A method for resource utilization of desulfurization waste liquid
By implementing multi-stage treatment and resource utilization of desulfurization wastewater, the pollution problem of desulfurization wastewater has been solved, and efficient resource recovery and production of high-value products have been achieved, resulting in a dual improvement in environmental and economic benefits.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUNAN RONGZHONG TECH DEV CO LTD
- Filing Date
- 2026-04-20
- Publication Date
- 2026-07-14
AI Technical Summary
Direct discharge of desulfurization wastewater leads to water and soil pollution, and sulfur and ammonia resources are not effectively utilized, resulting in resource waste.
Through two-stage processing of filtration and separation equipment, dilute sulfur foam liquid is separated into high-purity liquid sulfur and separation clear liquid. Dissolved salts and ammonia nitrogen pollutants are treated by evaporation and concentration equipment, and non-condensable gas is transported to the coking gas negative pressure pipeline for recycling. After the liquid sulfur and concentrated salt solution are used in the solidification equipment to prepare salt-containing crude sulfur, it is sent to the incinerator to produce high-value products.
It has achieved the clean and efficient utilization of desulfurization wastewater, reduced the risk of water and soil pollution, recovered ammonia resources, and produced high-value sulfur, sulfuric acid and liquid sulfur trioxide products, thus achieving a dual improvement in environmental and economic benefits.
Smart Images
Figure CN122380401A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical waste treatment technology, and in particular to a method for the resource utilization of desulfurization wastewater. Background Technology
[0002] Hydrogen sulfide-containing gases such as coke oven gas, blast furnace gas, and water gas are usually desulfurized and purified using wet oxidation methods such as HPF, PDS, or complexed iron. During the desulfurization process, a large amount of desulfurization waste liquid is generated. This waste liquid mainly exists in the form of dilute sulfur foam liquid. If it is directly discharged, it will cause serious water and soil pollution. Moreover, the sulfur, ammonia, and other resources in the waste liquid are not effectively utilized, resulting in resource waste. Summary of the Invention
[0003] The purpose of this invention is to provide a method for the resource utilization of desulfurization wastewater, so as to solve the problems existing in the prior art and realize the clean and efficient resource utilization of desulfurization wastewater.
[0004] To achieve the above objectives, the present invention provides the following solution: This invention provides a method for the resource utilization of desulfurization wastewater, comprising the following steps: S1, the dilute sulfur foam liquid produced by the desulfurization system is filtered to obtain concentrated sulfur foam liquid and filtered clear liquid; S2, the obtained concentrated sulfur foam liquid is separated by a separation device to obtain liquid sulfur and clear separation liquid; S3, the separated clear liquid is processed by an evaporation and concentration device to obtain a concentrated salt solution, and the non-condensable gas generated by the evaporation and concentration device is transported to the coking gas negative pressure pipeline. S4, the liquid sulfur and a portion of the concentrated salt solution are passed into a solidification device to obtain salt-containing crude sulfur; S5, the salt-containing crude sulfur and part of the concentrated salt solution are passed into an incinerator to obtain sulfur dioxide-containing flue gas, which is used to produce concentrated sulfuric acid or liquid sulfur trioxide.
[0005] Preferably, the secondary condensate generated by the evaporation and concentration equipment is used to be transported back to the desulfurization system and / or to the ammonia water system of the cooling drum section.
[0006] Preferably, the filtered liquid is returned to the desulfurization system via a return pipe.
[0007] Preferably, the return pipe of the filtered liquid is connected to a branch pipe, and the end of the branch pipe is used to enter the evaporation and concentration equipment.
[0008] Preferably, the elemental sulfur particles in the dilute sulfur foam solution account for less than 10% of the mass fraction of the dilute sulfur foam solution.
[0009] Preferably, the liquid sulfur produced by the separation equipment enters the curing equipment at a temperature of 120°C to 150°C.
[0010] Preferably, the concentrated salt solution produced by the evaporation and concentration equipment at a temperature of 50°C to 90°C and a concentration of 50% to 90% is introduced into the solidification equipment, and the remaining concentrated salt solution is introduced into the incinerator.
[0011] Preferably, the filtration device filters and enriches the elemental sulfur particles in the dilute sulfur foam liquid through physical filtration.
[0012] Preferably, the evaporation and concentration equipment obtains the concentrated salt solution through negative pressure low-temperature evaporation.
[0013] Preferably, the incinerator is equipped with a spray gun, through which the concentrated brine is fed into the incinerator.
[0014] The present invention achieves the following technical effects compared to the prior art: The resource utilization method for desulfurization wastewater provided by this invention utilizes a two-stage treatment process involving filtration and separation equipment to efficiently separate dilute sulfur foam liquid, which is difficult to utilize directly, into high-purity liquid sulfur and a clear separation liquid, achieving initial recovery of sulfur resources and reduction of wastewater volume. Secondly, for soluble salts and ammonia nitrogen pollutants in the wastewater, the clear liquid is further treated using evaporation and concentration equipment to obtain a concentrated brine solution, reducing the risk of water and soil pollution caused by direct discharge of wastewater. More importantly, the non-condensable gas generated by evaporation (rich in ammonia resources) is directly transported to a coking gas negative pressure pipeline for recycling, turning waste into… The process involves several steps: first, addressing the issue of ammonia resource loss; second, utilizing the recovered high-temperature liquid sulfur as a heat source and solidifying agent, mixing it with the generated concentrated salt solution in a solidification device to prepare salt-containing crude sulfur, which is then sent to an incinerator along with the remaining concentrated salt solution. This process achieves both the harmless treatment of difficult-to-treat salts in the waste liquid and the final conversion of sulfur into sulfur dioxide-containing flue gas for the production of high-value concentrated sulfuric acid or liquid sulfur trioxide. In this way, the originally severely polluting desulfurization waste liquid is completely converted into high-value chemical products such as sulfur, sulfuric acid / liquid sulfur trioxide, and recovered ammonia, achieving a dual improvement in environmental and economic benefits. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 A process flow diagram of the desulfurization waste liquid resource utilization method provided by the present invention. Detailed Implementation
[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0018] The purpose of this invention is to provide a method for the resource utilization of desulfurization wastewater, so as to solve the problems existing in the prior art and realize the clean and efficient resource utilization of desulfurization wastewater.
[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0020] Example 1 This embodiment provides a method for the resource utilization of desulfurization wastewater, such as... Figure 1 As shown, it includes the following steps: S1, the dilute sulfur foam liquid produced by the desulfurization system is filtered to obtain concentrated sulfur foam liquid and filtered clear liquid; S2, the obtained concentrated sulfur foam liquid is separated into liquid sulfur and clear liquid by a separation device; S3, the separated clear liquid is processed by an evaporation and concentration device to obtain concentrated brine, and the non-condensable gas generated by the evaporation and concentration device is transported to the coking gas negative pressure pipeline; S4, liquid sulfur and some concentrated salt solution are passed into a solidification device to obtain salt-containing crude sulfur; S5, salt-containing crude sulfur and some concentrated salt solution are passed into an incinerator to obtain sulfur dioxide-containing flue gas, which is used to produce concentrated sulfuric acid or liquid sulfur trioxide.
[0021] Through a two-stage treatment process involving filtration and separation equipment, the difficult-to-use dilute sulfur foam liquid is efficiently separated into high-purity liquid sulfur and a clear separation liquid, achieving initial recovery of sulfur resources and reduction of waste liquid volume. Secondly, for soluble salts and ammonia nitrogen pollutants in the waste liquid, the clear liquid is further treated using evaporation and concentration equipment to obtain a concentrated brine solution, reducing the risk of water and soil pollution caused by direct discharge of waste liquid. More importantly, the non-condensable gas generated by evaporation (rich in ammonia resources) is directly transported to the coking gas negative pressure pipeline for recycling, turning waste into treasure and solving the problem of ammonia resource loss. Finally, the recovered high-temperature liquid sulfur is used as a heat source and solidifying agent, and mixed with the generated concentrated salt solution in a solidification device to prepare salt-containing crude sulfur. This crude sulfur, along with the remaining concentrated salt solution, is then sent to an incinerator. This process not only achieves the harmless treatment of the difficult-to-treat salts in the waste liquid, but also ultimately converts the sulfur element into sulfur dioxide-containing flue gas for the production of high-value concentrated sulfuric acid or liquid sulfur trioxide. In this way, the originally seriously polluting desulfurization waste liquid is completely converted into high-value chemical products such as sulfur, sulfuric acid / liquid sulfur trioxide, and recovered ammonia, achieving a dual improvement in environmental and economic benefits.
[0022] The following are the setup instructions for the filtration equipment: Specifically, gases containing hydrogen sulfide, such as coke oven gas and blast furnace gas, are purified using wet oxidation desulfurization processes such as HPF or complexed iron. This desulfurization process requires the discharge of desulfurization waste liquid to maintain desulfurization efficiency. This desulfurization waste liquid is discharged from the desulfurization system in the form of dilute sulfur foam liquid.
[0023] In the optional solutions of this embodiment, it is more preferred that the elemental sulfur particles in the dilute sulfur foam liquid account for less than 10% of the mass fraction of the dilute sulfur foam liquid.
[0024] Specifically, the main components of dilute sulfur foam liquid are elemental sulfur particles and desulfurized clear liquid, with elemental sulfur particles typically accounting for less than 10% of the mass fraction of dilute sulfur foam liquid.
[0025] In the optional solutions of this embodiment, it is more preferred that the filtration device filters and enriches the elemental sulfur particles in the dilute sulfur foam liquid through physical filtration.
[0026] Specifically, the dilute sulfur foam liquid is processed by a filtration device to obtain concentrated sulfur foam liquid (containing 10-30% elemental sulfur) and filtered clear liquid (the desulfurized liquid). This filtration device mainly uses physical action to filter and enrich the elemental sulfur particles in the dilute sulfur foam liquid. The equipment type includes microporous filters, centrifuges, plate and frame filter presses, and filter bag filters.
[0027] Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 1 As shown, the filtered liquid is returned to the desulfurization system via a return pipe.
[0028] Specifically, the filtered liquid from the filtration equipment is returned to the desulfurization system; the concentrated sulfur foam liquid enters the subsequent separation equipment.
[0029] The following are the relevant setup instructions for the separation equipment: Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 1 As shown, a branch pipe is connected to the return pipe of the filtered liquid, and the end of the branch pipe is used to enter the evaporation and concentration equipment.
[0030] In the optional schemes of this embodiment, it is more preferred that the liquid sulfur produced by the separation equipment enters the curing equipment at a temperature of 120°C to 150°C.
[0031] Specifically, the concentrated sulfur foam liquid is processed by a separation device to obtain a separated clear liquid and liquid sulfur. This separation device mainly uses an external heat source to heat the concentrated sulfur foam liquid, causing the elemental sulfur particles to transform into a molten state, thereby separating them from the clear liquid. The separation device type can be one of a two-phase separator, a multiphase separator, or a sulfur melting kettle.
[0032] The following are the relevant settings instructions for the curing equipment: Specifically, liquid sulfur and concentrated salt solution are fed together into a solidification device to obtain salt-containing crude sulfur powder (blocks), which are then sent to a subsequent incinerator for pyrolysis. The main function of this solidification device is to mix and dry the two components to produce salt-containing crude sulfur. The device type is one of the following: paddle or disc dryer, spiral dryer, rotary drum slicer, or disc scraper.
[0033] The following are the relevant setup instructions for the evaporation and concentration equipment: Specifically, the evaporation and concentration equipment should be fed with the separated clear liquid first.
[0034] In the optional solutions of this embodiment, the more preferred method is to obtain concentrated brine through negative pressure low-temperature evaporation.
[0035] Among the optional solutions in this embodiment, the more preferred one is as follows: Figure 1 As shown, the secondary condensate produced by the evaporation and concentration equipment is used to be transported back to the desulfurization system and / or to the ammonia water system of the cooling drum section.
[0036] In the optional schemes of this embodiment, it is more preferred that the concentrated salt solution produced by the evaporation and concentration equipment at a temperature of 50°C to 90°C and a concentration of 50% to 90% is introduced into the solidification equipment, and the remaining concentrated salt solution is used to be introduced into the incinerator.
[0037] Specifically, the clarified liquid separated by the separation equipment is processed by an evaporation and concentration device to obtain a concentrated brine solution. This evaporation and concentration device adopts a negative pressure low-temperature evaporation process, and the equipment type is one of the following: single-effect evaporator, multi-effect evaporator, concentration tower, evaporation kettle, negative pressure low-temperature scraper conveyor, etc.
[0038] Specifically, the non-condensable gas (mainly ammonia) generated by the evaporation and concentration equipment is sent to the coking gas negative pressure pipeline to make full use of ammonia resources; the secondary condensate (i.e., secondary condensate) generated can be sent back to the desulfurization system or to the ammonia water system of the cooling drum section.
[0039] The following information pertains to the incinerator: In the optional schemes of this embodiment, it is more preferred that the incinerator is equipped with a spray gun, and the concentrated brine is sent into the incinerator through the spray gun.
[0040] Specifically, crude sulfur containing salt is pyrolyzed at high temperature in an incinerator to produce high-temperature flue gas containing sulfur dioxide, which is then used to produce concentrated sulfuric acid or liquid sulfur trioxide.
[0041] Specifically, while incinerating and pyrolyzing the crude sulfur containing salt, the concentrated salt solution is also incinerated to obtain high-temperature flue gas containing sulfur dioxide.
[0042] Regarding other related settings: Specifically, the filtered liquid produced by the filtration equipment and the separated liquid produced by the separation equipment are interconnected (i.e., the filtered liquid can also be fed into the evaporation and concentration equipment together with the separated liquid through branch pipes), which facilitates production operations.
[0043] Specifically, the main features of the resource utilization method for desulfurization wastewater provided in this embodiment are as follows: 1. No secondary solid waste is generated during the treatment process; 2. The desulfurization waste liquid treatment operation is highly flexible, effectively solving the problem of excessive waste liquid that cannot be treated; 3. The secondary condensate (composed of dilute ammonia water) produced by the evaporation and concentration equipment can be sent to the ammonia water system of the coking cold drum section, effectively solving the problem of liquid expansion in the desulfurization system; 4. The non-condensable gas (mainly ammonia) generated by the evaporation and concentration equipment is sent to the coking gas negative pressure pipeline to make full use of ammonia resources.
[0044] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.
Claims
1. A method for the resource utilization of desulfurization wastewater, characterized in that: Includes the following steps: S1, the dilute sulfur foam liquid produced by the desulfurization system is filtered to obtain concentrated sulfur foam liquid and filtered clear liquid; S2, the obtained concentrated sulfur foam liquid is separated by a separation device to obtain liquid sulfur and clear separation liquid; S3, the separated clear liquid is processed by an evaporation and concentration device to obtain a concentrated salt solution, and the non-condensable gas generated by the evaporation and concentration device is transported to the coking gas negative pressure pipeline. S4, the liquid sulfur and a portion of the concentrated salt solution are passed into a solidification device to obtain salt-containing crude sulfur; S5, the salt-containing crude sulfur and part of the concentrated salt solution are introduced into an incinerator to obtain sulfur dioxide-containing flue gas, which is used to produce concentrated sulfuric acid or liquid sulfur trioxide.
2. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The secondary condensate produced by the evaporation and concentration equipment is used to transport back to the desulfurization system and / or to the ammonia water system of the cooling drum section.
3. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The filtered liquid is returned to the desulfurization system via a return pipeline.
4. The method for resource utilization of desulfurization wastewater according to claim 3, characterized in that: A branch pipe is connected to the reflux pipe of the filtered liquid, and the end of the branch pipe is used to enter the evaporation and concentration equipment.
5. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The elemental sulfur particles in the dilute sulfur foam solution account for less than 10% of the mass fraction of the dilute sulfur foam solution.
6. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The liquid sulfur produced by the separation equipment enters the curing equipment at a temperature of 120°C to 150°C.
7. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The concentrated salt solution produced by the evaporation and concentration equipment at a temperature of 50℃~90℃ and a concentration of 50%~90% is fed into the solidification equipment, and the remaining concentrated salt solution is fed into the incinerator.
8. The method for resource utilization of desulfurization wastewater according to claim 5, characterized in that: The filtration device filters and enriches the elemental sulfur particles in the dilute sulfur foam liquid through physical filtration.
9. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The evaporation and concentration equipment obtains the concentrated salt solution through negative pressure and low temperature evaporation.
10. The method for resource utilization of desulfurization wastewater according to claim 1, characterized in that: The incinerator is equipped with a spray gun, through which the concentrated brine is fed into the incinerator.