CN-122007128-A - Solid waste salt disposal system and method

CN122007128ACN 122007128 ACN122007128 ACN 122007128ACN-122007128-A

Abstract

The embodiment of the disclosure discloses a solid waste salt disposal system, belonging to the technical field of waste salt recovery treatment. The device comprises a pyrolysis system and a flue gas treatment system, wherein the pyrolysis system and the flue gas treatment system are used for carrying out secondary pyrolysis on waste salt and simultaneously reversely providing a hot air treatment mode, harmful substances in the waste salt are separated from solids to form flue gas, and the purposes of recycling the waste salt and decomposing the harmful substances are achieved through a flue gas purification process, so that the harmless purpose is achieved.

Inventors

XIA TIANTIAN
LI LIANG
HU XIAOWEI
ZHAO MINGYU
GUO LIMIN
LI SHENG
YU HAIYANG
Song Xuntao

Assignees

中洁蓝环保科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260206

Claims (10)

1. A solid waste salt disposal system, the system comprising The pyrolysis system comprises a secondary thermal kiln system, a cooling kiln and a hot air system which are connected in series step by step, waste salt is pyrolyzed by step heating and pyrolyzing and then cooling, the hot air system is reversely introduced into a secondary kiln of the secondary thermal kiln system, pyrolysis smoke is formed by passing through a primary kiln, the pyrolysis smoke enters a smoke treatment system, and materials of the secondary thermal kiln system enter an assay tank of a salt dissolving and separating system through spiral discharging; the flue gas treatment system comprises a secondary combustion chamber, a waste heat boiler, a quenching tower, a bag-type dust remover, a waste acid recovery unit and a water washing unit which are sequentially connected, wherein the water washing unit is connected with an external water supply system; The secondary heat kiln system comprises a primary kiln, a secondary kiln and a cooling kiln which are connected in series step by step, wherein the primary kiln comprises a pyrolysis chamber and a combustion chamber, a material outlet of the pyrolysis chamber is connected with a feed inlet of the secondary kiln, the combustion chamber is used for heating a heat exchange area, the combustion chamber is connected with external natural gas and combustion-supporting gas, the tail part of the combustion chamber is connected with an exhaust pipe, the hot air system comprises a rotary kiln hot blast stove, an outlet of the rotary kiln hot blast stove is connected with a material outlet side sealing cover of the secondary kiln, a smoke outlet is arranged at a feed end of the primary kiln, and the smoke outlet is connected with a smoke treatment system.
2. The solid waste salt disposal system of claim 1, wherein the pyrolysis system comprises a high-level bin connected with a feed inlet of a primary kiln through a feed screw conveyor, a discharge outlet of the primary kiln is connected with a feed inlet of a secondary kiln, a discharge outlet of the secondary kiln is connected with a feed inlet of a cooling kiln, and a discharge outlet of the cooling kiln is connected with the salt dissolving system through a discharge screw conveyor; The air outlet of the rotary kiln hot blast stove is connected with a discharge port side sealing cover of the two-stage kiln, the feed end of the first-stage kiln is provided with a flue gas outlet, and the flue gas outlet is connected with the flue gas treatment system; the outside of the combustion chamber of the primary kiln is provided with a hearth flue gas outlet which is connected with an exhaust funnel.
3. The solid waste salt disposal system according to claim 2, wherein a flue is arranged between the kiln head of the second-stage kiln and the kiln tail of the first-stage kiln, a cyclone dust collector is arranged at the flue gas outlet of the kiln head of the first-stage kiln, the exhaust port of the cyclone dust collector is connected with the flue gas treatment system, and the solid discharge port of the cyclone dust collector is connected with a ton bag for collecting solid particles.
4. A solid waste salt disposal system according to claim 3, wherein a hot air heat exchanger is arranged between the hearth flue gas outlet of the primary kiln and the exhaust pipe, and the hot air heat exchanger is communicated with an external combustion-supporting air pipeline which is connected with a combustion-supporting port of the combustion chamber of the primary kiln.
5. The solid waste salt disposal system of claim 1, wherein the flue gas treatment system comprises a secondary combustion chamber, a flue gas outlet of the secondary combustion chamber is connected with an inlet of a waste heat boiler, a material outlet of the secondary combustion chamber is connected with a ash collecting system, a urea spraying system is introduced into the waste heat boiler, a flue gas outlet of the waste heat boiler is connected with a quenching tower, a flue gas outlet of the quenching tower is connected with a bag-type dust collector, the quenching tower is connected with an active carbon spraying system and a baking soda spraying system, and a flue gas outlet of the bag-type dust collector is connected with a water washing unit.
6. The solid waste salt disposal system according to claim 5, wherein the water washing unit comprises a graphite cooling composite tower connected with a flue gas outlet of the bag-type dust collector, an air outlet end of the graphite cooling composite tower is connected with an inlet of the water washing tower, an outlet of the water washing tower is connected with an alkaline washing device, an air outlet end of the alkaline washing device is connected with a chimney, the alkaline washing device comprises a primary alkaline washing tower, a secondary alkaline washing tower and an alkaline liquid tank connected with the primary alkaline washing tower, an air outlet end of the water washing tower is connected with an air inlet end of the primary alkaline washing tower, an air outlet end of the primary alkaline washing tower is connected with an air inlet end of the secondary alkaline washing tower, an air outlet of the graphite cooling composite tower is connected with the waste acid recovery unit, an air outlet end of the secondary alkaline washing tower is connected with the chimney, and an air outlet of the secondary alkaline washing tower is connected with an air inlet of the primary alkaline washing tower.
7. The solid waste salt disposal system of claim 6, wherein the liquid outlet of the water scrubber is connected with the liquid inlet of the graphite cooling composite tower, the liquid outlet of the graphite cooling composite tower is connected with the waste acid recovery unit, the liquid outlets of the graphite cooling composite tower, the primary alkaline scrubber and the secondary alkaline scrubber are all provided with self-circulation pumps, and the liquid inlets are connected with the inside sprayer: The alkali liquor tank and the water supply system are respectively connected with a graphite cooling composite tower, a water washing tank, a primary alkaline washing tower and a secondary alkaline washing tower.
8. The solid waste salt disposal system of claim 7, wherein the one-stage kiln comprises roller bracket components, the front and rear of the roller bracket components respectively support the kiln inner cylinder component through the roller components and drive the kiln inner cylinder component to rotate through a rotary driving component, a kiln outer cylinder component is arranged outside the middle section of the kiln inner cylinder component, an air outlet is arranged at the top of the kiln outer cylinder component, a combustion chamber is formed between the kiln inner cylinder component and the outer cylinder component, a pyrolysis chamber is arranged inside the kiln inner cylinder component, a plurality of weir plates are arranged in the combustion chamber to divide the combustion chamber into a plurality of cavities, and annular uniformly distributed combustion nozzles are arranged outside each cavity and are communicated with an external air supply port; The kiln inner barrel assembly is internally provided with a material turning plate which is annularly and uniformly distributed along the interior of the kiln inner barrel assembly, the material turning plate is L-shaped, the open surface of the material turning plate faces the rotation direction of the kiln, the kiln inner barrel assembly is internally provided with a kiln head impeller, and the tail end of the kiln head impeller is provided with a material dredging assembly; The kiln head impeller comprises a fixed ring fixed on the inner wall of the kiln inner barrel assembly, a plurality of bent pipes which are arranged in a crossing mode are arranged in the fixed ring, steel balls are arranged in the bent pipes, the bent pipes comprise bending parts and straight line parts, and the bending parts are close to and connected with the fixed ring.
9. A method of disposal of solid waste salts, applied to the system of any one of claims 1 to 8, characterized in that the method comprises the steps of: Waste salt first-stage pyrolysis, namely pre-drying the waste salt, conveying the waste salt into a high-level bin, conveying the waste salt into a first-stage kiln through a feeding screw conveyor at the bottom of the high-level bin, wherein the front 6m of the first-stage kiln is a composite plate of carbon steel and hastelloy, the temperature is controlled below 350 ℃, the rear 12m is 310s, the temperature is controlled at 550 ℃, blanking the waste salt from the tail of the first-stage kiln into a second-stage kiln, and the discharging temperature of the first-stage kiln is about 550 ℃; The method comprises the steps of performing secondary pyrolysis on waste salt, namely heating for one hour after entering a secondary kiln, raising the temperature from 550 ℃ to 650 ℃, finally, blanking, entering a cooling kiln for cooling, cooling materials from 650 ℃ to 80 ℃ in the cooling kiln in a water cooling mode, finally, entering an assay tank of a salt dissolving system through spiral discharging from the cooling kiln, starting a rotary kiln hot blast furnace to generate 700 ℃ hot air, entering the kiln from the tail end of the secondary kiln, fully exchanging heat with the materials, and discharging air from the feed end of the secondary kiln to enter the tail section of the primary kiln; The flue gas is calcined and purified, namely, the flue gas enters a secondary combustion chamber for further combustion, the temperature of the flue gas reaches more than 1100 ℃, the temperature of the waste heat is recovered through a waste heat boiler and is reduced to about 550 ℃, the waste heat boiler is provided with an SNCR denitration device, urea can be added into the waste heat boiler for denitration, the temperature of the flue gas at an outlet of the waste heat boiler is reduced to below 200 ℃ through a quenching tower, residual dioxin, sulfur dioxide and other harmful components are further removed through spraying active carbon and baking soda into a pipeline, reacted particles are captured through a bag dust collector, the flue gas enters a spraying system, the top of the secondary combustion chamber is provided with an emergency discharge port, and the bottom of the secondary combustion chamber is provided with a slag discharge port. The steam generated by the waste heat boiler is sent to a salt dissolving and separating system after passing through a separating cylinder; And (3) discharging the gas after dedusting by the bag-type dust remover, wherein the gas enters a graphite cooling composite tower, the temperature of the gas is reduced to 80 ℃, acid gas in the gas is absorbed, the gas enters a water washing tower, the residual acid gas in the gas is further absorbed, spray water in the graphite cooling composite tower is fully contacted with the gas, most of the acid gas in the gas is absorbed, when the concentration of waste acid in spray liquid reaches a certain value, the waste acid is pumped to a waste acid tank, and finally the waste acid tank is sent out of the system, then the gas enters a two-stage alkaline washing tower, liquid alkali is added into the two-stage alkaline washing tower, the acid gas in the gas is thoroughly removed, and finally the waste acid gas is led to a chimney through a fan for emptying.
10. The solid waste salt disposal system of claim 9, wherein the combustion chamber of the primary kiln is heated by natural gas to generate furnace flue gas, the temperature of the flue gas is 400-500 ℃, the flue gas is cooled by a primary kiln hot air heat exchanger and is led to an exhaust drum for evacuation, the combustion-supporting air of the primary kiln enters a burner for supporting combustion after being preheated, and the hot blast stove directly uses normal-temperature air for supporting combustion.

Description

Solid waste salt disposal system and method Technical Field The embodiment of the disclosure relates to the technical field of waste salt recovery treatment, in particular to a solid waste salt disposal system and a method. Background The disclosure of this background section is only intended to increase the understanding of the general background of the disclosure and is not necessarily to be construed as an admission or any form of suggestion that this information forms the relevant art already known to those of ordinary skill in the art. The source of waste salt relates to wide industry, the characteristic pollutant is complex, the toxic property is undefined, and according to the 'solid waste control method', the waste salt is classified into dangerous waste which must be specially treated. The important industry sources are fields of pesticides, medicines, coal chemical industry, printing and dyeing, fly ash soda ash, new metallurgical materials and the like. The industrial waste salt contains toxic organic and inorganic impurities and the like and has a certain danger, so that the industrial waste salt cannot be directly applied to other industries, such as food, medicine and the like. At present, the main treatment method for the industrial waste salt is to pile or landfill the industrial waste salt, and the defects of space and field waste, land utilization rate reduction and the like exist. Especially when salt and impurities thereof are lost, serious damages such as land salinization, environmental pollution and the like can be caused. Therefore, harmless treatment and resource utilization are future outlets of industrial waste salt in China. The key point of harmless and recycling of the waste salt is to remove toxic organic and inorganic impurities in the waste salt. The harmless method is to remove organic and inorganic impurities in the waste salt, and then obtain the byproduct salt by membrane method, freezing, evaporating crystallization and other techniques. Disclosure of Invention Therefore, the embodiment of the disclosure provides a solid waste salt disposal system and a method thereof, so as to solve the problems of resource waste and environmental pollution caused by directly stacking and burying waste salt in the prior art. In order to achieve the above object, embodiments of the present disclosure provide the following technical solutions: in a first aspect of embodiments of the present disclosure, there is provided a solid waste salt disposal system comprising The pyrolysis system comprises a secondary thermal kiln system, a cooling kiln and a hot air system which are connected in series step by step, waste salt is pyrolyzed by step heating and pyrolyzing and then cooling, the hot air system is reversely introduced into a secondary kiln of the secondary thermal kiln system, pyrolysis smoke is formed by passing through a primary kiln, the pyrolysis smoke enters a smoke treatment system, and materials of the secondary thermal kiln system enter an assay tank of a salt dissolving and separating system through spiral discharging; the flue gas treatment system comprises a secondary combustion chamber, a waste heat boiler, a quenching tower, a bag-type dust remover, a waste acid recovery unit and a water washing unit which are sequentially connected, wherein the water washing unit is connected with an external water supply system; the secondary heat kiln system comprises a primary kiln and a secondary kiln which are serially connected step by step, wherein the primary kiln comprises a pyrolysis chamber and a combustion chamber, a material outlet of the pyrolysis chamber is connected with a feed inlet of the secondary kiln, the combustion chamber is used for heating in a heat exchange area, the combustion chamber is connected with external natural gas and combustion-supporting gas, the tail part of the combustion chamber is connected with an exhaust funnel, the hot air system comprises a rotary kiln hot blast stove, an outlet of the rotary kiln hot blast stove is connected with a material outlet side sealing cover of the secondary kiln, a flue gas outlet is arranged at a feed end of the primary kiln, and the flue gas outlet is connected with a flue gas treatment system. Further, the pyrolysis system comprises a high-level bin, the high-level bin is connected with a feed inlet of a first-stage kiln through a feed screw conveyor, a discharge outlet of the first-stage kiln is connected with a feed inlet of a second-stage kiln, a discharge outlet of the second-stage kiln is connected with a feed inlet of a cooling kiln, and a discharge outlet of the cooling kiln is connected with the salt dissolving system through a discharge screw conveyor; The air outlet of the rotary kiln hot blast stove is connected with a discharge port side sealing cover of the two-stage kiln, the feed end of the first-stage kiln is provided with a flue gas outlet, and the flue gas outlet is connected with the flue gas tr