Energy-saving system and method in ABS production system

Abstract

The present invention discloses an energy-saving system and method in an ABS production system, which solves the technical problem of high energy consumption in the prior art emulsion grafting-bulk SAN blending method and continuous bulk method ABS production system. The energy-saving system includes a thermal oil furnace, a hot water tank, a condenser, a chilled water tank, an ammonia absorption refrigeration device and a heat exchange mechanism. The energy-saving method is to replace the heat of high-temperature flue gas with a heat exchange mechanism to become a heat source for the operation of the refrigerant medium in the generator of the ammonia absorption refrigeration device, and the ammonia absorption refrigeration device reduces the temperature of 0°C chilled water to -5°C for users. The present invention uses hot water as a carrier, and utilizes the waste heat of the flue gas of the thermal oil furnace to heat 95°C hot water to 115°C and send it to the ammonia absorption refrigeration device, which is used as a heat source to drive the refrigerant medium in the ammonia absorption refrigeration device to work, and reduces the temperature of the chilled return water from 0°C to -5°C for users. It does not need to use an electrically driven compression refrigeration unit to reduce the 0°C chilled water to -5°C chilled water for users, which reduces power consumption and can achieve cost reduction and efficiency improvement in ABS production.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical industry, and in particular relates to an energy-saving system and method in an ABS production system. Background Art

[0002] The devolatilization process of the emulsion grafting-bulk SAN blending method SAN device and the continuous bulk method ABS requires heat transfer oil at ~280°C, and is usually equipped with a heat transfer oil furnace. The flue gas temperature in the heat transfer oil furnace can reach 280°C; the condenser in the devolatilization process requires chilled water, usually -5°C.

[0003] At present, there is unreasonable energy utilization in the ABS production process. On the one hand, the flue gas with a temperature of up to 280°C in the heat transfer oil furnace that supplies heat transfer oil to the SAN device of the emulsion grafting-bulk SAN blending method and the continuous bulk ABS devolatilization process is discharged into the air without being fully utilized, resulting in energy loss. On the other hand, the -5°C chilled water (ethylene glycol aqueous solution) used in the continuous bulk ABS devolatilization process is produced by an electric-driven compression refrigeration unit, which has high power consumption.

[0004] Therefore, designing an energy-saving system and method in an ABS production system to make energy utilization in the ABS production process more scientific and energy-saving has become a technical problem that needs to be urgently solved by technicians in the relevant technical field. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an energy-saving system and method in an ABS production system to at least solve some of the above technical problems.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] An energy-saving system in an ABS production system comprises a heat transfer oil furnace for providing heat transfer oil for the ABS production system, a condenser in a devolatilization process of the ABS production system, a chilled water tank for providing chilled water for the condenser, an ammonia absorption refrigeration device connected between the chilled water tank and the condenser for cooling the chilled water, and a heat exchange mechanism respectively connected to the heat transfer oil furnace and the ammonia absorption refrigeration device for exchanging the heat of flue gas in the heat transfer oil furnace into refrigeration power for the ammonia absorption refrigeration device.

[0008] Furthermore, the ammonia absorption refrigeration device includes a generator connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator connected between the chilled water tank and the condenser, an absorber connected from the evaporator and connected to the generator and storing an ammonia-lean liquid absorbent, and a gas ammonia condenser connected from the generator and connected to the evaporator.

[0009] Furthermore, the gas ammonia condenser and the evaporator are connected by a pipeline, and a first throttle valve is provided on the pipeline.

[0010] Furthermore, the absorber and the generator are connected by a pipeline and a booster pump is provided on the pipeline.

[0011] Furthermore, an ammonia-lean liquid absorbent reflux pipe is connected between the generator and the absorber, and a second throttle valve is provided on the ammonia-lean liquid absorbent reflux pipe.

[0012] Furthermore, the evaporator is a shell and tube evaporator, the shell side of the evaporator is respectively connected to the gas ammonia condenser and the absorber, a chilled water delivery pipe is connected between the chilled water tank and the condenser, and the tube side of the evaporator is connected to the chilled water delivery pipe.

[0013] Furthermore, a chilled water circulation pump is provided on the chilled water delivery pipe.

[0014] Furthermore, a chilled water return pipe is connected between the chilled water tank and the condenser.

[0015] Furthermore, the heat exchange mechanism includes a first heat exchange tube arranged in the flue gas channel in the thermal oil furnace, a second heat exchange tube connected from the first heat exchange tube and arranged in the generator, and a hot water tank connected from the second heat exchange tube and connected to the first heat exchange tube; the hot water tank and the first heat exchange tube are connected by a pipeline and a hot water circulation pump is provided on the pipeline.

[0016] A method for energy-saving system in ABS production system, wherein the heat of high-temperature flue gas in a heat-conducting oil furnace is replaced by a heat exchange mechanism to a generator in an ammonia absorption refrigeration device for use as a heat source, a high-pressure ammonia-rich liquid absorbent in the generator absorbs heat and vaporizes into high-temperature and high-pressure gas ammonia, the high-temperature and high-pressure gas ammonia is condensed into high-pressure liquid ammonia and enters an evaporator after throttling to evaporate into low-pressure gas ammonia and is recovered into the generator, and a pipeline for supplying chilled water to a condenser cools the chilled water therein from 0°C to -5°C after passing through the evaporator, so as to realize the use of 0°C chilled water to provide -5°C chilled water for the condenser.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The invention has a simple structure, a scientific and reasonable design, and is easy to use. It uses hot water as a carrier and utilizes the waste heat of the flue gas of the thermal oil furnace to heat 95°C hot water to 115°C and sends it to the ammonia absorption refrigeration device, and uses it as a heat source to drive the refrigeration medium in the ammonia absorption refrigeration device to work, and reduces the chilled return water temperature from 0°C to -5°C for users to use. It does not need to use an electrically driven compression refrigeration unit to reduce 0°C chilled water to -5°C chilled water for users to use, thereby reducing power consumption and achieving cost reduction and efficiency improvement in ABS production.

[0019] For a 200,000 ton / year emulsion grafting-bulk SAN blending ABS plant, the SAN device uses an electric drive compression type refrigeration unit with a capacity of 1000kW, and its power consumption is ~360kW. The power consumption of the pump of the present invention is ~60kW, and the annual electricity saving is ~2,400,000kWh. The industrial electricity price is 0.6 yuan / kWh, and the annual electricity cost saving is 1.44 million yuan. Therefore, the present invention has a high promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the energy-saving system in the ABS production system of the present invention.

[0021] The names corresponding to the reference numerals are:

[0022] 1-thermal oil furnace; 2-hot water circulation pump; 3-hot water tank; 4-absorber; 5-boosting pump; 6-generator; 7-gas ammonia condenser; 8-evaporator; 9-chilled water circulation pump; 10-chilled water tank; 11-condenser; 12-first throttle valve; 13-ammonia-lean liquid absorbent return pipe; 14-second throttle valve; 15-chilled water delivery pipe; 16-chilled water return pipe; 17-first heat exchange pipe; 18-second heat exchange pipe; 19-ammonia absorption refrigeration device; 20-thermal oil furnace system; 21-thermal oil supply pipe; 22-thermal oil return pipe. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] Embodiment 1, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device 19 connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device.

[0025] The invention has a simple structure, a scientific and reasonable design, and is easy to use. It uses hot water as a carrier and utilizes the waste heat of the flue gas of the thermal oil furnace to heat 95°C hot water to 115°C and sends it to the ammonia absorption refrigeration device, and uses it as a heat source to drive the refrigeration medium in the ammonia absorption refrigeration device to work, and reduces the chilled return water temperature from 0°C to -5°C for users to use. It does not need to use an electrically driven compression refrigeration unit to reduce 0°C chilled water to -5°C chilled water for users to use, thereby reducing power consumption and achieving cost reduction and efficiency improvement in ABS production.

[0026] Embodiment 2, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8.

[0027] Based on Example 1, this Example 2 provides a more preferred structure of the ammonia absorption refrigeration device, specifically: the ammonia absorption refrigeration device includes a generator 6 connected to a heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between a chilled water tank 10 and a condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing an ammonia-lean liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. Through the above structure, the high-pressure ammonia-rich liquid absorbent evaporates high-temperature and high-pressure gas ammonia through the heat source provided by the heat exchange mechanism. The high-temperature and high-pressure gas ammonia is condensed into high-pressure liquid ammonia through the gas ammonia condenser 7. The high-pressure liquid ammonia is throttled into low-temperature and low-pressure liquid ammonia and then enters the evaporator 8 to absorb heat and evaporate into low-pressure gas ammonia. The low-pressure gas ammonia enters the absorber 4 and is absorbed by the ammonia-poor liquid absorbent. The ammonia-poor liquid absorbent absorbs the low-pressure gas ammonia to become ammonia-rich liquid absorbent and is then transported to the generator 6 to form a cycle. When the low-temperature and low-pressure liquid ammonia absorbs heat and evaporates into low-pressure gas ammonia in the evaporator 8, the chilled water provided to the condenser 11 can be reduced from 0°C to -5°C. This can effectively reduce power consumption and achieve cost reduction and efficiency improvement in ABS production.

[0028] Embodiment 3, as Figure 1As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. The gas ammonia condenser 7 and the evaporator 8 are connected by a pipeline, and a first throttle valve 12 is provided on the pipeline.

[0029] Based on Example 2, this Example 3 provides a more preferred connection structure between the gas ammonia condenser 7 and the evaporator 8, specifically: the gas ammonia condenser 7 and the evaporator 8 are connected by a pipeline and the pipeline is provided with a first throttle valve 12. Through the above structure, the high-pressure liquid ammonia from the gas ammonia condenser 7 is throttled into low-temperature and low-pressure liquid ammonia at the first throttle valve 12, which can effectively improve the heat absorption and evaporation efficiency of the evaporator 8.

[0030] Embodiment 4, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power of the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. The absorber 4 is connected to the generator 6 by a pipeline, and a booster pump 5 is provided on the pipeline.

[0031] Based on Example 2, this Example 4 provides a more preferred connection structure between the absorber 4 and the generator 6, specifically: the absorber 4 and the generator 6 are connected by a pipeline and a booster pump 5 is provided on the pipeline. Through the above structure, the liquid absorbent that absorbs enough gaseous ammonia is converted into a high-pressure ammonia-rich liquid absorbent under the action of the booster pump 5 and is pumped into the generator 6. This can effectively ensure the stable and continuous operation of the system.

[0032] Embodiment 5, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. An ammonia-lean liquid absorbent reflux pipe 13 is connected between the generator 6 and the absorber 4 , and a second throttle valve 14 is provided on the ammonia-lean liquid absorbent reflux pipe 13 .

[0033] Based on Example 2, this Example 5 provides a more preferred connection structure between the absorber 4 and the generator 6, specifically: an ammonia-poor liquid absorbent reflux pipe 13 is connected between the generator 6 and the absorber 4, and a second throttle valve 14 is provided on the ammonia-poor liquid absorbent reflux pipe 13. Through the above structure, the high-pressure ammonia-rich liquid absorbent in the generator 6 evaporates high-temperature and high-pressure gas ammonia after the heat exchange mechanism provides a heat source, and enters the gas ammonia condenser 7 through the pipeline, and the high-pressure ammonia-poor liquid absorbent retained in the generator 6 circulates through the ammonia-poor liquid absorbent reflux pipe 13 and flows into the absorber 4 to form a cycle. The second throttle valve 14 can effectively throttle the high-pressure ammonia-poor liquid absorbent into a low-pressure ammonia-poor liquid absorbent, which is beneficial for the absorber 4 to absorb the low-pressure gas ammonia from the evaporator 8.

[0034] Embodiment 6, as Figure 1As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. The evaporator 8 is a shell and tube evaporator. The shell side of the evaporator 8 is respectively connected to the gas ammonia condenser 7 and the absorber 4. A chilled water delivery pipe 15 is connected between the chilled water tank 10 and the condenser 11. The tube side of the evaporator 8 is connected to the chilled water delivery pipe 15.

[0035] Based on Example 2, this Example 6 provides a more preferred connection structure between the evaporator 8, the gas ammonia condenser 7, the absorber 4, the chilled water tank 10 and the condenser 11, specifically: the evaporator 8 is a shell and tube evaporator, the shell side of the evaporator 8 is respectively connected to the gas ammonia condenser 7 and the absorber 4, a chilled water delivery pipe 15 is connected between the chilled water tank 10 and the condenser 11, and the tube side of the evaporator 8 is connected to the chilled water delivery pipe 15. With such a design, the high-temperature and high-pressure gas ammonia is cooled by the gas ammonia condenser 7 and becomes high-pressure liquid ammonia, and the high-pressure liquid ammonia is converted into low-pressure liquid ammonia under the action of the throttle valve and enters the shell side of the evaporator 8. The low-pressure liquid ammonia in the shell side of the evaporator 8 evaporates into low-pressure gas ammonia. This process is endothermic conversion. The low-pressure gas ammonia enters the absorber 4 through the pipeline in the shell side of the evaporator 8 and is absorbed by the ammonia-poor liquid absorbent in the absorber 4. The 0°C chilled water in the chilled water tank 10 is transported to the condenser 11 in the devolatilization process of the ABS production system or other users who need chilled water through the chilled water delivery pipe 15. The chilled water delivery pipe 15 is connected in series with the tube side of the evaporator 8. During the process, heat is provided for the low-pressure liquid ammonia to evaporate into low-pressure gaseous ammonia, so that the 0°C chilled water in the tube side of the evaporator 8 is converted into -5°C chilled water, thereby achieving the purpose of using the 0°C chilled water in the chilled water tank 10 to provide -5°C chilled water for the condenser 11 in the devolatilization process of the ABS production system or other users who need -5°C chilled water.

[0036] The present invention uses hot water as a carrier and utilizes the waste heat of the flue gas of the thermal oil furnace to heat 95°C hot water to 115°C and sends it to the ammonia absorption refrigeration device, which serves as a heat source to drive the refrigerant medium in the ammonia absorption refrigeration device to work, and reduces the chilled return water temperature from 0°C to -5°C for users to use. It does not need to use an electrically driven compression refrigeration unit to reduce 0°C chilled water to -5°C chilled water for users to use, thereby reducing power consumption and achieving cost reduction and efficiency improvement in ABS production.

[0037] Embodiment 7, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat-conducting oil furnace 1 into refrigeration power for the ammonia absorption refrigeration device. The ammonia absorption refrigeration device includes a generator 6 connected to the heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator 8 connected between the chilled water tank 10 and the condenser 11, an absorber 4 connected from the evaporator 8 and connected to the generator 6 and storing a poor ammonia liquid absorbent, and a gas ammonia condenser 7 connected from the generator 6 and connected to the evaporator 8. The evaporator 8 is a shell and tube evaporator, the shell side of the evaporator 8 is respectively connected to the gas ammonia condenser 7 and the absorber 4, a chilled water delivery pipe 15 is connected between the chilled water tank 10 and the condenser 11, and the tube side of the evaporator 8 is connected to the chilled water delivery pipe 15. The chilled water delivery pipe 15 is provided with a chilled water circulation pump 9.

[0038] Based on the embodiment 6, the embodiment 7 provides a more preferred structure of the chilled water delivery pipe 15, specifically: a chilled water circulation pump 9 is provided on the chilled water delivery pipe 15. Such a design can effectively ensure that the chilled water tank 10 delivers chilled water to the condenser 11.

[0039] Embodiment 8, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of the flue gas in the heat-conducting oil furnace 1 into the refrigeration power of the ammonia absorption refrigeration device. A chilled water return pipe 16 is connected between the chilled water tank 10 and the condenser 11.

[0040] Based on Example 1, this Example 8 provides a more preferred connection structure between the chilled water tank 10 and the condenser 11, specifically: a chilled water return pipe 16 is connected between the chilled water tank 10 and the condenser 11. With such a design, after the condenser 11 is used and the -5°C chilled water is converted into 0°C chilled water, it can flow back to the chilled water tank 10 through the chilled water return pipe 16, thus forming a cycle, which can effectively save water.

[0041] Embodiment 9, as Figure 1 As shown, the present invention provides an energy-saving system in an ABS production system, including a heat-conducting oil furnace 1 for providing heat-conducting oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser 11 in the devolatilization process of the ABS production system, a chilled water tank 10 for providing chilled water to the condenser 11, an ammonia absorption refrigeration device connected between the chilled water tank 10 and the condenser 11 for cooling the chilled water, and a heat exchange mechanism connected to the heat-conducting oil furnace 1 and the ammonia absorption refrigeration device respectively for exchanging the heat of the flue gas in the heat-conducting oil furnace 1 into the refrigeration power of the ammonia absorption refrigeration device. The heat exchange mechanism includes a first heat exchange tube 17 arranged in the flue gas channel in the heat-conducting oil furnace 1, a second heat exchange tube 18 connected from the first heat exchange tube 17 and arranged in the generator 6, and a hot water tank 3 connected from the second heat exchange tube 18 and connected to the first heat exchange tube 17; the hot water tank 3 is connected to the first heat exchange tube 17 through a pipeline, and a hot water circulation pump 2 is provided on the pipeline.

[0042] Based on Example 1, this Example 9 provides a more preferred structure of the heat exchange mechanism, specifically: the heat exchange mechanism includes a first heat exchange tube 17 arranged in the flue gas channel in the thermal oil furnace 1, a second heat exchange tube 18 connected from the first heat exchange tube 17 and arranged in the generator 6, and a hot water tank 3 connected from the second heat exchange tube 18 and connected to the first heat exchange tube 17; the hot water tank 3 is connected to the first heat exchange tube 17 by a pipeline, and a hot water circulation pump 2 is provided on the pipeline. With such a design, the 95°C hot water in the hot water tank 3 enters the first heat exchange tube 17 through the hot water circulation pump 2 to exchange heat with the flue gas of the thermal oil furnace into 115°C hot water, and the 115°C hot water enters the second heat exchange tube 18 through the pipeline to provide heat for the high-pressure ammonia-rich liquid absorbent in the generator 6 to evaporate high-temperature and high-pressure gaseous ammonia. The high-pressure ammonia-rich liquid absorbent absorbs heat and evaporates high-temperature and high-pressure gaseous ammonia, and the remaining high-pressure ammonia-poor liquid absorbent flows back to the absorber 4 through the pipeline and throttling into low-pressure ammonia-poor liquid absorbent. The 115°C hot water is converted into 95°C hot water again after heat exchange and flows back to the hot water tank 3 through the pipeline, thus forming a cycle, saving energy and water.

[0043] The present invention provides an energy-saving system in an ABS production system. With hot water as a carrier, the waste heat of the flue gas of the thermal oil furnace is used to heat the 95°C hot water to 115°C and send it to the ammonia absorption refrigeration device, which is used as a heat source to drive the refrigeration medium to work. The ammonia absorption refrigeration device reduces the temperature of the refrigerated return water from 0°C to -5°C for users to use; the temperature of the hot water after releasing the heat is reduced to 95°C and returns to the hot water tank for 3 cycles of use by its own residual pressure. The specific process is as follows:

[0044] The flue gas generated by the thermal oil furnace is ~280°C, which heats the 95°C hot water from the hot water tank 3 to 115°C through the first heat exchange tube; the 115°C hot water acts as a carrier to carry ~1860kW of heat (taking -5°C / 0°C chilled water with a cooling capacity of 1000kW as an example) away from the flue gas of the thermal oil furnace to the ammonia absorption refrigeration device for use as a heat source.

[0045] After releasing heat in the generator 6 of the ammonia absorption refrigeration device, the temperature of the 115°C hot water drops to 95°C and returns to the hot water tank 3 by its own residual pressure. The 95°C hot water is pressurized by the hot water circulation pump and sent to the first heat exchange tube in the flue gas channel in the thermal oil furnace and then heated to 115°C by the flue gas, thus forming a hot water circulation system.

[0046] The generator 6 of the ammonia absorption refrigeration device utilizes the heat of 115°C hot water to evaporate the ammonia-rich liquid absorbent on the high-pressure side of the ammonia absorption refrigeration device into high-temperature and high-pressure gaseous ammonia, and at the same time the temperature of the hot water is reduced to 95°C. The gaseous ammonia is condensed by the gaseous ammonia condenser 7 to become high-pressure liquid ammonia. The high-pressure liquid ammonia is throttled by the first throttle valve 7, and its temperature and pressure are reduced. It is evaporated into low-pressure gaseous ammonia in the evaporator 8 on the low-pressure side. At the same time, the temperature of the chilled water in the pipe side of the evaporator 8 is reduced from 0°C to -5°C. The low-pressure gaseous ammonia goes to the absorber 4 to be absorbed by the ammonia-lean liquid absorbent. The liquid absorbent that absorbs ammonia is pressurized by the booster pump and goes to the high-pressure side of the generator 6. A part of the liquid absorbent of the generator 6 is returned to the absorber 4 after throttling for absorbing gaseous ammonia.

[0047] The -5℃ chilled water produced in the evaporator 8 tube pass of the ammonia absorption refrigeration device is delivered to the user. After heat exchange by the user, the temperature of the chilled water rises from -5℃ to 0℃. The 0℃ chilled water flows back to the chilled water tank due to its own residual pressure, and is then pressurized by the chilled water circulation pump and delivered to the ammonia absorption refrigeration device, thus forming a continuous operation of the chilled water circulation system.

[0048] Embodiment 10, as Figure 1As shown, the present invention provides a method for energy-saving system in ABS production system, which uses heat exchange mechanism to replace the heat of high-temperature flue gas in the thermal oil furnace to the generator in the ammonia absorption refrigeration device as a heat source, and the high-pressure ammonia-rich liquid absorbent in the generator absorbs heat and vaporizes into high-temperature and high-pressure gas ammonia. The high-temperature and high-pressure gas ammonia is condensed into high-pressure liquid ammonia and then enters the evaporator to evaporate into low-pressure gas ammonia and is recovered into the generator. The pipeline for supplying chilled water to the condenser passes through the evaporator, and the chilled water in the pipeline is reduced from 0°C to -5°C so as to use 0°C chilled water to provide -5°C chilled water for the condenser.

[0049] The present invention utilizes the waste heat of the flue gas of the thermal oil furnace to heat 95°C hot water to 115°C and sends it to the ammonia absorption refrigeration device, which serves as a heat source to drive the refrigeration medium to work, and reduces the temperature of the chilled return water from 0°C to -5°C for user use; the temperature of the hot water after releasing the heat is reduced to 95°C and returns to the hot water tank for recycling by its own residual pressure.

[0050] The flue gas temperature from the thermal oil boiler is ~280℃, which is heated to ~115℃ by ~95℃ hot water through the first heat exchange tube; the hot water is used as a carrier to bring ~1860kW of heat (taking -5℃ / 0℃ chilled water with 1000kW of cooling capacity as an example) from the flue gas of the thermal oil boiler to the ammonia absorption refrigeration device for use.

[0051] The generator of the ammonia absorption refrigeration device uses the heat of 115℃ hot water to evaporate the ammonia-rich liquid absorbent on the high-pressure side of the ammonia absorption refrigeration device into high-temperature and high-pressure gaseous ammonia. At the same time, the temperature of the hot water is reduced to 95℃. The high-temperature and high-pressure gaseous ammonia is condensed by the condenser to become high-pressure liquid ammonia. The temperature and pressure of the high-pressure liquid ammonia are reduced after throttling and evaporated into low-pressure gaseous ammonia in the evaporator on the low-pressure side of the generator. At the same time, the temperature of the chilled water is reduced from 0℃ to -5℃ for user use. The low-pressure gaseous ammonia goes to the absorber and is absorbed by the ammonia-poor liquid absorbent. The liquid absorbent that absorbs the gaseous ammonia is pressurized by the booster pump and goes to the high-pressure side of the generator. A part of the liquid absorbent of the generator is throttled and refluxed to the absorber for absorbing gaseous ammonia.

[0052] The heat exchange mechanism consists of a hot water tank, a hot water circulation pump, a first heat exchange tube and a second heat exchange tube: after the ammonia absorption refrigeration device releases heat, the hot water with a temperature of 95°C flows back to the hot water tank by its own residual pressure, is pressurized by the hot water circulation pump and sent to the first heat exchange tube, and is then heated to 115°C by the flue gas and sent to the second heat exchange tube as a heat source to drive the refrigeration medium to work.

[0053] The chilled water circulation system is an open circulation system consisting of a normal pressure chilled water tank, a chilled water circulation pump, an evaporator pipe, and a chilled water user (condenser 11 in the devolatilization process of the ABS production system); a closed circulation system may also be used.

[0054] The heat transfer oil furnace system 20 of the present invention comprises a heat transfer oil furnace, a heat transfer oil supply pipe 21 and a heat transfer oil return pipe 22 respectively connected to the heat transfer oil furnace, and a first heat exchange pipe arranged in the flue gas channel of the heat transfer oil furnace. The present invention utilizes the flue gas waste heat in the heat transfer oil furnace in the heat transfer oil furnace system 20 to heat 95°C hot water to 115°C and send it to the ammonia absorption refrigeration device, which is used as a heat source to drive the refrigeration medium to work, and the temperature of the chilled return water is reduced from 0°C to -5°C for users. The waste heat-driven ammonia absorption refrigeration device replaces the electric-driven compression refrigeration unit, which saves a lot of electricity consumption and ensures economy. The temperature of the water return of the ammonia absorption refrigeration device is controlled at -5°C / 0°C to save investment and reduce energy consumption. The temperature of the water return of the heat exchange mechanism is controlled at 115°C / 95°C to save investment. The chilled water circulation system can adopt an open circulation system or a closed circulation system.

[0055] For a 200,000 ton / year emulsion grafting-bulk SAN blending ABS plant, the SAN device uses an electrically driven compression refrigeration unit with a capacity of 1000kW, and its power consumption is ~360kW. The power consumption of the pump of the present invention is ~60kW, and the annual electricity saving is ~2,400,000kWh. The industrial electricity price is 0.6 yuan / kWh, and the present invention is applied to the emulsion grafting-bulk SAN blending and continuous bulk ABS production to save 1.44 million yuan in electricity costs. Therefore, the present invention has a high promotion value and is suitable for vigorous promotion and application.

[0056] Finally, it should be noted that the above embodiments are only preferred embodiments of the present invention to illustrate the technical solution of the present invention, but not to limit it, and certainly not to limit the patent scope of the present invention. Any changes or modifications that have no substantial significance on the main design concept and spirit of the present invention, which solve technical problems consistent with the present invention, should be included in the protection scope of the present invention; in addition, the direct or indirect application of the technical solution of the present invention in other related technical fields should also be included in the patent protection scope of the present invention.

Claims

1. An energy-saving system in an ABS production system, characterized in that: The invention comprises a heat transfer oil furnace (1) for providing heat transfer oil for an emulsion grafting-bulk SAN blending method and a continuous bulk method ABS production system, a condenser (11) in a devolatilization process of the ABS production system, a chilled water tank (10) for providing chilled water for the condenser (11), an ammonia absorption refrigeration device connected between the chilled water tank (10) and the condenser (11) for cooling the chilled water, and a heat exchange mechanism connected to the heat transfer oil furnace (1) and the ammonia absorption refrigeration device respectively for exchanging the heat of flue gas in the heat transfer oil furnace (1) into refrigeration power for the ammonia absorption refrigeration device; The ammonia absorption refrigeration device comprises a generator (6) connected to a heat exchange mechanism and storing a high-pressure ammonia-rich liquid absorbent, an evaporator (8) connected between a chilled water tank (10) and a condenser (11), an absorber (4) connected from the evaporator (8) and connected to the generator (6) and storing ammonia-poor liquid absorbent, and a gas ammonia condenser (7) connected from the generator (6) and connected to the evaporator (8); The heat exchange mechanism comprises a first heat exchange tube (17) arranged in a smoke channel in a heat-conducting oil furnace (1), a second heat exchange tube (18) connected from the first heat exchange tube (17) and arranged in a generator (6), and a hot water tank (3) connected from the second heat exchange tube (18) and connected to the first heat exchange tube (17); the hot water tank (3) and the first heat exchange tube (17) are connected by a pipeline, and a hot water circulation pump (2) is provided on the pipeline.

2. The energy-saving system in an ABS production system according to claim 1, characterized in that: The ammonia condenser (7) and the evaporator (8) are connected by a pipeline, and a first throttle valve (12) is provided on the pipeline.

3. The energy-saving system in an ABS production system according to claim 1, characterized in that: The absorber (4) and the generator (6) are connected by a pipeline, and a booster pump (5) is provided on the pipeline.

4. The energy-saving system in an ABS production system according to claim 1, characterized in that: An ammonia-poor liquid absorbent return pipe (13) is connected between the generator (6) and the absorber (4), and a second throttle valve (14) is provided on the ammonia-poor liquid absorbent return pipe (13).

5. The energy-saving system in an ABS production system according to claim 1, characterized in that: The evaporator (8) is a shell and tube evaporator. The shell side of the evaporator (8) is respectively connected to the gas ammonia condenser (7) and the absorber (4). A chilled water delivery pipe (15) is connected between the chilled water tank (10) and the condenser (11). The tube side of the evaporator (8) is connected to the chilled water delivery pipe (15).

6. The energy-saving system in an ABS production system according to claim 5, characterized in that: A chilled water circulation pump (9) is provided on the chilled water delivery pipe (15).

7. The energy-saving system in an ABS production system according to claim 1, characterized in that: A chilled water return pipe (16) is connected between the chilled water tank (10) and the condenser (11).

8. The method for energy saving system in ABS production system according to any one of claims 1 to 7, characterized in that: The heat of the high-temperature flue gas in the thermal oil furnace is replaced by a heat exchange mechanism to the generator in the ammonia absorption refrigeration device for use as a heat source. The high-pressure ammonia-rich liquid absorbent in the generator absorbs heat and vaporizes into high-temperature and high-pressure gaseous ammonia. The high-temperature and high-pressure gaseous ammonia is condensed into high-pressure liquid ammonia, which is throttled and then enters the evaporator to evaporate into low-pressure gaseous ammonia and is recovered into the generator. The pipeline that supplies chilled water to the condenser reduces the chilled water in it from 0℃ to -5℃ after passing through the evaporator, so as to provide -5℃ chilled water for the condenser.

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