipeline; The second absorption heat pump includes a second evaporator, a second absorber, a second generator and a second condenser; the inlet of the second generator is communicated with the lower part of the hot water tank; the outlet of the second generator is communicated with the upper part of the hot water tank; the inlet of the second absorber is communicated with the main pipeline of the circulating heat medium, the outlet of the second absorber is communicated with the inlet of the second condenser, and the outlet of the second condenser is communicated with the hot water tank; the second evaporator is communicated with the first absorption heat pump, and the circulating cooling medium passes through the second evaporator, the inlet of the second evaporator is communicated with the first absorption heat pump, and the outlet of the second evaporator is communicated with the oil-water separation tank; A plurality of nozzles are arranged inside the coagulation kettle and the flash tank, and the plurality of nozzles are used for atomizing hot water.

2. The steam recovery system based on absorption technology according to claim 1, characterized in that The circulating cooling medium is circulating cooling water.

3. The steam recovery system based on absorption technology according to claim 1, wherein The circulating heat medium is circulating medium-temperature water.

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