KR102364374B1 - Recycling Method for Copper Sulfate Waste Liquid Generated during Build-Up Process and Agricultural Copper Sulfate Fertilizer produced by the Recycling Method - Google Patents

Abstract

The present invention relates to a method for recycling copper sulfate waste generated in the build-up manufacturing process and agricultural copper sulfate fertilizer produced therefrom, and more particularly, to remove impurities contained in copper sulfate waste generated in the build-up manufacturing process, and evaporate It relates to a method for obtaining high-purity and high-concentration copper sulfate through a concentration process and filtration and dehydration and using it as an agricultural copper sulfate fertilizer.
The recycling method of copper sulfate waste generated in the build-up manufacturing process according to the present invention includes an impurity removal step (S100) of removing impurities contained in the copper sulfate waste; It includes an evaporation-concentration step (S200) of preparing the formed evaporated concentrate; and a filtering and dehydration step (S300) of filtering and dehydrating the evaporated concentrate to precipitate copper sulfate crystals.

Description

Recycling Method for Copper Sulfate Waste Liquid Generated during Build-Up Process and Agricultural Copper Sulfate Fertilizer produced by the Recycling Method

The present invention relates to a method for recycling copper sulfate waste generated in the build-up manufacturing process and to an agricultural copper sulfate fertilizer produced therefrom, and more particularly, to remove impurities contained in copper sulfate waste generated in the build-up manufacturing process, and evaporate It relates to a method for obtaining high-purity and high-concentration copper sulfate through a concentration process and filtration and dehydration and using it as an agricultural copper sulfate fertilizer.

Printed Circuit Board (PCB) is a core component of electronic devices, and is manufactured by a Build-Up process in which conductor layers and insulating layers are sequentially stacked by plating, printing, etc.

In the build-up process, a surface etching process and a water washing process are necessarily accompanied by using an acid such as sulfuric acid, and copper sulfate waste liquid is generated in this process. As it has a very harmful effect on the environment, it must be discharged after going through a treatment process that removes harmful substances such as heavy metals.

As a technology for recycling and processing conventional copper sulfate wastes, in Korean Patent Registration No. 10-1386701, a treatment solution containing a thiosulfate compound by mixing an electroless plating waste solution or a concentrated solution thereof, an exclusive treatment solution containing copper, and sulfuric acid A method for recovering high-purity copper from an electroless plating waste solution for recovering metallic copper from the treatment solution by using electrolysis after manufacturing is presented.

In addition, in Korea Patent No. 10-1965748, after crushing the waste ABS resin plated with chromium, nickel and copper, immersing it in a dilute sulfuric acid solution to dissolve nickel and copper, and applying physical stirring and ultrasonic waves to the plated chrome particles A method for recycling waste ABS resin plated with chromium, nickel and copper including a peeling process is presented.

On the other hand, copper sulfate is also related to the metabolism of crops and the action of chlorophyll, so when copper sulfate is deficient, leaves are discolored and twisted, and shoot growth is inhibited, and necrotic lesions occur in leaf veins or flowers do not bloom. In addition, most of the soils lacking copper sulfate have a low pH, which in turn causes absorption and deficiency of other components such as phosphoric acid and boron.

The present invention is a part of research to obtain copper sulfate from copper sulfate-containing waste generated in the build-up manufacturing process and use it as agricultural fertilizer under optimal conditions to remove impurities such as heavy metals from copper sulfate waste under optimal conditions and evaporate it to obtain high purity and high concentration It was confirmed that copper sulfate can be obtained, leading to the present invention.

Domestic Registered Patent No. 10-1386701 Domestic Registered Patent No. 10-1965748

An object of the present invention to solve the above problems is to remove impurities of copper sulfate waste generated in the build-up manufacturing process and to obtain high-purity and high-concentration copper sulfate through an evaporation concentration process and a filtration and dehydration process to utilize it as an agricultural copper sulfate fertilizer. to provide a way for

The recycling method of copper sulfate waste generated in the build-up manufacturing process of the present invention for solving the above problems is an impurity removal step (S100) of removing impurities contained in the copper sulfate waste; and feeding the copper sulfate waste from which impurities are removed to an evaporator. It includes an evaporation concentration step (S200) of preparing an evaporation concentrate in which granules are formed by evaporation while concentrating; and a filtering and dehydration step (S300) of filtering and dehydrating the evaporation concentrate to precipitate copper sulfate crystals.

The impurity removal step (S100) is characterized in that the impurities are removed using any one of pH control, solvent extraction, and a combination thereof.

In the impurity removal step (S100), the pH is controlled to 2 to 5.

The solvent extraction method of the impurity removal step (S100) is characterized in that any one of a phosphoric acid solvent, a trialkylphosphine solvent, an oxime solvent, and a combination thereof is used.

The solvent extraction method in the impurity removal step (S100) is characterized in that it uses a continuous solvent extraction method.

The evaporation and concentration step (S200) is characterized in that the evaporation concentration while raising the temperature stepwise from 40 to 100 ℃.

As described above, according to the recycling method of copper sulfate waste generated in the build-up manufacturing process according to the present invention, impurities in the copper sulfate waste generated in the build-up manufacturing process are removed and high-purity and high-concentration processes are performed through evaporation and dehydration and filtration. It has the effect of recycling copper sulfate by obtaining copper sulfate and using it as agricultural fertilizer.

1 is a flow chart showing a recycling method of copper sulfate waste generated in the build-up manufacturing process according to the present invention.
2 is a process diagram of a continuous solvent extraction system according to an embodiment of the present invention.
3 is a copper sulfate crystal according to the crystallization conditions according to an embodiment of the present invention, (A) is a copper sulfate crystal under room temperature conditions, (B) is a photograph of copper sulfate crystals under a high temperature condition.
Figure 4 is a process flow chart of a copper sulfate pilot system according to an embodiment of the present invention.

Specific features and advantages of the present invention will be described in detail below with reference to the accompanying drawings. Prior to this, when it is determined that a detailed description of a function and a configuration related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted.

The present invention relates to a method for recycling copper sulfate waste generated in the build-up manufacturing process and to an agricultural copper sulfate fertilizer produced therefrom, and more particularly, to remove impurities contained in copper sulfate waste generated in the build-up manufacturing process, and evaporate It relates to a method for obtaining high-purity and high-concentration copper sulfate through a concentration process and filtration and dehydration and using it as an agricultural copper sulfate fertilizer.

1 is a flowchart showing a recycling method of copper sulfate waste generated in a build-up manufacturing process according to the present invention.

The recycling method of copper sulfate waste generated in the build-up manufacturing process according to the present invention includes an impurity removal step (S100) of removing impurities contained in the copper sulfate waste and evaporative concentration while feeding the copper sulfate waste from which impurities have been removed to an evaporator to obtain granules. It includes an evaporation-concentration step (S200) of preparing the formed evaporated concentrate, and a filtration and dehydration step (S300) of filtering and dehydrating the evaporated concentrate to precipitate copper sulfate crystals.

In the impurity removal step ( S100 ), heavy metals and impurities contained in the copper sulfate waste are removed, and impurities such as cadmium, lead, chromium, nickel, and zinc may be removed except for copper.

In the impurity removal step (S100), impurities contained in the copper sulfate waste may be removed using any one of pH control, solvent extraction, adsorption removal using a surfactant, and a combination thereof.

The impurity removal step (S100-A) according to the first embodiment is to first remove impurities through pH control, and secondly to remove impurities and separate copper through solvent extraction. Impurities other than copper through pH control can be controlled by precipitation and filtration, where the pH is controlled to 2 to 5. If the pH is less than 2, it is difficult to precipitate impurities. Therefore, it is preferable not to deviate from the above pH range.

The pH control may be controlled using an alkali solution, and the type of the alkali solution is not limited as long as it has alkalinity, but specific examples include sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium hydrogen carbonate, and combinations thereof. Any one may be used, and the alkali solution may have a concentration of 0.1 to 2M.

For the solvent extraction method, any one of a phosphoric acid-based solvent, a trialkylphosphine-based solvent, an oxime-based solvent, and a combination thereof may be used.

More specifically, as a phosphoric acid-based solvent, D2EHPA (di(2-ethylhexyl)phosphate acid) of SYTEK, USA, Cyanex 932 (Trialkylphosohine oxide) of SYTEK, an oxime-based solvent as a trialkylphosphine-based solvent As the solvent, Lix 973 (5-dodecyl-salicylad oxime) manufactured by Henkel, Germany, may be used, but is not limited thereto. Preferably, a phosphoric acid solvent, D2EHPA (di(2-ethylhexyl)phosphate acid) may be used.

Prior to extracting Cu using a solvent extractant, the pH of the copper sulfate waste liquid from which impurities are removed may be controlled to 1 to 2 in order to improve the solvent extraction efficiency.

In addition, in order to improve the solvent extraction efficiency, the copper sulfate waste liquid and the solvent extractant may be mixed in a volume ratio of 1-2: 1.

When the solvent extraction method is used, the purity and yield content of copper sulfate can be improved by using the continuous solvent extraction method.

The continuous solvent extraction method is performed using a continuous solvent extraction device, which is separated from the first separation tank, the second separation tank, and the first separation tank for mixing and reacting the solvent for solvent extraction and the copper sulfate waste The first aqueous phase storage tank in which the dried aqueous phase is stored, the second aqueous phase storage tank in which the aqueous phase separated from the second separation tank is stored, the organic phase storage tank that stores the organic phase separated in the first and second separation tanks, and the separated organic phase and the stripping solution. and a stripping tank for separating copper sulfate by mixing and reacting. At this time, the stripping solution is not limited as long as it is for separating copper and copper compounds, but preferably, a sulfuric acid aqueous solution may be used.

In the solvent extraction method using a continuous solvent extraction device, a solvent for solvent extraction and copper sulfate waste are mixed and reacted in a first separation tank to separate a first aqueous phase and a first organic phase, and the first aqueous phase is transferred to the first aqueous phase storage tank, and the first The first solvent extraction step of transferring the organic phase to the organic phase storage tank and the mixing and reaction of the solvent for solvent extraction and the first aqueous phase in the second separation tank to separate the second aqueous phase and the second organic phase, and transfer the second aqueous phase to the second aqueous phase storage tank and a second solvent extraction step of transferring the second organic phase to an organic phase storage tank, and a stripping step for obtaining copper sulfate by mixing and reacting the first organic phase and the second organic phase with a stripping solution in the stripping tank.

As an example, it has been described that the first and second solvent extraction steps are performed, but it is not limited thereto, and the solvent extraction process may be performed n-th, and the organic phase containing copper is to be obtained as copper sulfate through scrubbing and back extraction. can

Preferably, by adjusting the pH of the copper sulfate waste input to the solvent extraction device to 1 to 3 and then solvent extraction, it is possible to improve the separation of impurities and the extraction rate of copper.

In the impurity removal step (S100-B) according to the second embodiment, impurities are firstly removed through pH control, and impurities are removed by secondly filtering the precipitate after cooling and precipitation to form an agglomerate to which impurities are adsorbed using a surfactant. removed, and the remaining impurities may be removed and copper may be separated through a third solvent extraction method.

In the case of the removal of impurities through the first pH control and the removal of impurities using the third solvent extraction method, the same as described above, a description thereof will be omitted.

In the adsorption removal using a surfactant, the precipitate containing impurities is removed through the primary pH control, and a surfactant is added to the remaining filtrate to form an aggregate in which heavy metal is adsorbed to the micelles, and the aggregate is cooled and precipitated to remove the precipitate By filtration, heavy metals and impurities other than Cu can be removed.

At this time, as the surfactant, any one of anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and combinations thereof may be used, but more preferably, the heavy metal component of the cation effectively by electrostatic attraction Anionic surfactants that can easily adsorb and form aggregates can be used for precipitation separation.

The anionic surfactant may be selected from any one of carboxylic acid salts (RCOO ^- M ⁺ ), sulfonic acid salts (RSO3 ^- M ⁺ ), sulfuric acid ester salts (ROSO3 ^- M ⁺ ), phosphoric acid ester salts (RPO3 ^- Na2 ⁺ ), and combinations thereof. may be selected, and specific examples include sodium dodecyl sulfate (SDS), ammonium lauryl sulfate (ALS), sodium lauryl ethylene sulfate (SLES), and linear alkylbenzene. Linear Alkylbenzene Sulfonate (LAS), Alpha-Olefin Sulfonate (AOS) Alkyl Sulfate (AS), Alkyl Ether Sulfate (AES), Sodium Alkane Sulfonate (AES) Sulfonate; SAS) and any one of combinations thereof, but is not limited thereto. More preferably, sodium dodecyl sulfate (Sodium Dodecyl Sulfate; SDS) may be used.

The addition amount of the surfactant is added to have a S/M (surfactant/metal) molar ratio of 6 to 10: 1, and if the amount of the surfactant is less than the above range (if it is added less), it is difficult to obtain adsorption and separation of heavy metals, If it exceeds (if a lot is added), it is preferable not to deviate from the above range in terms of process efficiency because the effect of adsorption and separation of heavy metals according to the content increase is insignificant.

At this time, the sludge was first filtered while maintaining pH 6 to 8 while reacting with the surfactant and injecting sodium hydroxide, and the filtrate was cooled at 3 to 5 ° C. for 3 to 6 hours to cool and precipitate the aggregates adsorbed with heavy metals. then filtered.

The surfactant may be carried out for 6 hours to 15 hours from the time of input to the filtration separation of the aggregates, and more preferably, the initial input of the total reaction time (20% of the total reaction time from the start) is 150 at 30 to 35 ° C. The surfactant is uniformly dispersed in the filtrate by stirring at 300 rpm, and the impurity sludge is first filtered while maintaining pH 6 to 8 while injecting sodium hydroxide, and stirring is stopped until the total reaction time exceeds 20% to 50% , by standing at room temperature (20 to 25 ° C.), the heavy metal component is stably adsorbed to the micelles of the surfactant and has a time to form an aggregate, and from 3 to 5 ° C. The agglomerates are cooled and precipitated. Preferably, the cooling precipitation process may be performed for 3 to 6 hours.

Aggregates containing heavy metals contain heavy metals such as Pd, Fe, and Cd except Cu. Dissolve and wash in a solvent, or use solid-liquid separation and ion exchange resin to separate the heavy metals and extract specific heavy metals to be recycled as resources. can

In the evaporative concentration step (S200), the copper sulfate waste from which impurities have been removed and the solvent-extracted copper sulfate aqueous solution (hereinafter, copper sulfate aqueous solution) are fed 1 to 10 times in the evaporative concentrator to evaporate and concentrate to produce granules. do.

At this time, evaporation and concentration may be performed for 30 minutes to 10 hours, and may be performed at 40°C to 100°C. More preferably, copper sulfate waste granules can be formed while the temperature is raised stepwise from 40°C to 100°C. At this time, when the temperature rises to the boiling point, the temperature is gradually increased to 0.1 to 2 °C/min, or by 3 to 10 °C at intervals of 5 to 30 minutes to a copper sulfate concentration of 230,000 to 260,000 ppm at which copper sulfate crystals begin to form. An evaporative concentration process may be performed.

At this time, the copper sulfate aqueous solution is not supplied singly in the evaporator, but is supplied in multiple stages 2 to 10 times, and when the multistage supply is performed, the pH gradient, the concentration gradient, and combinations thereof are calculated to determine whether the copper sulfate aqueous solution is supplied and the supply amount. To this end, it may further include a pH measuring means for measuring the pH of the aqueous copper sulfate solution inside the evaporator and a concentration measuring means for measuring the concentration of copper sulfate.

More specifically, as the copper sulfate waste contained in the evaporator and the copper sulfate in the aqueous solution are concentrated during evaporative concentration, the concentration of copper sulfate increases and the pH in the evaporator decreases. When evaporative concentration proceeds with a gradient and a concentration gradient, but the content of the concentrated copper sulfate is small, the pH gradient and the concentration gradient are out of the above ranges.

As a specific example, the copper sulfate concentration in the copper sulfate aqueous solution should be increased by 5,000 to 6,000 ppm/hr during evaporation and concentration, but when it is measured to be less than 5000 ppm/hr, the copper sulfate aqueous solution is additionally supplied, and at this time, the concentration gradient or group calculated after the initial input It is also possible to control the supply amount by calculating the difference from the set concentration gradient value.

By supplying an aqueous solution of copper sulfate according to the pH and concentration of the aqueous solution of copper sulfate in the evaporator rather than evaporating and concentrating the aqueous solution of copper sulfate through a single supply, the production volume is 1.5 to 3 times compared to the time, and there is an advantage that the enlargement of the evaporator is not required.

In the filtration and dehydration step (S300), The evaporated concentrate is filtered and dehydrated to precipitate copper sulfate crystals.

For filtration and dehydration, a filter press may be used, and if the purpose is for filtration and dehydration, the present invention is not limited thereto. The filter press is performed under a filter cloth size of 50 to 200 mesh and a pressure of 1 to 15 kgf/cm 2 , and filtration and dehydration efficiency is excellent under the filter cloth size and pressure conditions.

Copper sulfate powder obtained from copper sulfate waste generated in the buildup manufacturing process according to the present invention is obtained by the above-described recycling method, and the copper sulfate powder is copper sulfate pentahydrate (CuSO ₄ ·5H ₂ O) having a purity of 98 to 99%. It contains about 23 to 26%, and contains heavy metals within the allowable standards for heavy metals in fertilizers, so it is suitable for use as agricultural fertilizers.

Hereinafter, the present invention will be described in detail below with reference to a preferred embodiment. However, the following examples are intended to specifically illustrate the present invention, and are not limited thereto.

1. Copper sulfate waste component analysis

The raw materials were supplied with build-up waste from build-up manufacturers in Gumi and Gyeongbuk.

Ion Chromatography (IC) to measure the content of sulfuric acid, hydrochloric acid, and nitric acid and ICP-OES (Inductively Coupled Plasma) were measured for elemental analysis of 25 items. Table 1 below shows IC measurement values, Table 2 shows ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer) measurement value is shown.

Analysis of inorganic substances in raw materials through ICP-OES A sample of 15±0.2 g was taken, reacted in 6 mL of nitric acid for 12 hours, and then 2 mL of hydrogen peroxide was added and acid-decomposed with a microwave (Ethos1, Milestone, Italy). Component content was measured using a spectrometer (OPTIMA 5300 DV, Perkin-Elmer, USA), and the device conditions are shown in Table 3.

There was a raw material containing acids other than sulfuric acid in the copper sulfate waste liquid (Table 1), and it was considered desirable to select a raw material that did not contain other acids even if the copper content was low. In particular, since hydrochloric acid can be fatal to crops, it was determined that it would be preferable to remove hydrochloric acid through a separate process or use a sample that does not contain hydrochloric acid from copper sulfate waste liquid containing hydrochloric acid.

Copper sulfate waste liquid contains impurities and heavy metals Cd, Pb, As, Cr, Ni, Zn, etc. in addition to copper components (Table 2), and technology to remove heavy metals is required for use as a fertilizer raw material. Although the content of heavy metals in the copper sulfate waste liquid is lower than the standard for fertilizer raw materials, it is thought that the content will increase as the raw materials are concentrated and processed.

2. Removal of heavy metals

2-1. Heavy metal removal condition setting by pH adjustment

Raw materials C and D, excluding those containing hydrochloric acid among the supplied raw materials, were mixed in a weight ratio of 1:1 and used as raw materials. The pH of the raw material was 1.2, and the content analysis according to pH was analyzed through ICP-OES (Table 4).

As the pH increased, impurity heavy metals were bound and started to precipitate, but copper also showed a tendency to decrease. From pH 2 to pH 5, the copper content was gradually decreased by about 25% compared to before the reaction, but at pH 6, the copper content was abruptly decreased, so it was determined that it would be preferable to control the pH to pH 2 to 5.

2-2. Removal of heavy metals using solvent extraction

2-2-1. Extraction of Cu according to pH control

In order to confirm the effect of removing impurities according to solvent extraction, a continuous solvent extraction apparatus was designed as shown in FIG. 2 . At this time, a stirring tank having an effective volume of 5.2L of an overhead stirring method was prepared, and a separation tank having an effective volume of 10L was prepared.

Solvent extractant D2EPHA was prepared, and solvent extract was prepared by mixing 20 vol% of solvent extractant and 80 vol% of diluent kerosene. In order to check the extraction content of Cu according to the pH adjustment of the copper sulfate solution, the aqueous phase and the organic phase were mixed in a volume ratio of 1:1 under pH 0.5, 1 and 2. The stirring speed was performed at 500 rpm in the stirring tank, and the residence time was 30 minutes in the separation tank and 65 minutes in the separation tank.

As the pH increased, Cu was precipitated by 1.2 to 2.0%, and impurities such as Fe and Al were not precipitated. In particular, at pH 1, Cu was 18.6%, indicating a high extraction rate.

Through this, it was confirmed that the pH affects the extraction rate during extraction of Cu through solvent extraction, and it was determined that the pH is preferably controlled to be 0.5 to 2, and more preferably controlled to pH 1.

2-2-2. Removal of heavy metals according to the type and mixing ratio of the solvent extractant

The optimal conditions were searched for by confirming the ability to remove heavy metals according to the solvent extractant type and mixing ratio.

Cyanex272, D2EHPA, Lix-841, and PC-88A were selected as solvent extractors, and heavy metals Fe, Zn, Cd, Pb, and Al were selected as removal targets. Additionally, it was confirmed whether Cu was removed during solvent extraction.

3 shows the impurity removal ability according to the type and mixing ratio of the solvent extractant, (A) shows the heavy metal removal efficiency according to the type of the solvent extractant, and (B) shows the heavy metal removal efficiency according to the solvent extractant ratio.

As a result of checking the removal conditions for each of the four solvents, D2EHPA and Cyanex-923 showed more than about 80% removal efficiency, but Lix-841 and PC-88A solvents showed less than about 50% efficiency. On the other hand, in the case of Cu, a decrease of 5~15% was shown in all solvents, but Cu loss was measured to be low in D2EHPA and Cyanex-923. In particular, in D2EHPA, the removal efficiency for Fe, Zn and Al was 96.01% , 99.9%, and 86.7%, and for Cd and Pb, 71.9% and 61.7%, showing excellent heavy metal removal efficiency. In order to confirm the optimal extraction ratio of raw material and solvent, extraction by ratio was analyzed and there was no significant difference. Therefore, it is considered that it is most efficient to remove impurities by selecting solvent D2EHPA and Cyanex-923 through this experiment and setting the ratio to 1:1.

2-2-3. Removal of heavy metals according to the concentration of the solvent extractant

As a result of evaluating the impurity removal efficiency by concentration of the selected D2EHPA and Cyanex-923, D2EHPA showed more than 80% efficiency at 0.7 M concentration. Considering the efficiency and efficiency, the final concentration of 0.7 M was selected.

Cyanex-923 solvent showed about 85% efficiency at a concentration of 0.5 M, and when it exceeded 0.5 M, it was confirmed that the impurity efficiency was slightly decreased.

Through an experiment on the heavy metal removal ability according to the concentration of the solvent extractant, it was confirmed that the concentration of the solvent extractant affects the heavy metal removal ability, and the heavy metal removal efficiency can be maximized by using the solvent extractant of an appropriate concentration. A 1:1 ratio of 0.7 M D2EHPA and 0.5 M Cyanex-923 was considered to be the most effective, and when the impurity removal criteria were satisfied, it was judged that it was possible to lower the solvent concentration in consideration of economic feasibility.

3. Copper Sulfate Crystallization

Concentrated and cooled to form copper sulfate crystals. A total of 1200 ml of copper sulfate solution was put into the concentrator in 200 ml, 500 ml, and 500 ml steps, and the temperature was raised from 40° C. to 70° C. by 5 to 10° C. for about 82 minutes each time the boiling point was reached (at intervals of about 10 to 20 minutes) for about 82 minutes. concentrated. At the time of concentration, it was confirmed that the Cu concentration in the copper sulfate solution was about 20-25 wt% (200,000-250,000 ppm), and fine crystals started to form from about 65 ° C. It was determined that it would be desirable to carry out the process.

4 shows copper sulfate crystals according to crystallization conditions, (A) shows copper sulfate crystals under room temperature conditions, and (B) shows copper sulfate crystals under high temperature conditions.

The copper content started to crystallize from about 25%, and the copper crystals were filtered and then solidified under the conditions of drying at room temperature (20±5° C.) and drying at high temperature (95±5° C.). As a result, it was determined that it would be preferable to form crystals by cooling and solidifying at room temperature because the copper sulfate color became pale under high-temperature drying conditions and loss due to combustion occurred.

4. Copper Sulfate Pilot System

After weighing the raw material, put it into the reactor, remove impurities first through pH adjustment, adjust the temperature of the evaporation and concentration reactor to 94±5 ℃ , and feed 5 times at 1 hour intervals. FIG. 5 is a copper sulfate pilot system process flowchart show

The evaporator is made of SUS304 material of 1500(W)×1500(H)×1500(D)mm, and the inside is designed with FRP coating to prevent corrosion. In this case, the power was 15 kW, and the heater was SUS 316 and Teflon coated.

The initial input amount was 2100ml (2399 kg), and after 1 hour of initial input, feeding was performed every hour for a total of 5 feedings, and the supply amount for each round is shown in Table 6 below. The transfer was performed using an Air Diaphragm pump, and filtration/dehydration was performed under a filter press of 2 m3/h, vacuum 60 psi, and 30 L/min, and it took about 1 hour for transfer and filtration/dehydration.

After filtration/dehydration, the final copper sulfate was recovered, and as a result of measuring the weight, it was confirmed that 102.5 kg/hr could be produced (Table 7).

In case of single supply of raw material, copper sulfate production per hour was about 53.4 kg/hr, while in case of multi-stage supply, it was 102.5 kg/hr. Through the above results, it was confirmed that the production efficiency of copper sulfate in the multi-stage supply is significantly superior to that in the single supply when the raw material is input to the evaporator.

5. Analysis result related to the fertilizer standards announced by the Rural Development Administration for copper sulfate

As a result of analyzing the prepared copper sulfate powder according to the quality inspection method of fertilizer notified by the Rural Development Administration to use it as a raw material for fertilizer, the water-soluble copper (%) content was 25.54%, which satisfies the standard value.

As a result of analyzing the fertilizer's heavy metal acceptance criteria, it was found that 6 types of heavy metals (As, Cd, Pb, Cr, Ni, Zn) contained heavy metals within the allowable range. As a result of analyzing the purity of copper sulfate pentahydrate (CuSO ₄ ·5H ₂ O), the purity was 98.2%.

heavy metal type Permissible amount of heavy metals in fertilizers (mg/kg) development results
(mg/kg) Arsenic (As) 50 N.D. Cadmium (Cd) 5 N.D. Lead (Pb) 150 22.4 Chromium (Cr) 300 N.D. Nickel (Ni) 50 N.D. Zinc (Zn) 900 123.0 N.D. = Not detected (0.1 mg/kg or less)

As described above, the present invention has been mainly described with reference to the accompanying drawings, but those of ordinary skill in the art to which the present invention pertains within the scope not departing from the technical spirit and scope described in the claims of the present invention Various modifications or variations of the present invention can be practiced. Accordingly, the scope of the present invention should be construed by the appended claims including examples of many such modifications.

Claims (8)

In the recycling method of copper sulfate waste generated in the build-up manufacturing process,
An impurity removal step of removing impurities contained in copper sulfate waste (S100); and
An evaporative concentration step (S200) of producing an evaporative concentrate with granules formed by evaporating and concentrating while feeding the copper sulfate waste from which impurities have been removed to the evaporative concentrator (S200); and
It includes a filtration and dehydration step (S300) of filtration and dehydration of the evaporated concentrate to precipitate copper sulfate crystals,
The impurity removal step (S100) is
The primary process of removing the precipitated impurities by controlling the pH to 2 to 5, the secondary process of removing the precipitated precipitate by adding a surfactant in a molar ratio of 6 to 10: 1 with the heavy metal, controlling the pH to 0.5 to 2 After that, the tertiary process of removing impurities and separating copper by continuous solvent extraction using a phosphoric acid-based solvent or a trialkylphosphine-based solvent is sequentially performed,
In the evaporation and concentration step (S200),
Concentrate by evaporating while raising the temperature stepwise from 40 to 100°C, and by calculating any one of the pH gradient in the evaporator, the concentration gradient of copper sulfate, or a combination thereof, the copper sulfate waste from which impurities have been removed is fed to the evaporator while controlling the supply amount characterized by
A method of recycling copper sulfate waste generated in the build-up manufacturing process.
delete delete delete delete delete The copper sulfate powder obtained by the recycling method of the copper sulfate waste generated in the build-up manufacturing process of claim 1.
An agricultural copper sulfate fertilizer comprising the copper sulfate powder of claim 7.

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