Carbon disulfide cooling system

Abstract

The utility model provides a carbon disulfide cooling system. The carbon disulfide cooling system comprises a first-stage condenser, a second-stage condenser and a third-stage condenser which are arranged at the gas phase outlet end of a sulfur and carbon catcher. The liquid phase output ends of the first-stage condenser and the second-stage condenser are connected with a crude carbon disulfide buffer tank, and the liquid phase output end of the third-stage condenser is connected with a reflux buffer tank. The output end of the reflux buffer tank is connected with a sulfur capture reflux pump, and the sulfur capture reflux pump is connected with the liquid phase input end of the sulfur and carbon capture device through a reflux pipeline. And the outlet end of the crude carbon disulfide buffer tank is provided with a liquid phase recovery pipeline communicated with the separation tower. A material inlet is formed in the side part of the sulfur and carbon capturing device, and external mixed gas enters from the material inlet. A material outlet is also formed in the bottom of the sulfur and carbon capturing device and is used for discharging excessive sulfur. According to the utility model, the energy consumption of the refrigerating machine required by the subsequent three-stage condenser is reduced, the temperature of the gas phase outlet of the sulfur and carbon capturing device is also reduced, and the cooling recovery of CS2 is more facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of carbon disulfide production, in particular to a carbon dioxide cooling system. Background Art

[0002] In the prior art, the production system of carbon disulfide is produced by non-catalytic reaction of coalbed methane and sulfur. The experimental research ensures the continuous and safe process technology, which enables the system to operate for a long time without carbon precipitation, coking and clogging, and obtains a high conversion rate. However, due to the difference in condensation effect, the CS2 content in the non-condensable gas increases, resulting in artificial loss of materials, reduced product yield, and high unit energy consumption caused by tail gas treatment.

[0003] Specifically, the gas phase coming out of the sulfur and carbon capture device (mainly composed of H2S and CS2, with a temperature of 65-80°C) is cooled only through a secondary condenser, resulting in a large amount of cooling required for the last stage of the condenser. One refrigerator cannot meet the requirement and the cooling effect cannot be achieved. However, when two refrigerators are activated, the temperature is too low, and the solubility of H2S in CS2 increases as the temperature decreases, resulting in a substantial increase in the dissolved H2S in the product CS2 in the crude carbon disulfide buffer tank due to the low temperature.

[0004] The products in the crude carbon disulfide are sent to the next process desulfurization tower. The gas phase after desulfurization in the desulfurization tower is cooled and compressed by the hydrogen sulfide compressor to be sent to the next process. Due to the high CS2 concentration in the desulfurization tower, H2S is released in the desulfurization tower, causing the pressure of the desulfurization tower to rise quickly, causing the compressor load to increase, which is not conducive to the long-term use of the compressor. In addition, due to the increase in H2S concentration, the CS2 partial pressure decreases, which is not conducive to the recovery of CS2, and also leads to an increase in the cooling capacity required for cooling the gas phase after desulfurization in the desulfurization tower, further increasing energy consumption. Utility Model Content

[0005] In view of this, the utility model aims to provide a carbon disulfide cooling system to improve the CS2 recovery effect and reduce energy consumption.

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] A carbon disulfide cooling system comprises a primary condenser, a secondary condenser and a tertiary condenser arranged at the gas phase outlet end of a sulfur and carbon trap;

[0008] The liquid phase output ends of the first-stage condenser and the second-stage condenser are connected to a crude carbon disulfide buffer tank, and the liquid phase output end of the third-stage condenser is connected to a reflux buffer tank;

[0009] The output end of the reflux buffer tank is connected to a sulfur capture reflux pump, which is connected to the liquid phase input end of the sulfur and carbon capture device through a reflux pipeline;

[0010] The outlet end of the crude carbon disulfide buffer tank is provided with a liquid phase recovery pipeline connected to an external desulfurization tower;

[0011] The side of the sulfur and carbon capture device is provided with a material inlet, and the external mixed gas enters from the material inlet;

[0012] A material outlet is also provided at the bottom of the sulfur and carbon trap, and the material outlet is used to discharge excess sulfur.

[0013] Further, the sulfur and carbon capture device includes a first condensation chamber and a second condensation chamber;

[0014] The reflux pipeline includes a first reflux pipeline and a second reflux pipeline connected to the first reflux pipeline;

[0015] The first return pipe is connected to the first condensing chamber, and the second return pipe is connected to the second condensing chamber.

[0016] Furthermore, a first valve is provided on the first return pipeline, and a second valve is provided on the second return pipeline.

[0017] Furthermore, the gas phase outlet of the three-stage condenser is provided with a tail gas recovery pipeline for recovering tail gas.

[0018] Furthermore, a first gas phase pipeline is provided between the first-stage condenser and the second-stage condenser, and a second gas phase pipeline is provided between the second-stage condenser and the third-stage condenser;

[0019] A third gas phase pipeline is provided between the sulfur and carbon capture device and the primary condenser.

[0020] Furthermore, the third-stage condenser is provided with a circulating gas outlet, and a fourth gas phase pipeline connected to the circulating gas outlet and the sulfur and carbon capture device is provided.

[0021] Furthermore, the sulfur and carbon capture devices are respectively provided with a crude carbon disulfide condenser and a hydrogen sulfide heat exchanger;

[0022] The first condensation chamber is arranged in the crude carbon disulfide condenser, and the second condensation chamber is arranged in the hydrogen sulfide heat exchanger;

[0023] The outlet of the hydrogen sulfide heat exchanger is provided with a hydrogen sulfide recovery pipeline connected to an external sulfur recovery device;

[0024] The fourth gas phase pipeline is connected to the inlet of the hydrogen sulfide heat exchanger.

[0025] Furthermore, a steam coil is provided at the bottom of the sulfur and carbon trap, and a steam inlet and a steam outlet are provided on the sulfur and carbon trap.

[0026] The steam coils are used to heat the sulfur in the liquid phase.

[0027] Furthermore, circulating water is used in the primary condenser, and the temperature of the circulating water is in the range of 20 to 30°C;

[0028] The secondary condenser uses low-temperature water, and the temperature of the low-temperature water ranges from 5 to 8°C;

[0029] The three-stage condenser uses cooling water, and the temperature of the cooling water ranges from -20 to -25°C.

[0030] Compared with the prior art, the utility model has the following advantages:

[0031] The carbon disulfide cooling system of the utility model performs the first step of cooling and recovery by setting a first-stage condenser, and performs the second step of cooling and recovery by using a second-stage condenser. At this time, the cooling and recovery of CS2 reaches more than 80%. The CS2 recovered by the first-stage condenser and the second-stage condenser enters the crude carbon disulfide buffer tank, and is sent to the desulfurization tower of the next process through the liquid phase recovery pipeline. During the reaction process of the desulfurization tower, the temperature of the recovered liquid phase is high and the H2S dissolution is small, thereby reducing the load of the desulfurization tower and the hydrogen sulfide compressor, and increasing the carbon disulfide recovery rate by about 2%.

[0032] In addition, due to the two pre-cooling of the primary condenser and the secondary condenser, the energy consumption of the refrigerator required for the subsequent tertiary condenser can be reduced. The remaining CS2 is recovered through the tertiary condenser, and the CS2 with a lower recovered temperature enters the reflux buffer tank. The sulfur capture reflux pump transports the low-temperature CS2 to the sulfur and carbon capture device through the reflux pipeline, thereby reducing the gas phase outlet temperature of the sulfur and carbon capture device, which is more conducive to the cooling and recovery of CS2.

[0033] In addition, by connecting the fourth gas phase pipeline to the inlet of the hydrogen sulfide heat exchanger, the low-temperature gas phase in the three-stage condenser can be returned to the sulfur and carbon capture device for heat exchange cooling, further reducing the gas phase outlet temperature of the sulfur and carbon capture device, which is beneficial to the cooling recovery of CS2. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0035] Figure 1 This is a schematic diagram of the process flow of the carbon disulfide cooling system described in an embodiment of the utility model.

[0036] Description of reference numerals:

[0037] 1. Sulfur and carbon capture device; 2. First-stage condenser; 3. Second-stage condenser; 4. Third-stage condenser; 5. Crude carbon disulfide buffer tank; 6. Reflux buffer tank; 7. Sulfur capture reflux pump; 8. First reflux pipeline; 9. Second reflux pipeline; 10. Liquid phase recovery pipeline; 11. First valve; 12. Second valve; 13. Tail gas recovery pipeline; 14. First gas phase pipeline; 15. Second gas phase pipeline; 16. Third gas phase pipeline; 17. Fourth gas phase pipeline; 18. Hydrogen sulfide recovery pipeline;

[0038] 101. Gas phase outlet; 102. Material inlet; 103. Material outlet; 104. Crude carbon disulfide condenser; 105. Hydrogen sulfide heat exchanger; 106. Steam coil; 107. Steam inlet; 108. Steam outlet; 401. Circulating gas outlet. DETAILED DESCRIPTION

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0040] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "back" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installation", "connection", "connection", and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0042] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0043] The present embodiment relates to a carbon disulfide cooling system, which includes a primary condenser 2, a secondary condenser 3 and a tertiary condenser 4 arranged at the gas phase outlet 101 end of the sulfur and carbon capture device 1. The liquid phase output ends of the primary condenser 2 and the secondary condenser 3 are connected to a crude carbon disulfide buffer tank 5, and the liquid phase output end of the tertiary condenser 4 is connected to a reflux buffer tank 6. The output end of the reflux buffer tank 6 is connected to a sulfur capture reflux pump 7, and the sulfur capture reflux pump 7 is connected to the liquid phase input end of the sulfur and carbon capture device 1 through a reflux pipeline.

[0044] In addition, the outlet end of the crude carbon disulfide buffer tank 5 is provided with a liquid phase recovery pipeline 10 connected to the separation tower. A material inlet 102 is provided on the side of the sulfur and carbon capture device 1, and the external mixed gas enters from the material inlet 102. A material outlet 103 is also provided at the bottom of the sulfur and carbon capture device 1, and the material outlet 103 is used to discharge excess sulfur.

[0045] The carbon disulfide cooling system of this embodiment is provided with a primary condenser 2 for the first step of cooling and recovery, and a secondary condenser 3 for the second step of cooling and recovery. At this time, the cooling and recovery of CS2 reaches more than 80%. The CS2 recovered by the primary condenser 2 and the secondary condenser 3 enters the crude carbon disulfide buffer tank 5 and is sent to the desulfurization tower of the next process through the liquid phase recovery pipeline 10. During the reaction process of the desulfurization tower, the temperature of the recovered liquid phase is high and less H2S is dissolved, thereby reducing the load of the desulfurization tower and the hydrogen sulfide compressor, and increasing the carbon disulfide recovery rate by about 2%.

[0046] In addition, due to the two pre-cooling of the primary condenser 2 and the secondary condenser 3, the energy consumption of the refrigerator required for the subsequent tertiary condenser 4 can be reduced. The remaining CS2 is recovered through the tertiary condenser 4, and the CS2 with a lower recovered temperature enters the reflux buffer tank 6. The sulfur capture reflux pump 7 transports the low-temperature CS2 to the sulfur and carbon capture device 1 through the reflux pipeline, thereby reducing the temperature of the gas phase outlet 101 of the sulfur and carbon capture device 1, which is more conducive to the cooling and recovery of CS2.

[0047] Based on the above overall description, an exemplary structure of the carbon disulfide cooling system of this embodiment is as follows: Figure 1 As shown, the carbon disulfide cooling system of this embodiment is used for non-catalytic production of carbon disulfide by pressurizing coalbed methane.

[0048] Specifically, after the pressure of the coalbed methane is stabilized in the buffer tank and accurately measured, it is mixed with the liquid sulfur (in a certain proportion with the coalbed methane, with excess sulfur) from the sulfur recovery unit and enters the heating furnace. In the heating furnace, it is in an intense fluidized state and the liquid sulfur is vaporized. The gaseous sulfur and coalbed methane are heated to 700°C, and a partial chemical reaction is carried out in the furnace. The mixed gas from the heating furnace enters the adiabatic reactor to continue the reaction. After the reaction is completed, the process gas enters the sulfur cooler of the refining part. After the mixed gas reacted in the reactor, part of the sulfur is condensed after being cooled by the sulfur condenser, and the remaining sulfur is condensed with the gas phase, that is, the above-mentioned material, into the sulfur and carbon capture device 1, and the sulfur settles to the bottom of the tower.

[0049] Preferably, the sulfur and carbon capture device 1 includes a first condensation chamber and a second condensation chamber, the reflux pipeline includes a first reflux pipeline 8 and a second reflux pipeline 9 connected to the first reflux pipeline 8, the first reflux pipeline 8 is connected to the first condensation chamber, and the second reflux pipeline 9 is connected to the second condensation chamber.

[0050] After the sulfur capture reflux pump 7 is started, the cooling liquid phase in the reflux buffer tank 6 is transported to the first condensation chamber and the second condensation chamber. The cooling liquid phase washes and cools the gaseous materials in the first condensation chamber and the second condensation chamber respectively, which not only plays a role in heat recycling and reduces energy demand, but also reduces the gas phase temperature at the outlet of the sulfur and carbon capture device 1.

[0051] Furthermore, if Figure 1 As shown, a first valve 11 is provided on the first return line 8, and a second valve 12 is provided on the second return line 9. The first valve 11 and the second valve 12 are flow regulating valves to control the flow of the cooling liquid phase to ensure the gas phase cooling effect.

[0052] In addition, a tail gas recovery pipeline 13 for recovering tail gas is provided at the gas phase outlet 101 of the third-stage condenser 4. The tail gas recovery pipeline 13 leads to the tail gas treatment equipment for treatment and then discharges the tail gas in compliance with the emission standards.

[0053] In this embodiment, Figure 1 As shown, a first gas phase pipeline 14 is provided between the primary condenser 2 and the secondary condenser 3, a second gas phase pipeline 15 is provided between the secondary condenser 3 and the tertiary condenser 4, and a third gas phase pipeline 16 is provided between the sulfur and carbon capture device 1 and the primary condenser 2. The primary condenser 2, the secondary condenser 3, and the tertiary condenser 4 are arranged in series, and the gas phase output from the gas phase outlet 101 of the sulfur and carbon capture device 1 is cooled three times, and the liquid phase after condensation by the primary condenser 2 and the secondary condenser 3 enters the crude carbon disulfide buffer tank 5 and is transported to the desulfurization tower of the next process. The liquid phase condensed from the tertiary condenser 4 enters the sulfur and carbon capture device 1 through the sulfur capture reflux pump 7.

[0054] Furthermore, the third-stage condenser 4 is provided with a circulating gas outlet 401, and a fourth gas phase pipeline 17 is provided between the circulating gas outlet 401 and the sulfur and carbon capture device 1. The gas phase condensed by the third-stage condenser 4 is recycled to the sulfur and carbon capture device 1 through the fourth gas phase pipeline 17, realizing energy recovery and utilization.

[0055] Preferably, a crude carbon disulfide condenser 104 and a hydrogen sulfide heat exchanger 105 are respectively provided in the sulfur and carbon capture device 1. The first condensation chamber is provided in the crude carbon disulfide condenser 104, and the second condensation chamber is provided in the hydrogen sulfide heat exchanger 105. A hydrogen sulfide recovery pipeline 18 connected to an external sulfur recovery device is provided at the outlet of the hydrogen sulfide heat exchanger 105. The fourth gas phase pipeline 17 is connected to the inlet of the hydrogen sulfide heat exchanger 105.

[0056] By connecting the fourth gas phase pipeline 17 to the inlet of the hydrogen sulfide heat exchanger 105, the low-temperature gas phase in the tertiary condenser 4 can be returned to the sulfur and carbon trap 1 for heat exchange cooling, further reducing the gas phase outlet 101 temperature of the sulfur and carbon trap 1, which is beneficial to the cooling recovery of CS2.

[0057] In addition, a steam coil 106 is provided at the bottom of the sulfur and carbon trap 1, and a steam inlet 107 and a steam outlet 108 are provided on the sulfur and carbon trap 1. The steam coil 106 is used to heat the sulfur in the liquid phase. The steam inlet of the steam coil 106 is heated by 2.2Mpa steam, and the temperature of the tower bottom is controlled at 150-180°C to evaporate the carbon disulfide in the sulfur. The material outlet 103 of the tower bottom of the sulfur and carbon trap 1 is connected to an external flash intermediate tank, and the excess sulfur dissolved with carbon disulfide flashes in the flash tank, and the flashed carbon disulfide goes to the desulfurization tower.

[0058] Preferably, circulating water is used in the primary condenser 2, and the temperature of the circulating water is between 20 and 30° C. Low-temperature water is used in the secondary condenser 3, and the temperature of the low-temperature water is between 5 and 7° C. Cooling water is used in the tertiary condenser 4, and the temperature of the cooling water is between -25 and -20° C.

[0059] The carbon disulfide cooling system described in this embodiment improves the cooling heat recovery rate of CS2 by providing a primary condenser 2 for the first step of cooling heat recovery and a secondary condenser 3 for the second step of cooling heat recovery. The CS2 recovered by the primary condenser 2 and the secondary condenser 3 enters the crude carbon disulfide buffer tank 5 and is sent to the desulfurization tower of the next process through the liquid phase recovery pipeline 10. During the reaction process in the desulfurization tower, the temperature of the recovered liquid phase is high and less H2S is dissolved, thereby reducing the load of the desulfurization tower and the hydrogen sulfide compressor and improving the carbon disulfide recovery rate.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A carbon disulfide cooling system, characterized in that: It comprises a primary condenser (2), a secondary condenser (3) and a tertiary condenser (4) which are arranged at the gas phase outlet (101) end of the sulfur and carbon capture device (1); The liquid phase output ends of the first-stage condenser (2) and the second-stage condenser (3) are connected to a crude carbon disulfide buffer tank (5), and the liquid phase output end of the third-stage condenser (4) is connected to a reflux buffer tank (6); The output end of the reflux buffer tank (6) is connected to a sulfur-capturing reflux pump (7), and the sulfur-capturing reflux pump (7) is connected to the liquid phase input end of the sulfur-capturing and carbon-capturing device (1) through a reflux pipeline; The outlet end of the crude carbon disulfide buffer tank (5) is provided with a liquid phase recovery pipeline (10) connected to an external desulfurization tower; The sulfur and carbon capture device (1) is provided with a material inlet (102) on the side thereof, and the external mixed gas enters through the material inlet (102); The bottom of the sulfur and carbon trap (1) is also provided with a material outlet (103), and the material outlet (103) is used to discharge excess sulfur.

2. The carbon disulfide cooling system according to claim 1, characterized in that: The sulfur and carbon capture device (1) comprises a first condensation chamber and a second condensation chamber; The return pipeline comprises a first return pipeline (8) and a second return pipeline (9) connected to the first return pipeline (8); The first return pipe (8) is connected to the first condensation chamber, and the second return pipe (9) is connected to the second condensation chamber.

3. The carbon disulfide cooling system according to claim 2, characterized in that: The first return pipeline (8) is provided with a first valve (11), and the second return pipeline (9) is provided with a second valve (12).

4. The carbon disulfide cooling system according to claim 3, characterized in that: The gas phase outlet (101) of the three-stage condenser (4) is provided with a tail gas recovery pipeline (13) for recovering tail gas.

5. The carbon disulfide cooling system according to claim 4, characterized in that: A first gas phase pipeline (14) is provided between the first-stage condenser (2) and the second-stage condenser (3), and a second gas phase pipeline (15) is provided between the second-stage condenser (3) and the third-stage condenser (4); A third gas phase pipeline (16) is provided between the sulfur and carbon trap (1) and the primary condenser (2).

6. The carbon disulfide cooling system according to claim 4, characterized in that: The third-stage condenser (4) is also provided with a circulating gas outlet (401), and a fourth gas phase pipeline (17) communicating with the circulating gas outlet (401) and the sulfur and carbon trap (1) is provided between the circulating gas outlet (401).

7. The carbon disulfide cooling system according to claim 6, characterized in that: The sulfur and carbon capture device (1) is provided with a crude carbon disulfide condenser (104) and a hydrogen sulfide heat exchanger (105); The first condensation chamber is disposed in the crude carbon disulfide condenser (104), and the second condensation chamber is disposed in the hydrogen sulfide heat exchanger (105); The outlet of the hydrogen sulfide heat exchanger (105) is provided with a hydrogen sulfide recovery pipeline (18) connected to an external sulfur recovery device; The fourth gas phase pipeline (17) is connected to the inlet of the hydrogen sulfide heat exchanger (105).

8. The carbon disulfide cooling system according to claim 7, characterized in that: The bottom of the sulfur and carbon trap (1) is provided with a steam coil (106), and the sulfur and carbon trap (1) is provided with a steam inlet (107) and a steam outlet (108). The steam coil (106) is used to heat the sulfur in the liquid phase.

9. The carbon disulfide cooling system according to claim 1, characterized in that: The primary condenser (2) uses circulating water, and the temperature of the circulating water is in the range of 20 to 30° C.; The secondary condenser (3) uses low-temperature water, and the temperature of the low-temperature water ranges from 5 to 7°C; The third-stage condenser (4) uses cooling water, and the temperature of the cooling water ranges from -25 to -20°C.

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