CN109956485B - Device and method for removing organic matter impurities in byproduct sodium chloride salt - Google Patents
Device and method for removing organic matter impurities in byproduct sodium chloride salt Download PDFInfo
- Publication number
- CN109956485B CN109956485B CN201910240118.4A CN201910240118A CN109956485B CN 109956485 B CN109956485 B CN 109956485B CN 201910240118 A CN201910240118 A CN 201910240118A CN 109956485 B CN109956485 B CN 109956485B
- Authority
- CN
- China
- Prior art keywords
- sodium chloride
- liquid
- inlet
- outlet
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D3/00—Halides of sodium, potassium or alkali metals in general
- C01D3/14—Purification
Abstract
The invention belongs to the technical field of chemical process and equipment, and relates to a purification and recovery device and a purification and recovery method for byproduct sodium chloride in a chlorination chemical process. Firstly, carrying out high-temperature oxidation on most organic impurities in the sodium chloride salt as a secondary product by a multilayer fluidized bed type high-temperature oxidation reactor, then carrying out deep oxidation on residual trace organic impurities in a liquid-phase deep oxidation tower, and further removing macromolecular organic impurities in the sodium chloride salt by a nanofiltration membrane separator so as to meet the requirements of an ionic membrane caustic soda industrial device on the organic impurities in the sodium chloride raw material. The device and the method provided by the invention have the characteristics of high operation flexibility, high organic matter impurity treatment efficiency and the like.
Description
Technical Field
The invention belongs to the technical field of chemical process and equipment, and relates to a device and a method for removing organic impurities in a byproduct sodium chloride salt.
Background
Sodium chloride containing organic impurities can be byproduct in the organic chloride chemical production process, the output of the byproduct sodium chloride is more and more large along with the development of the organic chloride chemical industry, the byproduct sodium chloride is already qualified as dangerous waste along with the continuous emergence of new national regulations, the supervision on the byproduct sodium chloride is stricter, and the byproduct sodium chloride is not recycled, so that the resource waste is caused, and the comprehensive utilization of the byproduct sodium chloride is imperative. The method is characterized in that the purified by-product sodium chloride salt is returned to the salt chemical production process as a raw material to realize the cyclic utilization of chlorine element, is a necessary way for harmless treatment of the sodium chloride salt, and is a fundamental way for large-scale sodium chloride salt digestion if the purified by-product sodium chloride salt is used as the raw material of the ionic membrane caustic soda preparation device to meet the quality requirement of the sodium chloride for the ionic membrane caustic soda. For sodium chloride salt which is a byproduct in the organic chloride chemical process, the main impurities are residual organic impurities, and sodium chloride for ion membrane caustic soda requires that the organic impurities in the sodium chloride do not exceed 20mg/kgNaCl in terms of total carbon content.
At present, the literature reports that the methods for treating sodium chloride salt containing organic impurities mainly comprise the following methods: firstly, the salt washing method is used for removing impurities or other components in organic waste salt by using water and a detergent, but the method is only suitable for treating single waste salt with low impurity content; the second is a high-temperature treatment method, which decomposes organic impurities in salt into gas at high temperature and then treats the gas so as to achieve the purpose of removing the organic impurities, but the problems of nozzle blockage, abrasion, high-temperature adhesion, caking, equipment corrosion and the like are easy to occur in the high-temperature treatment; and thirdly, a high-temperature carbonization method, in which organic waste salt is carbonized and decomposed at a high temperature, so that organic impurities in the waste salt are partially decomposed into volatile gas and partially coked into organic carbon, but the problems that the carbonization temperature and the surface softening of the salt are difficult to control, the adhesion to carbonization equipment is easily formed, the continuous production is influenced and the like exist. In addition to the engineering problems of the above methods, the final total carbon content in the treated sodium chloride hardly meets the quality requirements of the ionic membrane caustic soda on the sodium chloride raw material.
Disclosure of Invention
The invention provides a device and a method for removing organic impurities in a byproduct sodium chloride salt, aiming at solving the problems in the prior art, and the device and the method can improve the heat efficiency, meet the quality requirement, and have low cost and the like.
In order to realize the purpose of the invention, the technical scheme is as follows:
a device for removing organic impurities in byproduct sodium chloride salt comprises a high-temperature oxidation reactor, a dissolving kettle A, a dissolving kettle B, a liquid-phase deep oxidation tower, a liquid-solid filter, a solid slag tank and a fine filter which are connected in sequence;
the high-temperature oxidation reactor is a plurality of layers of fluidized beds, each layer is provided with a sieve plate, and each sieve plate is provided with a powder overflow downcomer; 4-16 burners are arranged on the wall of the middle lower part of the high-temperature oxidation reactor, a flue gas discharge pipe is arranged at the top of the high-temperature oxidation reactor, an air inlet and a tilted plate type gas distribution plate at the corresponding position in the fluidized bed are arranged on the side surface of the lower part of the high-temperature oxidation reactor, a salt powder inlet is arranged on the side surface of the upper part of the high-temperature oxidation reactor, and a salt powder outlet is arranged on the side surface of the lower part of the high-temperature oxidation reactor; each combustor is respectively provided with an air inlet pipe and a gas inlet pipe; the salt powder outlet is connected with a bucket type lifting feed inlet at the bottom of the bucket type lifter through a pipeline;
the dissolving kettle A is a stirring kettle, the top of the dissolving kettle A is provided with a powder inlet A and a water inlet A, and the bottom of the dissolving kettle A is provided with a salt solution outlet A; the dissolving kettle B is a stirring kettle, the top of the dissolving kettle B is provided with a powder inlet B and a water inlet B, and the bottom of the dissolving kettle B is provided with a salt solution outlet B; the powder inlet A and the powder inlet B are respectively connected with a bucket type lifting discharge hole at the top of a bucket type lifter; the saline solution outlet A and the saline solution outlet B are respectively connected with the inlet of the centrifugal pump A through valves; the outlet of the centrifugal pump A is connected with the inlet of the flow regulating controller A;
the liquid phase deep oxidation tower is a tower reactor, and the gas-liquid contact mode is a multi-layer bubbling gas-liquid contact mode or a filler gas-liquid contact mode; the side surface of the upper part of the liquid-phase deep oxidation tower is provided with a salt solution inlet, the side surface of the lower part of the liquid-phase deep oxidation tower is provided with a gas inlet, the bottom of the liquid-phase deep oxidation tower is provided with a sodium chloride solution outlet, and the top of the liquid-phase deep oxidation tower is provided with a gas outlet; the salt solution inlet is connected with the outlets of the flow regulating controller A and the flow regulating controller B; a discharge port at the lower part of the oxidant storage tank is connected with an inlet of a flow regulating controller B through a centrifugal pump B; the sodium chloride solution outlet is connected with the inlet of the pressure pump A; the outlet of the pressure pump A is connected with the inlet of the flow regulating controller C;
a downcomer is arranged in the liquid phase deep oxidation tower and is cylindrical or sector cylindrical;
the liquid-solid filter is a plate-and-frame filter press, a filter pressing feed inlet of the liquid-solid filter is connected with an outlet of the flow regulating controller C, and a filtrate outlet of the liquid-solid filter is connected with an inlet of the pressure pump B; the outlet of the pressure pump B is connected with the inlet of the flow regulating controller D;
the fine filter is a nanofiltration membrane filter, the inlet of the fine filter is connected with the outlet of the flow regulating controller D, the filtrate outlet is connected with the inlet of the delivery pump, and the filtered residual liquid outlet is connected with the top water inlet A of the dissolving kettle A and the top water inlet B of the dissolving kettle B; the outlet of the delivery pump is connected with a subsequent ionic membrane caustic soda industrial device;
the outlet of the flow regulating controller A is directly connected with a filter pressing feed inlet of the liquid-solid filter through a valve; the outlet of the flow regulating controller D can be directly connected with a subsequent ionic membrane caustic soda industrial device through a valve.
Preferably, the number of layers of the sieve plate in the high-temperature oxidation reactor is 10-20, and the interlayer spacing is 0.4-0.6 m; the powder overflow downcomer is 0.1-0.4 m higher than the sieve plate; the burners are arranged on the 5 th layer to the 8 th layer from bottom to top of the high-temperature oxidation reactor, and 1 to 4 burners are circumferentially arranged on the wall of each layer of the reactor.
Preferably, when the liquid phase deep oxidation tower is in a multi-layer bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 10-20, the layer spacing is 0.6-1.0 m, and the downcomer is 0.1-0.6 m higher than a tower plate; when the liquid phase deep oxidation tower is in a packing gas-liquid contact mode, the packing is a stepped ring or plate corrugated regular packing made of polypropylene plastics, and the height of the packing is 8-15 m.
Preferably, the average pore diameter of the nanofiltration membrane of the fine filter is 1.2 nm-1.8 nm.
Preferably, the number of layers of the sieve plate in the high-temperature oxidation reactor is 15, and the interlayer spacing is 0.5 m; the powder overflow downcomer is 0.25m higher than the sieve plate; burners are arranged on the walls of the 5 th layer to the 8 th layer of the high-temperature oxidation reactor from bottom to top, and each layer is provided with 3-4 burners;
when the liquid phase deep oxidation tower is in a multi-layer bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 16, the layer spacing is 0.8m, and the height of a downcomer is 0.4m higher than that of a tower plate; when the liquid phase deep oxidation tower is in a packing gas-liquid contact mode, the packing is a stepped ring or plate corrugated regular packing made of polypropylene plastics, and the height of the packing is 13 m;
the average pore diameter of the nanofiltration membrane of the fine filter is 1.5 nm.
A method for removing organic impurities in by-product sodium chloride salt by using the device comprises the following steps:
a. opening valves on an air inlet pipe and a natural gas inlet pipe on a combustor, igniting the combustor simultaneously, starting to add salt powder with the TOC content of less than 3000mg/kg NaCl to the top of the high-temperature oxidation reactor through a salt powder inlet when the highest temperature in the high-temperature oxidation reactor, namely the hot spot temperature reaches 300 ℃, simultaneously opening the valve on the air inlet and adjusting the air flow rate to enable the salt powder on the tower plate to be in a fluidized state, and enabling the salt powder to flow from top to bottom among all layers of sieve plates in the high-temperature oxidation reactor through a powder overflow downcomer; raising the hot spot temperature of the high-temperature oxidation reactor to an operating temperature by adjusting the air flow and the natural gas flow entering each combustor; the temperature of the hot spot is positioned in the middle of the high-temperature oxidation reactor; adjusting the feeding amount of the salt powder inlet to ensure that the high-temperature oxidation reactor achieves stable operation, wherein the retention time of the salt powder in the high-temperature oxidation reactor is 10-30 min; high-temperature combustion gas sprayed by a burner is mixed with air coming from an air inlet to form high-temperature gas which is in fluidized contact with sodium chloride on a sieve plate, so that most of organic impurities in the sodium chloride react with oxygen at high temperature to be oxidized, then the high-temperature gas heats salt powder from top to bottom to reduce the temperature, and then the high-temperature gas is discharged from a flue gas discharge pipe at the top of a high-temperature oxidation reactor;
b. salt powder discharged from a salt powder outlet at the bottom of the high-temperature oxidation reactor enters a bucket elevator from a salt powder hopper type lifting feed inlet, is lifted and conveyed by the bucket elevator, enters a dissolving kettle A from a bucket lifting discharge port through a powder inlet A or enters a dissolving kettle B through a powder inlet B, is added with dissolving water or unfiltered liquid from a filtered residual liquid outlet on a fine filter through a water inlet A or a water inlet B, and is dissolved to prepare a sodium chloride salt solution with the mass concentration of 17-30%; the dissolving kettle A and the dissolving kettle B are alternately used to realize the continuous operation of the subsequent process;
c. sodium chloride salt solution from a salt solution outlet A of the dissolving kettle A or a salt solution outlet B of the dissolving kettle B enters a centrifugal pump A for pressurization; if the TOC value in the sodium chloride salt solution is less than 20mg/kgNaCl according to the sodium chloride, directly entering the step e after passing through a flow regulation controller A;
d. if the TOC value in sodium chloride solution is more than or equal to 20mg/kgNaCl according to sodium chloride, the pressurized sodium chloride solution enters a liquid-phase deep oxidation tower from a salt solution inlet through a flow regulation controller A; the liquid oxidant from the discharge hole of the oxidant storage tank enters the liquid-phase deep oxidation tower from the saline solution inlet through the centrifugal pump B and the flow regulating controller B; air containing a gas-phase oxidant enters the liquid-phase deep oxidation tower from the gas inlet, fully contacts with the sodium chloride salt solution in a multi-layer bubbling mode, promotes the liquid oxidant and the gas-phase oxidant to cooperate with each other to deeply oxidize organic matter impurities in the sodium chloride salt solution, and then is discharged from the gas outlet; the sodium chloride solution flows from top to bottom in the liquid-phase deep oxidation tower through a downcomer; pressurizing the sodium chloride solution from a sodium chloride solution outlet at the bottom of the liquid-phase deep oxidation tower by a pressurizing pump A and adjusting the flow by a flow adjusting controller C;
e. the sodium chloride solution enters a filter pressing feed inlet of a liquid-solid filter, and original solid impurities in the sodium chloride solution and residual carbon and other particulate matters in the combustion process are removed through the filtering action; the filtrate obtained by the liquid-solid filter enters a pressurizing pump B from a discharge hole to be pressurized; if the TOC value in the filtrate is less than 20mg/kgNaCl according to the sodium chloride, directly sending the filtrate to an ionic membrane caustic soda industrial device; the filter cake filtered by the liquid-solid filter enters a solid slag groove;
f. when the TOC value in the filtrate is more than or equal to 20mg/kgNaCl according to sodium chloride, the filtrate pressurized by the pressure pump B enters an inlet of a fine filter, and unoxidized macromolecular organic matter impurities in the sodium chloride salt solution are further removed through nanofiltration membrane filtration to obtain a sodium chloride solution; returning the solution left after filtering to the dissolving kettle A or the dissolving kettle B through a filtering residual solution outlet;
g. and (3) when the TOC value of the sodium chloride solution obtained from the fine filter is less than 20mg/kgNaCl according to the sodium chloride, conveying the sodium chloride solution from a filtrate outlet to an ionic membrane caustic soda industrial device by a conveying pump, and otherwise, returning the sodium chloride solution to the dissolving kettle A or the dissolving kettle B.
Preferably, the operating temperature in the step a is 350-820 ℃, the residence time of the salt powder in the high-temperature oxidation reactor is 15-25 min, the oxygen content of the high-temperature gas is 5.0-16.0%, and the air velocity of the hollow tower in the high-temperature oxidation reactor is 0.3-0.6 m/s; the total carbon content TOC in the salt powder discharged from the salt powder outlet of the high-temperature oxidation reactor is 10 mg/kgNaCl-200 mg/kgNaCl according to the sodium chloride.
Preferably, the sodium chloride solution in the step b has a sodium chloride mass concentration of 20-25%.
Preferably, the liquid oxidant in step d is hydrogen peroxide or sodium hypochlorite, and the mass concentration of the liquid oxidant is 10-30%; the ratio of the mass flow of the sodium chloride solution entering the liquid-phase deep oxidation tower to the mass flow of the liquid oxidant is 100: 1-100: 5, and the liquid-phase solution formed by combining the sodium chloride solution and the liquid oxidant solution stays in the liquid-phase deep oxidation tower for 5-30 min from top to bottom; the air velocity of the air in the liquid phase deep oxidation tower is 0.1-0.4 m/s; the gas-phase oxidant is ozone or chlorine, and the molar content of the gas-phase oxidant in the air is 1.0-5.0%; the reaction temperature in the liquid-phase deep oxidation tower is 15-60 ℃; the TOC value of the sodium chloride salt solution is 10 mg/kgNaCl-60 mg/kgNaCl according to the sodium chloride.
Preferably, the TOC value of the filtrate in the step e is 5 mg/kgNaCl-40 mg/kgNaCl according to sodium chloride, and the TOC value of the sodium chloride solution in the step f is less than 20mg/kgNaCl according to sodium chloride.
Compared with the prior art, the invention has the outstanding effects that:
(1) the high-temperature treatment is carried out on the byproduct sodium chloride salt by adopting a multilayer fluidized bed high-temperature oxidation reactor, the operation temperature of each layer is uniform and controllable, and the problems of nozzle blockage, abrasion, high-temperature adhesion, crusting, equipment corrosion and the like can be solved; the upper part of the multi-layer fluidized bed dries the wet sodium chloride salt powder by high-temperature gas, and the lower part preheats the fluidized air by the high-temperature salt powder to reduce the temperature, so the utilization rate of the heat efficiency is high; the retention time of the salt powder in the multilayer fluidized bed can be regulated and controlled so as to meet the requirements of treating different salt raw materials.
(2) And (3) deeply oxidizing the residual organic impurities in the salt by adopting a liquid-phase deep oxidation tower so as to meet the quality requirement of the ionic membrane caustic soda on the sodium chloride raw material. The liquid phase deep oxidation tower has the advantages of simple operation and low cost.
(3) And a nanofiltration membrane is adopted to finely filter trace unoxidized macromolecular organic matter impurities, carbonized particles and other solid particles in the sodium chloride solution so as to ensure that the content of the solid impurities in the sodium chloride solution meets the requirement.
The invention has wide application and wide market prospect.
Drawings
FIG. 1: schematic structure of the device of the invention
Detailed Description
The invention is further described in detail below with reference to the drawings and the detailed description.
Referring to fig. 1, the parts in the figure are numbered as follows:
1. a high temperature oxidation reactor; 2. a bucket elevator; 3. a dissolving kettle A; 4. a dissolving kettle B; 5. a centrifugal pump A; 6. an oxidant storage tank; 7. a centrifugal pump B; 8. a liquid phase deep oxidation tower; 9. a pressure pump A; 10. a liquid-solid filter; 11. a slag solidification groove; 12. a pressure pump B; 13. a fine filter; 14. a delivery pump; 15. an ionic membrane caustic soda industrial plant; 16. a salt powder inlet; 17. a flue gas discharge pipe; 18. a sieve plate; 19. a powder overflow downcomer; 20. a gas distribution plate; 21. an air inlet; 22. a salt powder outlet; 23. a burner; 24. an air inlet pipe; 25. a gas inlet pipe; 26. a bucket type lifting feed inlet; 27. a bucket type lifting discharge port; 28. a powder inlet A; 29. a water inlet A; 30. a powder inlet B; 31. a water inlet B; 32. a saline solution outlet A; 33. a saline solution outlet B; 34. a flow regulating controller A; 35. a saline solution inlet; 36. a gas discharge port; 37. a downcomer; 38. a gas inlet; 39. a sodium chloride solution outlet; 40. filter pressing the feed inlet; 41. a flow rate regulation controller B; 42. a flow rate regulation controller C; 43. a flow rate regulation controller D; 44. a filtered residual liquid outlet; 45. and (6) a filtrate outlet.
A device for removing organic impurities in byproduct sodium chloride salt comprises a high-temperature oxidation reactor 1, a dissolving kettle A3, a dissolving kettle B4, a liquid-phase deep oxidation tower 8, a liquid-solid filter 10, a solid slag tank 11 and a fine filter 13 which are connected in sequence;
the high-temperature oxidation reactor 1 is a plurality of layers of fluidized beds, each layer is provided with a sieve plate 18, and a powder overflow downcomer 19 is arranged on one sieve plate 18; 4-16 burners 23 are arranged on the wall of the lower middle part of the high-temperature oxidation reactor 1, a flue gas discharge pipe 17 is arranged at the top, an air inlet 21 and an inclined plate type gas distribution plate 20 at the corresponding position in the fluidized bed are arranged on the side surface of the lower part, a salt powder inlet 16 is arranged on the side surface of the upper part, and a salt powder outlet 22 is arranged on the side surface of the lower part; each combustor 23 is respectively provided with an air inlet pipe 24 and a fuel gas inlet pipe 25; the salt powder outlet 22 is connected with a bucket type lifting feed inlet 26 at the bottom of the bucket type lifter 2 through a pipeline;
the dissolving kettle A3 is a stirring kettle, the top of the dissolving kettle is provided with a powder inlet A28 and a water inlet A29, and the bottom of the dissolving kettle is provided with a salt solution outlet A32; the dissolving kettle B4 is a stirring kettle, the top of the dissolving kettle is provided with a powder inlet B30 and a water inlet B31, and the bottom of the dissolving kettle is provided with a salt solution outlet B33; the powder inlet A28 and the powder inlet B30 are respectively connected with a bucket type lifting discharge port 27 at the top of the bucket type lifter 2; the saline solution outlet A32 and the saline solution outlet B33 are respectively connected with the inlet of a centrifugal pump A5 through valves; the outlet of the centrifugal pump A5 is connected with the inlet of a flow regulating controller A34;
the liquid phase deep oxidation tower 8 is a tower reactor, and the gas-liquid contact form is a multilayer bubbling gas-liquid contact form or a filler gas-liquid contact form; the side surface of the upper part of the liquid phase deep oxidation tower 8 is provided with a salt solution inlet 35, the side surface of the lower part is provided with a gas inlet 38, the bottom is provided with a sodium chloride solution outlet 39, and the top is provided with a gas outlet 36; the salt solution inlet 35 is connected with the outlets of a flow regulating controller A34 and a flow regulating controller B41; a discharge hole at the lower part of the oxidant storage tank 6 is connected with an inlet of a flow regulating controller B41 through a centrifugal pump B7; the sodium chloride solution outlet 39 is connected with the inlet of a pressurizing pump A9; the outlet of the pressure pump A9 is connected with the inlet of a flow regulating controller C42;
a downcomer 37 is arranged in the liquid phase deep oxidation tower 8, and the downcomer 37 is cylindrical or sector cylindrical;
the liquid-solid filter 10 is a plate-and-frame filter press, a filter pressing feed inlet 40 of the liquid-solid filter is connected with an outlet of a flow regulating controller C42, and a filtrate outlet of the liquid-solid filter 10 is connected with an inlet of a pressure pump B12; the outlet of the booster pump B12 is connected with the inlet of the flow regulating controller D43;
the fine filter 13 is a nanofiltration membrane filter, the inlet of the fine filter is connected with the outlet of a flow regulating controller D43, the filtrate outlet 45 is connected with the inlet of a delivery pump 14, and the filtered residual liquid outlet 44 is connected with a top water inlet A29 of a dissolving kettle A3 and a top water inlet B31 of a dissolving kettle B4; the outlet of the delivery pump 14 is connected with a subsequent ionic membrane caustic soda industrial device 15;
the outlet of the flow regulating controller A34 is directly connected with the filter pressing feed inlet 40 of the liquid-solid filter 10 through a valve; the outlet of the flow regulating controller D43 can be directly connected with a subsequent ion membrane caustic soda industrial device 15 through a valve.
Preferably, the number of layers of the sieve plate 18 in the high-temperature oxidation reactor 1 is 10-20, and the interlayer spacing is 0.4-0.6 m; the powder overflow downcomer 19 is 180.1-0.4 m higher than the sieve plate; the burners are arranged on the 5 th layer to the 8 th layer from bottom to top of the high-temperature oxidation reactor 1, and 1-4 burners are uniformly arranged on the wall of each layer in the circumferential direction.
Preferably, when the liquid phase deep oxidation tower 8 is in a multi-layer bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 10-20, the layer spacing is 0.6-1.0 m, and the downcomer 37 is 0.1-0.6 m higher than a tower plate; when the liquid phase deep oxidation tower 8 is in a packing gas-liquid contact mode, the packing is a stepped ring or plate corrugated regular packing made of polypropylene plastics, and the height of the packing is 8-15 m.
Preferably, the average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.2 nm-1.8 nm.
Preferably, the number of layers of the sieve plate 18 in the high-temperature oxidation reactor 1 is 15, and the interlayer spacing is 0.5 m; the powder overflow downcomer 19 is higher than the sieve plate 180.25 m; the wall from the 5 th layer to the 8 th layer of the high-temperature oxidation reactor 1 from bottom to top is provided with a burner 23, and each layer is provided with 3-4 burners;
when the liquid phase deep oxidation tower 8 is in a multi-layer bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 16, the layer spacing is 0.8m, and the height of the downcomer 37 is 0.4m higher than a tower plate; when the liquid phase deep oxidation tower 8 is in a packing gas-liquid contact mode, the packing is a stepped ring or plate corrugated regular packing made of polypropylene plastics, and the height of the packing is 13 m;
the average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.5 nm.
A method for removing organic impurities in by-product sodium chloride salt by using the device comprises the following steps:
a. opening valves on an air inlet pipe 24 and a natural gas inlet pipe 25 on a combustor 23, igniting the combustor 23, starting to add salt powder with TOC content less than 3000mg/kg NaCl to the top of the high-temperature oxidation reactor 1 through a salt powder inlet 16 when the highest temperature in the high-temperature oxidation reactor 1, namely the hot spot temperature reaches 300 ℃, simultaneously opening the valve on an air inlet 21 and adjusting the air flow rate to enable the salt powder on the tower plate to be in a fluidized state, and enabling the salt powder to flow from top to bottom among the sieve plates 18 in each layer in the high-temperature oxidation reactor 1 through a powder overflow downcomer 19; the hot spot temperature of the high temperature oxidation reactor 1 is raised to the operating temperature by adjusting the air flow and the natural gas flow into each burner 23; the temperature of the hot spot is positioned in the middle of the high-temperature oxidation reactor 1; adjusting the feeding amount of the salt powder inlet 16 to ensure that the high-temperature oxidation reactor 1 achieves stable operation, wherein the retention time of the salt powder in the high-temperature oxidation reactor 1 is 10-30 min; the high-temperature combustion gas sprayed by the burner 23 is mixed with the air coming from the air inlet 21 to form high-temperature gas which is in fluidized contact with sodium chloride on the sieve plate 18, so that most organic impurities in the sodium chloride react with oxygen at high temperature to be oxidized, and then the high-temperature gas heats salt powder from top to bottom to reduce the temperature, and then the high-temperature gas is discharged from a flue gas discharge pipe 17 at the top of the high-temperature oxidation reactor 1;
b. salt powder coming out of a salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 enters a bucket elevator 2 from a salt powder hopper type lifting feed inlet 26, is lifted and conveyed by the bucket elevator 2, enters a dissolving kettle A3 from a bucket lifting discharge outlet 27 through a powder inlet A28 or enters a dissolving kettle B4 through a powder inlet B30, is added with dissolving water or unfiltered liquid from a filtered residual liquid outlet 44 on a fine filter 13 through a water inlet A29 or a water inlet B31, and is dissolved and prepared into a sodium chloride salt solution with the mass concentration of 17-30%; the dissolving kettle A3 and the dissolving kettle B4 are alternately used to realize the continuous operation of the subsequent process;
c. sodium chloride salt solution from a salt solution outlet A32 of the dissolving kettle A3 or a salt solution outlet B33 of the dissolving kettle B4 enters a centrifugal pump A5 for pressurization; if the TOC value in the sodium chloride salt solution is less than 20mg/kgNaCl according to the sodium chloride, the process directly enters the step e after passing through a flow regulation controller A34;
d. if the TOC value in terms of sodium chloride in the sodium chloride salt solution is more than or equal to 20mg/kgNaCl, the sodium chloride salt solution is pressurized by a centrifugal pump A5 and then enters a liquid-phase deep oxidation tower 8 from a salt solution inlet 35 through a flow regulation controller A34; the liquid oxidant from the discharge port of the oxidant storage tank 6 enters the liquid-phase deep oxidation tower 8 from the salt solution inlet 35 through a centrifugal pump B7 and a flow regulation controller B41; air containing the gas-phase oxidant enters the liquid-phase deep oxidation tower 8 from the gas inlet 38, fully contacts with the sodium chloride salt solution in a multi-layer bubbling mode, promotes the liquid oxidant and the gas-phase oxidant to cooperate with each other to deeply oxidize organic impurities in the sodium chloride salt solution, and then is discharged through the gas outlet 36; the sodium chloride solution flows from top to bottom in the liquid-phase deep oxidation tower 8 through a downcomer 37; the sodium chloride salt solution from the sodium chloride solution outlet 39 at the bottom of the liquid-phase deep oxidation tower 8 is pressurized by a pressurizing pump A9 and flow regulation is carried out by a flow regulation controller C42;
e. the sodium chloride solution enters a filter pressing feed inlet 40 of the liquid-solid filter 10, and original solid impurities in the sodium chloride solution and residual carbon and other particulate matters in the combustion process are removed through the filtering action; the filtrate obtained by the liquid-solid filter 10 enters a pressurizing pump B12 from a discharge port to be pressurized; if the TOC value in the filtrate is less than 20mg/kgNaCl according to the sodium chloride, the filtrate is directly sent to an ion membrane caustic soda industrial device 15; the filter cake filtered by the liquid-solid filter 10 enters a solid slag groove 11;
f. when the TOC value in the filtrate is more than or equal to 20mg/kgNaCl according to sodium chloride, the filtrate pressurized by a pressurizing pump B12 enters an inlet of a fine filter 13, and unoxidized macromolecular organic matter impurities in the sodium chloride salt solution are further removed by filtering through a nanofiltration membrane to obtain a sodium chloride solution; the solution left after filtration returns to the dissolving kettle A3 or the dissolving kettle B4 through a filtrate residue outlet 44;
g. when the TOC value of the sodium chloride solution obtained from the fine filter 13 is less than 20mg/kgNaCl according to the sodium chloride, the sodium chloride solution is sent to an ionic membrane caustic soda industrial device 15 from a filtrate outlet 45 through a delivery pump 14, otherwise, the sodium chloride solution returns to a dissolving kettle A3 or a dissolving kettle B4.
Preferably, the operating temperature in the step a is 350-820 ℃, the residence time of the salt powder in the high-temperature oxidation reactor 1 is 15-25 min, the oxygen content of the high-temperature gas is 5.0-16.0%, and the air velocity of the air tower in the high-temperature oxidation reactor 1 is 0.3-0.6 m/s; the total carbon content TOC in the salt powder from the salt powder outlet 22 of the high-temperature oxidation reactor 1 is 10 mg/kgNaCl-200 mg/kgNaCl according to the sodium chloride.
Preferably, the sodium chloride solution in the step b has a sodium chloride mass concentration of 20-25%.
Preferably, the liquid oxidant in step d is hydrogen peroxide or sodium hypochlorite, and the mass concentration of the liquid oxidant is 10-30%; the mass flow rate of the sodium chloride solution entering the liquid-phase deep oxidation tower 8 and the mass flow rate of the liquid oxidant are 100: 1-100: 5, and the liquid-phase solution formed by combining the sodium chloride solution and the liquid oxidant is retained in the liquid-phase deep oxidation tower 8 for 5-30 min from top to bottom; the air velocity of the air in the liquid phase deep oxidation tower 8 is 0.1-0.4 m/s; the gas-phase oxidant is ozone or chlorine, and the molar content of the gas-phase oxidant in the air is 1.0-5.0%; the reaction temperature in the liquid-phase deep oxidation tower 8 is 15-60 ℃; the TOC value of the sodium chloride salt solution is 10 mg/kgNaCl-60 mg/kgNaCl according to the sodium chloride.
Preferably, the TOC value of the filtrate in the step e is 5 mg/kgNaCl-40 mg/kgNaCl according to sodium chloride, and the TOC value of the sodium chloride solution in the step f is less than 20mg/kgNaCl according to sodium chloride.
Example 1:
the diameter of the high-temperature oxidation reactor 1 is 1m, the total height is 15m, the number of layers of the sieve plate 18 is 18, and the interlayer spacing is 0.6 m; the particle overflow downcomer 19 is 180.4m higher than the sieve plate, 4 burners 23 are arranged on the wall from the 5 th layer to the 8 th layer from bottom to top, and 1 burner is arranged on each layer. The volumes of the dissolving kettle A3 and the dissolving kettle B4 are both 10m3. The diameter of the liquid phase deep oxidation tower 8 is 1.8m, the total height is 15m, the liquid phase deep oxidation tower is in a multi-layer sieve plate bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 12, the interlayer spacing is 1.0m, and the downcomer 37 is 0.5m higher than a tower plate. The average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.2 nm.
The valves of the air inlet pipe 24 and the fuel gas inlet pipe 25 of the combustor 23 are opened, the combustor 23 is ignited at the same time, and salt powder with total carbon content TOC of 1400mg/kg NaCl calculated according to sodium chloride is continuously added through the salt powder inlet 16 when the hot spot temperature in the high-temperature oxidation reactor 1 reaches 300 ℃. The air inlet 21 valve is opened and the air flow is adjusted so that the salt powder on the tray is in a fluidized state. The hot spot temperature of the high temperature oxidation reactor 1 was raised to 450 c by adjusting the air flow rate and the natural gas flow rate into each burner 23. The oxygen content in the high-temperature gas is 14.1 percent, and the superficial gas velocity in the high-temperature oxidation reactor 1 is 0.42 m/s. The feeding amount of the salt powder inlet 16 and the discharging amount of the salt powder outlet 22 are respectively adjusted to be 141kg/min, and the salt powder in the high-temperature oxidation reactor 1 is enabled to reach a stable fluidization operation state. The total residence time of the salt powder in the high-temperature oxidation reactor 1 was 31 min. The total carbon content TOC in the salt powder coming out of the salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 is 177mg/kgNaCl according to the sodium chloride.
The salt powder is lifted and conveyed by a bucket elevator 2, 2500kg of salt powder is added into a dissolving kettle A3, and water is added for dissolving to prepare sodium chloride solution with the mass concentration of 28 percent. Then dissolving tank A3 and dissolving tank B4 were used alternately to achieve continuous operation of the subsequent process. Then is sent into a liquid phase deep oxidation tower 8 through a centrifugal pump A5 and a flow regulation controller A34, and the flow is controlled to be 21.4m3H is used as the reference value. The hydrogen peroxide solution with the mass concentration of 30 percent in the oxidant storage tank 6 enters the liquid-phase deep oxidation tower 8 together with the sodium chloride solution through a centrifugal pump B7 and a flow regulation controller B41. The ratio of the mass flow of the sodium chloride solution to the mass flow of the liquid oxidant is 100:2.5, and the retention time of the solution in the tower from top to bottom is 30 min. Containing O3Air with the volume concentration of 2.0 percent enters the liquid phase deep oxidation tower 8 from a gas inlet 38, and the air velocity of the air tower is 0.25 m/s. The reaction temperature in the liquid phase deep oxidation tower 8 was 30 ℃. In the sodium chloride salt solution discharged from the sodium chloride solution outlet 39 at the bottom of the liquid-phase deep oxidation tower 8, the TOC value is 56mg/kgNaCl in terms of sodium chloride.
The sodium chloride salt solution enters the liquid-solid filter 10 through a pressurizing pump A9 and a flow regulating controller C42. The filtrate is fed into a fine filter 13 through a pressure pump B12 to obtain a sodium chloride solution, wherein the TOC value is 18.3mg/kgNaCl according to the sodium chloride, and the sodium chloride solution is sent to an ion membrane caustic soda industrial device 15 through a delivery pump 14. The solution remaining after the filtration is returned to dissolution tank a3 or dissolution tank B4 through filtration residue outlet 44.
Example 2:
the diameter of the high-temperature oxidation reactor 1 is 1m, the total height is 12m, the number of layers of the sieve plate 18 is 16, and the interlayer spacing is 0.55 m; the powder overflow downcomer 19 is higher than the sieve plate 180.35m, 4 burners 23 are installed on the wall from the 5 th layer to the 8 th layer from bottom to top, and 1 burner is installed on each layer. The volumes of the dissolving kettle A3 and the dissolving kettle B4 are both 10m3. The diameter of the liquid phase deep oxidation tower 8 is 1.6m, the total height is 14m, the tower is in a multi-layer sieve plate bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 14, and the interlayer spacing is 0.8m, the downcomer 37 is 0.45m above the tray. The average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.6 nm.
The valves of the air inlet pipe 24 and the fuel gas inlet pipe 25 of the combustor 23 are opened, the combustor 23 is ignited at the same time, and salt powder with total carbon content TOC of 1500mg/kg NaCl calculated according to sodium chloride is continuously added through the salt powder inlet 16 when the hot spot temperature in the high-temperature oxidation reactor 1 reaches 300 ℃. The air inlet 21 valve is opened and the air flow is adjusted so that the salt powder on the tray is in a fluidized state. The hot spot temperature of the high temperature oxidation reactor 1 was raised to 550 c by adjusting the air flow rate and the natural gas flow rate into each burner 23. The oxygen content in the high-temperature gas is 13.2 percent, and the empty tower gas velocity in the high-temperature oxidation reactor 1 is 0.35 m/s. The feeding amount of the salt powder inlet 16 and the discharging amount of the salt powder outlet 22 are respectively adjusted to reach 176kg/min, and the salt powder in the high-temperature oxidation reactor 1 is enabled to reach a stable fluidization operation state. The total residence time of the salt powder in the high-temperature oxidation reactor 1 was 22 min. The total carbon content TOC in the salt powder coming out of the salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 is 133mg/kgNaCl according to the sodium chloride.
The salt powder is lifted and conveyed by a bucket elevator 2, 2500kg of salt powder is added into a dissolving kettle A3, and sodium chloride solution with the mass concentration of 27% is prepared by adding water for dissolving. Then dissolving tank A3 and dissolving tank B4 were used alternately to achieve continuous operation of the subsequent process. Then is sent into a liquid phase deep oxidation tower 8 through a centrifugal pump A5 and a flow regulation controller A34, and the flow is controlled to be 21.3m3H is used as the reference value. Sodium hypochlorite solution with the mass concentration of 10% in the oxidant storage tank 6 enters the liquid-phase deep oxidation tower 8 together with sodium chloride solution through a centrifugal pump B7 and a flow regulation controller B41. The ratio of the mass flow of the sodium chloride solution to the mass flow of the liquid oxidant is 100:3.5, and the retention time of the solution in the tower from top to bottom is 25 min. Containing O3Air with the volume concentration of 1.5 percent enters the liquid phase deep oxidation tower 8 from a gas inlet 38, and the air velocity of the air tower is 0.14 m/s. The reaction temperature in the liquid phase deep oxidation tower 8 was 35 ℃. The TOC value is 53mg/kgNaC according to the sodium chloride in the sodium chloride solution from the sodium chloride solution outlet 39 at the bottom of the liquid-phase deep oxidation tower 8l。
The sodium chloride salt solution enters the liquid-solid filter 10 through a pressurizing pump A9 and a flow regulating controller C42. The filtrate is fed into a fine filter 13 through a pressure pump B12 to obtain a sodium chloride solution, wherein the TOC value is 17.3mg/kgNaCl according to the sodium chloride, and the sodium chloride solution is sent to an ion membrane caustic soda industrial device 15 through a delivery pump 14. The solution remaining after the filtration is returned to dissolution tank a3 or dissolution tank B4 through filtration residue outlet 44.
Example 3:
the diameter of the high-temperature oxidation reactor 1 is 1m, the total height is 12m, the number of layers of the sieve plate 18 is 16, and the interlayer spacing is 0.5 m; the particle overflow downcomer 19 is higher than the sieve plate 180.32m, 6 burners 23 are installed on the wall from the 5 th layer to the 8 th layer from bottom to top, 2 burners are respectively installed on the 5 th layer and the 7 th layer, and 1 burner is installed on the 6 th layer and the 8 th layer. The volumes of the dissolving kettle A3 and the dissolving kettle B4 are both 10m3. The diameter of the liquid phase deep oxidation tower 8 is 1.6m, the total height is 16m, the liquid phase deep oxidation tower is in a packing type gas-liquid contact mode, and the height of a packing layer is 10 m. The average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.5 nm.
The valves of the air inlet pipe 24 and the fuel gas inlet pipe 25 of the burner 23 are opened, the burner 23 is ignited at the same time, and salt powder with total carbon content TOC of 1800mg/kg NaCl calculated according to sodium chloride is continuously added through the salt powder inlet 16 when the hot spot temperature in the high-temperature oxidation reactor 1 reaches 300 ℃. The air inlet 21 valve is opened and the air flow is adjusted so that the salt powder on the tray is in a fluidized state. The hot spot temperature of the high temperature oxidation reactor 1 was raised to 600 c by adjusting the air flow rate and the natural gas flow rate into each burner 23. The oxygen content in the high-temperature gas is 12.3 percent, and the air velocity in the high-temperature oxidation reactor 1 is 0.30 m/s. The feeding amount of the salt powder inlet 16 and the discharging amount of the salt powder outlet 22 are respectively adjusted to reach 200kg/min, and the salt powder in the high-temperature oxidation reactor 1 is enabled to reach a stable fluidization operation state. The total residence time of the salt powder in the high-temperature oxidation reactor 1 was 15 min. The total carbon content TOC in the salt powder coming out of the salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 is 85mg/kgNaCl according to the sodium chloride.
The salt powder is lifted and conveyed by a bucket elevator 2, 2500kg of salt powder is added into a dissolving kettle A3, and sodium chloride solution with the mass concentration of 25% is prepared by adding water for dissolving. Then dissolving tank A3 and dissolving tank B4 were used alternately to achieve continuous operation of the subsequent process. Then sent into a liquid phase deep oxidation tower 8 through a centrifugal pump A5 and a flow regulation controller A34, wherein the flow is controlled to be 30m3H is used as the reference value. The hydrogen peroxide solution with the mass concentration of 30 percent in the oxidant storage tank 6 enters the liquid-phase deep oxidation tower 8 together with the sodium chloride solution through a centrifugal pump B7 and a flow regulation controller B41. The ratio of the mass flow of the sodium chloride solution to the mass flow of the liquid oxidant is 100:2.0, and the retention time of the solution in the tower from top to bottom is 20 min. Containing Cl2Air with the volume concentration of 2.5 percent enters the liquid phase deep oxidation tower 8 from a gas inlet 38, and the air velocity of the air tower is 0.21 m/s. The reaction temperature in the liquid phase deep oxidation tower 8 was 40 ℃. The TOC value in terms of sodium chloride in the sodium chloride salt solution discharged from the sodium chloride solution outlet 39 at the bottom of the liquid-phase deep oxidation tower 8 is 41 mg/kgNaCl.
The sodium chloride salt solution enters the liquid-solid filter 10 through a pressurizing pump A9 and a flow regulating controller C42. The filtrate is fed into a fine filter 13 through a pressure pump B12 to obtain a sodium chloride solution, wherein the TOC value is 16.2mg/kgNaCl according to the sodium chloride, and the sodium chloride solution is sent to an ion membrane caustic soda industrial device 15 through a delivery pump 14. The solution remaining after the filtration is returned to dissolution tank a3 or dissolution tank B4 through filtration residue outlet 44.
Example 4:
the diameter of the high-temperature oxidation reactor 1 is 1m, the total height is 12m, the number of layers of the sieve plate 18 is 16, and the interlayer spacing is 0.5 m; the particle overflow downcomer 19 is higher than the sieve plate 180.25m, 6 burners 23 are installed on the wall from the 5 th layer to the 8 th layer from bottom to top, 2 burners are respectively installed on the 5 th layer and the 7 th layer, and 1 burner is installed on the 6 th layer and the 8 th layer. The volumes of the dissolving kettle A3 and the dissolving kettle B4 are both 10m3. The diameter of the liquid phase deep oxidation tower 8 is 1.5m, the total height is 18m, the liquid phase deep oxidation tower is in a packing type gas-liquid contact mode, and the height of a packing layer is 12 m. The average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.4 nm.
The valves of the air inlet pipe 24 and the fuel gas inlet pipe 25 of the combustor 23 are opened, the combustor 23 is ignited at the same time, and salt powder with total carbon content TOC of 2000mg/kg NaCl calculated according to sodium chloride is continuously added through the salt powder inlet 16 when the hot spot temperature in the high-temperature oxidation reactor 1 reaches 300 ℃. The air inlet 21 valve is opened and the air flow is adjusted so that the salt powder on the tray is in a fluidized state. The hot spot temperature of the high temperature oxidation reactor 1 was raised to 700 c by adjusting the air flow rate and the natural gas flow rate into each burner 23. The oxygen content in the high-temperature gas is 10.8 percent, and the air velocity of the empty tower in the high-temperature oxidation reactor 1 is 0.25 m/s. The feeding amount of the salt powder inlet 16 and the discharging amount of the salt powder outlet 22 are respectively adjusted to reach 200kg/min, and the salt powder in the high-temperature oxidation reactor 1 is enabled to reach a stable fluidization operation state. The total residence time of the salt powder in the high-temperature oxidation reactor 1 was 10 min. The total carbon content TOC in the salt powder coming out of the salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 is 48mg/kgNaCl according to the sodium chloride.
The salt powder is lifted and conveyed by a bucket elevator 2, 2500kg of salt powder is added into a dissolving kettle A3, and sodium chloride solution with the mass concentration of 25% is prepared by adding water for dissolving. Then dissolving tank A3 and dissolving tank B4 were used alternately to achieve continuous operation of the subsequent process. Then sent into a liquid phase deep oxidation tower 8 through a centrifugal pump A5 and a flow regulation controller A34, wherein the flow is controlled to be 35m3H is used as the reference value. Sodium hypochlorite solution with the mass concentration of 10% in the oxidant storage tank 6 enters the liquid-phase deep oxidation tower 8 together with sodium chloride solution through a centrifugal pump B7 and a flow regulation controller B41. The ratio of the mass flow of the sodium chloride solution to the mass flow of the liquid oxidant is 100:1.5, and the retention time of the solution in the tower from top to bottom is 18 min. Containing Cl2Air with volume concentration of 3.0 percent enters the liquid phase deep oxidation tower 8 from a gas inlet 38, and the air velocity of the air tower is 0.27 m/s. The reaction temperature in the liquid-phase deep oxidation tower 8 was 45 ℃. In the sodium chloride salt solution discharged from the sodium chloride solution outlet 39 at the bottom of the liquid-phase deep oxidation tower 8, the TOC value in terms of sodium chloride is 28 mg/kgNaCl.
The sodium chloride salt solution enters the liquid-solid filter 10 through a pressurizing pump A9 and a flow regulating controller C42. The TOC value in the filtrate is 19.2mg/kgNaCl according to the sodium chloride, and then the TOC value is directly sent to an ion membrane caustic soda industrial device 15 through a pressure pump B12.
Example 5
The diameter of the high-temperature oxidation reactor 1 is 0.8m, the total height is 12m, the number of layers of the sieve plate 18 is 16, and the interlayer spacing is 0.45 m; the powder overflow downcomer 19 is higher than the sieve plate 180.18m, 8 burners 23 are arranged on the wall from the 5 th layer to the 8 th layer from bottom to top, and 2 burners are arranged on each layer. The volumes of the dissolving kettle A3 and the dissolving kettle B4 are both 10m3. The average pore diameter of the nanofiltration membrane of the fine filter 13 is 1.4 nm.
The valves of the air inlet pipe 24 and the fuel gas inlet pipe 25 of the combustor 23 are opened, the combustor 23 is ignited at the same time, and salt powder with total carbon content TOC of 2400mg/kg NaCl calculated according to sodium chloride is continuously added through the salt powder inlet 16 when the hot spot temperature in the high-temperature oxidation reactor 1 reaches 300 ℃. The air inlet 21 valve is opened and the air flow is adjusted so that the salt powder on the tray is in a fluidized state. The hot spot temperature of the high temperature oxidation reactor 1 was raised to 750 ℃ by adjusting the air flow rate and the natural gas flow rate into each burner 23. The oxygen content in the high-temperature gas is 9.5 percent, and the empty tower gas velocity in the high-temperature oxidation reactor 1 is 0.18 m/s. The feeding amount of the salt powder inlet 16 and the discharging amount of the salt powder outlet 22 are respectively adjusted to 120kg/min, and the salt powder in the high-temperature oxidation reactor 1 is enabled to reach a stable fluidization operation state. The total residence time of the salt powder in the high-temperature oxidation reactor 1 was 8 min. The total carbon content TOC in the salt powder from the salt powder outlet 22 at the bottom of the high-temperature oxidation reactor 1 is 18.9mg/kg NaCl in terms of sodium chloride.
The salt powder is lifted and conveyed by a bucket elevator 2, 2500kg of salt powder is added into a dissolving kettle A3, and sodium chloride solution with the mass concentration of 25% is prepared by adding water for dissolving. Then dissolving tank A3 and dissolving tank B4 were used alternately to achieve continuous operation of the subsequent process. The liquid-solid filter 10 is then fed through centrifugal pump a5 and flow regulator a 34. The filtrate enters a fine filter 13 through a pressure pump B12 to obtain a sodium chloride solution, and then is sent to an ionic membrane caustic soda industrial device 15 through a transfer pump 14. The solution remaining after the filtration is returned to dissolution tank a3 or dissolution tank B4 through filtration residue outlet 44.
Claims (5)
1. A device for removing organic impurities in byproduct sodium chloride salt is characterized by comprising a high-temperature oxidation reactor (1), a dissolving kettle A (3), a dissolving kettle B (4), an oxidant storage tank (6), a liquid-phase deep oxidation tower (8), a liquid-solid filter (10), a solid slag tank (11) and a fine filter (13) which are connected in sequence;
the high-temperature oxidation reactor (1) is a fluidized bed with a plurality of layers, each layer is provided with a sieve plate (18), and a powder overflow downcomer (19) is arranged on each sieve plate (18); 4-16 burners (23) are arranged on the wall of the lower middle part of the high-temperature oxidation reactor (1), a flue gas discharge pipe (17) is arranged at the top, an air inlet (21) and a sloping plate type gas distribution plate (20) at the corresponding position in the fluidized bed are arranged on the side surface of the lower part, a salt powder inlet (16) is arranged on the side surface of the upper part, and a salt powder outlet (22) is arranged on the side surface of the lower part; each combustor (23) is respectively provided with an air inlet pipe (24) and a gas inlet pipe (25); the salt powder outlet (22) is connected with a bucket type lifting feed inlet (26) at the bottom of the bucket type lifter (2) through a pipeline;
the dissolving kettle A (3) is a stirring kettle, the top of the dissolving kettle is provided with a powder inlet A (28) and a water inlet A (29), and the bottom of the dissolving kettle is provided with a salt solution outlet A (32); the dissolving kettle B (4) is a stirring kettle, the top of the dissolving kettle B is provided with a powder inlet B (30) and a water inlet B (31), and the bottom of the dissolving kettle B is provided with a salt solution outlet B (33); the powder inlet A (28) and the powder inlet B (30) are respectively connected with a bucket type lifting discharge port (27) at the top of the bucket type lifter (2); the saline solution outlet A (32) and the saline solution outlet B (33) are respectively connected with the inlet of the centrifugal pump A (5) through valves; the outlet of the centrifugal pump A (5) is connected with the inlet of the flow regulating controller A (34);
the liquid phase deep oxidation tower (8) is a tower reactor, and the gas-liquid contact form is a multilayer bubbling gas-liquid contact form or a filler gas-liquid contact form; the side surface of the upper part of the liquid phase deep oxidation tower (8) is provided with a salt solution inlet (35), the side surface of the lower part is provided with a gas inlet (38), the bottom of the liquid phase deep oxidation tower is provided with a sodium chloride solution outlet (39), and the top of the liquid phase deep oxidation tower is provided with a gas outlet (36); the salt solution inlet (35) is connected with the outlets of the flow regulating controller A (34) and the flow regulating controller B (41); a discharge port at the lower part of the oxidant storage tank (6) is connected with an inlet of a flow regulating controller B (41) through a centrifugal pump B (7); the sodium chloride solution outlet (39) is connected with the inlet of the pressure pump A (9); the outlet of the pressure pump A (9) is connected with the inlet of a flow regulating controller C (42);
a downcomer (37) is arranged in the liquid phase deep oxidation tower (8), and the downcomer (37) is cylindrical or sector cylindrical;
the liquid-solid filter (10) is a plate-and-frame filter press, a filter pressing feed inlet (40) of the liquid-solid filter is connected with an outlet of a flow regulating controller C (42), and a filtrate outlet of the liquid-solid filter (10) is connected with an inlet of a pressure pump B (12); the outlet of the pressure pump B (12) is connected with the inlet of a flow regulating controller D (43);
the fine filter (13) is a nanofiltration membrane filter, the inlet of the fine filter is connected with the outlet of a flow regulating controller D (43), the filtrate outlet (45) is connected with the inlet of a delivery pump (14), and the filtered residual liquid outlet (44) is connected with the top water inlet A (29) of the dissolving kettle A (3) and the top water inlet B (31) of the dissolving kettle B (4); the outlet of the delivery pump (14) is connected with a subsequent ionic membrane caustic soda industrial device (15);
the outlet of the flow regulating controller A (34) is directly connected with a filter pressing feed inlet (40) of the liquid-solid filter (10) through a valve; the outlet of the flow regulating controller D (43) can be directly connected with a subsequent ionic membrane caustic soda industrial device (15) through a valve;
the number of layers of the sieve plate (18) in the high-temperature oxidation reactor (1) is 10-20, and the interlayer spacing is 0.4-0.6 m; the particle overflow downcomer (19) is 0.1-0.4 m higher than the sieve plate (18); the burners are arranged on the 5 th layer to the 8 th layer from bottom to top of the high-temperature oxidation reactor (1), and 1-4 burners are uniformly distributed on the wall of each layer in the circumferential direction.
2. The device for removing organic impurities in by-product sodium chloride salt according to claim 1, wherein when the liquid phase deep oxidation tower (8) is in a multi-layer bubbling gas-liquid contact mode, the number of gas-liquid contact layers is 10-20, the layer spacing is 0.6-1.0 m, and the downcomer (37) is 0.1-0.6 m higher than a tower plate; when the liquid phase deep oxidation tower (8) is in a packing gas-liquid contact mode, the packing is stepped ring or plate corrugated regular packing made of polypropylene plastics, and the height of the packing is 8-15 m.
3. A method for removing organic impurities in by-product sodium chloride salt by using the device of claim 1, which is characterized by comprising the following steps:
a. starting valves on an air inlet pipe (24) and a natural gas inlet pipe (25) on a combustor (23), igniting the combustor (23), starting to add salt powder with TOC content of less than 3000mg/kg NaCl to the top of the high-temperature oxidation reactor (1) through a salt powder inlet (16) when the highest temperature in the high-temperature oxidation reactor (1), namely the hot spot temperature reaches 300 ℃, simultaneously starting the valve on an air inlet (21) and adjusting the air flow to enable the salt powder on the tower plates to be in a fluidized state, and enabling the salt powder to flow from top to bottom among the sieve plates (18) in each layer in the high-temperature oxidation reactor (1) through a powder overflow downcomer (19); raising the hot spot temperature of the high temperature oxidation reactor (1) to an operating temperature by adjusting the air flow and the natural gas flow into each burner (23); the temperature of the hot spot is positioned in the middle of the high-temperature oxidation reactor (1); adjusting the feeding amount of the salt powder inlet (16) to ensure that the high-temperature oxidation reactor (1) achieves stable operation, wherein the retention time of the salt powder in the high-temperature oxidation reactor (1) is 10-30 min; high-temperature combustion gas sprayed by a burner (23) is mixed with air coming from an air inlet (21) to form high-temperature gas which is in fluidized contact with sodium chloride on a sieve plate (18), so that most of organic impurities in the sodium chloride react with oxygen at high temperature to be oxidized, and then the high-temperature gas heats salt powder from top to bottom to reduce the temperature, and then the high-temperature gas is discharged from a flue gas discharge pipe (17) at the top of a high-temperature oxidation reactor (1);
b. salt powder discharged from a salt powder outlet (22) at the bottom of a high-temperature oxidation reactor (1) enters a bucket elevator (2) from a salt powder hopper type lifting feed inlet (26), is lifted and conveyed by the bucket elevator (2), enters a dissolving kettle A (3) from a bucket lifting discharge outlet (27) through a powder inlet A (28) or enters a dissolving kettle B (4) through a powder inlet B (30), is added with dissolving water or unfiltered liquid from a filtered residual liquid outlet (44) on a fine filter (13) through a water inlet A (29) or a water inlet B (31), and is dissolved to prepare a sodium chloride salt solution with the mass concentration of 17-30%; the dissolving kettle A (3) and the dissolving kettle B (4) are alternately used to realize the continuous operation of the subsequent process;
c. sodium chloride salt solution coming out of a salt solution outlet A (32) of the dissolving kettle A (3) or a salt solution outlet B (33) of the dissolving kettle B (4) enters a centrifugal pump A (5) to be pressurized; if the TOC value in the sodium chloride salt solution is less than 20mg/kgNaCl according to the sodium chloride, the step e is directly carried out after passing through a flow regulation controller A (34);
d. if the TOC value in sodium chloride solution is more than or equal to 20mg/kgNaCl according to sodium chloride, the pressurized sodium chloride solution enters a liquid-phase deep oxidation tower (8) from a salt solution inlet (35) through a flow regulation controller A (34) after being pressurized by a centrifugal pump A (5); liquid oxidant from a discharge hole of the oxidant storage tank (6) enters a liquid-phase deep oxidation tower (8) from a salt solution inlet (35) through a centrifugal pump B (7) and a flow regulating controller B (41); air containing a gas-phase oxidant enters the liquid-phase deep oxidation tower (8) from the gas inlet (38) and is fully contacted with the sodium chloride salt solution in a multi-layer bubbling mode, so that the liquid oxidant and the gas-phase oxidant are promoted to cooperate with each other to deeply oxidize organic impurities in the sodium chloride salt solution, and then the air is discharged through the gas outlet (36); the sodium chloride solution flows from top to bottom in the liquid-phase deep oxidation tower (8) through a downcomer (37); sodium chloride solution from a sodium chloride solution outlet (39) at the bottom of the liquid-phase deep oxidation tower (8) is pressurized by a pressurizing pump A (9) and flow regulation is carried out by a flow regulation controller C (42);
e. the sodium chloride solution enters a filter pressing feed inlet (40) of a liquid-solid filter (10), and original solid impurities in the sodium chloride solution and residual carbon and other particulate matters in the combustion process are removed through the filtering action; the filtrate obtained by the liquid-solid filter (10) enters a pressurizing pump B (12) from a discharge hole to be pressurized; if the TOC value in the filtrate is less than 20mg/kg NaCl according to the sodium chloride, the filtrate is directly sent to an ion membrane caustic soda industrial device (15); filter cakes filtered out by the liquid-solid filter (10) enter a solid slag groove (11);
f. when the TOC value in the filtrate is more than or equal to 20mg/kgNaCl according to sodium chloride, the filtrate pressurized by a pressurizing pump B (12) enters an inlet of a fine filter (13), and unoxidized macromolecular organic matter impurities in the sodium chloride salt solution are further removed by filtering through a nanofiltration membrane to obtain a sodium chloride solution; the solution left after filtration returns to the dissolving kettle A (3) or the dissolving kettle B (4) through a filtration residual solution outlet (44);
g. when the TOC value of the sodium chloride solution obtained from the fine filter (13) is less than 20mg/kgNaCl according to the sodium chloride, the sodium chloride solution is sent to an ionic membrane caustic soda industrial device (15) from a filtrate outlet (45) through a delivery pump (14), otherwise, the sodium chloride solution returns to the dissolving kettle A (3) or the dissolving kettle B (4).
4. The method for removing organic impurities in by-product sodium chloride salt according to claim 3, wherein the operating temperature in step a is 350-820 ℃, the residence time of the salt powder in the high-temperature oxidation reactor (1) is 15-25 min, the oxygen content of the high-temperature gas is 5.0-16.0%, and the air velocity of the hollow tower in the high-temperature oxidation reactor (1) is 0.3-0.6 m/s; the total carbon content TOC in the salt powder material discharged from the salt powder material outlet (22) of the high-temperature oxidation reactor (1) is 10mg/kg NaCl-200 mg/kg NaCl according to the sodium chloride.
5. The method for removing organic impurities in byproduct sodium chloride salt according to claim 4, wherein the liquid oxidant in the step d is hydrogen peroxide or sodium hypochlorite, and the mass concentration of the liquid oxidant is 10-30%; the ratio of the mass flow rate of the sodium chloride solution entering the liquid-phase deep oxidation tower (8) to the mass flow rate of the liquid oxidant is 100: 1-100: 5, and the liquid-phase solution formed by combining the sodium chloride solution and the liquid oxidant solution stays in the liquid-phase deep oxidation tower (8) for 5-30 min from top to bottom; the air velocity of the air in the liquid phase deep oxidation tower (8) is 0.1-0.4 m/s; the gas-phase oxidant is ozone or chlorine, and the molar content of the gas-phase oxidant in the air is 1.0-5.0%; the reaction temperature in the liquid-phase deep oxidation tower (8) is 15-60 ℃; the TOC value of the sodium chloride salt solution is 10 mg/kgNaCl-60 mg/kgNaCl according to the sodium chloride.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910240118.4A CN109956485B (en) | 2019-03-27 | 2019-03-27 | Device and method for removing organic matter impurities in byproduct sodium chloride salt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910240118.4A CN109956485B (en) | 2019-03-27 | 2019-03-27 | Device and method for removing organic matter impurities in byproduct sodium chloride salt |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109956485A CN109956485A (en) | 2019-07-02 |
| CN109956485B true CN109956485B (en) | 2022-04-05 |
Family
ID=67025181
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910240118.4A Active CN109956485B (en) | 2019-03-27 | 2019-03-27 | Device and method for removing organic matter impurities in byproduct sodium chloride salt |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109956485B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109956484B (en) * | 2019-03-27 | 2022-04-05 | 河北科技大学 | Organic matter impurity removing device in chlorinator process by-product sodium chloride salt |
| CN111646487B (en) * | 2020-06-04 | 2021-06-15 | 山东智永化工产业技术研究院有限公司 | Resource method for treating chemical waste salt |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE1016681A3 (en) * | 2005-07-14 | 2007-04-03 | Bio Olie Belgie Bv | METHOD FOR REMEDIATING GROUND. |
| CN105692986B (en) * | 2014-11-24 | 2018-12-28 | 中国石油化工股份有限公司 | A kind of processing method of abraum salt comprehensive utilization |
| CN104649495B (en) * | 2015-02-13 | 2017-03-08 | 江苏中丹集团股份有限公司 | A kind of chemical engineering industry abraum salt process for refining |
| CN109956484B (en) * | 2019-03-27 | 2022-04-05 | 河北科技大学 | Organic matter impurity removing device in chlorinator process by-product sodium chloride salt |
-
2019
- 2019-03-27 CN CN201910240118.4A patent/CN109956485B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109956485A (en) | 2019-07-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111285335B (en) | System for preparing sulfuric acid by using sulfur foam and desulfurization waste liquid semidry method and acid preparation method | |
| CN109956485B (en) | Device and method for removing organic matter impurities in byproduct sodium chloride salt | |
| CN109956484B (en) | Organic matter impurity removing device in chlorinator process by-product sodium chloride salt | |
| JPH08109004A (en) | Transferring and partially oxidative processing apparatus and method for conversion of low value hydrocarbon at low temperature | |
| CN109575996B (en) | Method for preparing synthesis gas by co-gasification of coal and heavy oil | |
| US5670061A (en) | Process for treating ash | |
| CN113266834A (en) | Organic industrial waste salt treatment method, melting bed and treatment system | |
| CN210523361U (en) | Waste salt resourceful treatment processing system | |
| US6033637A (en) | Method for treating combustion ashes | |
| CN110079361A (en) | The method and its equipment of the non-slag gasification production hydrogen-rich synthetic gas of petroleum coke | |
| CN105080933A (en) | Treatment method of organic solid wastes | |
| CN114014468A (en) | System and method applied to pretreatment of coke oven gas desulfurization waste liquid | |
| CN212403511U (en) | Thermal cracking treatment system of high concentration COD organic waste liquid | |
| CN113292191A (en) | Residual oil catalytic pyrolysis and coal-to-olefin waste alkali liquor resource utilization device | |
| CN210559811U (en) | Catalyst separation device for acrylonitrile quenching water | |
| CN114812156A (en) | Waste salt pyrolysis treatment system and method based on multi-hearth furnace | |
| CN110683520B (en) | Process for preparing sulfuric acid by regenerating low-concentration dilute waste sulfuric acid | |
| CN210065682U (en) | Petroleum coke entrained-flow bed gasification furnace | |
| CN107670633B (en) | Method for treating organic wastewater | |
| CN110822444A (en) | Application of white mud in waste incineration treatment and waste incineration treatment method | |
| CN110862197A (en) | Method and device for treating residual ammonia water in coking industry | |
| CN114057277A (en) | Waste alkali wet oxidation system and method | |
| CN111268884B (en) | Oil sludge treatment system and method | |
| CN214611894U (en) | Reaction system for treating high-concentration organic waste liquid | |
| CN214936760U (en) | Residual oil catalytic thermal cracking and coal-to-olefin waste alkali liquor resource utilization device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |