CN112047548A - Device and process for comprehensive utilization and resource treatment of heavy metal-containing ammonium sulfate wastewater - Google Patents
Device and process for comprehensive utilization and resource treatment of heavy metal-containing ammonium sulfate wastewater Download PDFInfo
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Abstract
The invention provides a comprehensive utilization and resource treatment process of waste water containing heavy metal ammonium sulfate, which comprises the steps of crushing a calcium sulfate filter cake containing heavy metal, magnesium hydroxide and calcium hydroxide, then reacting the crushed calcium sulfate filter cake with sulfuric acid or hydrochloric acid, and controlling the reaction pH, so that the content of heavy metal, calcium hydroxide, magnesium hydroxide and other impurities in calcium sulfate solid is reduced to achieve the standard of the calcium sulfate solid; the invention also provides a device for purifying the ammonium sulfate wastewater containing heavy metals and by-product calcium sulfate, which comprises a first reaction device, a first filtering device, a second reaction device, a second filtering device, a first pH adjusting device, a first heavy metal filtering device, a second pH adjusting device, a magnesium hydroxide filtering device, a preheater, a stripping deamination device, a second heavy metal filtering device, a wastewater pH adjusting device, a sulfuric acid storage tank, a lime slurry storage tank, an ammonium sulfate wastewater storage tank and an alkali solution storage tank; the invention realizes the resource treatment of the ammonium sulfate wastewater containing heavy metal and magnesium.
Description
Technical Field
The invention relates to a recycling treatment method of heavy metal-containing magnesium-containing ammonium sulfate wastewater, in particular to a device and a process for comprehensive utilization and recycling treatment of heavy metal-containing ammonium sulfate wastewater.
Background
Ammonia nitrogen wastewater is generated in chemical industry, metallurgy field and electronic industry, and is an important pollution source. Ammonium salts contained in the ammonia nitrogen wastewater are generally ammonium sulfate or ammonium chloride, once the ammonium salts are discharged into water bodies, particularly lakes and gulfs with slow flow, the ammonium salts are easy to cause mass propagation of algae and other microorganisms in the water bodies, and are one of the main reasons for causing eutrophication of the water bodies. The ammonia nitrogen wastewater containing heavy metals is particularly high in harmfulness, and ammonia cannot be removed by a simple filtering method due to the complexation effect of the ammonia and most of the heavy metals, so that the harmfulness is higher if the ammonia nitrogen wastewater is discharged into a water body.
At present, the high-concentration waste water containing heavy metal ammonium sulfate mainly has the following two schemes. The method comprises the following steps: firstly, evaporating and crystallizing to obtain ammonium sulfate; and secondly, adding sodium hydroxide or sodium carbonate, then performing steam extraction deamination to obtain 20% ammonia water for recycling, filtering heavy metal from tower bottom liquid, and evaporating and crystallizing to obtain sodium sulfate for sale.
The first proposal has the problem of heavy metal treatment, for example, the evaporation crystallization of the ammonium sulfate wastewater containing heavy metals, because ammonia and part of heavy metals have complexation, the heavy metals such as nickel, cobalt, rare earth and the like in the ammonium sulfate are difficult to be completely pre-removed by resin and the like in the ammonia environment, and the heavy metals and the ammonium sulfate are difficult to be separated in the evaporation crystallization process, so that the final ammonium sulfate product contains heavy metals, which leads to the standard exceeding of the heavy metals of the ammonium sulfate and difficult to be sold out. And in the second scheme, sodium hydroxide is added to react with the ammonium sulfate wastewater to generate sodium sulfate and ammonia, ammonia water with the concentration of 20% is recovered by stripping deamination, heavy metal is filtered, the kettle liquid is evaporated and crystallized to obtain sodium sulfate crystals, and the sodium sulfate crystals are sold as anhydrous sodium sulphate after being dried. Moreover, the method adds a large amount of liquid caustic soda, resulting in high running cost.
Accordingly, there is a need for improvements in the art.
Disclosure of Invention
In order to solve the technical problems, the invention provides a comprehensive utilization and resource treatment process of heavy metal-containing ammonium sulfate wastewater, which comprises the following steps:
firstly, reacting ammonium sulfate wastewater containing heavy metals with calcium hydroxide, and controlling the pH value of the reaction to be between 11 and 12.5; filtering the solution to obtain a calcium sulfate dihydrate filter cake containing heavy metal hydroxides and a filtrate;
step two, carrying out steam stripping deamination on the filtrate obtained in the step one and the filtrate obtained in the step four to recover 20% ammonia water, filtering heavy metal hydroxide from tower bottom liquid, adjusting the pH value to be neutral, and then discharging the heavy metal hydroxide after reaching the standard;
step three, the calcium sulfate filter cake obtained in the step one is crushed and then is subjected to solid-liquid mixing reaction with sulfuric acid or hydrochloric acid, redundant calcium hydroxide and ammonia in the filter cake are reacted, heavy metal hydroxides in the calcium sulfate filter cake are reacted into soluble salts, the soluble salts are filtered to obtain a calcium sulfate dihydrate filter cake meeting the national standard and a filtrate, and the filter cake is sold or dried to prepare gypsum;
adding liquid alkali or calcium hydroxide into the filtrate obtained in the fourth step and the third step, controlling the pH value to be 8-9.5, precipitating heavy metal hydroxide, recycling after filtering, continuing to use the liquid alkali or the calcium hydroxide if magnesium sulfate exists in the ammonium sulfate wastewater, precipitating magnesium hydroxide, filtering, selling filter cakes, and stripping and deaminating the filtrate.
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
the first step comprises the following steps:
reacting the heavy metal magnesium-containing ammonium sulfate wastewater with the fourth filtrate in a first reaction device, adding 10-50% calcium hydroxide slurry to control the pH value to be 12, and then filtering by a first filtering device to obtain a first filter cake and a first filtrate;
the first filter cake is a calcium sulfate dihydrate filter cake containing heavy metal hydroxides, and the first filtrate is the filtrate obtained in the first step.
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
the second step comprises the following steps:
mixing the filtrate obtained in the first step with the filtrate obtained in the fourth step, preheating the mixture in a filtrate channel of a preheater, and then feeding the mixture into a stripping deamination device for stripping deamination to obtain tower bottom liquid and ammonia steam;
condensing the ammonia vapor to obtain ammonia water with the mass concentration of 20% for recycling;
the tower bottom liquid is sent to a preheater to preheat the filtrate, and then is filtered in a second heavy metal filtering device to obtain a fifth filter cake and a fifth filtrate;
and recovering the fifth filter cake as heavy metal, and feeding the fifth filtrate into a wastewater pH adjusting device, adding sulfuric acid or hydrochloric acid to adjust the pH to 6-9, and discharging the fifth filtrate after reaching the standard.
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
the third step comprises:
crushing the first filter cake by using a crusher, a ball mill or a high-speed stirrer and other equipment, then reacting the first filter cake with sulfuric acid with the mass concentration of 5-98% in a second reaction device, controlling the pH value to be 3-6, and reacting heavy metal, magnesium, ammonia and excessive calcium hydroxide in the first filter cake with the sulfuric acid to form soluble heavy metal sulfate, magnesium sulfate, ammonium sulfate and insoluble solid calcium sulfate dihydrate;
then filtering through a second filtering device to obtain a second filter cake and second filtrate;
taking the second filtrate as filtrate obtained in the third step;
the main component of the second filter cake is calcium sulfate dihydrate, which meets the national standard requirement, and gypsum is prepared by selling or drying;
the fourth step comprises the following steps:
adding liquid alkali or sodium carbonate into the second filtrate in the first pH adjusting device to adjust the pH to 8-9.5, forming precipitates of most heavy metals, and then filtering the precipitates by the first heavy metal filtering device to obtain a third filter cake and a third filtrate;
the third filter cake is heavy metal and is recycled together with the deaminated heavy metal;
adding liquid caustic soda or sodium carbonate into the third filtrate in a second pH adjusting device to adjust the pH to 11-12.5, forming a precipitate by magnesium sulfate, and filtering by a magnesium hydroxide filtering device to obtain a fourth filter cake and a fourth filtrate;
the fourth filter cake is subjected to selling treatment or drying pyrolysis to prepare magnesium oxide;
the fourth filtrate is ammonia-containing wastewater, wherein a small amount of sodium hydroxide, magnesium hydroxide, calcium sulfate and other substances are contained in the ammonia-containing wastewater, and the fourth filtrate is mixed with the first filtrate before being added into the preheater;
and taking the fourth filtrate as the filtrate obtained in the fourth step.
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
the pH was controlled at 12 by adding 10-50% calcium hydroxide slurry in step 1).
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
the pH of the bottom liquid is 10-12.5.
As an improvement of the comprehensive utilization and resource treatment process of the waste water containing the heavy metal ammonium sulfate, the method comprises the following steps:
discharged is wastewater for removing heavy metals and ammonia, wherein the wastewater contains a small amount of calcium sulfate, magnesium sulfate and wastewater containing part of soluble salts such as sodium chloride, sodium sulfate and the like.
The invention also provides a device for purifying the ammonium sulfate wastewater containing heavy metals and the byproduct calcium sulfate,
the device comprises a first reaction device, a first filtering device, a second reaction device, a second filtering device, a first pH adjusting device, a first heavy metal filtering device, a second pH adjusting device, a magnesium hydroxide filtering device, a preheater, a stripping deamination device, a second heavy metal filtering device, a wastewater pH adjusting device, a sulfuric acid storage tank, a lime slurry storage tank, an ammonium sulfate wastewater storage tank and an alkali solution storage tank;
the lime slurry storage tank and the ammonium sulfate wastewater storage tank are both connected with an inlet of the first reaction device;
the outlet of the first reaction device is connected with the inlet of the first filtering device;
a filter residue outlet of the first filtering device is connected with an inlet of the second reaction device, and a filtrate outlet of the first filtering device is connected with an inlet of a filtrate channel of the preheater;
the outlet of the filter liquid channel of the preheater is connected with the inlet of a stripping deamination device;
the sulfuric acid storage tank is connected with an inlet of the second reaction device;
the outlet of the second reaction device is connected with the inlet of the second filtering device;
the filter residue at the filter residue outlet of the second filtering device is a calcium sulfate dihydrate filter cake, and the calcium sulfate dihydrate filter cake is sold or dried; the filtrate outlet of the second filtering device is connected with the inlet of the first pH adjusting device;
the outlet of the alkali solution storage tank is respectively connected with the inlet of the first pH adjusting device and the inlet of the second pH adjusting device;
the outlet of the first pH adjusting device is connected with the inlet of the first heavy metal filtering device;
the filtrate outlet of the first heavy metal filtering device is connected with the inlet of the second pH adjusting device;
the outlet of the second pH adjusting device is connected with the inlet of the magnesium hydroxide filtering device;
the filtrate outlet of the magnesium hydroxide filtering device is connected with the inlet of a filtrate channel of the preheater;
the outlet at the bottom of the stripping deamination device is connected with the inlet of the second heavy metal filtering device after passing through a tower bottom liquid channel of the preheater;
and the filtrate outlet of the second heavy metal filtering device is connected with the inlet of the wastewater pH adjusting device.
As an improvement of the device for purifying the ammonium sulfate wastewater containing heavy metals and the byproduct calcium sulfate of the invention:
the first filtering device, the second filtering device, the first heavy metal filtering device and the magnesium hydroxide filtering device can be one or more of a plate-and-frame filter press, a disc vacuum filter, a vacuum belt filter and a centrifuge and are used for filtering slurry;
the first reaction device, the second reaction device, the first pH adjusting device, the second pH adjusting device and the wastewater pH adjusting device are all used for adjusting the pH value;
the preheater is used for preheating the solution;
the stripping deamination device is used for carrying out stripping deamination treatment on the ammonia-containing wastewater, the ammonia content of the deaminated wastewater is less than 10mg/L, and 20% ammonia water is recovered;
the sulfuric acid storage tank is used for storing a sulfuric acid solution with the mass concentration of 5-98% or hydrochloric acid with the mass concentration of 5-31%;
the lime slurry storage tank is used for storing 10-50% lime slurry;
the ammonium sulfate waste water storage tank is used for storing the ammonium sulfate waste water containing heavy metals to be treated;
the alkali solution storage tank is used for storing liquid alkali or sodium carbonate solution.
As an improvement of the device for purifying the ammonium sulfate wastewater containing heavy metals and the byproduct calcium sulfate of the invention:
the preheater is one of a tube heat exchanger, a plate heat exchanger or a spiral heat exchanger, and the filtrate and the tower bottom liquid are respectively arranged on two sides of the heat exchanger.
The device and the process for purifying the ammonium sulfate wastewater containing the heavy metals and the byproduct calcium sulfate have the technical advantages that:
the invention mainly solves the problems that the treatment cost of the waste water containing heavy metal ammonium sulfate is high and the by-product is difficult to reach the standard. Reacting the waste water containing heavy metal ammonium sulfate with calcium hydroxide slurry to obtain calcium sulfate dihydrate solid and free ammonia, stripping deamination and recovering 20% ammonia water, filtering the deamination waste water to adjust the pH value by heavy metal, and discharging the deamination waste water after reaching the standard. And the calcium sulfate dihydrate solid is purified to obtain calcium sulfate dihydrate meeting the national standard and then is used as gypsum. According to the method, the calcium hydroxide is used for replacing liquid caustic soda, so that the wastewater treatment cost is greatly reduced, the calcium sulfate dihydrate is subjected to purification treatment in the technical process, and excessive calcium hydroxide, heavy metals and magnesium hydroxide in the calcium sulfate are removed, so that the impurity content of the calcium sulfate is reduced to reach the national standard requirement, and the calcium sulfate is sold to be used as gypsum, and the problem of difficult selling of wastewater by-products is solved.
The calcium sulfate filter cake containing heavy metal, magnesium hydroxide and calcium hydroxide is firstly crushed and then reacts with sulfuric acid or hydrochloric acid, and the reaction pH is controlled, so that the content of heavy metal, calcium hydroxide, magnesium hydroxide and other impurities in the calcium sulfate solid is reduced to achieve the standard of the calcium sulfate solid;
adding liquid caustic soda into a reaction liquid of sulfuric acid and a calcium sulfate filter cake, controlling different pH values to precipitate different substances, and precipitating heavy metal hydroxides under the condition that the pH value is 8-9.5; under the condition that the pH value is 12-12.5, magnesium hydroxide is precipitated, so that magnesium in the wastewater is also recycled;
the invention realizes the resource treatment of the ammonium sulfate wastewater containing heavy metal and magnesium.
Drawings
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
FIG. 1 is a schematic view of a process for purifying heavy metal-containing ammonium sulfate wastewater and calcium sulfate byproduct.
Detailed Description
The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto.
Example 1, a device for purifying ammonium sulfate wastewater containing heavy metals and by-product calcium sulfate, as shown in fig. 1, includes a first reaction device 3, a first filter device 4, a second reaction device 5, a second filter device 7, a first pH adjusting device 9, a first heavy metal filter device 11, a second pH adjusting device 12, a magnesium hydroxide filter device 13, a preheater 15, a stripping deamination device 16, a second heavy metal filter device 17, a wastewater pH adjusting device 18, a sulfuric acid storage tank 6, a lime slurry storage tank 2, an ammonium sulfate wastewater storage tank 1, and an alkali solution storage tank 10.
The first filtering device 4, the second filtering device 7, the first heavy metal filtering device 11 and the magnesium hydroxide filtering device 13 can be one of a plate-and-frame filter press, a disc vacuum filter and a vacuum belt filter and are used for filtering slurry;
the first reaction device 3, the second reaction device 5, the first pH adjusting device 9, the second pH adjusting device 12 and the wastewater pH adjusting device 18 are all used for adjusting the pH value;
the preheater 15 is used for preheating the filtrate;
the stripping deamination device 16 is used for carrying out stripping deamination treatment on the ammonia-containing wastewater, and the ammonia content of the deaminated wastewater is less than 10 mg/L; recovering 20% ammonia water;
the sulfuric acid storage tank 6 is used for storing a sulfuric acid solution with the mass concentration of 5-98% or a hydrochloric acid solution with the mass concentration of 5-31%;
the lime slurry storage tank 2 is used for storing 10-50% lime slurry;
the ammonium sulfate waste water storage tank 1 is used for storing ammonium sulfate waste water containing heavy metals to be treated;
the caustic solution tank 10 is used for storing liquid caustic or sodium carbonate solution.
The lime slurry storage tank 2 and the ammonium sulfate waste water storage tank 1 are both connected with the inlet of the first reaction device 3,
the outlet of the first reaction device 3 is connected with the inlet of the first filtering device 4,
a filter residue outlet of the first filtering device 4 is connected with an inlet of the second reaction device 5, and a filtrate outlet of the first filtering device 4 is connected with an inlet of a filtrate channel of the preheater 15;
the outlet of the filter liquid channel of the preheater 15 is connected with the inlet of a stripping deamination device 16;
the sulfuric acid storage tank 6 is connected with the inlet of the second reaction device 5;
the outlet of the second reaction device 5 is connected with the inlet of a second filtering device 7;
the filter residue at the filter residue outlet of the second filtering device 7 is a calcium sulfate dihydrate filter cake, and the calcium sulfate dihydrate filter cake is sold or dried; the filtrate outlet of the second filtering device 7 is connected with the inlet of the first pH adjusting device 9;
the outlet of the alkali solution storage tank 10 is respectively connected with the inlet of the first pH adjusting device 9 and the inlet of the second pH adjusting device 12;
the outlet of the first pH adjusting device 9 is connected with the inlet of the first heavy metal filtering device 11;
filter residue at a filter residue outlet of the first heavy metal filtering device 11 is recovered as heavy metal, and a filtrate outlet of the first heavy metal filtering device 11 is connected with an inlet of the second pH adjusting device 12;
the outlet of the second pH adjusting device 12 is connected with the inlet of a magnesium hydroxide filtering device 13;
taking the filter residue at the filter residue outlet of the magnesium hydroxide filtering device 13 as a magnesium hydroxide filter cake for sale; the filtrate outlet of the magnesium hydroxide filtering device 13 is connected with the inlet of the filtrate channel of the preheater 15;
an outlet at the bottom of the stripping deamination device 16 passes through a tower bottom liquid channel of the preheater 15 and then is connected with an inlet of a second heavy metal filtering device 17; condensing ammonia steam at the outlet of the top of the stripping deamination device 16 through a condenser, refluxing a part of the ammonia steam, discharging a part of the ammonia steam to obtain ammonia water with the mass concentration of 20%, and recycling the ammonia water;
the filter residue at the filter residue outlet of the second heavy metal filtering device 17 is recovered as heavy metal, and the filtrate outlet of the second heavy metal filtering device 17 is connected with the inlet of the wastewater pH adjusting device 18;
the outlet of the wastewater pH adjusting device 18 is communicated with the outside for discharge.
The preheater 15 can be one of a tube heat exchanger, a plate heat exchanger and a spiral heat exchanger, and the filtrate and the tower bottom liquid are respectively arranged at two sides of the heat exchanger.
The resource process of the ammonium sulfate wastewater containing heavy metal magnesium comprises the following steps:
1) reacting heavy metal magnesium-containing ammonium sulfate wastewater (which is acidic) in a first reaction device 3, adding 10-50% calcium hydroxide slurry to control the pH value to be about 12, and then filtering by a first filtering device 4 to obtain a first filter cake and a first filtering liquid;
the pH value of the first filter cake is more than 12, and the first filter cake contains heavy metal, ammonia and magnesium hydroxide, which are dangerous wastes, so the first filter cake can be sold only after being purified and reaching the national standard;
the first filtrate contains free ammonia, small amount of calcium sulfate, calcium hydroxide, small amount of magnesium hydroxide, and small amount of heavy metal ammine complex ion, such as NI (NH3)6 2+、NI(NH3)4 2+、NI(NH3)2 2+。
2) The first filtrate and the fourth filtrate are mixed, preheated in a filtrate channel of a preheater 15 and then enter a stripping deamination device 16 for stripping deamination to obtain tower bottom liquid and ammonia vapor;
condensing the ammonia vapor to obtain ammonia water with the mass concentration of 20% for recycling;
the pH value of the tower bottom liquid is about 10-12.5, the tower bottom liquid enters a second heavy metal filtering device 17 for filtering after being preheated in a tower bottom liquid channel of a preheater 15, and a fifth filter cake and a fifth filtrate are obtained;
recovering the fifth filter cake as heavy metal, and discharging the fifth filtrate after the fifth filtrate enters a wastewater pH adjusting device 18 and the pH is adjusted to 6-9 by adding sulfuric acid or hydrochloric acid;
discharged is wastewater for removing heavy metals and ammonia, wherein the wastewater contains a small amount of calcium sulfate, magnesium sulfate and wastewater containing part of soluble salts such as sodium chloride, sodium sulfate and the like.
3) The first filter cake is crushed by a crusher or a ball mill and the like, then reacts with sulfuric acid with the mass concentration of 5-98% or hydrochloric acid with the mass concentration of 5-31% in a second reaction device 5, the pH is controlled to be 3-6, and after the heavy metal, magnesium, ammonia and excessive calcium hydroxide in the first filter cake react with acid, soluble heavy metal sulfate, magnesium sulfate, ammonium sulfate and insoluble solid calcium sulfate dihydrate are formed;
then filtering through a second filtering device 7 to obtain a second filter cake and second filtrate;
the main component of the second filter cake is calcium sulfate dihydrate, which meets the national standard requirement, and gypsum is manufactured by selling or drying treatment;
the second filtrate contains soluble salts such as heavy metal sulfate, magnesium sulfate, ammonium sulfate and the like;
4) adding liquid alkali or sodium carbonate into the second filtrate in a first pH adjusting device 9 to adjust the pH to 8-9.5, forming precipitates of most heavy metals, and then filtering the precipitates by a first heavy metal filtering device 11 to obtain a third filter cake and a third filtrate;
the third filter cake is heavy metal and is recycled together with the deaminated heavy metal;
5) adding liquid caustic soda or sodium carbonate into the third filtrate in a second pH adjusting device 12 to adjust the pH to 11-12.5, forming a precipitate by magnesium sulfate, and then filtering the precipitate by a magnesium hydroxide filtering device 13 to obtain a fourth filter cake and a fourth filtrate;
the main component of the fourth filter cake is magnesium hydroxide, and the magnesium hydroxide is subjected to selling treatment or drying pyrolysis to prepare magnesium oxide;
the fourth filtrate is ammonia-containing wastewater containing a small amount of sodium hydroxide, magnesium hydroxide, calcium sulfate and the like, and is mixed with the first filtrate before being added into the preheater 15.
The liquid caustic soda or the sodium carbonate is respectively added into the two filtrates, and the functions are respectively as follows: adding liquid alkali or sodium carbonate solution to precipitate heavy metal hydroxide or carbonate, filtering, and adding liquid alkali or sodium carbonate solution to precipitate magnesium sulfate into magnesium hydroxide or magnesium carbonate.
Finally, it is also noted that the above-mentioned lists merely illustrate a few specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.
Claims (10)
1. A comprehensive utilization and resource treatment process for heavy metal-containing ammonium sulfate wastewater is characterized in that: the method comprises the following steps:
firstly, reacting ammonium sulfate wastewater containing heavy metals with calcium hydroxide, and controlling the pH value of the reaction to be between 11 and 12; then filtering to obtain a calcium sulfate dihydrate filter cake containing heavy metal hydroxide and filtrate;
step two, the filtrate obtained in the step one and the filtrate obtained in the step four are subjected to stripping deamination;
step three, crushing the calcium sulfate dihydrate filter cake obtained in the step one, carrying out solid-liquid mixing reaction on the crushed calcium sulfate dihydrate filter cake and sulfuric acid or hydrochloric acid, and filtering to obtain a calcium sulfate dihydrate filter cake and a filtrate which meet the national standard;
adding liquid caustic soda or calcium hydroxide into the filtrate obtained in the step three, controlling the pH value to 8-9.5, and then filtering; if there is magnesium sulfate in the waste water, liquid alkali or calcium hydroxide is added to settle magnesium hydroxide, and the filtered liquid is stripped to deaminize.
2. The comprehensive utilization and resource treatment process of the wastewater containing the heavy metal ammonium sulfate according to claim 1, which is characterized in that:
the first step comprises the following steps:
reacting the heavy metal magnesium-containing ammonium sulfate wastewater with the fourth filtrate in a first reaction device (3), adding 10-50% calcium hydroxide slurry to control the pH value to be 12, and then filtering by a first filtering device (4) to obtain a first filter cake and a first filtrate;
the first filter cake is a calcium sulfate dihydrate filter cake containing heavy metal hydroxides, and the first filtrate is the filtrate obtained in the first step.
3. The comprehensive utilization and resource treatment process of the wastewater containing the heavy metal ammonium sulfate according to claim 2, which is characterized in that:
the second step comprises the following steps:
mixing the filtrate obtained in the first step with the filtrate obtained in the fourth step, preheating the mixture in a filtrate channel of a preheater (15), and then feeding the mixture into a stripping deamination device (16) for stripping deamination to obtain tower bottom liquid and ammonia steam;
condensing the ammonia vapor to obtain ammonia water with the mass concentration of 20% for recycling;
the tower bottom liquid is sent to a preheater (15) to preheat the filtrate, and then is filtered in a second heavy metal filtering device (17) to obtain a fifth filter cake and a fifth filtrate;
and recovering the fifth filter cake as heavy metal, and feeding the fifth filtrate into a wastewater pH adjusting device (18) to adjust the pH to 6-9 by adding sulfuric acid or hydrochloric acid, and discharging the fifth filtrate after reaching the standard.
4. The comprehensive utilization and resource treatment process of the wastewater containing the heavy metal ammonium sulfate according to claim 3, which is characterized in that:
the third step comprises:
crushing the first filter cake by using a crusher or a ball mill and the like, then reacting the crushed first filter cake with sulfuric acid with the mass concentration of 5-98% or hydrochloric acid with the mass concentration of 5-31% in a second reaction device (5), controlling the pH to be 3-6, and reacting heavy metal, magnesium, ammonia and excessive calcium hydroxide in the first filter cake with acid to form soluble heavy metal sulfate, magnesium sulfate, ammonium sulfate and insoluble solid calcium sulfate dihydrate;
then filtering through a second filtering device (7) to obtain a second filter cake and second filtrate;
taking the second filtrate as filtrate obtained in the third step;
the main component of the second filter cake is calcium sulfate dihydrate, which meets the national standard requirement, and gypsum is prepared by selling or drying;
the fourth step comprises the following steps:
adding liquid alkali or sodium carbonate into the second filtrate in a first pH adjusting device (9) to adjust the pH to 8-9.5, forming precipitates of most heavy metals, and then filtering by a first heavy metal filtering device (11) to obtain a third filter cake and a third filtrate;
the third filter cake is heavy metal and is recycled together with the deaminated heavy metal;
adding liquid caustic soda or sodium carbonate into the third filtrate in a second pH adjusting device (12) to adjust the pH to 11-12.5, forming a precipitate by magnesium sulfate, and then filtering by a magnesium hydroxide filtering device (13) to obtain a fourth filter cake and a fourth filtrate;
the fourth filter cake is subjected to selling treatment or drying pyrolysis to prepare magnesium oxide;
the fourth filtrate is ammonia-containing wastewater, wherein a small amount of sodium hydroxide, magnesium hydroxide, calcium sulfate and other substances are contained in the ammonia-containing wastewater, and the fourth filtrate is mixed with the first filtrate before being added into the preheater (15);
and taking the fourth filtrate as the filtrate obtained in the fourth step.
5. The comprehensive utilization and resource treatment process of the wastewater containing the heavy metal ammonium sulfate according to claim 4, which is characterized in that:
adding 10-50% calcium hydroxide slurry in the step 1) to react, and controlling the pH value at 12.
6. The purification process of calcium hydroxide for treating ammonium sulfate wastewater containing heavy metals and by-product calcium sulfate according to claim 5, which is characterized in that:
the pH of the bottom liquid is 10-12.5.
7. The purification process of calcium hydroxide for treating ammonium sulfate wastewater containing heavy metals and by-product calcium sulfate according to claim 6, which is characterized in that:
discharged is wastewater for removing heavy metals and ammonia, wherein the wastewater contains a small amount of calcium sulfate, magnesium sulfate and wastewater containing part of soluble salts such as sodium chloride, sodium sulfate and the like.
8. The device for purifying the ammonium sulfate wastewater containing the heavy metals and the byproduct calcium sulfate by using the calcium hydroxide, which is applied to the purification process of treating the ammonium sulfate wastewater containing the heavy metals and the byproduct calcium sulfate by using the calcium hydroxide as claimed in any one of claims 1 to 7, is characterized in that:
comprises a first reaction device (3), a first filtering device (4), a second reaction device (5), a second filtering device (7), a first pH adjusting device (9), a first heavy metal filtering device (11), a second pH adjusting device (12), a magnesium hydroxide filtering device (13), a preheater (15), a stripping deamination device (16), a second heavy metal filtering device (17), a wastewater pH adjusting device (18), a sulfuric acid storage tank (6), a lime slurry storage tank (2), an ammonium sulfate wastewater storage tank (1) and an alkali solution storage tank (10);
the lime slurry storage tank (2) and the ammonium sulfate wastewater storage tank (1) are both connected with the inlet of the first reaction device (3);
the outlet of the first reaction device (3) is connected with the inlet of the first filtering device (4);
a filter residue outlet of the first filtering device (4) is connected with an inlet of the second reaction device (5), and a filtrate outlet of the first filtering device (4) is connected with an inlet of a filtrate channel of the preheater (15);
the outlet of the filtrate channel of the preheater (15) is connected with the inlet of a stripping deamination device (16);
the sulfuric acid storage tank (6) is connected with an inlet of the second reaction device (5);
the outlet of the second reaction device (5) is connected with the inlet of a second filtering device (7);
the filter residue at the filter residue outlet of the second filtering device (7) is a calcium sulfate dihydrate filter cake, and the calcium sulfate dihydrate filter cake is sold or dried; the filtrate outlet of the second filtering device (7) is connected with the inlet of the first pH adjusting device (9);
the outlet of the alkali solution storage tank (10) is respectively connected with the inlet of the first pH adjusting device (9) and the inlet of the second pH adjusting device (12);
the outlet of the first pH adjusting device (9) is connected with the inlet of a first heavy metal filtering device (11);
the filtrate outlet of the first heavy metal filtering device (11) is connected with the inlet of a second pH adjusting device (12);
the outlet of the second pH adjusting device (12) is connected with the inlet of the magnesium hydroxide filtering device (13);
the filtrate outlet of the magnesium hydroxide filtering device (13) is connected with the inlet of a filtrate channel of the preheater (15);
the outlet at the bottom of the stripping deamination device (16) is connected with the inlet of a second heavy metal filtering device (17) after passing through a tower bottom liquid channel of a preheater (15);
and a filtrate outlet of the second heavy metal filtering device (17) is connected with an inlet of a wastewater pH adjusting device (18).
9. The apparatus according to claim 8, wherein the apparatus for treating the ammonium sulfate wastewater containing heavy metals and purifying the calcium sulfate byproduct comprises:
the first filtering device (4), the second filtering device (7), the first heavy metal filtering device (11) and the magnesium hydroxide filtering device (13) can be one or more of a plate-and-frame filter press, a disc vacuum filter, a vacuum belt filter or a centrifugal machine and are used for filtering slurry;
the first reaction device (3), the second reaction device (5), the first pH adjusting device (9), the second pH adjusting device (12) and the wastewater pH adjusting device (18) are all used for adjusting the pH value;
the preheater (15) is used for preheating the solution;
the stripping deamination device (16) is used for carrying out stripping deamination treatment on the ammonia-containing wastewater, the ammonia content of the deaminated wastewater is less than 10mg/L, and 20% ammonia water is recovered;
the sulfuric acid storage tank (6) is used for storing sulfuric acid solution with mass concentration of 5-98% or hydrochloric acid with mass concentration of 5-31%;
the lime slurry storage tank (2) is used for storing 10-50% of lime slurry;
the ammonium sulfate waste water storage tank (1) is used for storing ammonium sulfate waste water containing heavy metals to be treated;
the alkali solution storage tank (10) is used for storing liquid alkali or sodium carbonate solution.
10. The apparatus for treating ammonium sulfate wastewater containing heavy metals and purifying calcium sulfate byproduct using calcium hydroxide according to claim 9, wherein:
the preheater (15) is one of a tube heat exchanger, a plate heat exchanger or a spiral heat exchanger, and the filtrate and the tower bottom liquid are respectively arranged at two sides of the heat exchanger.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114058848A (en) * | 2021-10-09 | 2022-02-18 | 杭州逐真科技有限公司 | System and process for recovering copper, nickel, zinc, chromium and iron from electroplating sludge or other multi-metal mixture |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5120447A (en) * | 1991-03-06 | 1992-06-09 | Gte Products Corporation | Method for removing heavy metals from wastewater |
| CN103553138A (en) * | 2013-11-01 | 2014-02-05 | 王文领 | Comprehensive utilization method for separating, concentrating and purifying manganese sulfate, magnesium sulfate and calcium sulfate in high-salt waste water |
| CN106396163A (en) * | 2015-08-12 | 2017-02-15 | 江苏沃德凯环保科技有限公司 | Method for comprehensive treatment and recycling of ammonium sulfate wastewater of rare-earth smelting |
| CN107473447A (en) * | 2017-09-26 | 2017-12-15 | 赣州逸豪优美科实业有限公司 | A kind of method of calcium method recycling treatment acidic high-strength ammonium sulfate waste water |
| CN110732543A (en) * | 2018-10-18 | 2020-01-31 | 庞炼红 | Method for jointly producing cement clinker and ammonia water by electrolyzing metal manganese waste residue and gypsum |
-
2020
- 2020-08-18 CN CN202010829501.6A patent/CN112047548A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5120447A (en) * | 1991-03-06 | 1992-06-09 | Gte Products Corporation | Method for removing heavy metals from wastewater |
| CN103553138A (en) * | 2013-11-01 | 2014-02-05 | 王文领 | Comprehensive utilization method for separating, concentrating and purifying manganese sulfate, magnesium sulfate and calcium sulfate in high-salt waste water |
| CN106396163A (en) * | 2015-08-12 | 2017-02-15 | 江苏沃德凯环保科技有限公司 | Method for comprehensive treatment and recycling of ammonium sulfate wastewater of rare-earth smelting |
| CN107473447A (en) * | 2017-09-26 | 2017-12-15 | 赣州逸豪优美科实业有限公司 | A kind of method of calcium method recycling treatment acidic high-strength ammonium sulfate waste water |
| CN110732543A (en) * | 2018-10-18 | 2020-01-31 | 庞炼红 | Method for jointly producing cement clinker and ammonia water by electrolyzing metal manganese waste residue and gypsum |
Non-Patent Citations (1)
| Title |
|---|
| 赵云龙: "《建筑石膏生产与应用技术》", 中国建材工业出版社, pages: 25 - 27 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114058848A (en) * | 2021-10-09 | 2022-02-18 | 杭州逐真科技有限公司 | System and process for recovering copper, nickel, zinc, chromium and iron from electroplating sludge or other multi-metal mixture |
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