Directional conversion and recovery system for carnallite generated by incineration of sulfur-containing three wastes

Abstract

The utility model discloses a system for directionally converting and recovering carnallite generated by burning sulfur-containing three wastes, which relates to the technical field of sulfur-containing three wastes treatment and comprises a slurry preparation system, a freezing crystallization system, a sodium sulfate crystallization and drying packaging system and a sodium sulfite crystallization and drying packaging system, according to the utility model, the incineration carnallite and water are proportionally prepared into slurry, then cooled to separate out salt, then centrifugally separated to obtain a sodium sulfate decahydrate wet material and a sodium sulfite mother solution, the sodium sulfate decahydrate wet material is re-dissolved and evaporated to separate out salt, crystal slurry is centrifugally dewatered to obtain a sodium sulfate wet material, and sodium sulfate crystal salt is obtained after drying. And finally, bagging and packaging for later use through a packaging machine. The sodium sulfite mother liquor is evaporated to separate out salt and centrifugally dewatered to obtain a wet sodium sulfite material, then the wet sodium sulfite material is dried to obtain sodium sulfite crystal salt, and finally the sodium sulfite crystal salt is bagged and packaged through a packaging machine for use. Therefore, the sodium sulfate and the sodium sulfite in the incineration carnallite are respectively extracted for resource utilization, and the pollution to the environment is reduced at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of sulfur-containing three wastes treatment, in particular to a system for directional conversion and recovery of miscellaneous salts generated by the incineration of sulfur-containing three wastes. Background Art

[0002] As environmental emission requirements become increasingly stringent, sodium desulfurization is used for the incineration of sulfur-containing waste to ensure that the concentrations of SO2 and SO3 emitted with the flue gas reach the lower limit of national and local environmental emission standards. The inorganic salts produced by flue gas desulfurization and the salt-containing wastewater produced by desulfurization waste liquid are mainly sodium sulfate and sodium sulfite, with sodium sulfite being the main component. If the incineration salts are not treated, it will have an impact on the surrounding environment and cause a waste of resources.

[0003] Many manufacturers produce salty wastewater from desulfurization waste liquid by aerating to convert sodium sulfite into sodium sulfate by contact with oxygen. The principle of this method is valid, but the conversion rate of sodium sulfite into sodium sulfate by contact with oxygen in actual operation is very low, and the equipment is large and the investment cost is high. The recovered inorganic salt is still a mixed salt of sodium sulfate and sodium sulfite.

[0004] Considering the difficulty of converting sodium sulfite into sodium sulfate, and the fact that sodium sulfite is more economical than sodium sulfate, the price of sodium sulfite on the market is much higher than that of sodium sulfate, and the usage is large, it is proposed to separate the mixed salt of sodium sulfate and sodium sulfite produced by flue gas desulfurization from the incineration of sulfur-containing organic waste, and the separated high-purity sodium sulfate and sodium sulfite can be used as chemical raw materials to realize resource utilization. Utility Model Content

[0005] The purpose of the utility model is to provide a directional conversion and recovery system for the miscellaneous salts generated by the incineration of sulfur-containing three wastes, so as to solve the problems proposed in the above background technology that the conversion rate of sodium sulfite into sodium sulfate in the actual operation process when it contacts with oxygen is very low, the equipment is bulky, the investment cost is large, and the recovered inorganic salts are still mixed salts of sodium sulfate and sodium sulfite.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a directional conversion and recovery system for impurities generated by the incineration of sulfur-containing three wastes, including a slurry preparation system and a freezing crystallization system connected to its rear end, the freezing crystallization system being respectively connected to a sodium sulfate crystallization and drying packaging system and a sodium sulfite crystallization and drying packaging system; the slurry preparation system includes a slurry preparation tank and its feeding port is connected to an incineration impurity feeding device through a pipeline, the slurry preparation tank is connected to a pure water pipe through a pipeline, and the slurry preparation tank is connected to a freezing crystallization system through a pipeline; the freezing crystallization system includes a cooling crystallizer connected to the slurry preparation tank, the cooling crystallizer is respectively connected to a cooling system and a slurry centrifuge through pipelines, and the solid material outlet of the slurry centrifuge is connected to the sodium sulfate crystallization and drying packaging system , the liquid material outlet is connected to a mother liquid tank through a pipeline, and the mother liquid tank is connected to a sodium sulfite crystallization and drying packaging system through a pipeline; the sodium sulfate crystallization and drying packaging system includes a recrystallizer connected to the slurry centrifuge, the recrystallizer is connected to a steam system through a pipeline, and the discharge port of the recrystallizer is sequentially connected to a sodium sulfate centrifuge, a sodium sulfate drying fluidized bed, a sodium sulfate silo, and an automatic sodium sulfate packaging machine through a pipeline; the sodium sulfite crystallization and drying packaging system includes an evaporative crystallizer connected to the mother liquid tank, the evaporative crystallizer is connected to the steam system through a pipeline, and the discharge port of the evaporative crystallizer is sequentially connected to a sodium sulfite centrifuge, a sodium sulfite drying fluidized bed, a sodium sulfite silo, and an automatic sodium sulfite packaging machine through a pipeline.

[0007] Preferably, the cooling crystallizer is a shell-and-tube heat exchanger, the water inlet and outlet of which are connected to a cooling system via pipelines, and the discharge port is connected to the slurry centrifuge via a pipeline.

[0008] Preferably, the discharge port temperature of the cooling crystallizer is -5°C to 5°C.

[0009] Preferably, the liquid outlet of the sodium sulfate centrifuge is connected to the slurry preparation tank through a pipeline.

[0010] Preferably, the steam outlet of the recrystallizer is connected to a condensate tank via a pipeline, and the outlet pipe of the condensate tank is connected to the pipeline between the sodium sulfate centrifuge and the slurry preparation tank; the steam outlet of the evaporative crystallizer is connected to the condensate tank via a pipeline.

[0011] Preferably, the pipeline between the sodium sulfate centrifuge and the slurry preparation tank is provided with a branch pipeline and connected to the recrystallizer.

[0012] Preferably, the liquid outlet of the sodium sulfite centrifuge is connected to the evaporation crystallizer and the slurry preparation tank respectively through pipelines.

[0013] Compared with the prior art, the beneficial effects of the utility model are:

[0014] The utility model prepares the incineration salt and water in proportion and sends them to a cooling crystallizer for cooling, and then centrifuges to obtain sodium sulfate decahydrate wet material and sodium sulfite mother liquor, the sodium sulfate decahydrate wet material is redissolved and evaporated for salt precipitation, the crystal slurry is centrifugally dehydrated to obtain sodium sulfate wet material, and then dried to obtain sodium sulfate crystal salt, and finally uses a packaging machine to bag and pack for use; the sodium sulfite mother liquor is evaporated for salt precipitation and centrifugally dehydrated to obtain sodium sulfite wet material, and then dried to obtain sodium sulfite crystal salt, and finally uses a packaging machine to bag and pack for use; thereby, sodium sulfate and sodium sulfite in the incineration salt are respectively extracted for resource utilization while reducing pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the process of the utility model;

[0016] In the figure: slurry preparation system-1, slurry preparation tank-11, incineration and miscellaneous salt feeding device-12, pure water pipe-13, freezing crystallization system-2, cooling crystallizer-21, cooling system-22, slurry centrifuge-23, mother liquor tank-24, sodium sulfate crystallization and drying packaging system-3, recrystallizer-31, steam system-32, sodium sulfate centrifuge-33, sodium sulfate drying fluidized bed-34, sodium sulfate silo-35, sodium sulfate automatic packaging machine-36, condensed water tank-37, sodium sulfite crystallization and drying packaging system-4, evaporation crystallizer-41, sodium sulfite centrifuge-42, sodium sulfite drying fluidized bed-43, sodium sulfite silo-44, sodium sulfite automatic packaging machine-45. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solution of the present utility model, the technical solution in the embodiments of the present utility model is clearly and completely described below in conjunction with the accompanying drawings and specific embodiments.

[0018] The utility model provides a directional conversion and recovery system for impure salts generated by the incineration of sulfur-containing three wastes, which is used for recovering inorganic salts generated by the incineration of sulfur-containing organic three wastes and sodium sulfate and sodium sulfite in salt-containing wastewater generated by desulfurization waste liquid; it comprises a slurry preparation system 1 and a freezing crystallization system 2 connected to its rear end, wherein the freezing crystallization system 2 is respectively connected to a sodium sulfate crystallization and drying packaging system 3 and a sodium sulfite crystallization and drying packaging system 4.

[0019] The slurry preparation system 1 is used to prepare incineration salt and pure water in proportion to obtain a salt solution, and to preheat the salt solution; it includes a slurry preparation tank 11, and the feeding port of the slurry preparation tank 11 is connected to an incineration salt feeding device 12 through a pipeline, which is used to quantitatively add incineration salt to the slurry preparation tank 11. At the same time, the slurry preparation tank 11 is also connected to a pure water pipe 13 through a pipeline, which is used to quantitatively add pure water to the slurry preparation tank 11, so that the incineration salt and pure water are mixed in proportion to obtain a salt solution; the salt solution in the slurry preparation tank 11 is transported to the freezing crystallization system 2 through a pipeline.

[0020] The freezing crystallization system 2 is used to obtain sodium sulfate decahydrate slurry by cooling the impure salt water solution obtained by the slurry preparation system 1, and to obtain sodium sulfate decahydrate wet material and frozen mother liquor by centrifugal dehydration of the sodium sulfate decahydrate slurry; it includes a cooling crystallizer 21 connected to the slurry preparation tank 11 through a pipeline, and the cooling crystallizer 21 is a shell and tube heat exchanger, the shell and tube inside of which is used for the circulation of the impure salt water solution, and the external heat exchange layer is connected to the cooling system 22 through a pipeline, which is used to quickly cool the impure salt water solution to between -5°C and 5°C, thereby precipitating a large amount of Sodium sulfate decahydrate is obtained and sodium sulfate decahydrate slurry is obtained. The slurry outlet of the cooling crystallizer 21 is connected to a slurry centrifuge 23 through a pipeline, which is used to centrifuge the sodium sulfate decahydrate slurry. After separation, solid sodium sulfate decahydrate wet material and frozen mother liquor are obtained respectively. The solid material outlet of the slurry centrifuge 23 is connected to a sodium sulfate crystallization and drying packaging system 3, and the liquid material outlet is connected to a mother liquor tank 24 through a pipeline, which is used to store the frozen mother liquor after centrifugal separation, and the mother liquor tank 24 is connected to a sodium sulfite crystallization and drying packaging system 4 through a pipeline.

[0021] The sodium sulfate crystallization and drying packaging system 3 is used to dissolve sodium sulfate decahydrate and evaporate and precipitate salt to obtain a crystalline solid phase, then obtain sodium sulfate crystal salt by centrifugal separation, and finally pack it in bags by a packaging machine; it includes a recrystallizer 31 connected to the slurry centrifuge 23, the recrystallizer 31 is connected to a steam system 32 through a pipeline for passing high-temperature steam into the recrystallizer 31 so that the sodium sulfate decahydrate wet material is redissolved by heating, and the redissolved solution is evaporated and salted by steam to obtain sodium sulfate slurry, the sodium sulfate slurry of the recrystallizer 31 is transported to the sodium sulfate centrifuge 33 through a pipeline for solid-liquid separation, and the separated liquid is transported to the slurry preparation tank 11 through a pipeline for re-slurry preparation operation, and after separation The sodium sulfate solid is transported to the sodium sulfate drying fluidized bed 34 for drying, and the dried sodium sulfate is transported to the sodium sulfate silo 35 for temporary storage, and the sodium sulfate temporarily stored in the sodium sulfate silo 35 is transported to the sodium sulfate automatic packaging machine 36 for bagging and packaging, so as to facilitate the resource utilization of sodium sulfate; the steam outlet of the recrystallizer 31 is connected to the condensate tank 37 through a pipeline, and the outlet pipe of the condensate tank 37 is connected to the pipeline between the sodium sulfate centrifuge 33 and the slurry preparation tank 11, which is used to transport the steam condensate to the slurry preparation tank 11 for slurry preparation operation; the pipeline between the sodium sulfate centrifuge 33 and the slurry preparation tank 11 is also provided with a branch pipeline and is connected to the recrystallizer 31, which is used to assist in re-dissolving the sodium sulfate decahydrate.

[0022] The sodium sulfite crystallization and drying packaging system 4 is used to evaporate and salt the frozen mother liquor, centrifugally dehydrate it to obtain a sodium sulfite wet material, and then dry the wet material to obtain sodium sulfite crystal salt and bag it; it includes an evaporation crystallizer 41 connected to the mother liquor tank 24, the evaporation crystallizer 41 is connected to the steam system 32 through a pipeline, and is used to pass steam into the evaporation crystallizer 41 to evaporate and dry the frozen mother liquor, and the dried steam is transported to the condensed water tank 37 through a pipeline, and the concentrated mother liquor in the evaporation crystallizer 41 after evaporation and salt precipitation is transported to the condensed water tank 37 through a pipeline. The sodium sulfite is transported to the sodium sulfite centrifuge 42 for centrifugal separation, a small part of the mother liquor after centrifugal separation is transported to the slurry preparation tank 11 through a pipeline for re-slurry preparation, most of the mother liquor after centrifugal separation is discharged, and the separated sodium sulfite solid is transported to the sodium sulfite drying fluidized bed 43 for drying, and the dried sodium sulfite solid is transported to the sodium sulfite silo 44 for temporary storage, and the sodium sulfite solid temporarily stored in the sodium sulfite silo 44 is transported to the sodium sulfite automatic packaging machine 45 for packaging and bagging, so as to facilitate the resource utilization of sodium sulfite.

[0023] The utility model prepares the incineration salt and water in proportion and sends them to a cooling crystallizer for cooling, and then centrifuges to obtain sodium sulfate decahydrate wet material and sodium sulfite mother liquor, the sodium sulfate decahydrate wet material is redissolved and evaporated for salt precipitation, the crystal slurry is centrifugally dehydrated to obtain sodium sulfate wet material, and then dried to obtain sodium sulfate crystal salt, and finally uses a packaging machine to bag and pack for use; the sodium sulfite mother liquor is evaporated for salt precipitation and centrifugally dehydrated to obtain sodium sulfite wet material, and then dried to obtain sodium sulfite crystal salt, and finally uses a packaging machine to bag and pack for use; thereby, sodium sulfate and sodium sulfite in the incineration salt are respectively extracted for resource utilization while reducing pollution to the environment.

[0024] Although the embodiments of the utility model have been shown and described, it is obvious that the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, it can be understood by ordinary technicians in this field that all other embodiments obtained by making various changes, modifications, substitutions and variations to these embodiments without departing from the principle and spirit of the utility model and without making creative work, all belong to the scope of protection of the utility model.

Claims

1. A directional conversion and recovery system for miscellaneous salts generated by the incineration of sulfur-containing waste, characterized in that: The invention comprises a slurry preparation system (1) and a freezing crystallization system (2) connected to its rear end, wherein the freezing crystallization system (2) is respectively connected to a sodium sulfate crystallization and drying packaging system (3) and a sodium sulfite crystallization and drying packaging system (4); the slurry preparation system (1) comprises a slurry preparation tank (11) and a feeding port thereof is connected to an incineration salt feeding device (12) via a pipeline, the slurry preparation tank (11) is connected to a pure water pipe (13) via a pipeline, and the slurry preparation tank (11) is connected to the freezing crystallization system (2) via a pipeline; the freezing crystallization system (2) comprises a cooling crystallizer (21) connected to the slurry preparation tank (11), the cooling crystallizer (21) is respectively connected to a cooling system (22) and a crystal slurry centrifuge (23) via pipelines, the solid material outlet of the crystal slurry centrifuge (23) is connected to the sodium sulfate crystallization and drying packaging system (3), and the liquid material outlet is connected to a mother liquid tank (24) via a pipeline, and the mother liquid tank (24) The sodium sulfate crystallization and drying packaging system (4) is connected to the sodium sulfite crystallization and drying packaging system (4) through a pipeline; the sodium sulfate crystallization and drying packaging system (3) comprises a recrystallizer (31) connected to the slurry centrifuge (23), the recrystallizer (31) is connected to a steam system (32) through a pipeline, and the discharge port of the recrystallizer (31) is connected to the sodium sulfate centrifuge (33), the sodium sulfate drying fluidized bed (34), the sodium sulfate silo (35), and the sodium sulfate automatic packaging machine (36) in sequence through a pipeline; the sodium sulfite crystallization and drying packaging system (4) comprises an evaporation crystallizer (41) connected to the mother liquid tank (24), the evaporation crystallizer (41) is connected to the steam system (32) through a pipeline, and the discharge port of the evaporation crystallizer (41) is connected to the sodium sulfite centrifuge (42), the sodium sulfite drying fluidized bed (43), the sodium sulfite silo (44), and the sodium sulfite automatic packaging machine (45) in sequence through a pipeline.

2. The directional conversion and recovery system for the miscellaneous salts generated by the incineration of sulfur-containing three wastes according to claim 1 is characterized in that: The cooling crystallizer (21) is a shell-and-tube heat exchanger, the water inlet and outlet of which are connected to a cooling system (22) via a pipeline, and the discharge port is connected to the slurry centrifuge (23) via a pipeline.

3. The directional conversion and recovery system for the miscellaneous salts generated by the incineration of sulfur-containing three wastes according to claim 2 is characterized in that: The outlet temperature of the cooling crystallizer (21) is -5°C to 5°C.

4. The system for directional conversion and recovery of impurity salts generated by incineration of sulfur-containing three wastes according to claim 3 is characterized in that: The liquid outlet of the sodium sulfate centrifuge (33) is connected to the slurry preparation tank (11) through a pipeline.

5. The system for directional conversion and recovery of impurity salts generated by incineration of sulfur-containing three wastes according to claim 4 is characterized in that: The steam outlet of the recrystallizer (31) is connected to a condensed water tank (37) via a pipeline, and the outlet pipe of the condensed water tank (37) is connected to the pipeline between the sodium sulfate centrifuge (33) and the slurry preparation tank (11); the steam outlet of the evaporative crystallizer (41) is connected to the condensed water tank (37) via a pipeline.

6. The system for directional conversion and recovery of impurity salts generated by incineration of sulfur-containing three wastes according to claim 5 is characterized in that: The pipeline between the sodium sulfate centrifuge (33) and the slurry preparation tank (11) is provided with a branch pipeline and is connected to the recrystallizer (31).

7. The system for directional conversion and recovery of impurity salts generated by incineration of sulfur-containing wastes according to claim 6 is characterized in that: The liquid outlet of the sodium sulfite centrifuge (42) is connected to the evaporation crystallizer (41) and the slurry preparation tank (11) through pipelines.

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