Formula of cyanide remover for total cyanide wastewater in coal chemical industry

Abstract

The invention relates to the technical field of wastewater processing, and discloses a cyanide remover formula for total cyanide wastewater in coal chemical industry, which comprises the following steps: S1, preparation of formula materials: the raw materials to be prepared comprise calcium hypochlorite, hydrogen peroxide, ferrous sulfate, polyferric sulfate and lime, and the dosage of the calcium hypochlorite is adjusted according to the concentration of cyanide in the wastewater; generally, 50-100g of calcium hypochlorite can be added into per cubic meter of wastewater, 100-200ml of hydrogen peroxide can be added into per cubic meter of wastewater, and 50-100g of ferrous sulfate can be added into per cubic meter of wastewater. According to the cyanide remover formula for the total cyanide wastewater in the coal chemical industry, calcium hypochlorite and hydrogen peroxide serve as strong oxidants, cyanide can be directly oxidized into low-toxicity or non-toxic substances, the oxidation capacity far exceeds that of aluminum salt and ferric salt in a comparison case, and the oxidation reaction speed is high; the cyanide can be effectively removed within a short time, and the treatment efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater processing, in particular to a formula of a cyanide remover for total cyanide wastewater in coal chemical industry. Background Art

[0002] With the continuous growth of energy demand, the coal chemical industry has developed rapidly around the world. In the coal chemical process, a large amount of wastewater is generated, which contains a variety of pollutants, such as cyanide, phenols, ammonia nitrogen, and heavy metals. Total cyanide wastewater is a typical wastewater in coal chemical wastewater, which has a high cyanide content and is extremely harmful to the environment and human health.

[0003] The prior art discloses a cyanide remover formula for coking phenol-cyanide wastewater with announcement number: CN113105039A, which comprises the following steps: step one: stirring a flocculant and an organic anionic flocculant polyacrylamide in proportion; step two: adding an appropriate amount of a coagulant aid during stirring, and stirring to obtain a primary solution; step three: standing the primary solution for 3 to 5 hours to observe whether stratification occurs, and if stratification occurs, continuing stirring, and then settling until no stratification occurs; step four: adding polyacrylamide to the solution without stratification, and mixing; step five: obtaining an aqueous solution, wherein the flocculant in the step one comprises aluminum sulfate, aluminum chloride, ferric sulfate, ferric chloride, polyaluminum chloride, polyaluminum sulfate, polyferric chloride and polysulfuric acid; through the above-mentioned design, the ability of the remover can be improved, and in use, the purification of cyanide wastewater is more thorough, while the dosage is reduced and the use cost is reduced, thereby improving the deficiencies in the prior art.

[0004] The above-mentioned cyanide remover formula for total cyanide wastewater from coal chemical industry can improve the ability of the remover. During use, the purification of cyanide wastewater is more thorough, while reducing the dosage and the use cost, thereby improving the deficiencies in the prior art. The above-mentioned device uses ferric sulfate, ferric chloride, polyaluminium chloride, polyaluminium sulfate, polyferric chloride and polysulfuric acid to remove cyanide, removes pollutants through flocculation, has limited oxidation capacity for cyanide, cannot oxidize cyanide into low-toxic or non-toxic substances, has low oxidation capacity, and may produce residual aluminium ions and iron ions during use, posing a certain threat to the environment. The effect during use is not good, and this needs to be improved. Summary of the invention

[0005] The purpose of the present invention is to provide a cyanide remover formula for total cyanide wastewater in coal chemical industry to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a cyanide removal agent formulation for total cyanide wastewater in coal chemical industry, comprising the following steps: S1. Preparation of formula materials The raw materials that need to be prepared include calcium hypochlorite, hydrogen peroxide, ferrous sulfate, polyferric sulfate and lime. The amount of calcium hypochlorite used depends on the concentration of cyanide in the wastewater. Generally, 50-100 grams of calcium hypochlorite can be added per cubic meter of wastewater, 100-200 milliliters of hydrogen peroxide can be added per cubic meter of wastewater, 50-100 grams of ferrous sulfate can be added per cubic meter of wastewater, and 50-100 grams of polyferric sulfate can be added per cubic meter of wastewater. The amount of lime is adjusted according to the pH value of the wastewater. 50-100 grams of lime can be added per cubic meter of wastewater.

[0007] S2. Adjust the pH value of wastewater Select a suitable pH adjuster, use lime and sodium peroxide, and adjust the pH value of the wastewater to about 8-10. This step requires the lime to be made into a lime milk suspension for addition. First, mix the lime powder with an appropriate amount of water and stir evenly to make lime milk. Then slowly add the lime milk to the wastewater through a metering pump or other dosing equipment. After the lime dissolves in the water, it will release hydroxide ions, thereby increasing the pH value of the wastewater. Lime also has a certain flocculation effect, which can help remove some suspended matter in the wastewater. Prepare sodium hydroxide into a solution of a certain concentration for addition. According to the volume of the wastewater and the pH value to be adjusted, calculate the required amount of sodium hydroxide, then dissolve it in water, and add it to the wastewater after making a solution.

[0008] S3, mixed processing Ensure that the wastewater has been adjusted to a pH of about 8-10 and is in a stirring state. A mechanical stirrer can be used to fully mix the wastewater so that the agent can be evenly dispersed in the wastewater. Accurately weigh the required calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate. An electronic scale can be used as a precise weighing tool to ensure that the amount of the agent is accurate. Add calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate in sequence according to the formula ratio. Stir slowly during the addition process to ensure that the agents are fully mixed. After a period of reaction, observe the changes in the color and turbidity of the wastewater. If the color of the wastewater becomes lighter and the turbidity decreases, it means that the reaction is in progress.

[0009] S4. Monitor pH value: During the dosing process, the pH value of the wastewater should be monitored in real time. A pH meter can be used for measurement so that the dosage can be adjusted in time to ensure that the pH value reaches the target range of about 8-10.

[0010] Preferably, the process of adding in S3 is to first add calcium hypochlorite, then add hydrogen peroxide in the second step, then add ferrous sulfate in the third step, and finally add polyferric sulfate. When adding calcium hypochlorite, the weighed calcium hypochlorite needs to be slowly added to the wastewater. A powder feeder can be used to evenly sprinkle calcium hypochlorite on the surface of the wastewater to avoid excessive local concentration caused by adding too much at one time. The color change and reaction of the wastewater are observed. The reaction of calcium hypochlorite and cyanide will produce certain color changes and bubbles, which is a normal reaction phenomenon.

[0011] Preferably, in S3, after the calcium hypochlorite is completely dissolved and fully reacts with the wastewater for a period of time, hydrogen peroxide is added. The hydrogen peroxide is slowly added to the wastewater, and a dropwise addition method can be used to control the addition speed and observe the reaction of the wastewater. The reaction of hydrogen peroxide and cyanide will generate a certain amount of heat, and the temperature of the wastewater may increase slightly. At the same time, a small amount of bubbles may be generated. If the reaction is found to be too violent or abnormal, the addition speed of hydrogen peroxide should be adjusted in time or the addition should be stopped.

[0012] Preferably, in S3, after hydrogen peroxide and wastewater have fully reacted for a period of time, ferrous sulfate is added. Ferrous sulfate is slowly added to the wastewater and can be evenly sprinkled on the surface of the wastewater using a powder feeder. During the addition of ferrous sulfate, the wastewater is kept in a stirring state. The reaction of ferrous sulfate and cyanide to form a complex is relatively slow, and sufficient stirring is required to ensure the complete reaction. The color change and reaction of the wastewater are observed. After the reaction of ferrous sulfate and cyanide, the color of the wastewater may change, which is a sign of complex formation. At the same time, a small amount of precipitation will be produced. If the reaction is abnormal, the amount of ferrous sulfate and the pH value parameters of the wastewater should be checked in time.

[0013] Preferably, in S3, after the ferrous sulfate and the wastewater have fully reacted for a period of time, polyferric sulfate is added, and the polyferric sulfate is slowly added to the wastewater and evenly sprinkled on the surface of the wastewater. During the process of adding the polyferric sulfate, the stirring state of the wastewater continues to be maintained. The polyferric sulfate has a flocculation effect and can flocculate and precipitate the generated complex and other impurities. Stirring can enable the polyferric sulfate to fully exert its flocculation effect and improve the precipitation effect.

[0014] Preferably, in S3, after adding polyferric sulfate, it is necessary to observe the flocculation of the wastewater. After the addition of polyferric sulfate, the wastewater will gradually become turbid, and then flocculation precipitation will begin to appear. If the flocculation effect is not obvious, the amount of polyferric sulfate can be appropriately increased, and the stirring speed can also be adjusted.

[0015] Preferably, when the color change is not obvious and there are too many bubbles when adding calcium hypochlorite in S3, the addition of calcium hypochlorite should be stopped in time, and the pH value of the wastewater should be checked to see if it is normal.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: 1. The cyanide remover formula for coal chemical total cyanide wastewater can directly oxidize cyanide into low-toxic or non-toxic substances by providing calcium hypochlorite and hydrogen peroxide as strong oxidants, and the oxidation capacity far exceeds that of aluminum salts and iron salts in comparative cases, and the oxidation reaction speed is fast, so that cyanide can be effectively removed in a shorter time, thereby improving the treatment efficiency.

[0017] 2. The cyanide remover formula for the total cyanide wastewater of the coal chemical industry is provided with ferrous sulfate and polyferric sulfate, which can not only act as flocculants, but also form stable complexes with cyanide to further reduce the toxicity of cyanide. In contrast, the aluminum sulfate, aluminum chloride and polyaluminum chloride in the comparative cases mainly remove pollutants by flocculation and precipitation, and have a weaker complexing effect on cyanide. The formation of the complex is conducive to the subsequent precipitation and separation treatment, thereby improving the stability of the removal effect.

[0018] 3. The cyanide remover formula for the total cyanide wastewater of the coal chemical industry is provided with lime, which can effectively adjust the pH value of the wastewater to make it within a range suitable for oxidation reaction and flocculation precipitation. Aluminum sulfate and aluminum chloride have better effects under acidic conditions and have a relatively narrow applicable range for pH values. By adjusting the amount of lime, the pH value of the wastewater can be flexibly controlled to meet the needs of different treatment stages and improve the adaptability of the treatment process.

[0019] 4. The formula of the cyanide remover for the total cyanide wastewater of the coal chemical industry is that calcium hypochlorite, hydrogen peroxide, ferrous sulfate, polyferric sulfate and lime have good synergistic effects. Calcium hypochlorite and hydrogen peroxide are used for oxidation, ferrous sulfate and polyferric sulfate are used for complexation and flocculation, and lime is used to adjust the pH value. The various agents cooperate with each other to achieve efficient removal of cyanide. In contrast, the combined use of aluminum sulfate, aluminum chloride aluminum salt and iron salt often lacks a clear synergistic mechanism, and the removal effect is relatively single. Calcium hypochlorite and hydrogen peroxide mainly generate non-toxic or low-toxic substances, such as oxygen and water, after the reaction, which have little impact on the environment. Some aluminum salts and iron salts may produce residual aluminum ions and iron ions during use, posing certain potential risks to the environment. Lime, as a natural substance, is also relatively environmentally friendly during use. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0021] The present invention provides a technical solution: a cyanide removal agent formula for total cyanide wastewater in coal chemical industry, comprising the following steps: S1. Preparation of formula materials The raw materials that need to be prepared include calcium hypochlorite, hydrogen peroxide, ferrous sulfate, polyferric sulfate and lime. The amount of calcium hypochlorite used depends on the concentration of cyanide in the wastewater. Generally, 50-100 grams of calcium hypochlorite can be added per cubic meter of wastewater, 100-200 milliliters of hydrogen peroxide can be added per cubic meter of wastewater, 50-100 grams of ferrous sulfate can be added per cubic meter of wastewater, and 50-100 grams of polyferric sulfate can be added per cubic meter of wastewater. The amount of lime is adjusted according to the pH value of the wastewater. 50-100 grams of lime can be added per cubic meter of wastewater.

[0022] S2. Adjust the pH value of wastewater Select a suitable pH adjuster, use lime and sodium peroxide, and adjust the pH value of the wastewater to about 8-10. This step requires the lime to be made into a lime milk suspension for addition. First, mix the lime powder with an appropriate amount of water and stir evenly to make lime milk. Then slowly add the lime milk to the wastewater through a metering pump or other dosing equipment. After the lime dissolves in the water, it will release hydroxide ions, thereby increasing the pH value of the wastewater. Lime also has a certain flocculation effect, which can help remove some suspended matter in the wastewater. Prepare sodium hydroxide into a solution of a certain concentration for addition. According to the volume of the wastewater and the pH value to be adjusted, calculate the required amount of sodium hydroxide, then dissolve it in water, and add it to the wastewater after making a solution.

[0023] S3, mixed processing Ensure that the wastewater has been adjusted to a pH value of about 8-10 and is in a stirring state. A mechanical stirrer can be used to fully mix the wastewater so that the agent can be evenly dispersed in the wastewater. Accurately weigh the required calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate. An electronic scale can be used as an accurate weighing tool to ensure that the amount of the agent is accurate. Add calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate in sequence according to the formula ratio. Stir slowly during the addition process to ensure that the agent is fully mixed. After a period of reaction, observe the changes in the color and turbidity of the wastewater. If the color of the wastewater becomes lighter and the turbidity decreases, it means that the reaction is in progress. The addition process is to add calcium hypochlorite first, hydrogen peroxide in the second step, and sulfuric acid in the third step. Ferrous iron, and finally add polyferric sulfate. When adding calcium hypochlorite, the weighed calcium hypochlorite needs to be slowly added to the wastewater. A powder feeder can be used to evenly sprinkle calcium hypochlorite on the surface of the wastewater to avoid adding too much at one time, which may cause excessive local concentration. Observe the color change and reaction of the wastewater. The reaction of calcium hypochlorite and cyanide will produce certain color changes and bubbles, which is a normal reaction phenomenon. When adding calcium hypochlorite, if the color change is not obvious or there are too many bubbles, stop adding calcium hypochlorite in time and check whether the pH value of the wastewater is normal. After the calcium hypochlorite is completely dissolved and fully reacts with the wastewater for a period of time, add hydrogen peroxide. Slowly add hydrogen peroxide to the wastewater. You can use a dropwise addition method to control the addition speed and observe. Observe the reaction of the wastewater. The reaction of hydrogen peroxide and cyanide will generate a certain amount of heat. The temperature of the wastewater may rise slightly. At the same time, a small amount of bubbles may be generated. If the reaction is found to be too violent or abnormal, the speed of adding hydrogen peroxide should be adjusted or stopped in time. After hydrogen peroxide and wastewater have fully reacted for a period of time, add ferrous sulfate. Slowly add ferrous sulfate to the wastewater. You can use a powder feeder to evenly sprinkle it on the surface of the wastewater. During the addition of ferrous sulfate, continue to keep the wastewater stirred. The reaction of ferrous sulfate and cyanide to form a complex is relatively slow, and sufficient stirring is required to ensure the complete reaction. Observe the color change and reaction of the wastewater. After the reaction of ferrous sulfate and cyanide, the color of the wastewater may change. This It is a sign of complex formation, and a small amount of precipitation will be produced at the same time. If the reaction is abnormal, the dosage of ferrous sulfate and the pH value parameters of the wastewater should be checked in time. After ferrous sulfate and wastewater have fully reacted for a period of time, add polyferric sulfate. Slowly add polyferric sulfate to the wastewater and sprinkle it evenly on the surface of the wastewater. During the addition of polyferric sulfate, continue to keep the wastewater stirred. Polyferric sulfate has a flocculation effect, which can flocculate and precipitate the generated complex and other impurities. Stirring can make polyferric sulfate give full play to its flocculation effect and improve the precipitation effect. After adding polyferric sulfate, it is necessary to observe the flocculation of the wastewater. After the addition of polyferric sulfate, the wastewater will gradually become turbid, and then flocculation precipitation will begin to appear. If the flocculation effect is not obvious,The amount of polyferric sulfate can be appropriately increased, and the stirring speed can also be adjusted.

[0024] S4. Monitor pH value: During the dosing process, the pH value of the wastewater should be monitored in real time. A pH meter can be used for measurement so that the dosage can be adjusted in time to ensure that the pH value reaches the target range of about 8-10.

[0025] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

Claims

1. A cyanide remover formula for total cyanide wastewater in coal chemical industry, characterized in that: The following steps are involved: S1. Preparation of formula materials The raw materials that need to be prepared include calcium hypochlorite, hydrogen peroxide, ferrous sulfate, polyferric sulfate and lime. The amount of calcium hypochlorite used depends on the concentration of cyanide in the wastewater. Generally, 50-100 grams of calcium hypochlorite can be added per cubic meter of wastewater. The amount of hydrogen peroxide is 100-200 milliliters per cubic meter of wastewater. The amount of ferrous sulfate can be added per cubic meter of wastewater. The amount of polyferric sulfate can be added per cubic meter of wastewater. 50-100 grams can be added per cubic meter of wastewater. The amount of lime is adjusted according to the pH value of the wastewater. 50-100 grams of lime can be added per cubic meter of wastewater. S2. Adjust the pH value of wastewater Select a suitable pH regulator, use lime and sodium peroxide, and adjust the pH value of the wastewater to about 8-10. This step requires lime to be made into a lime milk suspension for addition. First, lime powder is mixed with an appropriate amount of water and stirred evenly to make lime milk. Then, the lime milk is slowly added to the wastewater through a metering pump or other dosing equipment. After the lime dissolves in water, it releases hydroxide ions, thereby increasing the pH value of the wastewater. Lime also has a certain flocculation effect, which can help remove some suspended matter in the wastewater. Sodium hydroxide is prepared into a solution of a certain concentration for addition. According to the volume of the wastewater and the pH value to be adjusted, the required amount of sodium hydroxide is calculated, and then it is dissolved in water to make a solution and added to the wastewater; S3, mixed processing Ensure that the wastewater has been adjusted to a pH value of about 8-10 and is in a stirring state. A mechanical stirrer can be used to fully mix the wastewater so that the reagent can be evenly dispersed in the wastewater. Accurately weigh the required calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate. An electronic scale can be used as a precise weighing tool to ensure that the dosage of the reagent is accurate. Add calcium hypochlorite, hydrogen peroxide, ferrous sulfate and polyferric sulfate in sequence according to the formula ratio. Stir slowly during the addition process to fully mix the reagents. After a period of reaction, observe the changes in the color and turbidity of the wastewater. If the color of the wastewater becomes lighter and the turbidity decreases, it means that the reaction is in progress. S4. Monitor pH value: During the dosing process, the pH value of the wastewater should be monitored in real time. A pH meter can be used for measurement so that the dosage can be adjusted in time to ensure that the pH value reaches the target range of about 8-10.

2. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 1, characterized in that: The process of adding in S3 is to first add calcium hypochlorite, then add hydrogen peroxide in the second step, then add ferrous sulfate in the third step, and finally add polyferric sulfate. When adding calcium hypochlorite, the weighed calcium hypochlorite needs to be slowly added to the wastewater. A powder feeder can be used to evenly sprinkle the calcium hypochlorite on the surface of the wastewater to avoid excessive local concentration caused by adding too much at one time. The color change and reaction of the wastewater are observed. The reaction of calcium hypochlorite with cyanide will produce certain color changes and bubbles, which is a normal reaction phenomenon.

3. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 2, characterized in that: In the S3, after the calcium hypochlorite is completely dissolved and fully reacts with the wastewater for a period of time, hydrogen peroxide is added. The hydrogen peroxide is slowly added to the wastewater, and a dropwise addition method can be used to control the addition speed and observe the reaction of the wastewater. The reaction of hydrogen peroxide and cyanide will generate a certain amount of heat, and the temperature of the wastewater may increase slightly. At the same time, a small amount of bubbles may be generated. If the reaction is found to be too violent or abnormal, the addition speed of hydrogen peroxide should be adjusted in time or the addition should be stopped.

4. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 3, characterized in that: In S3, after hydrogen peroxide and wastewater have fully reacted for a period of time, ferrous sulfate is added. The ferrous sulfate is slowly added to the wastewater and can be evenly sprinkled on the surface of the wastewater using a powder feeder. During the addition of ferrous sulfate, the wastewater is kept in a stirring state. The reaction of ferrous sulfate and cyanide to form a complex is relatively slow, and sufficient stirring is required to ensure the complete reaction. The color change and reaction of the wastewater are observed. After the reaction of ferrous sulfate and cyanide, the color of the wastewater may change, which is a sign of complex formation. At the same time, a small amount of precipitation will be produced. If the reaction is abnormal, the amount of ferrous sulfate and the pH value parameters of the wastewater should be checked in time.

5. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 4, characterized in that: In the S3, after the ferrous sulfate and the wastewater have fully reacted for a period of time, polyferric sulfate is added. The polyferric sulfate is slowly added to the wastewater and evenly sprinkled on the surface of the wastewater. During the process of adding the polyferric sulfate, the wastewater is kept in a stirring state. The polyferric sulfate has a flocculation effect and can flocculate and precipitate the generated complex and other impurities. Stirring can enable the polyferric sulfate to fully exert its flocculation effect and improve the precipitation effect.

6. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 5, characterized in that: After adding polyferric sulfate in S3, the flocculation of the wastewater needs to be observed. After the addition of polyferric sulfate, the wastewater will gradually become turbid, and then flocculation and precipitation will begin to occur. If the flocculation effect is not obvious, the amount of polyferric sulfate can be appropriately increased, and the stirring speed can also be adjusted.

7. The cyanide removal agent formulation for coal chemical total cyanide wastewater according to claim 6, characterized in that: When the color change is not obvious and there are too many bubbles when adding calcium hypochlorite in S3, the addition of calcium hypochlorite should be stopped in time, and the pH value of the wastewater should be checked to see if it is normal.