Photovoltaic industry quartz sand pickling wastewater reuse process: With the development of fiber optic communications, microelectronics, solar energy and other industries, high-purity quartz sand as an important raw material, its importance is increasingly prominent.
The impurity elements in quartz sand will significantly affect the performance of quartz products, in which iron and other transition metals will affect the light transmittance and conductivity of quartz products; potassium, sodium and other alkali metal impurity content is too high will reduce the high temperature resistance of quartz products, which affects its thermal stability and optical properties. To obtain quartz sand of super high quality, it needs to be purified.
Acid washing is an indispensable step in the purification of quartz ore, the use of quartz is insoluble in acid, other impurities can be dissolved by the characteristics of the acid minerals, the realization of the quartz beneficiation and purification, the commonly used acids such as sulfuric acid, hydrochloric acid and hydrofluoric acid.
However, although the removal rate of acid washing quartz sand impurities is higher, but the removal of wastewater treatment is not appropriate, will cause serious impact on the environment, soil and so on. There are a large number of H+, F- and other ions remaining in the pickling waste water, which is prone to cause fluorine pollution, corrosion of underground pipes, groundwater contamination and other serious consequences if it is directly discharged without treatment.
The following is an introduction to several common quartz sand pickling waste treatment process:
(1)Neutralization + precipitation process
Quartz pickling waste through the drainage pipe into the regulating pool, fully regulate the quality of the pickling waste water, water, water, through the pump will be regulated wastewater elevated to the acid and alkali reaction pool, add alkaline substances (caustic soda, sodium bicarbonate, lime) The alkaline substances (caustic soda, sodium bicarbonate, lime, etc.) are added to neutralize and react with the pickling waste liquid, stirring while adding, and after the acid and alkaline are neutralized for a period of time, the upper layer of the clear liquid in the reaction pool overflows into the precipitation pool, and the water quality is tested after settling, and is discharged or recycled after reaching the standard.
(2) Neutralization + precipitation + flocculation + filtration dewatering process
Acid washing wastewater is directly discharged into the adjusting tank, which is equipped with perforated aeration tubes to homogenize and mix the wastewater. Wastewater is lifted by the lifting pump from the regulating tank to the batch treatment tank for the first neutralization reaction to remove most of the pollutants in the wastewater.
The wastewater sludge after the neutralization reaction is settled in the batch tank, and the settled wastewater continues to be coagulated in the batch tank for the second level, which completely removes the pollutants in the wastewater and ensures that it meets the standards for discharge. Wastewater after coagulation reaction, soluble pollutants are completely removed, wastewater in the sand filtration process of suspended solids.
(3)Neutralization+Press dewatering+Multi-stage filtration+Reverse osmosis process
Quartz pickling wastewater firstly enters into the adjusting sedimentation tank, adding lime water, adjusting the PH to 8.5~9.5. After a period of reaction, flocculant is added to coagulate the debris in the water and the sludge, which can play the role of better solid-liquid separation, the separated sludge then enters into the sludge tank, and the suspended matter is treated in the sand filtration process. The separated sludge goes into the sludge tank and is dewatered by plate and frame filter press and then transported out.
The supernatant of the regulating sedimentation tank is lifted by the raw water pump, then passes through the quartz sand filter, activated carbon filter, and then into the security filter, and then pressurized by the high-pressure pump into the reverse osmosis membrane group, and the produced concentrated water returns to the regulating sedimentation tank, and the product water enters the reuse pool, reuse or discharge.
? (4)Haipu special adsorption technology
Jiangsu Haipu Functional Materials Co., Ltd. is located in Suzhou Industrial Park, is a special adsorbents, catalysts as the core technology, supporting the application of process development, technical services, engineering implementation, etc., to solve the relevant environmental protection problems for the customer's national high-tech enterprises.
Jiangsu Hai Pu Functional Materials Co., Ltd. has a leading technical level in adsorbent material processing, supporting the adsorption treatment process is efficient, stable, and for a number of domestic leading enterprises to solve a number of environmental problems.
The basic principle of Hai Pu special adsorption technology is to use the adsorption performance of special adsorbent materials to adsorb iron, calcium, magnesium ions in the waste acid and enrich the adsorbent material, adsorption of acid ions out of the content of the reduction to meet customer requirements. After the adsorption is saturated, the adsorption material is desorbed, so that the adsorption material can be regenerated and continue to adsorb again, and so the cycle continues.
Process FlowThe process flow is shown in Figure 1-1, the wastewater is first filtered to retain the suspended and fine particles, to prevent impurities from entering the adsorption material, affecting the adsorption performance. Filtered wastewater into the adsorption tower with special adsorption materials for adsorption, adsorption saturation, the adsorption material for desorption regeneration processing, adsorption material regeneration can be reused. The adsorbed acid is recycled by the customer, and the high concentration desorption liquid is treated by the customer.
Figure 1-1 Process Flow Diagram
Scope of ApplicationQuartz sand pickling wastewater;
Cases of Adsorption TreatmentOur company conducted several batches of adsorption and desorption experiments on materials sampled from the site of a project, and the specific experimental results and comparison charts before and after the treatment are as follows:
Case 1?Data of inlet and outlet of adsorption water
Figure 2-1 Waste Acid Adsorption Schematic diagram
Advantages1.Solve the problem of waste acid treatment, adsorption of acid can be recycled to ensure the sustainable development of enterprises, with greater economic and environmental benefits;
2.Special adsorption materials with high absorption capacity and high concentration ratio, less investment in equipment, low operating costs;
3.Automation control, easy to operate, easy to maintain, long service life;
4.
4. Simple and reliable process, small footprint.