A system for coupling and utilizing semi-coke wastewater

Abstract

The utility model provides a kind of coking wastewater coupling utilization system, belong to chemical production wastewater treatment technical field, it includes solvent recovery column, deaminating tower, water tower, solvent recovery column reboiler, water tower reboiler and ammonia gas processing system, solvent recovery column, deaminating tower and water tower are sequentially communicated from front to back, the top of deaminating tower is communicated with ammonia gas processing system via solvent recovery column reboiler, the top of deaminating tower is also communicated with ammonia gas processing system via water tower reboiler.The utility model discharges high-temperature ammonia gas from the top of deaminating tower as heat source, heats the column still liquid in solvent recovery column reboiler, heats water in water tower reboiler, replaces the existing heat-conducting oil heating mode, simultaneously reduces the quantity of subsequent equipment for cooling ammonia gas, to realize the coupling utilization of heat in high-temperature ammonia gas discharged from deaminating tower, reduce the waste of heat energy.

Description

Technical Field

[0001] This utility model belongs to the field of chemical production wastewater treatment technology, and relates to the treatment technology of semi-coke wastewater, specifically a semi-coke wastewater coupling utilization system. Background Technology

[0002] Semi-coke wastewater, also known as semi-coke wastewater, refers to industrial wastewater generated during the low-rank coal (non-caking coal, weakly caking coal, long-flame coal) dry distillation process (approximately 450-650℃) and the coal gas purification and semi-coke steam quenching processes. Currently, semi-coke production mainly adopts an internal heating low-temperature dry distillation process, using Venturi towers and cyclone plate towers for water washing to remove tar from the coal gas. During the washing of coal tar, a large amount of high-concentration phenol-containing wastewater, i.e., semi-coke wastewater, is generated.

[0003] Existing semi-coke wastewater treatment processes require significant heat sources to heat equipment. For example, using heat transfer oil or lava as heating media to heat solvent recovery towers and water towers necessitates an organic carrier (heat transfer oil or lava) furnace to heat the heat transfer oil or lava. However, the gaseous phase (ammonia) generated at the top of the ammonia removal tower during semi-coke wastewater treatment needs to be liquefied to form liquid ammonia during recovery. Currently, the heat released from ammonia to liquid ammonia is not utilized effectively and is directly cooled and released. This release process requires additional cooling equipment, resulting in high equipment costs and energy waste. Therefore, existing semi-coke wastewater treatment processes suffer from the technical problem of inefficient energy utilization and energy waste. Summary of the Invention

[0004] In view of the technical problem described in the background art, the existing semi-coke wastewater treatment process has the problem of energy not being used rationally, resulting in heat energy waste. In order to address this technical problem, this utility model proposes a semi-coke wastewater coupled utilization system.

[0005] To solve the above-mentioned technical problems, the present invention proposes the following technical solution:

[0006] This utility model discloses a semi-coke wastewater co-utilization system, comprising a solvent recovery tower, an ammonia removal tower, a water tower, a solvent recovery tower reboiler, a water tower reboiler, and an ammonia treatment system. The solvent recovery tower, the ammonia removal tower, and the water tower are connected sequentially from front to back. The top of the ammonia removal tower is connected to the ammonia treatment system via the solvent recovery tower reboiler, and the top of the ammonia removal tower is also connected to the ammonia treatment system via the water tower reboiler.

[0007] Further specifying, the semi-coke wastewater co-utilization system also includes a first pre-separator, a first transfer pump, a second pre-separator, and a second transfer pump. The solvent recovery tower reboiler is connected to the ammonia treatment system in sequence through the first pre-separator and the first transfer pump. The water tower reboiler is connected to the ammonia treatment system in sequence through the second pre-separator and the second transfer pump.

[0008] Further specifying, the ammonia treatment system includes a multi-stage condensation separation unit and an ammonia refining tower, and both the first and second transfer pumps are connected to the ammonia refining tower through the multi-stage condensation separation unit.

[0009] Further defined, the multi-stage condensation and separation unit includes a first-stage condenser, a first-stage separator, a second-stage condenser, a second-stage separator, a third-stage condenser, and a third-stage separator connected sequentially from front to back, wherein the first and second delivery pumps are both connected to the first-stage condenser, and the third-stage separator is connected to the ammonia refining tower.

[0010] Further specifying, the semi-coke wastewater coupling utilization system also includes an extraction tower #1, a deacidification tower, and an extraction tower #2. The extraction tower #1 is connected to a solvent recovery tower via the deacidification tower, and the deammoniation tower is connected to a water tower via the extraction tower #2.

[0011] Further specified, the top of the No. 1 extraction tower is connected to the No. 1 extract tank, and the top of the No. 2 extraction tower is connected to the No. 2 extract tank.

[0012] Furthermore, the semi-coke wastewater co-utilization system also includes a phenol tower connected to the water tower.

[0013] Furthermore, the semi-coke wastewater co-utilization system also includes a saturation tower, which is connected to the No. 1 extraction tower.

[0014] Furthermore, the semi-coke wastewater co-utilization system also includes an oil separator, which is connected to a saturation tower.

[0015] Furthermore, the semi-coke wastewater co-utilization system also includes a light oil separator and a heavy oil separator, with the top of the oil separator connected to the light oil separator and the bottom of the oil separator connected to the heavy oil separator.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1. This utility model discloses a semi-coke wastewater co-utilization system, which connects the top of the deammoniation tower to the ammonia treatment system via a solvent recovery tower reboiler and a water tower reboiler. The high-temperature ammonia gas discharged from the top of the deammoniation tower is used as a heat source to heat the bottom liquid in the solvent recovery tower reboiler and the water in the water tower reboiler, replacing the existing heat transfer oil heating method. At the same time, it reduces the number of subsequent ammonia cooling devices, thereby realizing the co-utilization of heat in the high-temperature ammonia gas discharged from the deammoniation tower, reducing heat energy waste and equipment costs.

[0018] 2. This utility model provides a semi-coke wastewater co-utilization system, which also includes an ammonia treatment system. The ammonia treatment system recovers the ammonia discharged from the deammoniation tower and prepares refined ammonia, thus saving resources.

[0019] 3. The ammonia treatment system of this utility model includes a multi-stage condensation and separation unit, which performs gas-liquid separation and extraction of ammonia through the multi-stage condensation and separation unit, thereby improving the ammonia recovery efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the semi-coke wastewater co-utilization system of this utility model;

[0021] Figure 2 A schematic diagram of an ammonia treatment system;

[0022] Explanation of reference numerals in the attached figures:

[0023] 1-Light oil separator, 2-Heavy oil separator, 3-Oil separator, 4-Saturation tower, 5-1# extraction tower, 6-1# extract tank, 7-Deacidification tower, 8-Solvent recovery tower, 9-Deammoniation tower, 10-2# extraction tower, 11-Water tower, 12-Phenol tower, 13-Solvent recovery tower reboiler, 14-First pre-separator, 15-First transfer pump, 16-Water tower reboiler, 17-Second pre-separator, 18-Second transfer pump, 19-First stage condenser, 20-First stage separator, 21-Second stage condenser, 22-Second stage separator, 23-Third stage condenser, 24-Third stage separator, 25-Ammonia refining tower, 26-2# extract tank. Detailed Implementation

[0024] The technical solution of this utility model will be further explained and described below with reference to the accompanying drawings and embodiments, but this utility model does not include the embodiments described below.

[0025] See Figure 1This utility model proposes a semi-coke wastewater coupled utilization system, which includes a light oil separator 1, a heavy oil separator 2, an oil-water separation tank 3, a saturation tower 4, a No. 1 extraction tower 5, a deacidification tower 7, a solvent recovery tower 8, a deammoniation tower 9, a No. 2 extraction tower 10, a water tower 11, a phenol tower 12, and an ammonia treatment system. The oil-water separation tank 3, saturation tower 4, No. 1 extraction tower 5, deacidification tower 7, solvent recovery tower 8, deammoniation tower 9, No. 2 extraction tower 10, water tower 11, and phenol tower 12 are connected sequentially from front to back. The top of the oil-water separation tank 3 is connected to the light oil separator 1, and the bottom of the oil-water separation tank 3 is connected to the heavy oil separator 2. The top of the No. 1 extraction tower 5 is connected to the No. 1 extract tank 6, and the top of the No. 2 extraction tower 10 is connected to the No. 2 extract tank 26. The semi-coke wastewater first enters the oil separator 3, where it undergoes stratified sedimentation. The upper layer, consisting of light oil, is transported to the light oil separator 1, where it settles and is separated. The lower layer, consisting of heavy oil, is transported to the heavy oil separator 2, where it settles and is separated. A solvent recovery tower reboiler 13 is connected to the bottom of the solvent recovery tower 8, and a water tower reboiler 16 is connected to the bottom of the water tower 11. A wastewater layer is formed in the middle layer of the oil separator 3. The wastewater in the wastewater layer is transported to the saturation tower 4. After sufficient contact and mass transfer with the acidic gas containing hydrogen sulfide in the saturation tower 4, the wastewater is discharged and transported to the No. 1 extraction tower 5. The No. 1 extraction tower 5 is equipped with an extractant (methyl isobutyl ketone), which is also referred to as the solvent below. After the wastewater is fully contacted with the extractant in the No. 1 extraction tower 5, most of the oils and phenols enter the solvent. There is a density difference between the aqueous phase and the extract phase. The extract phase rises and enters the No. 1 extract tank 6. The aqueous phase is collected from the bottom of the No. 1 extraction tower 5 and enters the deacidification tower 7. After deacidification treatment in the deacidification tower 7, acidic gas is formed and discharged from the top of the deacidification tower 7. The bottom liquid of the deacidification tower 7 is collected and enters the solvent recovery tower 8. The extractant (solvent) is recovered in the solvent recovery tower 8. A solvent recovery tower reboiler 13 is installed at the bottom of the solvent recovery tower 8. In the reboiler 13 of the recovery tower, the wastewater containing solvent exchanges heat with high-temperature ammonia gas, causing the temperature of the wastewater containing solvent to rise. The solvent and wastewater are separated and collected separately. After being collected, the wastewater enters the deammoniation tower 9, where it undergoes distillation. The high-temperature ammonia gas generated at the top of the deammoniation tower 9 enters the solvent recovery tower reboiler 13 and the water tower reboiler 16 as heat sources. The aqueous phase formed at the bottom of the deammoniation tower 9 enters the No. 2 extraction tower 10. After being fully contacted with the solvent (methyl isobutyl ketone) in the No. 2 extraction tower 10, the extract phase rises to the top of the No. 2 extraction tower 10 and enters the No. 2 extract tank 26 through the top of the No. 2 extraction tower 10. After being collected, the aqueous phase enters the water tower 11, where it undergoes condensation and separation. The condensed and separated gas phase is collected through the top of the water tower 11, and the liquid phase, as high-phenol-content wastewater, enters the phenol tower 12 for further processing.The reboiler 16 installed at the bottom of the water tower 11 is used to regulate the bottom temperature of the water tower 11 between 101℃ and 109℃.

[0026] The coke wastewater co-utilization system of this utility model also includes a first pre-separator 14, a first transfer pump 15, a second pre-separator 17, and a second transfer pump 18. The solvent recovery tower reboiler 13 is connected to the ammonia treatment system via the first pre-separator 14 and the first transfer pump 15 in sequence, and the water tower reboiler 16 is connected to the ammonia treatment system via the second pre-separator 17 and the second transfer pump 18 in sequence.

[0027] In this invention, the temperature of the high-temperature ammonia gas at the top of the ammonia removal tower 9 is 145℃ and the pressure is 0.5 MPa. The bottom temperature of the solvent recovery tower 8 and the bottom temperature of the water tower 11 are both 105℃, with a temperature difference of up to 30℃. The large temperature difference allows for heat exchange. Therefore, this invention uses the high-temperature ammonia gas as the heating medium for the reboiler 13 of the solvent recovery tower and the reboiler 16 of the water tower, replacing the existing heat transfer oil. This achieves the coupled utilization of the heat in the high-temperature ammonia gas discharged from the ammonia removal tower 9, reducing heat energy waste and equipment costs.

[0028] See Figure 2 The ammonia treatment system includes a multi-stage condensation and separation unit and an ammonia refining tower 25 connected sequentially from front to back. The multi-stage condensation and separation unit includes a multi-stage condenser and a multi-stage separator, which are connected at intervals. After the ammonia is cooled by the condenser, it forms a gas-liquid mixture. The gas-liquid mixture is then separated by the separator to extract the ammonia. The separation efficiency of ammonia is improved through multi-stage condensation and extraction.

[0029] Preferably, in this invention, the multi-stage condensation and separation unit includes a three-stage condenser and a three-stage separator, specifically a first-stage condenser 19, a first-stage separator 20, a second-stage condenser 21, a second-stage separator 22, a third-stage condenser 23, and a third-stage separator 24. The first-stage condenser 19, the first-stage separator 20, the second-stage condenser 21, the second-stage separator 22, the third-stage condenser 23, and the third-stage separator 24 are connected sequentially from front to back. The first-stage condenser 19 is connected to both the first transfer pump 15 and the second transfer pump 18, and is used to receive the gas-liquid mixture containing ammonia from the first transfer pump 15 and the second transfer pump 18. The third-stage separator 24 is connected to the ammonia refining tower 25, and the ammonia discharged from the third-stage separator 24 enters the ammonia refining tower 25 to prepare refined ammonia.

[0030] The working process of the ammonia treatment system in this invention will be explained and described in detail below using a three-stage condenser and a three-stage separator:

[0031] The gas-liquid mixture in the primary condenser 19 exchanges heat with the circulating cooling water. The cooled gas-liquid mixture discharged from the primary condenser 19 enters the primary separator 20, where primary crude ammonia is extracted and discharged. The primary crude ammonia then enters the secondary condenser 21, where it exchanges heat with the circulating cooling water. The cooled gas-liquid mixture discharged from the secondary condenser 21 enters the secondary separator 22, where secondary crude ammonia is extracted and discharged. The secondary crude ammonia then enters the tertiary condenser 23, where it exchanges heat with the circulating cooling water. The cooled gas-liquid mixture discharged from the tertiary condenser 23 enters the tertiary separator 24, where tertiary crude ammonia is extracted and discharged. The tertiary crude ammonia then enters the ammonia refining tower 25, where refined ammonia is prepared.

[0032] This utility model relates to a semi-coke wastewater co-utilization system. The system utilizes the following components: a light oil separator 1, a heavy oil separator 2, an oil separator 3, a saturation tower 4, a No. 1 extraction tower 5, a deacidification tower 7, a solvent recovery tower 8, a deammoniation tower 9, a No. 2 extraction tower 10, a water tower 11, and a phenol tower 12; a primary condenser 19, a primary separator 20, a secondary condenser 21, a secondary separator 22, a tertiary condenser 23, a tertiary separator 24, and an ammonia refining tower 25; and a system where the No. 1 extraction tower 5 is connected to the... The connection pipes between the 1# extract tank 6, the connection pipes between the 2# extract tower 10 and the 2# extract tank 26, the connection pipes between the solvent recovery tower reboiler 13, the first pre-separator 14, the first transfer pump 15 and the ammonia treatment system, and the connection pipes between the water tower reboiler 16, the second pre-separator 17, the second transfer pump 18 and the ammonia treatment system are all conventional technologies and will not be described in detail here.

[0033] The use of thermometers, pressure gauges, and level gauges in related equipment as required by this invention is conventional technology and will not be elaborated upon here.

[0034] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A semi-coke wastewater co-utilization system, characterized in that, The system includes a solvent recovery tower (8), an ammonia removal tower (9), a water tower (11), a solvent recovery tower reboiler (13), a water tower reboiler (16), and an ammonia treatment system. The solvent recovery tower (8), the ammonia removal tower (9), and the water tower (11) are connected sequentially from front to back. The top of the ammonia removal tower (9) is connected to the ammonia treatment system via the solvent recovery tower reboiler (13), and the top of the ammonia removal tower (9) is also connected to the ammonia treatment system via the water tower reboiler (16). The semi-coke wastewater co-utilization system also includes a first pre-separator (14), a first transfer pump (15), a second pre-separator (17), and a second transfer pump (18). The solvent recovery tower reboiler (13) is connected to the ammonia treatment system in sequence through the first pre-separator (14) and the first transfer pump (15). The water tower reboiler (16) is connected to the ammonia treatment system in sequence through the second pre-separator (17) and the second transfer pump (18).

2. The semi-coke wastewater co-utilization system according to claim 1, characterized in that, The ammonia processing system includes a multi-stage condensation separation unit and an ammonia refining tower (25). The first transfer pump (15) and the second transfer pump (18) are both connected to the ammonia refining tower (25) through the multi-stage condensation separation unit.

3. The semi-coke wastewater co-utilization system according to claim 2, characterized in that, The multi-stage condensation and separation unit includes a first-stage condenser (19), a first-stage separator (20), a second-stage condenser (21), a second-stage separator (22), a third-stage condenser (23), and a third-stage separator (24) connected sequentially from front to back. The first delivery pump (15) and the second delivery pump (18) are both connected to the first-stage condenser (19), and the third-stage separator (24) is connected to the ammonia refining tower (25).

4. The semi-coke wastewater co-utilization system according to any one of claims 1-3, characterized in that, The semi-coke wastewater coupling utilization system also includes a No. 1 extraction tower (5), a deacidification tower (7) and a No. 2 extraction tower (10). The No. 1 extraction tower (5) is connected to the solvent recovery tower (8) via the deacidification tower (7), and the deammoniation tower (9) is connected to the water tower (11) via the No. 2 extraction tower (10).

5. The semi-coke wastewater co-utilization system according to claim 4, characterized in that, The top of the No. 1 extraction tower (5) is connected to the No. 1 extract tank (6), and the top of the No. 2 extraction tower (10) is connected to the No. 2 extract tank (26).

6. The semi-coke wastewater co-utilization system according to claim 4, characterized in that, The semi-coke wastewater co-utilization system also includes a phenol tower (12) connected to the water tower (11).

7. The semi-coke wastewater co-utilization system according to claim 4, characterized in that, The semi-coke wastewater co-utilization system also includes a saturation tower (4), which is connected to the No. 1 extraction tower (5).

8. The semi-coke wastewater co-utilization system according to claim 7, characterized in that, The semi-coke wastewater co-utilization system also includes an oil separator (3), which is connected to a saturation tower (4).

9. The semi-coke wastewater co-utilization system according to claim 8, characterized in that, The semi-coke wastewater co-utilization system also includes a light oil separator (1) and a heavy oil separator (2). The top of the oil separator (3) is connected to the light oil separator (1), and the bottom of the oil separator (3) is connected to the heavy oil separator (2).

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