Method and system for treating industrial wastewater of photovoltaic solar cell plates

Abstract

The invention discloses a process for treating industrial wastewater of photovoltaic solar cell plates. The process comprises the following steps of: collecting wastewater, namely collecting acid wastewater and alkaline wastewater respectively; regulating pH, namely adding strong acid or strong base into the acid wastewater, alkaline wastewater or acid-alkaline mixed wastewater mixed by the acid wastewater and the alkaline wastewater, and regulating the pH value to be between 8.0 and 8.5 to form conditioning fluid; defluorinating the conditioning fluid and/or removing chemical oxygen demand (COD) from the conditioning fluid, wherein the defluorinating step means throwing calcium salt into the conditioning fluid so as to remove fluorion from the wastewater, and the COD removing step means performing incomplete anaerobic reaction on the conditioning fluid; performing aerobic biological treatment; and sequentially completing the steps to discharge the wastewater meeting the discharge standard. The invention provides a treatment process aiming at the water quality characteristics of the industrial wastewater of the photovoltaic solar cell plates and main design operational parameters.By a treatment system, the fluorion can be effectively removed, the fluorion concentration of effluent can be reduced to be below 10mg/L, and the wastewater CODCr is below 300mg/L and meets the discharge standard. Meanwhile, the invention also provides a system for treating the industrial wastewater of the photovoltaic solar cell plates.

Description

technical field [0001] The invention relates to a waste water treatment process, in particular to a process for treating waste water produced by photovoltaic solar cells and a waste water treatment system used in the method. Background technique [0002] Under the pressure of global energy crisis and climate warming, the development of renewable new energy industry has attracted more and more attention. Using the inexhaustible clean energy endowed by nature, such as the development of solar energy, can not only solve the problem of energy shortage in the future, but also solve the environmental problems caused by the long-term dependence of human beings on fossil fuels. [0003] Driven by the government's policies, regulations and action plans, the production of solar cells is growing rapidly as a sunrise industry. In the past 15 years, the global photovoltaic industry has grown at an average annual rate of 25%. From 2000 to 2009, the compound annual growth rate of global p...

AI Technical Summary

Problems solved by technology

[0005] 1) Wastewater is extremely acidic and alkaline;

[0006] 2) The fluoride ion concentration is high, and the fluoride ion concentration is often thousands or even tens of thousands of ppm;

[0007] 3) The total dissolved solids content is high. Due to the use of a large amount of strong acid and strong alkali in the production of solar cells, a large amount of inorganic ions are brought into the discharged wastewater, resulting in a high total dissolved salt content;

[0010] 1) pH adjustment consumes a large amount of acid and alkali;

[0011] 2) The content of fluoride ions is high, and it is necessary to choose reasonable agents and treatment processes to meet the emission standards below 10mg / L;

[0012] 3) The total dissolved salt is high, and due to the addition of a large amount of chemicals in the process of removing fluoride ions, the total salt content of the wastewater is high and the hardness is high, which inhibits the traditional biological treatment system and the COD removal effect is not ideal

However, the environmental pollution caused by its production wastewater has not been paid enough attention.

At present, many enterprises only use simple flocculation and sedimentation, adding calcium carbide slag or lime to adjust pH and remove some fluorine for this kind of wastewater. The resulting COD is not removed; at the same time, some enterprises adopt traditional biological treatment systems, but because the solar cell production wastewater is extremely acidic and alkaline, a large amount of chemicals need to be added before biological treatment, resulting in a salt content of more than 2% in the wastewater , the hardness of the wastewater is high, so the simple use of the traditional biological treatment system is often inhibited by high salt and high hardness, the biological treatment effect is extremely poor, the COD removal is not ideal, the wastewater discharge is not up to standard, and direct discharge will cause serious environmental pollution problems. Discharging into the municipal pipe network will bring a large impact load to the downstream sewage plant, and even affect its normal operation

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