CN115180753A - Method and system for catalytic desalting of SRG washing wastewater - Google Patents

Method and system for catalytic desalting of SRG washing wastewater Download PDF

Info

Publication number
CN115180753A
CN115180753A CN202110359165.8A CN202110359165A CN115180753A CN 115180753 A CN115180753 A CN 115180753A CN 202110359165 A CN202110359165 A CN 202110359165A CN 115180753 A CN115180753 A CN 115180753A
Authority
CN
China
Prior art keywords
sulfur
srg
tank
activated carbon
liquid separation
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.)
Granted
Application number
CN202110359165.8A
Other languages
Chinese (zh)
Other versions
CN115180753B (en
Inventor
杨本涛
李小龙
康建刚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhongye Changtian International Engineering Co Ltd
Original Assignee
Zhongye Changtian International Engineering Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Zhongye Changtian International Engineering Co Ltd filed Critical Zhongye Changtian International Engineering Co Ltd
Priority to CN202110359165.8A priority Critical patent/CN115180753B/en
Publication of CN115180753A publication Critical patent/CN115180753A/en
Application granted granted Critical
Publication of CN115180753B publication Critical patent/CN115180753B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/02—Preparation of sulfur; Purification
    • C01B17/06—Preparation of sulfur; Purification from non-gaseous sulfides or materials containing such sulfides, e.g. ores
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/02—Treatment of water, waste water, or sewage by heating
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/70—Treatment of water, waste water, or sewage by reduction
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F2001/007—Processes including a sedimentation step
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/101—Sulfur compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/16—Nitrogen compounds, e.g. ammonia
    • C02F2101/18—Cyanides
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/18—Nature of the water, waste water, sewage or sludge to be treated from the purification of gaseous effluents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/06—Controlling or monitoring parameters in water treatment pH

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Hydrology & Water Resources (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Water Treatment By Sorption (AREA)
  • Catalysts (AREA)

Abstract

The invention discloses a method and a system for catalytic desalination of SRG washing wastewater. Active carbon powder contained in SRG washing wastewater is used as a carrier, acidolysis of thiosulfate ions contained in the SRG washing wastewater is used as a sulfur source, and settling adsorption is carried out at normal temperature and normal pressure to obtain the sulfur-containing active carbon. Then the sulfur-containing active carbon is used as a catalyst, the disproportionation reaction of high-concentration bisulfite ions can be realized at the temperature of about 50 ℃, and sulfur resources can be obtained by recovery. The invention can recover sulfur while treating the wastewater, realizes the resource treatment of the wastewater and generates no secondary pollution. Therefore, the sulfur-containing activated carbon is used as a catalyst for the disproportionation and desulfurization reaction of the sulfurous acid ions in the SRG washing wastewater, and has wide market prospect and economic benefit.

Description

Method and system for catalytic desalting of SRG washing wastewater
Technical Field
The invention relates to an SRG washing wastewater treatment technology, in particular to a method for catalytic desalination of SRG washing wastewater and a catalytic desalination system thereof, belonging to the technical field of SRG flue gas washing wastewater treatment and sulfur resource recovery.
Background
Sintering flue gas in the steel industry is subjected to a flue gas purification process by adopting an activated carbon method for desulfurization and denitrification, and sulfur dioxide gas collected by activated carbon is concentrated and released and then is sent to a sulfur resource workshop to produce sulfur resources. The flue gas enriched with sulfur dioxide gas is called sulfur-enriched gas (SRG flue gas) for short, and the gas can be processed by the procedures of purification, drying, conversion, absorption and the like to prepare sulfur resources meeting the national standard, and the resource recovery value is high. But the purification process in the process of producing sulfur resources can simultaneously wash impurities and harmful elements in the flue gas and enter the acidic washing wastewater, and meanwhile, part of sulfur dioxide gas in the flue gas can also be absorbed by water vapor and brought into the wastewater.
Generally, because the acidic substances are greater than the alkaline substances in the SRG gas, the SRG flue gas washing wastewater tends to be acidic. When cyanide and derivatives thereof exist in the front-end flue gas, the cyanide and the derivatives thereof enter the SRG gas and are finally dissolved in the acidic washing wastewater, so that the alkalinity of the wastewater is increased (for example, cyanic acid is hydrolyzed to generate ammonia nitrogen), and the acidic washing wastewater is neutral. The acidic washing wastewater is neutral, SO a large amount of SO in SRG gas can be caused 2 Acid gas is dissolved to cause the generation of nitrous oxide in the wastewaterThe hydrogen sulfate radical increases dramatically. The detection result shows that the concentration of the hydrogen sulfite in the acidic washing wastewater generated by the washing of the cyanide-free SRG gas is 2-5 g/L, and the concentration of the hydrogen sulfite in the acidic washing wastewater generated by the washing of the cyanide-containing SRG gas is 240-300 g/L. If the acidic washing wastewater containing bisulfite with high concentration enters a subsequent wastewater treatment system, the treatment difficulty is huge. On one hand, the alkali consumption is increased sharply, the waste of liquid alkali is caused, and the discharge amount of waste water is increased; in addition, during the process of adding alkali, sodium sulfite salt is formed and crystallized, and system blockage and paralysis are caused.
Sulfur is an oxygen group simple substance non-metallic solid, is an important chemical raw material, and is widely used for producing various chemical products, gunpowder, matches, pigments and medicinal products. Powdered sulfur is used agriculturally as an insecticide and fungicide. The sulfur is mainly derived from ore bed extraction of natural sulfur and recovery of sulfur from natural gas, coal gas and industrial waste gas. With the expansion of sulfur demand, the recovery of sulfur from waste gases or waste water is becoming an increasingly important source of sulfur.
The liquid phase disproportionation process for preparing sulfur is characterized by that it utilizes the characteristic of sulfur element in bisulfite as intermediate valence state, and makes it produce disproportionation under the condition of high temp. and catalyst so as to implement recovery of elemental sulfur. Aiming at the defect that the blockage is caused by the crystallization of a wastewater system caused by directly adding alkali due to the higher concentration of the bisulfite in the wastewater. The use of "acid stripping" and "precipitation" methods has been reported earlier, but these methods have more or less drawbacks. The method specifically comprises the following steps:
an acidification stripping method: the bisulfite is utilized to become sulfur dioxide to escape under the acidic condition, thereby realizing the reduction of the concentration of the bisulfite. The reactions involved are: HSO 3 - +H + →H 2 SO 3 ；H 2 SO 3 + air → H 2 O+SO 2 ×) @. However, this method requires the addition of an acid solution, which increases the total water content and increases the amount of acid solution added. In addition, the method utilizes strong acid to prepare weak acid, and the total salt content can be reduced by only 50% at most.
A precipitation method: by utilizing the property that the bisulfite forms sulfate with metal cations,the sulfate is removed, such as adding calcium oxide, magnesium oxide, ferrous sulfate, ferric chloride, ferrous chloride, ferric nitrate and ferrous nitrate. The reactions involved are: SO 3 2- + precipitant M → MSO 3 ↓. The process produces a large amount of solid slag and the metal salts are generally expensive.
A disproportionation method: such as Chinese patent documents 201210391355.9, 201210392392.1 and 201711078170.1. Based on the property that bisulphite can be disproportionated to elemental sulphur and sulphate, a 1/3 reduction in bisulphite without consuming added substances is achieved. The reaction involved is: 3HSO 3 - →S+2SO 4 2- +H + +H 2 And O. The temperature of the direct reaction is > 160 ℃. The reaction temperature can be reduced by adding the catalyst: if selenium is added, the reaction temperature can be reduced to 80-100 ℃; adding iodine and under the action of photocatalysis, the reaction can be carried out at normal temperature. But because selenium and iodine are expensive, the possibility of industrial application is not provided. Among the above methods, the disproportionation method has the advantages of no additional consumption of substances, no increase in water amount, and the like. Disproportionation of the bisulfite by catalytic methods for sulfur recovery is a low cost process of operation. However, the process has not been widely popularized due to the high price of the catalyst. Therefore, the method for recycling the SRG washing wastewater by using the low-cost and high-efficiency bisulfite disproportionation catalyst is of great significance.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for catalytic desalination of SRG washing wastewater and a catalytic desalination system thereof. Active carbon powder contained in SRG washing wastewater is used as a carrier, thiosulfate ions contained in the SRG washing wastewater are used as a sulfur source, and sedimentation adsorption is carried out at normal temperature and normal pressure to obtain the sulfur-containing active carbon. Then sulfur-containing activated carbon is used as a catalyst, and the disproportionation reaction of high-concentration hydrogen sulfite ions can be realized at a lower temperature (about 50 ℃) to recover and obtain sulfur resources. On one hand, the content of salt in the SRG washing wastewater is reduced, and on the other hand, the purpose of recycling sulfur is realized; the consumption of liquid caustic soda is greatly reduced, and the consumption of the liquid caustic soda can be reduced by about 60 percent through a comparison test. The sulfur-containing activated carbon used in the invention has the advantages of simple preparation process, easily obtained raw materials, low price and large-scale application prospect, and the prepared sulfur-containing activated carbon can be recycled. In addition, the invention can recover sulfur while treating the wastewater, thereby realizing the resource treatment of the wastewater and avoiding the generation of secondary pollution. Therefore, the sulfur-containing activated carbon is used as a catalyst for the disproportionation and desulfurization reaction of the sulfurous acid ions in the SRG washing wastewater, and has wide market prospect and economic benefit.
In order to achieve the above object, the technical solution adopted by the present invention is specifically as follows:
in accordance with a first embodiment of the present invention, a method for the catalytic desalination of SRG wash wastewater is provided.
A method for the catalytic desalination of SRG washing wastewater, which comprises the following steps:
1) And (3) separating activated carbon powder from the SRG washing wastewater, adding acid into part of the SRG washing wastewater for acidification, mixing the activated carbon powder and the acidified part of the SRG washing wastewater, and performing sedimentation adsorption. Finally, carrying out solid-liquid separation to obtain the sulfur-containing activated carbon and the desulfurization wastewater.
2) Uniformly mixing the desulfurization wastewater and the residual SRG washing wastewater, and then adding sulfur-containing activated carbon to perform catalytic disproportionation.
3) And continuously monitoring the pH value of the reaction system in the step 2) until the pH value is changed to a pH set value. Then carrying out solid-liquid separation to obtain filtrate.
4) And (4) continuously heating the filtrate obtained in the step 3) for reaction until precipitation is generated and a clear supernatant appears, and filtering to obtain sulfur and SRG washing wastewater after desalting.
Preferably, in step 1), the SRG washing wastewater is a cyanide-containing SRG washing wastewater.
Preferably, in step 1), the portion of the SRG wash wastewater is used in an amount such that the numerical ratio in the portion of the SRG wash wastewater is from 0.05 to 0.5, preferably from 0.1 to 0.3, more preferably from 0.15 to 0.25.
Preferably, in step 1), the acid is one or more of hydrochloric acid, sulfuric acid, nitric acid, nitrous acid and phosphoric acid. Preferably sulfuric acid.
Preferably, in step 2), the disproportionation reaction is carried out at a temperature of 40 to 80 ℃, preferably 45 to 70 ℃, more preferably 50 to 60 ℃. The disproportionation reaction time is 0.3-10h, preferably 0.5-8h, and more preferably 0.8-5h.
Preferably, in step 3), the pH set point is < 3, preferably the pH set point is < 2.5, more preferably the pH set point is < 2.
Preferably, in step 4), the reaction temperature of the heating reaction is 50 to 120 ℃, preferably 60 to 110 ℃, and more preferably 70 to 100 ℃.
Preferably, step 1) is specifically: the activated carbon powder in the SRG washing wastewater is separated for standby, then part of the SRG washing wastewater is taken, and acid (such as sulfuric acid) is added into the part of the SRG washing wastewater to adjust the pH value to be less than 3 (preferably the pH value to be less than 2). Then adding the activated carbon powder into the acidified SRG wastewater for sedimentation adsorption (the adsorption time is 0.3-5h, preferably 0.5-3 h). And after adsorption, carrying out solid-liquid separation to obtain solid and filtrate, and drying the obtained solid to obtain the sulfur-containing activated carbon.
Generally, the sulfur-containing activated carbon has a sulfur loading of 1.6 to 16g, preferably 3.2 to 9.6g, and more preferably 4.8 to 8g per gram of activated carbon.
Preferably, the sulfur-containing activated carbon is activated carbon after multiple times of sedimentation adsorption, preferably 2 to 10 times, and more preferably 3 to 5 times. The SRG washing wastewater used for each settling adsorption is derived from the original SRG washing wastewater.
Preferably, step 2) is specifically: uniformly mixing the filtrate obtained after the solid-liquid separation in the step 1) with the residual SRG washing wastewater. Then adding sulfur-containing activated carbon, heating to 40-80 deg.C (preferably 50-60 deg.C), and performing disproportionation reaction for 0.3-10h (preferably 0.5-8 h) to obtain disproportionation reaction system, and performing step 3).
Preferably, step 3) is specifically: continuously monitoring the pH value of the disproportionation reaction system in the step 2), and filtering when the pH value of the disproportionation reaction system is lower than 3 (preferably, the pH value is lower than 2), separating out sulfur-containing activated carbon and obtaining filtrate. Returning the sulfur-containing activated carbon to the step 2) to be continuously used as the catalyst, and performing the step 4) on the filtrate.
Preferably, the step 4) is specifically: heating the filtrate obtained in step 3) to 50-120 deg.C (preferably 70-100 deg.C) to react until sulfur precipitate and clear supernatant is obtained. Then separating out sulfur precipitate, drying to obtain elemental sulfur, and discharging the supernatant after the sulfur precipitate is separated out and treated by a wastewater post-treatment system.
According to a second embodiment of the present invention, a method for catalytic desalination of SRG washing wastewater is provided.
A system for the catalytic desalination of SRG washing wastewater or the SRG washing wastewater used in the method of the first embodiment comprises a wastewater conveying device, a carbon-liquid separation tank, a sedimentation adsorption tank, a catalytic disproportionation tank and a colloid destabilizing tank. And the wastewater conveying device is communicated with a feed inlet of the carbon-liquid separation tank. The carbon-liquid separation tank, the sedimentation adsorption tank, the catalytic disproportionation tank and the colloid destabilizing tank are sequentially connected in series.
Preferably, the system also comprises an acidification treatment tank which is positioned between the carbon liquid separation tank and the sedimentation adsorption tank. And the water outlet of the carbon-liquid separation tank is communicated with the water inlet of the acidification tank through a first pipeline. And the water outlet of the acidification treatment pool is communicated with the water inlet of the sedimentation adsorption pool through a second pipeline. An acid liquor conveying pipeline is connected to an acid inlet of the acidification tank.
Preferably, the system further comprises an activated carbon buffer bin. The active carbon buffer bin is positioned between the carbon-liquid separation tank and the sedimentation adsorption tank. And the discharge port of the carbon-liquid separation tank is communicated with the feed port of the activated carbon buffer bin through a first material conveying device. And the discharge port of the charcoal buffer bin is communicated with the feed inlet of the sedimentation adsorption tank through a second material conveying device.
Preferably, the system further comprises a liquid mixing tank. The liquid mixing tank is positioned between the sedimentation adsorption tank and the catalytic disproportionation tank. And the water outlet of the sedimentation adsorption tank is communicated with the water inlet of the liquid mixing tank through a third pipeline. The water outlet of the carbon-liquid separation tank is also communicated with the water inlet of the liquid mixing tank through a fourth pipeline. And the water outlet of the liquid mixing tank is communicated with the water inlet of the catalytic disproportionation tank through a fifth pipeline.
Preferably, the system further comprises a sulfur-containing activated carbon buffer bin. The sulfur-containing activated carbon buffer bin is positioned between the sedimentation adsorption tank and the catalytic disproportionation tank. And the discharge port of the sedimentation adsorption tank is communicated with the feed inlet of the sulfur-containing activated carbon buffer bin through a third material conveying device. And the discharge port of the sulfur-containing activated carbon buffer bin is communicated with the feed inlet of the catalytic disproportionation pool through a fourth material conveying device.
Preferably, the discharge port of the sulfur-containing activated carbon buffer bin is communicated with the feed inlet of the sedimentation adsorption tank through a fifth material conveying device.
Preferably, the system further comprises a first solid-liquid separation device. The first solid-liquid separation device is positioned between the catalytic disproportionation tank and the colloid destabilizing tank. And a discharge port of the catalytic disproportionation tank is connected with a feed inlet of the first solid-liquid separation device through a sixth material conveying device. And the water outlet of the first solid-liquid separation device is communicated with the water inlet of the colloid destabilizing tank through a sixth pipeline.
Preferably, the discharge port of the first solid-liquid separation device is also communicated with the feed port of the catalytic disproportionation pool through a seventh material conveying device.
Preferably, the system further comprises a second solid liquid separation device. And a feed inlet of the second solid-liquid separation device is communicated with a discharge outlet of the colloid destabilizing tank through an eighth material conveying device. And a discharge port of the second solid-liquid separation device is connected with a ninth material conveying device, and a water discharge port of the second solid-liquid separation device is connected with a seventh pipeline.
Preferably, the system further comprises a sulfur drying device. And a feed inlet of the sulfur drying device is communicated with a discharge outlet of the second solid-liquid separation device through a ninth material conveying device. And a protective gas conveying pipeline is connected to the gas inlet of the sulfur drying device.
Preferably, the system further comprises a waste water post-treatment system. And a water inlet of the wastewater post-treatment system is communicated with a water outlet of the second solid-liquid separation device through a seventh pipeline.
Preferably, the system also comprises a sulfur storage bin. The sulfur storage bin is communicated with a discharge port of the sulfur drying device through a tenth material conveying device.
In the prior art, because the acidic substances in the SRG gas are more than the alkaline substances, the SRG flue gas washing wastewater is always acidic. When cyanide and derivatives thereof exist in the front-end flue gas, the cyanide and the derivatives thereof enter the SRG gas and are finally dissolved in the acidic washing wastewater, so that the alkalinity of the wastewater is increased (for example, cyanic acid is hydrolyzed to generate ammonia nitrogen), and the acidic washing wastewater is neutral. The acidic washing wastewater is neutral, SO a large amount of SO in SRG gas can be caused 2 The acid gas dissolves, causing a sharp increase in the hydrogen sulfite in the wastewater. The detection result shows that the concentration of the hydrogen sulfite in the acid washing wastewater generated by the cyanide-free SRG gas washing is 2-5 g/L, and the concentration of the hydrogen sulfite in the acid washing wastewater generated by the cyanide-containing SRG gas washing is 240-300 g/L. If the acidic washing wastewater containing bisulfite with high concentration enters a subsequent wastewater treatment system, the treatment difficulty is huge. On one hand, the alkali consumption is increased sharply, the waste of liquid alkali is caused, and the discharge amount of waste water is increased; in addition, during the process of adding alkali, sodium sulfite salt is formed and crystallized, and system blockage and paralysis are caused. The existing acidification stripping method, precipitation method and disproportionation method have the problems of low treatment efficiency and high input cost, and are not beneficial to large-scale industrial popularization and application.
At present, the sulfur is mainly extracted from natural sulfur ore deposits and recovered from natural gas, coal gas and industrial waste gas. With the expansion of sulfur demand, the recovery of sulfur from waste gases or waste water is becoming an increasingly important source of sulfur. The liquid phase disproportionation for sulfur production is characterized in that the sulfur element in the bisulfite is in an intermediate valence state, and the disproportionation is carried out at a high temperature (for example, the temperature of the bisulfite directly undergoing disproportionation reaction is more than 160 ℃) and under the condition of a catalyst, so as to realize the recovery of elemental sulfur. However, the existing catalysts such as selenium and iodine are expensive, so that the catalyst is not suitable for industrial mass production and application at present.
In the present invention, the inventors of the present application have found, through studies, that the disproportionation of a high concentration of bisulfite can be achieved at a low temperature (around 50 ℃) when elemental sulfur and activated carbon coexist, with respect to the high bisulfite-containing property of cyanide-containing SRG wastewater. The sulfur-containing activated carbon is used as a catalyst, so that the disproportionation reaction of high-concentration hydrogen sulfite ions is realized, and the sulfur resource is obtained. On one hand, the salt content in the SRG washing wastewater is reduced, and on the other hand, the purpose of sulfur resource utilization is realized; the liquid caustic soda consumption in the subsequent wastewater treatment process is greatly reduced, and the liquid caustic soda consumption can be reduced by about 60% through a contrast test. The sulfur-containing activated carbon used in the invention has the advantages of simple preparation process, easily available raw materials, low price and large-scale application prospect, and the prepared sulfur-containing activated carbon can be recycled.
In the invention, under the catalytic action of sulfur-containing activated carbon, hydrogen ions and sulfite ions in the SRG washing wastewater undergo a catalytic disproportionation reaction. Namely, the bisulfite can generate disproportionation reaction under the catalysis of sulfur-containing activated carbon at the temperature of 40-80 ℃ (preferably 50-60 ℃) to disproportionate S (IV) into S (0) and S (VI). The solution pH will decrease throughout the reaction. When the pH value of the solution is reduced to be less than 3 (preferably to be less than 2), the catalyst is filtered and separated (the separated sulfur-containing catalyst can be recycled after being dried, so that the investment cost of the catalyst is greatly reduced). The remaining solution is a sulphur colloid and further heating (e.g. to 50-120 c, preferably to 70-100 c) is continued to destabilize the colloid and finally form sulphur particles. Separating out sulfur particle precipitate and drying to obtain the elemental sulfur. The invention can recover sulfur while reducing the salt content of the washing wastewater, realizes the resource utilization and treatment of the wastewater and does not generate secondary pollution. The disproportionation of S (IV) into S (0) and S (VI) proceeds as follows: carrying out catalytic disproportionation by taking sulfur-containing activated carbon as a catalyst:
Figure BDA0003004764230000061
generally, the sulfur-containing activated carbon is prepared by using high-quality activated carbon as base carbon through a special process, and is mainly used for mercury-containing gases such as natural gas/coal gas and the likeThe demercuration device is used for demercuration. In the invention, the sulfur-containing activated carbon is prepared by an adsorption method, which specifically comprises the following steps: because the SRG washing wastewater contains a large amount of thiosulfate, acidolysis can be carried out under an acidic condition to release colloidal sulfur, part of SRG wastewater containing thiosulfate ions is used as a sulfur source after being subjected to acidification treatment, and active carbon contained in the SRG washing wastewater is used as an adsorption carrier (or active carbon can be additionally added). Mixing activated carbon with the SRG washing wastewater containing thiosulfate ions after acid hydrolysis (generally, the total addition amount of thiosulfate ions is larger than that of activated carbon, for example, the numerical ratio of 0.05-0.5. Meanwhile, in the acidolysis process, because the solution is mixed with the activated carbon powder or the activated carbon particles, the colloidal sulfur separated out by the acidolysis of thiosulfate ions can be adsorbed into the activated carbon powder or the activated carbon particles through the adsorption effect (the sedimentation adsorption process) of the activated carbon powder or the activated carbon particles, so as to form the sulfur-containing activated carbon. The specific reaction formula is as follows: acid hydrolysis of thiosulfate ions under acidic conditions: s. the 2 O 3 2- +H + → S (Sulfur colloid) + HSO 3 - 。
In the present invention, the compounding process of the sulfur-containing activated carbon is as follows: s + AC → S @ AC. (AC means activated carbon). The sulfur-containing activated carbon has the advantages of simple preparation process, low price, wide source, easy separation and recovery and long service life.
In the invention, sulfur-containing activated carbon is added into the waste water containing bisulfite to carry out catalytic disproportionation on bisulfite ions, the reaction temperature is controlled to be about 50 ℃, and after reaction for a period of time, the solution becomes light yellow. Filtering to separate out sulfur-containing activated carbon, and continuing to react the residual filtrate at 70-100 ℃ until sulfur precipitates are generated and clear supernatant is obtained, namely, the reaction is finished (the residual filtrate is sulfur colloid, and continuing to perform heating reaction to destabilize the colloid and form sulfur particles).
In the invention, SRG washing wastewater is conveyed into a carbon-liquid separation tank through a wastewater conveying device, and after standing and settling are carried out in the carbon-liquid separation tank, activated carbon powder in the SRG washing wastewater is separated. Meanwhile, part of the supernatant of the carbon liquid separation tank is extracted into an acidification treatment tank, then acid (sulfuric acid and/or sulfurous acid) is added to adjust the pH value of the wastewater in the acidification treatment tank to be less than 3 (preferably to adjust the pH value to be less than 2), and then activated carbon powder (which can be additionally added with new activated carbon powder according to the working condition requirement) separated from the SRG wastewater before is added for sedimentation and adsorption. Separating sulfur-containing activated carbon with adsorbed sulfur for later use after adsorption. And the wastewater from which the sulfur-containing activated carbon is separated is conveyed to a liquid mixing tank to be mixed with the original SRG wastewater.
In the invention, the sulfur-containing activated carbon adsorbed by sedimentation can be directly used for catalyzing the disproportionation reaction of the bisulfite in the SRG washing wastewater. Generally, in order to make the catalytic effect of the sulfur-containing activated carbon better, the sulfur-containing activated carbon generally needs to be subjected to multiple sedimentation adsorption treatments. Namely, a plurality of sedimentation adsorption tanks can be arranged at the same time, and then the sulfur-containing activated carbon is adsorbed in each sedimentation adsorption tank one by one. The wastewater of each sedimentation adsorption tank is from original SRG washing wastewater, and the wastewater after sedimentation adsorption is also conveyed to the liquid mixing tank to be mixed with the rest SRG washing wastewater. (the remaining portion of SRG washing wastewater refers to the original SRG washing wastewater after all SRG wastewater required for sedimentation and adsorption is removed).
In the present invention, the liquid mixing tank is used for sufficiently mixing the SRG wastewater after sedimentation adsorption with the remaining SRG wastewater, on one hand, for intensively realizing catalytic disproportionation of bisulfite in the SRG wastewater and on the other hand, for adjusting the acidity of the mixed wastewater to be consistent and for balancing the concentration of bisulfite ions contained in the mixed wastewater. And then conveying the uniformly mixed wastewater to a catalytic disproportionation pool for catalytic disproportionation.
In the invention, SRG washing wastewater containing bisulfite ions and activated carbon with certain content are simultaneously put into a catalytic disproportionation pool, and then heated to 40-80 ℃ (preferably 50-60 ℃) to carry out disproportionation reaction, so that the bisulfite ions in the wastewater are subjected to disproportionation reaction under the catalytic action of the activated carbon containing sulfur. Thereby realizing the purpose of reducing the bisulfite content of the SRG washing wastewater. SRG wastewater with the bisulfite content reduced is discharged into a wastewater post-treatment system for subsequent purification treatment.
In the invention, sulfur colloid generated by disproportionation reaction of hydrogen sulfite ions in the catalytic disproportionation pool is recycled to the colloid destabilization pool for further heating (for example, heating to 50-120 ℃, preferably heating to 70-100 ℃) destabilization reaction, and then sulfur simple substance with economic value is prepared and recycled.
In the invention, the waste water conveying device is a waste water conveying pipeline. The caliber is 0.1-100m, preferably 0.3-80m, more preferably 0..8-50m, and still more preferably 1-30m.
In the invention, the number of the wastewater conveying device, the carbon-liquid separation tank, the sedimentation adsorption tank, the catalytic disproportionation tank and the colloid destabilizing tank is 1-100, preferably 2-80, preferably 3-50, and more preferably 5-30 respectively.
In the invention, the volumes of the carbon liquid separation tank, the sedimentation adsorption tank, the catalytic disproportionation tank and the colloid destabilization tank are respectively and independently 1-100000000m 3 Preferably 2-50000000m 3 More preferably 3 to 10000000m 3 More preferably 5 to 1000000m 3 More preferably 10 to 500000m 3 。
In the present invention, the sulfur loading per gram of activated carbon is the sulfur content per unit mass of activated carbon in the sulfur-containing activated carbon after the embodiment provided by the present invention. I.e., the mass ratio of sulfur to activated carbon in the sulfur-containing activated carbon.
Compared with the prior art, the beneficial technical effects of the invention are as follows:
1. the invention adopts the active carbon contained in the SRG wastewater as an adsorption carrier, utilizes the colloidal sulfur released after the acidolysis of thiosulfate ions in the wastewater as a sulfur source, and has stronger adsorption effect through the active carbon powder or the active carbon particles. So that the colloidal sulfur separated out by the acidolysis of thiosulfate ions enters the activated carbon powder or the activated carbon particles to form the sulfur-containing activated carbon. The sulfur-containing activated carbon with excellent catalytic performance is prepared by changing waste into valuable under normal temperature and normal pressure through simple process conditions.
2. The sulfur-containing activated carbon synthesized by the method is used as a catalyst for the disproportionation reaction of the bisulfite (or the acidic solution of the sulfite), and has the advantages of low price, wide source, easy separation and recovery and long service life compared with the existing catalyst. And the sulfur-carrying activated carbon is used as a catalyst, so that elemental sulfur can be prepared and recovered at a lower temperature (about 50 ℃), the engineering application prospect is wide, and great economic benefits are achieved.
3. The invention innovatively adopts sulfur-containing activated carbon for the catalytic disproportionation reaction of bisulfite in cyanogen-containing SRG washing wastewater, thereby realizing the low-temperature catalytic disproportionation. The salt content of the washing wastewater is reduced, and simultaneously, the sulfur can be recovered, so that the resource utilization and treatment of the wastewater are realized, and no secondary pollution is generated.
4. The invention creatively provides a novel technology for desalting and desulfurizing by a disproportionation method based on the property of producing sulfur by bisulfite disproportionation, realizes the reduction of the content of salt in wastewater and the recovery of sulfur resources, and greatly reduces the consumption of liquid caustic soda in the subsequent wastewater treatment process (by about 60 percent through a comparison test). Provides a new way for the treatment and resource utilization of SRG washing wastewater.
Drawings
FIG. 1 is a flow chart of the method for catalytic desalination of SRG washing wastewater.
FIG. 2 is a schematic diagram of the system for catalytic desalination of SRG washing wastewater.
FIG. 3 is an overall structural diagram of a system for catalytic desalination of SRG washing wastewater according to the present invention.
FIG. 4 is a graph showing the comparison between the late alkali consumption of wastewater treated by the method of the present invention and the late alkali consumption of wastewater of the prior art.
Reference numerals: 1: a waste water conveying device; 2: a carbon-liquid separation tank; 3: a sedimentation adsorption tank; 4: a catalytic disproportionation pool; 5: a colloid destabilizing tank; 6: an acidification treatment tank; 601: an acid liquor conveying pipeline; 7: an active carbon cache bin; 8: a liquid mixing tank; 9: a sulfur-containing activated carbon cache; 10: a first solid-liquid separation device; 11: a second solid-liquid separation device; 12: a sulfur drying device; 1201: a shielding gas delivery conduit; 13: a wastewater post-treatment system; 14: a sulfur storage bin; l1: a first pipe; l2: a second conduit; l3: a third pipeline; l4: a fourth conduit; l5: a fifth pipeline; l6: a sixth pipeline; l7: a seventh pipe; s1: a first material conveying device; s2: a second material conveying device; s3: a third material conveying device; s4: a fourth material conveying device; s5: a fifth material conveying device; s6: a sixth material conveying device; s7: a seventh material conveying device; s8: an eighth material conveying device; s9: a ninth material conveying device; s10: a tenth material conveying device.
Detailed Description
The technical solutions of the present invention are illustrated below, and the claimed scope of the present invention includes, but is not limited to, the following examples.
A method for catalytic desalination of SRG washing wastewater comprises the following steps:
1) And (3) separating activated carbon powder from the SRG washing wastewater, adding acid into part of the SRG washing wastewater for acidification, mixing the activated carbon powder and the acidified part of the SRG washing wastewater, and performing sedimentation adsorption. Finally, carrying out solid-liquid separation to obtain the sulfur-containing activated carbon and the desulfurization wastewater.
2) Uniformly mixing the desulfurization wastewater and the residual SRG washing wastewater, and then adding sulfur-containing activated carbon to perform catalytic disproportionation reaction.
3) Continuously monitoring the pH value of the reaction system in the step 2) until the pH value is changed to a pH set value. Then carrying out solid-liquid separation to obtain filtrate.
4) And (4) continuously heating the filtrate obtained in the step 3) for reaction until precipitation is generated and a clear supernatant appears, and filtering to obtain sulfur and SRG washing wastewater after desalting.
Preferably, in step 1), the SRG washing wastewater is a cyanide-containing SRG washing wastewater.
Preferably, in step 1), the amount of the portion of the SRG washing wastewater used is such that the numerical ratio of the molar amount of thiosulfate (moL) in the portion of the SRG washing wastewater to the weight of activated carbon (g) is from 0.05 to 0.5, preferably from 0.1 to 0.3, more preferably from 0.15 to 0.25.
Preferably, in step 1), the acid is one or more of hydrochloric acid, sulfuric acid, nitric acid, nitrous acid, and phosphoric acid. Preferably sulfuric acid.
Preferably, in step 2), the disproportionation reaction is carried out at a temperature of 40 to 80 ℃, preferably 45 to 70 ℃, more preferably 50 to 60 ℃. The disproportionation reaction time is 0.3-10h, preferably 0.5-8h, more preferably 0.8-5h.
Preferably, in step 3), the pH set point is < 3, preferably the pH set point is < 2.5, more preferably the pH set point is < 2.
Preferably, in step 4), the reaction temperature of the heating reaction is 50 to 120 ℃, preferably 60 to 110 ℃, and more preferably 70 to 100 ℃.
Preferably, step 1) is specifically: the activated carbon powder in the SRG washing wastewater is separated for standby, then part of the SRG washing wastewater is taken, and acid (such as sulfuric acid) is added into the part of the SRG washing wastewater to adjust the pH value to be less than 3 (preferably pH value to be less than 2). Then adding the activated carbon powder into the acidified SRG wastewater for sedimentation adsorption (the adsorption time is 0.3-5h, preferably 0.5-3 h). And after adsorption, carrying out solid-liquid separation to obtain a solid and a filtrate, and drying the obtained solid to obtain the sulfur-containing activated carbon.
Preferably, the sulfur-containing activated carbon is activated carbon after multiple times of precipitation and adsorption, preferably 2 to 10 times, and more preferably 3 to 5 times. The SRG washing wastewater used for each settling adsorption is derived from the original SRG washing wastewater.
Preferably, step 2) is specifically: uniformly mixing the filtrate obtained after the solid-liquid separation in the step 1) with the residual SRG washing wastewater. Then adding sulfur-containing activated carbon, heating to 40-80 deg.C (preferably 50-60 deg.C), and performing disproportionation reaction for 0.3-10h (preferably 0.5-8 h) to obtain disproportionation reaction system, and performing step 3).
Preferably, step 3) is specifically: continuously monitoring the pH value of the disproportionation reaction system in the step 2), and filtering when the pH value of the disproportionation reaction system is lower than 3 (preferably lower than 2), separating sulfur-containing activated carbon and obtaining filtrate. Returning the sulfur-containing activated carbon to the step 2) to be continuously used as the catalyst, and performing the step 4) on the filtrate.
Preferably, the step 4) is specifically: heating the filtrate obtained in step 3) to 50-120 deg.C (preferably 70-100 deg.C) to react until sulfur precipitate and clear supernatant is obtained. Then separating out sulfur precipitate, drying to obtain elemental sulfur, and discharging the supernatant after the sulfur precipitate is separated out and treated by a wastewater post-treatment system.
Example 1
As shown in figure 2, the system for the catalytic desalination of the SRG washing wastewater comprises a wastewater conveying device 1, a carbon-liquid separation tank 2, a sedimentation adsorption tank 3, a catalytic disproportionation tank 4 and a colloid destabilizing tank 5. The waste water conveying device 1 is communicated with a feed inlet of the carbon-liquid separation tank 2. The carbon liquid separation tank 2, the sedimentation adsorption tank 3, the catalytic disproportionation tank 4 and the colloid destabilization tank 5 are sequentially connected in series.
Example 2
Example 1 is repeated as shown in fig. 3 except that the system further comprises an acidification treatment tank 6, and the acidification treatment tank 6 is positioned between the carbon-liquid separation tank 2 and the sedimentation adsorption tank 3. And the water outlet of the carbon-liquid separation tank 2 is communicated with the water inlet of the acidification tank 6 through a first pipeline L1. And the water outlet of the acidification treatment pool 6 is communicated with the water inlet of the sedimentation adsorption pool 3 through a second pipeline L2. An acid liquor conveying pipeline 601 is connected to an acid inlet of the acidification tank 6.
Example 3
Example 2 is repeated except that the system further comprises a charcoal buffer bin 7. The activated carbon buffer storage bin 7 is positioned between the carbon liquid separation tank 2 and the sedimentation adsorption tank 3. The discharge hole of the carbon-liquid separation tank 2 is communicated with the feed inlet of the activated carbon buffer storage bin 7 through a first material conveying device S1. The discharge outlet of the sexual carbon buffer storage bin 7 is communicated with the feed inlet of the sedimentation adsorption tank 3 through a second material conveying device S2.
Example 4
Example 3 was repeated except that the system further included a mixing tank 8. The liquid mixing tank 8 is positioned between the sedimentation adsorption tank 3 and the catalytic disproportionation tank 4. And the water outlet of the sedimentation adsorption tank 3 is communicated with the water inlet of the liquid mixing tank 8 through a third pipeline L3. The water outlet of the carbon-liquid separation tank 2 is also communicated with the water inlet of the liquid mixing tank 8 through a fourth pipeline L4. The water outlet of the liquid mixing pool 8 is communicated with the water inlet of the catalytic disproportionation pool 4 through a fifth pipeline L5.
Example 5
Example 4 was repeated except that the system further included a sulfur-containing activated carbon buffer bin 9. The sulfur-containing activated carbon buffer bin 9 is positioned between the sedimentation adsorption tank 3 and the catalytic disproportionation tank 4. The discharge outlet of the sedimentation adsorption tank 3 is communicated with the feed inlet of the sulfur-containing activated carbon buffer storage bin 9 through a third material conveying device S3. And the discharge port of the sulfur-containing activated carbon buffer bin 9 is communicated with the feed inlet of the catalytic disproportionation pool 4 through a fourth material conveying device S4.
Example 6
The embodiment 5 is repeated, except that the discharge port of the sulfur-containing activated carbon buffer storage bin 9 is also communicated with the feed inlet of the sedimentation adsorption tank 3 through a fifth material conveying device S5.
Example 7
Example 6 is repeated except that the system further comprises a first solid liquid separation device 10. The first solid-liquid separation device 10 is positioned between the catalytic disproportionation tank 4 and the colloid destabilizing tank 5. And a discharge port of the catalytic disproportionation tank 4 is connected with a feed port of the first solid-liquid separation device 10 through a sixth material conveying device S6. The water outlet of the first solid-liquid separation device 10 is communicated with the water inlet of the colloid destabilizing tank 5 through a sixth pipeline L6.
Example 8
Example 7 was repeated except that the discharge port of the first solid-liquid separating device 10 was also communicated with the feed port of the catalytic disproportionation tank 4 via a seventh material conveying device S7.
Example 9
Example 8 is repeated except that the system further comprises a second solid liquid separation device 11. And a feed inlet of the second solid-liquid separation device 11 is communicated with a discharge outlet of the colloid destabilizing tank 5 through an eighth material conveying device S8. A discharge port of the second solid-liquid separation device 11 is connected with a ninth material conveying device S9, and a water discharge port of the second solid-liquid separation device 11 is connected with a seventh pipeline L7.
Example 10
Example 9 is repeated except that the system further comprises a sulphur drying unit 12. And a feed inlet of the sulfur drying device 12 is communicated with a discharge outlet of the second solid-liquid separation device 11 through a ninth material conveying device S9. And a protective gas conveying pipeline 1201 is connected to the gas inlet of the sulfur drying device 12.
Example 11
Example 10 is repeated except that the system also includes a wastewater after-treatment system 13. The water inlet of the wastewater post-treatment system 13 is communicated with the water outlet of the second solid-liquid separation device 11 through a seventh pipeline L7.
Example 12
Example 11 is repeated except that the system further comprises a sulphur storage silo 14. The sulfur storage bin 14 is communicated with a discharge port of the sulfur drying device 12 through a tenth material conveying device S10.
Example 13
Taking cyanogen-containing SRG wastewater of 5.0m 3 And the content of thiosulfate ions in the wastewater is 911mg/L and the content of the activated carbon is 82mg/L.
Firstly, the active carbon powder in the cyanide-containing SRG washing wastewater is separated, and then 2.0m of the active carbon powder is taken 3 The cyanogen-containing SRG washes the waste water, and sulfuric acid is added into the part of the waste water to adjust the pH value to be less than 3. Then adding activated carbon powder into the acidified cyanide-containing SRG wastewater at normal temperature and normal pressure for sedimentation and adsorption for 2 hours. And after adsorption, carrying out solid-liquid separation to obtain a solid I and a filtrate I, and drying the obtained solid I at 80 ℃ for 1h to obtain the sulfur-containing activated carbon I.
Example 14
5.0m of cyanogen-containing SRG wastewater is taken 3 And detecting that the content of sulfate ions in the wastewater is 1209mg/L and the content of the activated carbon is 71mg/L.
Firstly, separating the active carbon powder in the cyanide-containing SRG washing wastewater, and then taking 2.5m 3 The cyanogen-containing SRG washes the waste water, and sulfuric acid is added into the part of the waste water to adjust the pH value to be less than 2. Then adding activated carbon powder into the acidified cyanide-containing SRG wastewater at normal temperature and normal pressure for sedimentation and adsorption for 2 hours. And after adsorption, carrying out solid-liquid separation to obtain a solid II and a filtrate II, and drying the obtained solid II at 70 ℃ for 2 hours to obtain the sulfur-containing activated carbon II.
Example 15
Example 13 is repeated, except that a further 1.0m is taken 3 The cyanogen-containing SRG washes the waste water, and sulfuric acid is added into the part of the waste water to adjust the pH value to be less than 2. Then adding sulfur-containing activated carbon I into the acidified cyanide-containing SRG wastewater at normal temperature and normal pressure for settling and adsorbing for 1h. And after adsorption, carrying out solid-liquid separation to obtain solid III and filtrate III, and drying the obtained solid III at 70 ℃ for 2h to obtain the sulfur-containing activated carbon III.
Example 16
Example 13 is repeated, except that filtrate I and the remaining 3.0m 3 The cyanogen-containing SRG washing wastewater is uniformly mixed, and the concentration of bisulfite ions in the mixed washing wastewater is detected to be 64.67g/L. Then adding sulfur-containing activated carbon I, and heating to 55 ℃ for disproportionation reaction; and continuously monitoring the pH value of the reaction system, filtering when the pH value of the reaction system is lower than 2, separating sulfur-containing activated carbon and obtaining filtrate. The filtrate was heated to 90 ℃ and the reaction was continued until sulfur precipitate was formed and a clear supernatant was obtained. The sulphur precipitate was then separated and dried at 80 ℃ for 2h under nitrogen protection to obtain 39.01kg of elemental sulphur. The content of the bisulfate ion in the wastewater after catalytic desulfurization is detected to be 0.56g/L.
Example 17
Example 14 is repeated, except that filtrate II and the remaining 2.5m 3 The cyanogen-containing SRG washing wastewater is uniformly mixed, and the concentration of bisulfite ions in the mixed washing wastewater is detected to be 60.94g/L. Then adding sulfur-containing activated carbon I, and heating to 55 ℃ for disproportionation reaction; and continuously monitoring the pH value of the reaction system, filtering when the pH value of the reaction system is lower than 2, separating sulfur-containing activated carbon and obtaining filtrate. The filtrate was heated to 90 ℃ and the reaction was continued until sulfur precipitate was formed and a clear supernatant was obtained. The sulphur precipitate was then separated and dried at 80 ℃ for 2h under nitrogen protection to obtain 36.88kg of elemental sulphur. The content of the bisulfate ion in the wastewater after catalytic desulfurization is detected to be 0.80g/L.
Example 18
Example 15 was repeated except that filtrate I, filtrate III and the remaining 2.0m 3 SRG wash containing cyanogenThe washing wastewater is uniformly mixed, and the concentration of bisulfite ions in the mixed washing wastewater is detected to be 62.73g/L. Then adding sulfur-containing activated carbon III, and heating to 55 ℃ for disproportionation reaction; and continuously monitoring the pH value of the reaction system, filtering when the pH value of the reaction system is lower than 2, separating sulfur-containing activated carbon and obtaining filtrate. The filtrate was heated to 90 ℃ and the reaction was continued until sulfur precipitate was formed and a clear supernatant was obtained. The sulphur precipitate was then separated and dried at 80 ℃ for 2h under nitrogen protection to obtain 37.25kg of elemental sulphur. The content of the bisulfate ion in the wastewater after catalytic desulfurization was detected to be 0.42g/L.

Claims (10)

1. A method for catalytic desalination of SRG washing wastewater is characterized by comprising the following steps: the method comprises the following steps:
1) Separating activated carbon powder from SRG washing wastewater, adding acid into part of SRG washing wastewater for acidification, mixing the activated carbon powder with the acidified part of SRG washing wastewater, and performing sedimentation adsorption; finally, carrying out solid-liquid separation to obtain sulfur-containing activated carbon and desulfurization wastewater;
2) Uniformly mixing the desulfurization wastewater and the residual SRG washing wastewater, and then adding sulfur-containing activated carbon to perform catalytic disproportionation reaction;
3) Continuously monitoring the pH value of the reaction system in the step 2) until the pH value is changed to a pH set value; then carrying out solid-liquid separation to obtain filtrate;
4) And (3) continuously heating the filtrate obtained in the step 3) for reaction until precipitates are generated and a relatively clear supernatant appears, and filtering to obtain sulfur and desalted SRG washing wastewater.
2. The method of claim 1, wherein: in the step 1), the SRG washing wastewater is cyanogen-containing SRG washing wastewater;
the amount of the portion of the SRG washing wastewater used is such that the numerical ratio of the molar amount of thiosulfate (moL) in the portion of the SRG washing wastewater to the weight of activated carbon (g) is from 0.05 to 0.5, preferably from 0.1 to 0.3, more preferably from 0.15 to 0.25;
the acid is one or more of hydrochloric acid, sulfuric acid, nitric acid, nitrous acid and phosphoric acid; preferably sulfuric acid.
3. A method according to claim 2 or 3, characterized in that: in step 2), the temperature of the disproportionation reaction is 40-80 ℃, preferably 45-70 ℃, and more preferably 50-60 ℃; the time of the disproportionation reaction is 0.3-10h, preferably 0.5-8h, and more preferably 0.8-5h; and/or
In step 3), the pH set value is less than 3, preferably less than 2.5, more preferably less than 2; and/or
In step 4), the reaction temperature of the heating reaction is 50 to 120 ℃, preferably 60 to 110 ℃, and more preferably 70 to 100 ℃.
4. The method of claim 3, wherein: the step 1) is specifically as follows: separating activated carbon powder from SRG washing wastewater for later use, taking part of SRG washing wastewater, and adding acid (such as sulfuric acid) into the part of SRG washing wastewater to adjust the pH to be less than 3 (preferably to be less than 2); then adding the activated carbon powder into the acidified SRG wastewater for sedimentation adsorption (the adsorption time is 0.3-5h, preferably 0.5-3 h); after adsorption, carrying out solid-liquid separation to obtain a solid and a filtrate, and drying the obtained solid to obtain sulfur-containing activated carbon;
preferably, the sulfur-containing activated carbon is activated carbon subjected to multiple times of sedimentation adsorption, preferably 2 to 10 times, and more preferably 3 to 5 times; the SRG washing wastewater used for each settling adsorption is derived from the original SRG washing wastewater.
5. The method according to claim 3 or 4, characterized in that: the step 2) is specifically as follows: uniformly mixing the filtrate obtained after the solid-liquid separation in the step 1) with the residual SRG washing wastewater; then adding sulfur-containing activated carbon, heating to 40-80 ℃ (preferably 50-60 ℃) to perform disproportionation reaction for 0.3-10h (preferably 0.5-8 h) to obtain a disproportionation reaction system, and then performing step 3); and/or
The step 3) is specifically as follows: continuously monitoring the pH value of the disproportionation reaction system in the step 2), and filtering when the pH value of the disproportionation reaction system is lower than 3 (preferably lower than 2), so as to separate sulfur-containing activated carbon and obtain filtrate; returning the sulfur-containing activated carbon to the step 2) to be continuously used as a catalyst, and performing the step 4) on the filtrate; and/or
The step 4) is specifically as follows: continuously heating the filtrate obtained in the step 3) to 50-120 ℃ (preferably 70-100 ℃) for reaction until sulfur precipitates and a clear supernatant is obtained; then separating out sulfur precipitate, drying to obtain elemental sulfur, and discharging the supernatant after the sulfur precipitate is separated out and treated by a wastewater post-treatment system.
6. The utility model provides a system for SRG washing waste water catalysis desalination which characterized in that: the system comprises a wastewater conveying device (1), a carbon-liquid separation tank (2), a sedimentation adsorption tank (3), a catalytic disproportionation tank (4) and a colloid destabilizing tank (5); the waste water conveying device (1) is communicated with a feed inlet of the carbon-liquid separation tank (2); the carbon-liquid separation tank (2), the sedimentation adsorption tank (3), the catalytic disproportionation tank (4) and the colloid destabilization tank (5) are sequentially connected in series.
7. The system of claim 6, wherein: the system also comprises an acidification treatment pool (6), wherein the acidification treatment pool (6) is positioned between the carbon-liquid separation pool (2) and the sedimentation adsorption pool (3); the water outlet of the carbon-liquid separation tank (2) is communicated with the water inlet of the acidification tank (6) through a first pipeline (L1); the water outlet of the acidification treatment pool (6) is communicated with the water inlet of the sedimentation adsorption pool (3) through a second pipeline (L2); an acid liquor conveying pipeline (601) is connected to an acid inlet of the acidification treatment pool (6); and/or
The system also comprises an active carbon buffer storage bin (7); the activated carbon buffer storage bin (7) is positioned between the carbon-liquid separation tank (2) and the sedimentation adsorption tank (3); a discharge port of the carbon-liquid separation tank (2) is communicated with a feed port of the activated carbon buffer storage bin (7) through a first material conveying device (S1); and the discharge port of the charcoal buffer storage bin (7) is communicated with the feed port of the sedimentation adsorption tank (3) through a second material conveying device (S2).
8. The system according to claim 6 or 7, characterized in that: the system also comprises a liquid mixing tank (8); the liquid mixing tank (8) is positioned between the sedimentation adsorption tank (3) and the catalytic disproportionation tank (4); the water outlet of the sedimentation adsorption tank (3) is communicated with the water inlet of the liquid mixing tank (8) through a third pipeline (L3); the water outlet of the carbon-liquid separation tank (2) is also communicated with the water inlet of the liquid mixing tank (8) through a fourth pipeline (L4); the water outlet of the liquid mixing pool (8) is communicated with the water inlet of the catalytic disproportionation pool (4) through a fifth pipeline (L5); and/or
The system also comprises a sulfur-containing activated carbon buffer bin (9); the sulfur-containing activated carbon buffer bin (9) is positioned between the sedimentation adsorption tank (3) and the catalytic disproportionation tank (4); the discharge port of the sedimentation adsorption tank (3) is communicated with the feed inlet of the sulfur-containing activated carbon buffer storage bin (9) through a third material conveying device (S3); the discharge port of the sulfur-containing activated carbon buffer bin (9) is communicated with the feed inlet of the catalytic disproportionation pool (4) through a fourth material conveying device (S4);
preferably, the discharge port of the sulfur-containing activated carbon buffer storage bin (9) is communicated with the feed inlet of the sedimentation adsorption tank (3) through a fifth material conveying device (S5).
9. The system according to any one of claims 6-8, wherein: the system further comprises a first solid-liquid separation device (10); the first solid-liquid separation device (10) is positioned between the catalytic disproportionation tank (4) and the colloid destabilizing tank (5); a discharge port of the catalytic disproportionation tank (4) is connected with a feed port of the first solid-liquid separation device (10) through a sixth material conveying device (S6); the water outlet of the first solid-liquid separation device (10) is communicated with the water inlet of the colloid destabilizing pool (5) through a sixth pipeline (L6);
preferably, the discharge port of the first solid-liquid separation device (10) is also communicated with the feed port of the catalytic disproportionation pool (4) through a seventh material conveying device (S7);
preferably, the system further comprises a second solid-liquid separation device (11); a feed inlet of the second solid-liquid separation device (11) is communicated with a discharge outlet of the colloid destabilizing tank (5) through an eighth material conveying device (S8); and a discharge port of the second solid-liquid separation device (11) is connected with a ninth material conveying device (S9), and a water discharge port of the second solid-liquid separation device (11) is connected with a seventh pipeline (L7).
10. The system of claim 9, wherein: the system also comprises a sulfur drying device (12); a feed inlet of the sulfur drying device (12) is communicated with a discharge outlet of the second solid-liquid separation device (11) through a ninth material conveying device (S9); a protective gas conveying pipeline (1201) is connected to the gas inlet of the sulfur drying device (12);
preferably, the system also comprises a waste water post-treatment system (13); a water inlet of the wastewater post-treatment system (13) is communicated with a water outlet of the second solid-liquid separation device (11) through a seventh pipeline (L7);
preferably, the system also comprises a sulfur storage bin (14); the sulfur storage bin (14) is communicated with a discharge port of the sulfur drying device (12) through a tenth material conveying device (S10).
CN202110359165.8A 2021-04-02 2021-04-02 Method for catalyzing and desalting SRG washing wastewater and system for catalyzing and desalting SRG washing wastewater Active CN115180753B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110359165.8A CN115180753B (en) 2021-04-02 2021-04-02 Method for catalyzing and desalting SRG washing wastewater and system for catalyzing and desalting SRG washing wastewater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110359165.8A CN115180753B (en) 2021-04-02 2021-04-02 Method for catalyzing and desalting SRG washing wastewater and system for catalyzing and desalting SRG washing wastewater

Publications (2)

Publication Number Publication Date
CN115180753A true CN115180753A (en) 2022-10-14
CN115180753B CN115180753B (en) 2023-12-29

Family

ID=83512291

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110359165.8A Active CN115180753B (en) 2021-04-02 2021-04-02 Method for catalyzing and desalting SRG washing wastewater and system for catalyzing and desalting SRG washing wastewater

Country Status (1)

Country Link
CN (1) CN115180753B (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101474551A (en) * 2008-12-22 2009-07-08 重庆大学 S-loaded activated carbon for mercury removal from flue gas and preparation method thereof
CN103274366A (en) * 2013-05-23 2013-09-04 中南大学 Method for efficiently recycling elemental sulfur in process of treating sulfur dioxide flue gas by using sodium sulfide
CN108939767A (en) * 2018-07-13 2018-12-07 中冶长天国际工程有限责任公司 A method of the purification of the wet high-effective of flue gas containing elemental sulfur
CN109970243A (en) * 2019-04-26 2019-07-05 苏州艾吉克膜科技有限公司 The removal technique of elemental sulfur in a kind of desulphurization denitration Wastewater from Acid Preparation
CN110124490A (en) * 2018-02-02 2019-08-16 中冶长天国际工程有限责任公司 A kind of active carbon handles the method and device thereof of multi-pollutant flue gas and waste water reuse

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101474551A (en) * 2008-12-22 2009-07-08 重庆大学 S-loaded activated carbon for mercury removal from flue gas and preparation method thereof
CN103274366A (en) * 2013-05-23 2013-09-04 中南大学 Method for efficiently recycling elemental sulfur in process of treating sulfur dioxide flue gas by using sodium sulfide
CN110124490A (en) * 2018-02-02 2019-08-16 中冶长天国际工程有限责任公司 A kind of active carbon handles the method and device thereof of multi-pollutant flue gas and waste water reuse
CN108939767A (en) * 2018-07-13 2018-12-07 中冶长天国际工程有限责任公司 A method of the purification of the wet high-effective of flue gas containing elemental sulfur
CN109970243A (en) * 2019-04-26 2019-07-05 苏州艾吉克膜科技有限公司 The removal technique of elemental sulfur in a kind of desulphurization denitration Wastewater from Acid Preparation

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
吴博;黄戒介;张荣俊;赵建涛;陈富艳;王洋;: "活性炭(焦)低温吸附催化脱除H_2S的基础研究", 燃料化学学报, no. 03 *

Also Published As

Publication number Publication date
CN115180753B (en) 2023-12-29

Similar Documents

Publication Publication Date Title
CN107213774B (en) Flue gas desulfurization and resource utilization method based on smelting tailing slag
CN105060545A (en) System and method for softening treatment of desulfurization wastewater of coal-fired power plant
CN102070198A (en) Method for preparing high-purity manganese sulfate and high-purity manganese carbonate by reduction leaching of pyrolusite through scrap iron
CN102936070A (en) Method for treating mercury-containing wastewater during PVC (Polyvinyle Chloride) production through two-step process
CN110745989B (en) Activated carbon flue gas purification acid-making wastewater zero-discharge process and system
CN110550651A (en) Method for producing zinc sulfide by using acidic waste gas
CN113087266A (en) Control method suitable for zero discharge of sintering pellet desulfurization and denitrification acid making wastewater
CN117185527A (en) Chemical industry incineration flue gas high-ammonium salt spray wastewater recycling method and system for simultaneously recycling magnesium ammonium phosphate and ammonium sulfate
CN115180753B (en) Method for catalyzing and desalting SRG washing wastewater and system for catalyzing and desalting SRG washing wastewater
CN215288069U (en) System for SRG washing wastewater catalytic desalination
CN1280032A (en) Special device for processing so2 containing fume
CN109095731A (en) A kind of system based on magnesium processes desulfurization wastewater high-purity magnesium hydroxide
CN214115239U (en) Titanium white powder dust collection waste residue water resourceful treatment system by chlorination process
CN114053839B (en) Method and system for cleaning and treating cyanide-containing SRG gas and purifying tail gas of hot blast stove
CN113087104B (en) System and method for preparing elemental sulfur through liquid-phase catalytic disproportionation
CN104211122B (en) With the decomposition precipitation circulation technology of preparing manganous-manganic oxide by manganese sulphate solution
CN209338324U (en) A kind of system based on magnesium processes desulfurization wastewater high-purity magnesium hydroxide
CN113173632B (en) Horizontal liquid-phase catalytic disproportionation and destabilization sulfur-separation system and treatment method thereof
CN113173634B (en) Catalytic treatment system for bisulfite-containing wastewater and wastewater treatment method
CN113289473A (en) Method for treating heavy metal before smelting flue gas desulfurization
CN115180752B (en) Desalination method for SRG washing wastewater by catalyzing sulfur-containing activated carbon
CN113173633B (en) Vertical liquid-phase catalytic disproportionation and destabilization sulfur-separation system and treatment method thereof
CN111892222A (en) Ammonium sulfate wastewater recycling method
CN110357164A (en) The method that manganese oxide ore pulp recycles high-efficiency flue gas desulfurization coupling manganese sulfate green purifying
CN110921958A (en) Acid-making wastewater recycling system and method by sintering flue gas activated carbon desulfurization process

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