A high-temperature and high-pressure steam extraction dechlorination system for high-chlorine waste

Abstract

The present invention belongs to the field of environmental protection technology and specifically relates to a high-temperature, high-pressure steam extraction and dechlorination system for high-chloride waste. The system comprises a high-chloride waste pretreatment unit, a high-chloride waste transfer-extraction unit, and a low-chloride waste collection unit. The high-chloride waste transfer-extraction unit includes a first transfer assembly, a second transfer assembly, a steam extraction assembly, and an extrusion assembly. The first transfer assembly includes a first transfer filter cloth, the second transfer assembly includes a second transfer filter cloth, and the steam extraction assembly includes a high-temperature, high-pressure steam injection device. The system extracts chloride ions through high-temperature, high-pressure steam extraction, and then extrudes the chlorine-containing wastewater for centralized collection and discharge, thereby reducing the chlorine content in the high-chloride waste.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental protection, and in particular relates to a high-temperature and high-pressure steam extraction and dechlorination system for high-chlorine waste. Background Art

[0002] Since its inception, the ammonia-soda process has been widely used in large-scale industrial production of soda ash. The discharge of alkaline slag liquid is inherent to this process. In the industry, the solid slag with main components such as calcium carbonate and sodium chloride is usually called ammonia-soda white mud (commonly known as soda ash slag, which is different from the hazardous waste alkaline slag formed in the manufacturing process of basic chemical raw materials such as sodium hydroxide and potassium hydroxide). If this high-chloride waste is not properly disposed of, it will cause serious pollution to the environment.

[0003] Currently, existing ammonia-soda production facilities are primarily concentrated in Europe, where discharge policies are relatively lax, primarily through long pipelines to deep sea or secure storage with soil covering and greening. There is no literature on large-scale resource utilization. The vast majority of my country's white mud resources remain underutilized due to their limited economic value. Storage can only be achieved through damming and storage, a common problem that has plagued the industry for many years.

[0004] Many beneficial studies conducted at home and abroad have shown that the development and utilization potential of white mud resources is large and can be widely used in multiple industries. However, due to the long-standing differences in the understanding of white mud resources themselves, and the presence of high concentrations of soluble chloride salts in white mud, which may cause cementitious materials to absorb moisture and bloom, structural corrosion, or reduced product strength, the market's low acceptance of white mud and its derivatives has limited the development and large-scale promotion and application of white mud resources. Common chlorides generally have high solubility and their solubility characteristics cannot be significantly changed through ion replacement. Measures such as ion precipitation, complexation, or conversion to gaseous HCl escape are costly and unsuitable for large-scale industrial applications. Therefore, it is necessary to reduce the chlorine content of white mud through technically and economically feasible measures and to properly dispose of chlorine-containing waste liquids, so as to accelerate the large-scale reduction of white mud solid residues and achieve scientific recycling of resources. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste.

[0006] The present invention is implemented in this way, providing a high-chlorine waste high-temperature and high-pressure steam extraction dechlorination system, including a high-chlorine waste pretreatment unit, a high-chlorine waste transmission-extraction unit and a low-chlorine waste collection unit, the high-chlorine waste transmission-extraction unit includes a first transmission component, a second transmission component, a steam extraction component and an extrusion component, the first transmission component includes a first transmission filter cloth, the second transmission component includes a second transmission filter cloth, the steam extraction component includes a high-temperature and high-pressure steam injection device, the outlet of the high-chlorine waste pretreatment unit is located above one end of the first transmission filter cloth, and one end of the second transmission filter cloth is located above the high-chlorine waste pretreatment unit. The outlet of the processing unit is close to the upper side of the material conveying direction of the first conveying filter cloth. After a distance, it contacts and presses the first conveying filter cloth, and then separates from the first conveying filter cloth after another distance. At the position where the second conveying filter cloth and the first conveying filter cloth are pressed, several steam nozzles of high-temperature and high-pressure steam injection devices are set. Before separation, the second conveying filter cloth and the first conveying filter cloth pass between the extrusion components. The low-chlorine waste collection unit includes a scraper and a low-chlorine waste collection bin. After the second conveying filter cloth is separated from the first conveying filter cloth, it contacts a scraper respectively. The outlet between the two scrapers is located above the low-chlorine waste collection bin.

[0007] Preferably, the first conveying assembly further includes a plurality of first conveying wheels, and the second conveying assembly further includes a plurality of second conveying wheels, one end of the first conveying filter cloth is sleeved on a first conveying wheel, and one end of the second conveying filter cloth is sleeved on a second conveying wheel, and the upper side of the position where the first conveying filter cloth and the second conveying filter cloth just contact each other bypasses a second conveying wheel and turns upward, and the position where the first conveying filter cloth and the second conveying filter cloth are pressed alternately bypasses a plurality of first conveying wheels and second conveying wheels, and finally passes through the extrusion assembly, and the first conveying filter cloth and the second conveying filter cloth are respectively turned and separated by a first conveying wheel and a second conveying wheel to form a circular rotation; at the position where the first conveying wheel and the second conveying wheel are alternately arranged, the pressing position of the first conveying filter cloth and the second conveying filter cloth forms multiple pairs of vertical parallel sections, and the steam nozzle is a bidirectional nozzle, and a steam nozzle is arranged between each pair of vertical parallel sections before the last pair of vertical parallel sections, and the extrusion assembly is arranged on both sides of the last pair of vertical parallel sections.

[0008] Further preferably, after the contact position of the first transfer filter cloth and the second transfer filter cloth is turned, an acute angle is formed between the first transfer filter cloth and the second transfer filter cloth before the turning, and a steam nozzle is also provided between the second transfer filter cloth before and after the turning.

[0009] Further preferably, the extrusion assembly includes two pairs of extrusion plates and an extrusion control unit, and the two extrusion plates in each pair of extrusion plates are respectively arranged on both sides of the two vertical parallel sections of the last pair of vertical parallel sections at the compression positions of the first conveying filter cloth and the second conveying filter cloth, and the two pairs of extrusion plates are connected to the extrusion control unit to control the two pairs of extrusion plates to extrude the vertical parallel sections.

[0010] Further preferably, one of the first transmission wheels is a first tensioning wheel, and one of the second transmission wheels is a second tensioning wheel.

[0011] More preferably, a backflushing water device is further included, and a backflushing water nozzle of the backflushing water device is provided at the position after the first transmission filter cloth and the second transmission filter cloth are separated.

[0012] Preferably, a chlorine-containing liquid collection pool is provided below the first conveying assembly, the second conveying assembly and the steam extraction assembly, and an outlet of the chlorine-containing liquid collection pool is connected to a chlorine-containing liquid treatment and recovery system.

[0013] It is further preferred that the chlorine-containing liquid treatment and recovery system includes a chlorine-containing liquid concentration unit, a calcium-aluminum precipitation unit, a Freund's salt collection unit and a purified water recovery unit, the outlet of the chlorine-containing liquid collection tank is connected to the chlorine-containing liquid concentration unit, the high-chloride wastewater outlet of the chlorine-containing liquid concentration unit is connected to the calcium-aluminum precipitation unit, one end of the outlet of the calcium-aluminum precipitation unit is connected to the Freund's salt collection unit, and the other end is connected to the purified water recovery unit, and the concentrated reuse water outlet of the chlorine-containing liquid concentration unit is also connected to the purified water recovery unit.

[0014] Preferably, the high-chloride waste pretreatment unit comprises a high-chloride coarse material storage bin, a wet grinding unit and a high-chloride fine material storage bin connected in sequence, and the lower end outlet of the high-chloride fine material storage bin is located above the first conveying filter cloth.

[0015] Compared with the prior art, the advantages of the present invention are:

[0016] A high-temperature and high-pressure steam extraction and dechlorination system for high-chlorine waste is provided. Chloride ions are extracted by high-temperature and high-pressure steam extraction, and chlorine-containing wastewater is collected and discharged in a centralized manner through extrusion, thereby reducing the chlorine content in the high-chlorine waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural diagram of the high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste provided by the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] refer to Figure 1The present invention provides a high-temperature and high-pressure steam extraction and dechlorination system for high-chlorine waste, comprising a high-chlorine waste pretreatment unit, a high-chlorine waste conveying-extraction unit and a low-chlorine waste collection unit. The high-chlorine waste conveying-extraction unit comprises a first conveying component, a second conveying component, a steam extraction component and an extrusion component. The first conveying component comprises a first conveying filter cloth 18, the second conveying component comprises a second conveying filter cloth 19, the steam extraction component comprises a high-temperature and high-pressure steam injection device, the outlet of the high-chlorine waste pretreatment unit is located above one end of the first conveying filter cloth 18, and one end of the second conveying filter cloth 19 is located at the outlet of the high-chlorine waste pretreatment unit near the first conveying filter cloth 1 8 is above the side of the material conveying direction, contacts and presses with the first conveying filter cloth 18 after a distance, and separates from the first conveying filter cloth 18 after another distance. At the position where the second conveying filter cloth 19 and the first conveying filter cloth 18 are pressed, a plurality of steam nozzles 9 of high-temperature and high-pressure steam injection devices are arranged. Before separation, the second conveying filter cloth 19 and the first conveying filter cloth 18 pass between the extrusion components. The low-chlorine waste collection unit includes a scraper 10 and a low-chlorine waste collection bin 12. After the second conveying filter cloth 19 is separated from the first conveying filter cloth 18, it contacts with a scraper 10 respectively. The outlet between the two scrapers 10 is located above the low-chlorine waste collection bin 12.

[0020] When dechlorination treatment is performed on high-chlorine waste (such as ammonia-soda white mud) by the present invention, the high-chlorine waste is pretreated by the high-chlorine waste pretreatment unit, mainly for processing coarse particles into fine particles and increasing the humidity of the high-chlorine waste. The high-chlorine waste coming out of the high-chlorine waste pretreatment unit is discharged onto the first conveying filter cloth 18. The first conveying filter cloth 18 and the second conveying filter cloth 19 are industrial filter cloths. Since the high-chlorine waste is in a wet state, a small amount of water dissolved in chlorine will fall from the filter cloth during transportation. The high-chlorine waste is discharged onto the first conveying filter cloth 18. After being transported for a distance, it is pressed between the second transfer filter cloth 19 and then passes through the area where the steam nozzle 9 is located along with the two filter cloths. The steam nozzle 9 sprays high-temperature and high-pressure steam to the two filter cloths, increasing the water content in the high-chloride waste and dissolving the chloride ions in the water. The water with dissolved chloride ions is then squeezed out by the pressurizing component. Finally, the first transfer filter cloth 18 and the second transfer filter cloth 19 are separated, and each passes through a scraper 10 to scrape the low-chloride waste on the filter cloth and fall into the low-chloride waste collection bin 12, completing the dechlorination process of the high-chloride waste.

[0021] For reasonable arrangement, as an improvement of the technical solution, the first conveying assembly further includes a plurality of first conveying wheels 13, and the second conveying assembly further includes a plurality of second conveying wheels 7. One end of the first conveying filter cloth 18 is sleeved on a first conveying wheel 13, and one end of the second conveying filter cloth 19 is sleeved on a second conveying wheel 7. The upper side of the position where the first conveying filter cloth 18 and the second conveying filter cloth 19 just contact each other bypasses a second conveying wheel 7 and turns upward. The position where the first conveying filter cloth 18 and the second conveying filter cloth 19 are pressed alternately bypasses a plurality of first conveying wheels 13 and second conveying wheels 7, and finally passes through the extrusion assembly. The first conveying filter cloth 18 and the second conveying filter cloth 19 are then turned and separated by a first conveying wheel 13 and a second conveying wheel 7 respectively, forming a circular rotation; at the position where the first conveying wheel 13 and the second conveying wheel 7 are alternately arranged, the pressing position of the first conveying filter cloth 18 and the second conveying filter cloth 19 forms multiple pairs of vertical parallel sections, and the steam nozzle 9 is a bidirectional nozzle. A steam nozzle 9 is arranged between each pair of vertical parallel sections before the last pair of vertical parallel sections, and the extrusion assembly is arranged on both sides of the last pair of vertical parallel sections.

[0022] The first conveying filter cloth 18 and the second conveying filter cloth 19 are driven by the first conveying wheel 13 and the second conveying wheel 7 to rotate respectively, pass through the area where the steam nozzle 9 is located and the area where the extrusion assembly is located, and steam is generated by the steam generating unit and sprayed to both sides through the steam nozzle 9. The high temperature and high pressure increase the solubility of chloride ions, so that the chloride ions in the high-chloride waste are dissolved in the water.

[0023] In order to further increase the moisture content in the high-chlorine waste, as an improvement to the technical solution, after the contact position of the first transfer filter cloth 18 and the second transfer filter cloth 19 is turned, an acute angle is formed between the first transfer filter cloth 18 and the second transfer filter cloth 19 before the turning, and a steam nozzle 9 is also provided between the second transfer filter cloth 19 before and after the turning.

[0024] As a specific implementation method of the extrusion assembly, the extrusion assembly includes two pairs of extrusion plates 11 and an extrusion control unit. The two extrusion plates 11 in each pair of extrusion plates 11 are respectively arranged on both sides of the two vertical parallel sections of the last pair of vertical parallel sections at the compression position of the first conveying filter cloth 18 and the second conveying filter cloth 19. The two pairs of extrusion plates 11 are connected to the extrusion control unit to control the two pairs of extrusion plates to extrude the vertical parallel sections.

[0025] When high-chloride waste containing a large amount of dissolved chloride ion water passes through two pairs of extrusion plates 11, the extrusion control unit controls the extrusion plates 11 to move closer to each other, extruding the waste, and the moisture in the waste is squeezed out. In order to pressurize cleanly, multiple pairs of extrusion plates 11 can be set. Two pairs are set in this application.

[0026] In order to keep the first transmission filter cloth 18 and the second transmission filter cloth 19 in a compressed state to ensure the transportation of high-chlorine waste, as an improvement, one of the first transmission wheels 13 is a first tensioning wheel 6, and one of the second transmission wheels 7 is a second tensioning wheel 1.

[0027] After the scraper 10 scrapes the dehydrated low-chloride waste from the filter cloth, in order to clean the filter cloth, as an improvement, a backwashing water device is also included, and a backwashing water nozzle 2 of the backwashing water device is provided at the position after the first transmission filter cloth 18 and the second transmission filter cloth 19 are separated.

[0028] In order to treat the chlorine-containing liquid, a chlorine-containing liquid collection tank 8 is provided below the first conveying assembly, the second conveying assembly and the steam extraction assembly. The outlet of the chlorine-containing liquid collection tank 8 is connected to a chlorine-containing liquid treatment and recovery system.

[0029] As a specific implementation method of the chlorine-containing liquid treatment and recovery system, the chlorine-containing liquid treatment and recovery system includes a chlorine-containing liquid concentration unit 14, a calcium-aluminum precipitation unit 15, a Freund's salt collection unit 16 and a purified water recovery unit 17. The outlet of the chlorine-containing liquid collection tank 8 is connected to the chlorine-containing liquid concentration unit 14, the high-chloride wastewater outlet of the chlorine-containing liquid concentration unit 14 is connected to the calcium-aluminum precipitation unit 15, one end of the outlet of the calcium-aluminum precipitation unit 15 is connected to the Freund's salt collection unit 16, and the other end is connected to the purified water recovery unit 17, and the concentrated reuse water outlet of the chlorine-containing liquid concentration unit 14 is also connected to the purified water recovery unit 17.

[0030] During the treatment process, the chlorine-containing liquid is discharged into the chlorine-containing liquid concentration unit 14 through the chlorine-containing liquid collection tank 8 for concentration to form a high-chloride liquid. The high-chloride liquid is subjected to precipitation and dechlorination treatment in the calcium-aluminum precipitation unit 15 to produce Freund's salt which is collected in the Freund's salt collection unit 16 to realize resource utilization. The water after the chlorine is precipitated is discharged into the purified water recovery unit 17, and the water concentrated in the chlorine-containing liquid concentration unit 14 is also discharged into the purified water recovery unit 17 for recycling.

[0031] As a specific implementation of the high-chlorine waste pretreatment unit, the high-chlorine waste pretreatment unit includes a high-chlorine coarse material storage bin 3, a wet grinding unit 4 and a high-chlorine fine material storage bin 5 connected in sequence, and the lower end outlet of the high-chlorine fine material storage bin 5 is located above the first conveying filter cloth 18.

[0032] The collected high-chloride coarse material is stored in the high-chloride coarse material storage bin 3, and is wet-ground by the wet-grinding unit 4 to form fine particles with a certain humidity, which are then stored in the high-chloride fine material storage bin 5 to wait for dechlorination treatment.

Claims

1. A high-temperature and high-pressure steam extraction and dechlorination system for high-chlorine waste, characterized in that: The invention comprises a high-chlorine waste pretreatment unit, a high-chlorine waste transmission-extraction unit and a low-chlorine waste collection unit. The high-chlorine waste transmission-extraction unit comprises a first transmission component, a second transmission component, a steam extraction component and an extrusion component. The first transmission component comprises a first transmission filter cloth (18), the second transmission component comprises a second transmission filter cloth (19), the steam extraction component comprises a high-temperature and high-pressure steam injection device, the outlet of the high-chlorine waste pretreatment unit is located above one end of the first transmission filter cloth (18), one end of the second transmission filter cloth (19) is located above the outlet of the high-chlorine waste pretreatment unit close to the material transmission direction of the first transmission filter cloth (18), and after a distance, it is connected to the first transmission filter cloth (19). The second transmission filter cloth (18) contacts and presses the first transmission filter cloth (18), and then separates from the first transmission filter cloth (18) after a distance. At the position where the second transmission filter cloth (19) is pressed against the first transmission filter cloth (18), a plurality of steam nozzles (9) of high-temperature and high-pressure steam injection devices are provided. Before separation, the second transmission filter cloth (19) and the first transmission filter cloth (18) pass through between the extrusion components. The low-chlorine waste collection unit includes a scraper (10) and a low-chlorine waste collection bin (12). After the second transmission filter cloth (19) is separated from the first transmission filter cloth (18), it contacts one scraper (10) respectively. The outlet between the two scrapers (10) is located above the low-chlorine waste collection bin (12); The first transmission assembly further comprises a plurality of first transmission wheels (13), and the second transmission assembly further comprises a plurality of second transmission wheels (7). One end of the first transmission filter cloth (18) is sleeved on a first transmission wheel (13), and one end of the second transmission filter cloth (19) is sleeved on a second transmission wheel (7). The upper side of the position where the first transmission filter cloth (18) and the second transmission filter cloth (19) just contact each other bypasses a second transmission wheel (7) and turns upward. The position where the first transmission filter cloth (18) and the second transmission filter cloth (19) are pressed together alternately bypasses a plurality of first transmission wheels (13) and second transmission wheels (7). After passing through the extrusion assembly, the first transmission filter cloth (18) and the second transmission filter cloth (19) are respectively turned and separated by a first transmission wheel (13) and a second transmission wheel (7), forming a circular rotation; at the position where the first transmission wheel (13) and the second transmission wheel (7) are alternately arranged, the first transmission filter cloth (18) and the second transmission filter cloth (19) are pressed to form a plurality of pairs of vertical parallel sections, the steam nozzle (9) is a bidirectional nozzle, and a steam nozzle (9) is arranged between each pair of vertical parallel sections before the last pair of vertical parallel sections, and the extrusion assembly is arranged on both sides of the last pair of vertical parallel sections; The extrusion assembly comprises two pairs of extrusion plates (11) and an extrusion control unit. The two extrusion plates (11) in each pair of extrusion plates (11) are respectively arranged on both sides of two vertical parallel sections of the last pair of vertical parallel sections at the compression positions of the first transmission filter cloth (18) and the second transmission filter cloth (19). The two pairs of extrusion plates (11) are connected to the extrusion control unit to control the two pairs of extrusion plates to extrude the vertical parallel sections.

2. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 1, characterized in that: After the contact position of the first transmission filter cloth (18) and the second transmission filter cloth (19) is turned, an acute angle is formed between the first transmission filter cloth (18) and the second transmission filter cloth (19) before the turning, and a steam nozzle (9) is also provided between the second transmission filter cloth (19) before and after the turning.

3. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 1, characterized in that: One of the first transmission wheels (13) is a first tensioning wheel (6), and one of the second transmission wheels (7) is a second tensioning wheel (1).

4. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 1, characterized in that: It also includes a backwashing water device, wherein a backwashing water nozzle (2) of the backwashing water device is provided at the position after the first transmission filter cloth (18) and the second transmission filter cloth (19) are separated.

5. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 1, characterized in that: A chlorine-containing liquid collection pool (8) is provided below the first conveying assembly, the second conveying assembly, and the steam extraction assembly, and an outlet of the chlorine-containing liquid collection pool (8) is connected to a chlorine-containing liquid treatment and recovery system.

6. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 5, characterized in that: The chlorine-containing liquid treatment and recovery system comprises a chlorine-containing liquid concentration unit (14), a calcium-aluminum precipitation unit (15), a Freund's salt collection unit (16) and a purified water recovery unit (17); the outlet of the chlorine-containing liquid collection tank (8) is connected to the chlorine-containing liquid concentration unit (14); the high-chloride wastewater outlet of the chlorine-containing liquid concentration unit (14) is connected to the calcium-aluminum precipitation unit (15); one end of the outlet of the calcium-aluminum precipitation unit (15) is connected to the Freund's salt collection unit (16), and the other end is connected to the purified water recovery unit (17); the concentrated reuse water outlet of the chlorine-containing liquid concentration unit (14) is also connected to the purified water recovery unit (17).

7. The high-temperature and high-pressure steam extraction and dechlorination system for high-chloride waste according to claim 1, characterized in that: The high-chloride waste pretreatment unit comprises a high-chloride coarse material storage bin (3), a wet grinding unit (4) and a high-chloride fine material storage bin (5) connected in sequence, and the lower end outlet of the high-chloride fine material storage bin (5) is located above the first conveying filter cloth (18).

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