Coal chemical industry waste salt resource utilization device

Abstract

The utility model discloses a coal chemical industry waste salt resource utilization device, which belongs to the field of waste treatment and comprises a first cracking unit, a second waste salt re-melting unit, a sludge filtering device, a third flocculent precipitation unit and a fourth evaporation separation unit, the first cracking unit comprises a first pre-drying device for pre-drying waste salt to be treated, a second carbonization furnace for carbonizing the waste salt, a second fuel gas supply device, a second purification device and a third high-temperature cracking assembly. In the application, through the first cracking unit, organic matters and other easily-decomposed carnallite in waste salt can be removed through high-temperature combustion, and the purity of NaCl and Na2SO4 is improved. And corresponding impurities are removed based on remelting and flocculation. Then, a fourth evaporation separation unit is used for recycling water resources, the water treatment amount during evaporation crystallization is reduced, and the influence of organic matter on the evaporation crystallization unit is reduced. And finally, according to the phase diagrams of the redissolved salt NaCl and Na2SO4 water-salt systems, respectively carrying out crystallization treatment on the redissolved salt NaCl and Na2SO4 water-salt systems to obtain purified crystallized salt.

Description

Technical Field

[0001] The utility model relates to the field of waste treatment, in particular to the field of waste salt resource utilization, and specifically is a device for resource utilization of coal chemical waste salt. Background Art

[0002] As an inevitable by-product in coal chemical projects, impure salts contain a variety of inorganic salts and a large amount of organic matter. They have a large output, complex composition and are difficult to dispose of. If impure salts cannot be effectively utilized, it will not only harm the environment, but also cause serious waste of resources.

[0003] To this end, people have conducted a lot of research. For example, Chinese patent application CN202310568359.8 discloses a method and device for harmless treatment of coal chemical waste salts, which is used to screen salts of different particle sizes for the next process treatment. Chinese patent application CN201610342138.9 discloses an electrodialysis device for the separation and concentration of coal chemical concentrated brine, which uses an electrodialysis device equipped with a nanofiltration membrane for the separation and concentration of coal chemical concentrated brine, realizes the classification and recovery of salts, reduces the amount of solid waste that needs to be treated as hazardous waste, and achieves the goal of recycling and "zero emission" of coal chemical concentrated brine. Chinese patent application CN201520042183.3 discloses a coal chemical concentrated brine evaporation crystallization salt separation device, which makes full use of the thermal energy of the system to achieve the full recovery and utilization of coal chemical concentrated brine, solves the problem that the salts produced by other evaporation processes can only be treated as hazardous waste, and minimizes the amount of solid waste that needs to be landfilled. Chinese patent application CN202011129498.3 discloses an underground effective space sealing process for high-salt wastewater from coal mines and coal chemical industry, which replaces the original salt separation crystallization process section, eliminates the output of hazardous waste, makes full use of the unique production characteristics of coal mines, and uses underground goafs and other effective spaces for sealing. At the same time, the entire water treatment system is transplanted to the underground of the coal mine to use idle tunnels, reduce the land acquisition for ground construction, realize on-site reuse underground, and reduce the amount of water discharged to the ground. Chinese patent application CN201520532911.9 discloses an improved low-energy coal chemical concentrated salt water separation crystallization combination device, which overcomes the problems of long process flow, unstable treatment system, and high operating energy consumption in existing evaporation crystallization devices.

[0004] How to realize the resource utilization of coal chemical waste salt has always been an urgent problem that needs to be solved. Utility Model Content

[0005] The invention object of the utility model is to provide a device for resource utilization of coal chemical waste salt, so as to realize resource utilization of coal chemical waste salt, reduce the cost of the operation process, and meet the needs of industrial application.

[0006] In order to achieve the above purpose, this application adopts the following technical solutions:

[0007] A device for resource utilization of waste salt from coal chemical industry, comprising a first cracking unit, a second waste salt remelting unit, a sludge filtering device, a third flocculation and sedimentation unit, and a fourth evaporation and separation unit;

[0008] The first cracking unit includes a first pre-drying device for pre-drying the waste salt to be treated, a second carbonization furnace for carbonizing the waste salt, a second gas supply device, a second purification device, and a third high-temperature cracking assembly;

[0009] The first pre-drying device is connected to the second carbonization furnace and the second carbonization furnace can carbonize the waste salt treated by the first pre-drying device, the second gas supply device is connected to the second carbonization furnace and the second gas supply device can provide gas to the second carbonization furnace as a fuel source for the second gas supply device, the second carbonization furnace is connected to the second purification device and the second purification device can purify the flue gas generated by the second carbonization furnace; the second carbonization furnace is connected to the third high-temperature cracking assembly and the waste salt treated in the second carbonization furnace can be sent to the third high-temperature cracking assembly for high-temperature cracking;

[0010] The second waste salt remelting unit comprises a cooling tower and a remelting pool connected to the third high temperature cracking component, wherein the cooling tower is connected to the third high temperature cracking component and the material processed by the third high temperature cracking component can be sent to the cooling tower for cooling, and the cooling tower is connected to the remelting pool and the material in the cooling tower can be sent to the remelting pool for mixing and dissolving with the recycled water;

[0011] The remelting tank is connected to the sludge filtering device, and the material in the remelting tank can be sent to the sludge filtering device for filtering and processing to obtain a second filtrate and a second sludge respectively;

[0012] The third flocculation sedimentation unit comprises a buffer tank, a flocculating agent adding device, and a third filtering device. The sludge filtering device is connected to the buffer tank and the second filtrate in the sludge filtering device can be sent to the buffer tank. The flocculating agent adding device is connected to the buffer tank and the flocculating agent adding device can add flocculating agent to the buffer tank to cause flocculation reaction in the buffer tank. The buffer tank is connected to the third filtering device and the material in the buffer tank can be sent to the third filtering device for filtering treatment to obtain a third filtered concentrate and a third filtered clear water.

[0013] The fourth evaporation separation unit comprises a fourth evaporation concentration device, a fourth return water temporary storage device, a sodium chloride crystallization device, a sodium sulfate crystallization device, a centrifuge 1, and a centrifuge 2; the third filtering device is connected to the fourth evaporation concentration device, and the third filtered concentrated liquid in the third filtering device can be sent to the fourth evaporation concentration device for evaporation concentration treatment to obtain a fourth evaporation concentrated liquid and a fourth evaporation return water respectively; the fourth evaporation concentration device is connected to the fourth return water temporary storage device, and the fourth evaporation return water generated by the fourth evaporation concentration device can be sent to the fourth return water temporary storage device for temporary storage; the fourth return water temporary storage device is connected to the remelting tank, and the fourth evaporation return water in the fourth return water temporary storage device can be sent to the remelting tank for reuse;

[0014] The fourth evaporation and concentration device is respectively connected to the sodium chloride crystallization device and the sodium sulfate crystallization device, and the fourth evaporation concentrated liquid produced by the fourth evaporation and concentration device can be sent to the sodium chloride crystallization device and the sodium sulfate crystallization device for crystallization;

[0015] The sodium chloride crystallization device is connected to the centrifuge one, and the salt produced by the sodium chloride crystallization device can be sent to the centrifuge one for centrifugal treatment to obtain a crude sodium chloride extract. The sodium sulfate crystallization device is connected to the centrifuge two, and the salt produced by the sodium sulfate crystallization device can be sent to the centrifuge two for centrifugal treatment to obtain a crude sodium sulfate extract.

[0016] The sludge filtering device is a plate-type filtering tank or a tubular filtering tank.

[0017] The third filtering device is an RO filtering device.

[0018] The fourth evaporation and concentration device is an MVR evaporation and concentration device.

[0019] It also includes a sludge collecting device, the remelting tank is connected to the sludge collecting device, and the second sludge in the remelting tank can be sent to the sludge collecting device.

[0020] The invention also comprises a fifth packaging unit, which comprises a drying device 1 for drying sodium chloride, a packaging machine 1, a drying device 2 for drying sodium sulfate, and a packaging machine 2, wherein the centrifuge 1 is connected to the drying device 1 and the crude sodium chloride extract obtained by the centrifuge 1 can be sent to the drying device 1 for drying treatment, and the packaging machine 1 is connected to the drying device 1 and the sodium chloride dried by the drying device 1 can be packaged by the packaging machine 1 to obtain a sodium chloride product;

[0021] The second centrifuge is connected to the second drying device, and the crude sodium sulfate extract obtained by the second centrifuge can be sent to the second drying device for drying. The second packaging machine is connected to the second drying device, and the sodium sulfate dried by the second drying device can be packaged by the second packaging machine to obtain a sodium sulfate product.

[0022] The third high temperature cracking assembly includes a third bracket, a third sleeve, a third rotating drum, a third rotating device, a third combustion device, a third flue gas duct, and a control system;

[0023] The third sleeve is connected to the third bracket and the third sleeve is fixedly connected to the third bracket, the third rotating drum is arranged in the third sleeve and the third rotating drum can rotate relative to the third rotating drum, and the third rotating device is connected to the third rotating drum and the third rotating device can drive the third rotating drum to rotate;

[0024] The third combustion device is connected to the third flue gas duct and the flue gas generated by the third combustion device can enter the third flue gas duct;

[0025] The third sleeve is respectively provided with a waste salt inlet, a waste salt outlet, a flue gas inlet, and a flue gas outlet. The waste salt inlet is connected to the second carbonization furnace, and the waste salt treated in the second carbonization furnace can be sent to the third rotating drum through the waste salt inlet for high-temperature cracking. The horizontal plane where the waste salt outlet is located is located above the horizontal plane where the waste salt inlet is located, and the material treated in the third rotating drum can be sent out through the waste salt outlet;

[0026] The third flue gas duct is connected to the flue gas inlet, and the flue gas generated by the third combustion device can enter the third drum through the third flue gas duct and the flue gas inlet in sequence, and the flue gas outlet is located near the waste salt inlet, and the flue gas contacts the waste salt in the third drum in reverse direction and can be discharged through the flue gas outlet after high-temperature cracking of the waste salt;

[0027] The third rotating device is connected to the control system.

[0028] The third high-temperature cracking component also includes a third gas supply device, which is connected to the third combustion device and can provide gas to the third combustion device as a fuel source for the third combustion device.

[0029] The second gas supply device and the third gas supply device are natural gas supply devices respectively.

[0030] The second carbonization furnace is made of heat-resistant steel.

[0031] The second carbonization furnace is made of 310S stainless steel.

[0032] The third rotating drum is coaxially arranged with the third sleeve.

[0033] The axial direction of the third rotating drum is inclined relative to the horizontal direction.

[0034] The third sleeve and the third flue gas duct are respectively made of heat-insulating materials.

[0035] The waste salt resource utilization device based on high-temperature carbonization and fractional crystallization process can fundamentally solve the problem of waste salt treatment, and it is an inevitable trend for waste salt resource utilization. In this application, through the first cracking unit, the waste salt can be burned at high temperature to remove organic matter and other easily decomposable salts, thereby improving the purity of NaCl and Na2SO4. Based on remelting and flocculation, the corresponding impurities are removed. Next, the fourth evaporation and separation unit is used to recycle water resources, reduce the amount of water to be processed during evaporation and crystallization, and reduce the impact of organic matter on the evaporation and crystallization unit. Finally, according to the phase diagram of the redissolved salt NaCl and Na2SO4 water-salt system, the two are crystallized separately to obtain purified crystalline salt. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the overall structure of the device in Example 1.

[0037] Markings in the figure: 1. the first pre-drying device, 2. the second carbonization furnace, 3. the second gas supply device, 4. the second purification device, 5. the third high-temperature cracking component, 6. the cooling tower, 7. the remelting tank, 8. the sludge filtering device, 9. the buffer tank, 10. the flocculant adding device, 11. the third filtering device, 12. the fourth evaporation concentration device, 13. the fourth return water temporary storage device, 14. the sodium chloride crystallization device, 15. the sodium sulfate crystallization device, 16. the centrifuge one, 17. the centrifuge two, 18. the drying device one, 19. the packaging machine one, 20. the drying device two, 21. the packaging machine two. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0039] The present embodiment provides a device for resource utilization of coal chemical waste salt, which includes a first cracking unit, a second waste salt remelting unit, a sludge filtering device, a third flocculation and sedimentation unit, and a fourth evaporation and separation unit.

[0040] The first cracking unit includes a first pre-drying device for pre-drying the waste salt to be treated, a second carbonization furnace for carbonizing the waste salt, a second gas supply device, a second purification device, and a third high-temperature cracking assembly. The first pre-drying device is used to pre-dry the waste salt to be treated; the first pre-drying device is connected to the second carbonization furnace; the second gas supply device is connected to the second carbonization furnace, and the second gas supply device can provide gas to the second carbonization furnace as a fuel source for the second gas supply device; the second carbonization furnace can carbonize the waste salt treated by the first pre-drying device; the second purification device is connected to the second carbonization furnace, and the second purification device can purify the flue gas generated by the second carbonization furnace; the second carbonization furnace is connected to the third high-temperature cracking assembly. In this embodiment, the second carbonization furnace is made of 310S stainless steel, and the second gas supply device is a natural gas supply device.

[0041] The waste salt treatment process is as follows: the waste salt to be treated is first sent to the first pre-drying device for low-temperature drying pretreatment; then, the waste salt enters the second carbonization furnace for combustion treatment; the second gas supply device provides fuel for the combustion of the second carbonization furnace, and the second purification device treats the flue gas generated by the combustion of the second carbonization furnace; finally, the waste salt enters the third high-temperature cracking component for high-temperature pyrolysis.

[0042] In this embodiment, the third high temperature cracking assembly includes a third bracket, a third sleeve, a third drum, a third rotating device, a third combustion device, a third flue gas pipe, and a control system, and the third rotating device is connected to the control system. Among them, the third sleeve is connected to the third bracket, and the third drum is arranged in the third sleeve; the third rotating device is connected to the third drum, and the third rotating device can drive the third drum to rotate; the third combustion device is connected to the third flue gas pipe, and the flue gas generated by the third combustion device can enter the third flue gas pipe. At the same time, the third sleeve is respectively provided with a waste salt inlet, a waste salt outlet, a flue gas inlet, and a flue gas outlet. The waste salt inlet is connected to the second carbonization furnace; the horizontal plane where the waste salt outlet is located is located above the horizontal plane where the waste salt inlet is located, and the processed materials in the third drum can be sent out through the waste salt outlet; the third flue gas pipe is connected to the flue gas inlet, and the flue gas generated by the third combustion device can enter the third drum through the third flue gas pipe and the flue gas inlet in turn; the flue gas outlet is located near the waste salt inlet, and the flue gas contacts the waste salt in the third drum in reverse direction and can be discharged through the flue gas outlet after high temperature cracking of the waste salt.

[0043] Furthermore, the third high-temperature cracking assembly also includes a third gas supply device, which is connected to the third combustion device, and the third gas supply device can provide gas to the third combustion device as a fuel source for the third combustion device. Preferably, the third drum and the third sleeve are coaxially arranged, and the axial direction of the third drum is inclined relative to the horizontal direction. Furthermore, the third gas supply device uses a natural gas supply device, and the third sleeve and the third flue gas duct are respectively made of heat-insulating materials.

[0044] With this structure, the waste salt treated by the second carbonization furnace enters the third drum through the waste salt inlet, undergoes high-temperature cracking in the third drum, and is finally discharged from the waste salt outlet; during this process, the flue gas generated by the third combustion device enters the third drum through the third flue gas duct and the flue gas inlet in turn, and is discharged through the flue gas outlet after heat exchange with the waste salt in the third drum. The axial direction of the third drum is tilted relative to the horizontal direction; with this structure, the waste moves upward from bottom to top; and the flue gas enters the third drum from the upper flue gas inlet, and is finally discharged from the lower flue gas outlet.

[0045] In this application, the barrel of the second carbonization furnace is preferably made of 310S heat-resistant steel, and the part in contact with the material is a metal part, which has fast heat transfer and will not pollute the material. In this application, the waste salt is treated by the device, and organic matter and other easily decomposable salts are effectively decomposed, realizing the effective recovery of inorganic salts.

[0046] The second waste salt remelting unit includes a cooling tower and a remelting tank connected to the third high-temperature cracking component; the cooling tower is connected to the third high-temperature cracking component, and the material processed by the third high-temperature cracking component can be sent to the cooling tower for cooling; the cooling tower is connected to the remelting tank, and the material in the cooling tower can be sent to the remelting tank to mix and dissolve with recycled water. At the same time, the remelting tank is connected to the sludge filtering device, and the material in the remelting tank can be sent to the sludge filtering device for filtering and treatment, and the second filtrate and the second sludge are obtained respectively. Preferably, a sludge collecting device is also included. The remelting tank is connected to the sludge collecting device, and the second sludge in the remelting tank can be sent to the sludge collecting device.

[0047] In this embodiment, the third flocculation sedimentation unit includes a buffer tank, a flocculation agent adding device, and a third filter device. Among them, the sludge filter device is connected to the buffer tank, and the second filtrate in the sludge filter device can be sent to the buffer tank; the flocculation agent adding device is connected to the buffer tank, and the flocculation agent adding device can add flocculants to the buffer tank to cause flocculation reaction in the buffer tank; the buffer tank is connected to the third filter device, and the material in the buffer tank can be sent to the third filter device for filtration treatment, and the third filtration concentrate and the third filtration water are obtained. Preferably, the third filter device is an RO filter device.

[0048] The fourth evaporation separation unit includes a fourth evaporation concentration device, a fourth return water temporary storage device, a sodium chloride crystallization device, a sodium sulfate crystallization device, a centrifuge 1, and a centrifuge 2. Among them, the third filter device is connected to the fourth evaporation concentration device, and the third filtered concentrated liquid in the third filter device can be sent to the fourth evaporation concentration device for evaporation concentration treatment, and the fourth evaporation concentrate and the fourth evaporation return water are obtained respectively. The fourth evaporation concentration device is connected to the fourth return water temporary storage device, and the fourth evaporation return water generated by the fourth evaporation concentration device can be sent to the fourth return water temporary storage device for temporary storage. The fourth return water temporary storage device is connected to the remelting tank, and the fourth evaporation return water in the fourth return water temporary storage device can be sent to the remelting tank for reuse.

[0049] At the same time, the fourth evaporation and concentration device is connected to the sodium chloride crystallization device and the sodium sulfate crystallization device respectively, and the fourth evaporation and concentration liquid produced by the fourth evaporation and concentration device can be sent to the sodium chloride crystallization device and the sodium sulfate crystallization device for crystallization. The sodium chloride crystallization device is connected to centrifuge one, and the salt produced by the sodium chloride crystallization device can be sent to centrifuge one for centrifugal treatment, and a crude sodium chloride extract is obtained. The sodium sulfate crystallization device is connected to centrifuge two, and the salt produced by the sodium sulfate crystallization device can be sent to centrifuge two for centrifugal treatment, and a crude sodium sulfate extract is obtained. Preferably, a fifth packaging unit is also included, and the fifth packaging unit includes a drying device one for drying sodium chloride, a packaging machine one, a drying device two for drying sodium sulfate, and a packaging machine two. Among them, centrifuge one is connected to drying device one, and the crude sodium chloride extract obtained by centrifuge one can be sent to drying device one for drying treatment, packaging machine one is connected to drying device one, and the sodium chloride dried by drying device one can be packaged by packaging machine one, and a sodium chloride product is obtained. The second centrifuge is connected to the second drying device, and the crude sodium sulfate extract obtained by the second centrifuge can be sent to the second drying device for drying; the second packaging machine is connected to the second drying device, and the sodium sulfate dried by the second drying device can be packaged by the second packaging machine to obtain a sodium sulfate product. Further, the fourth evaporation concentration device is an MVR evaporation concentration device.

[0050] In this application, the waste salt is first processed by the first cracking unit, in which the second carbonization furnace uses natural gas, biogas, coal gas, etc. as heat sources for high-temperature calcination. The temperature of the material in the second carbonization furnace is controlled between 550 and 750°C, and the material stays in the furnace for more than 120 minutes to ensure that the organic matter is completely decomposed. Considering that the temperature of the contact part between the barrel of the second carbonization furnace and the heat source will reach 800°C, it is recommended to select heat-resistant steel such as 310S for the material of the barrel. At the same time, after being treated in the second carbonization furnace, high-temperature cracking is carried out through the third high-temperature cracking component.

[0051] After the first cracking unit is completed, the waste salt is re-dissolved: after the waste salt passes through the third high-temperature cracking component to remove the corresponding organic matter, it is merged with the fourth evaporation return water of evaporation and condensation; because the waste salt is cracked and then re-melted, there will be some insoluble matter, such as mud, calcium sulfate, etc., which can be effectively removed through re-melting and subsequent filtration treatment.

[0052] After filtering, the material is sent to the third flocculation and precipitation unit, where it is treated with a flocculant to obtain a third filtration concentrate and a third filtration clear water. The redissolved brine is usually strongly alkaline, and the pH is adjusted to a weakly alkaline pH of about 9 by adding hydrochloric acid to create the best reaction conditions for subsequent calcium and magnesium removal.

[0053] The removal of calcium and magnesium ions is mainly achieved by adding precipitating agent Na2CO3 to react with magnesium ions and calcium ions in the remelted brine to form water-insoluble precipitates. The precipitation mechanism of Na2CO3 on magnesium and calcium ions in the water wash liquid is described in the following reaction formula.

[0054] Na2CO3+Ca 2+ =CaCO3↓+2Na +

[0055] Na2CO3+Mg 2+ =MgCO3↓+2Na +

[0056] At the same time, sodium carbonate can also react with some heavy metals such as Pb, Zn, etc. in the remelted brine to form carbonate precipitates. The reaction formula is as follows.

[0057] Na2CO3+Pb 2+ =PbCO3↓+2Na +

[0058] Na2CO3+Zn 2+ =ZnCO3↓+2Na +

[0059] During the precipitation process, heavy metal carbonate precipitates such as CaCO3 and MgCO3 will undergo co-precipitation to adsorb some heavy metal ions, further improving the removal effect of heavy metal ions.

[0060] Finally, the third filtered concentrate is sent to the fourth evaporation separation unit for treatment. In the present application, slight negative pressure evaporation is adopted, the evaporation temperature is 90°C, and the boiling point of the solution rises by nearly 15°C.

[0061] Example 1

[0062] The above-mentioned device was used to treat waste salt produced by a coal chemical enterprise. The waste salt contained the following components (in percentage by mass): sodium chloride 75.64%, sodium sulfate 20.47%, water 2.46%, total organic carbon (TOC) 1.08%, and other impurities 0.35%.

[0063] The product after treatment by the device was measured, and the generated product included two salts, sodium chloride and sodium sulfate, and its components were (by mass percentage):

[0064] (1) Sodium chloride salt: sodium chloride content 98.6%, total organic carbon (TOC) content 35 mg / kg, sodium sulfate 0.7%, water 0.6%;

[0065] (2) Sodium sulfate salt: sodium sulfate content 97.2%, total organic carbon (TOC) content 46 mg / kg, sodium chloride content 0.9%, water content 0.9%, other impurities 1.0%.

[0066] Example 2

[0067] The above-mentioned device was used to treat the waste salt produced by a coal-to-methanol enterprise. The waste salt contained the following components (in percentage by mass): sodium chloride 81.48%, sodium sulfate 13.68%, water 3.46%, total organic carbon (TOC) 0.86%, and other impurities 0.52%.

[0068] The product after treatment by the device was measured, and the generated product included two salts, sodium chloride and sodium sulfate, and its components were (by mass percentage):

[0069] (1) Sodium chloride salt: sodium chloride content 98.9%, total organic carbon (TOC) content 32 mg / kg, sodium sulfate 0.6%, water 0.5%;

[0070] (2) Sodium sulfate salt: sodium sulfate content 96.7%, total organic carbon (TOC) content 41 mg / kg, sodium chloride content 1.5%, water 1.2%, other impurities 0.6%.

[0071] Example 3

[0072] The above-mentioned device was used to treat the waste salt produced by the mine water treatment of a coal mine. The waste salt contained the following components (in percentage by mass): sodium chloride 63.81%, sodium sulfate 32.25%, water 1.75%, total organic carbon (TOC) 0.54%, and other impurities 1.65%.

[0073] The product after treatment by the device was measured, and the generated product included two salts, sodium chloride and sodium sulfate, and its components were (by mass percentage):

[0074] (1) Sodium chloride salt: sodium chloride content 96.4%, total organic carbon (TOC) content 47 mg / kg, sodium sulfate 1.2%, water 0.9%, other impurities 1.5%.

[0075] (2) Sodium sulfate salt: sodium sulfate content 97.8%, total organic carbon (TOC) content 39 mg / kg, sodium chloride content 0.8%, water content 0.5%, other impurities 0.9%.

[0076] 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 and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for resource utilization of coal chemical waste salt, characterized in that: It includes a first cracking unit, a second waste salt remelting unit, a sludge filtering device, a third flocculation and sedimentation unit, and a fourth evaporation and separation unit; The first cracking unit includes a first pre-drying device for pre-drying the waste salt to be treated, a second carbonization furnace for carbonizing the waste salt, a second gas supply device, a second purification device, and a third high-temperature cracking assembly; The first pre-drying device is connected to the second carbonization furnace and the second carbonization furnace can carbonize the waste salt treated by the first pre-drying device, the second gas supply device is connected to the second carbonization furnace and the second gas supply device can provide gas to the second carbonization furnace as a fuel source for the second gas supply device, the second carbonization furnace is connected to the second purification device and the second purification device can purify the flue gas generated by the second carbonization furnace; the second carbonization furnace is connected to the third high-temperature cracking assembly and the waste salt treated in the second carbonization furnace can be sent to the third high-temperature cracking assembly for high-temperature cracking; The second waste salt remelting unit comprises a cooling tower and a remelting pool connected to the third high temperature cracking component, wherein the cooling tower is connected to the third high temperature cracking component and the material processed by the third high temperature cracking component can be sent to the cooling tower for cooling, and the cooling tower is connected to the remelting pool and the material in the cooling tower can be sent to the remelting pool for mixing and dissolving with the recycled water; The remelting tank is connected to the sludge filtering device, and the material in the remelting tank can be sent to the sludge filtering device for filtering and processing to obtain a second filtrate and a second sludge respectively; The third flocculation sedimentation unit comprises a buffer tank, a flocculating agent adding device, and a third filtering device. The sludge filtering device is connected to the buffer tank and the second filtrate in the sludge filtering device can be sent to the buffer tank. The flocculating agent adding device is connected to the buffer tank and the flocculating agent adding device can add flocculating agent to the buffer tank to cause flocculation reaction in the buffer tank. The buffer tank is connected to the third filtering device and the material in the buffer tank can be sent to the third filtering device for filtering treatment to obtain a third filtered concentrate and a third filtered clear water. The fourth evaporation separation unit comprises a fourth evaporation concentration device, a fourth return water temporary storage device, a sodium chloride crystallization device, a sodium sulfate crystallization device, a centrifuge 1, and a centrifuge 2; the third filtering device is connected to the fourth evaporation concentration device, and the third filtered concentrated liquid in the third filtering device can be sent to the fourth evaporation concentration device for evaporation concentration treatment to obtain a fourth evaporation concentrated liquid and a fourth evaporation return water respectively; the fourth evaporation concentration device is connected to the fourth return water temporary storage device, and the fourth evaporation return water generated by the fourth evaporation concentration device can be sent to the fourth return water temporary storage device for temporary storage; the fourth return water temporary storage device is connected to the remelting tank, and the fourth evaporation return water in the fourth return water temporary storage device can be sent to the remelting tank for reuse; The fourth evaporation and concentration device is respectively connected to the sodium chloride crystallization device and the sodium sulfate crystallization device, and the fourth evaporation concentrated liquid produced by the fourth evaporation and concentration device can be sent to the sodium chloride crystallization device and the sodium sulfate crystallization device for crystallization; The sodium chloride crystallization device is connected to the centrifuge one, and the salt produced by the sodium chloride crystallization device can be sent to the centrifuge one for centrifugal treatment to obtain a crude sodium chloride extract. The sodium sulfate crystallization device is connected to the centrifuge two, and the salt produced by the sodium sulfate crystallization device can be sent to the centrifuge two for centrifugal treatment to obtain a crude sodium sulfate extract.

2. The device according to claim 1, characterized in that The sludge filtering device is a plate-type filtering tank or a tubular filtering tank.

3. The device according to claim 1, characterized in that The third filtering device is an RO filtering device.

4. The device according to claim 1, characterized in that The fourth evaporation and concentration device is an MVR evaporation and concentration device.

5. The device according to claim 1, characterized in that It also includes a sludge collecting device, the remelting tank is connected to the sludge collecting device, and the second sludge in the remelting tank can be sent to the sludge collecting device.

6. The device according to any one of claims 1 to 5, characterized in that: The invention also comprises a fifth packaging unit, which comprises a drying device 1 for drying sodium chloride, a packaging machine 1, a drying device 2 for drying sodium sulfate, and a packaging machine 2, wherein the centrifuge 1 is connected to the drying device 1 and the crude sodium chloride extract obtained by the centrifuge 1 can be sent to the drying device 1 for drying treatment, and the packaging machine 1 is connected to the drying device 1 and the sodium chloride dried by the drying device 1 can be packaged by the packaging machine 1 to obtain a sodium chloride product; The second centrifuge is connected to the second drying device, and the crude sodium sulfate extract obtained by the second centrifuge can be sent to the second drying device for drying. The second packaging machine is connected to the second drying device, and the sodium sulfate dried by the second drying device can be packaged by the second packaging machine to obtain a sodium sulfate product.

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