Project Overview and Pain Points
The customer is a semiconductor epitaxial wafer manufacturer, and its main products include semiconductor laser epitaxial wafers and optical detection epitaxial wafers for sensing, semiconductor laser epitaxial wafers for communication and optical detection epitaxial wafers.
There is a stream of phosphorus and arsenic waste water in the production of the enterpriseDue to its high arsenic content, it is now mainly treated as hazardous waste. The amount of wastewater generated is about 1000t a, and the cost of treatment as hazardous waste is high, so it is necessary to reduce the treatment of wastewater to reduce the cost of wastewater treatment.
The amount of phosphorus and arsenic wastewater is about 5t d, and it is treated by other means, which has problems such as long process chain, high equipment maintenance costs, and high requirements for operating personnelIn addition, the wastewater contains arsenic, a highly toxic substance, and the raw water content is as high as 1000-6000mg l, and the effluent is required to be less than 01mg l, the requirements for the treatment process and equipment are very high, and other processes can not meet.
The solution provided by Wasenda Environmental Protection
According to the wastewater water quality index, combined with the on-site public conditions, Weishengda Environmental Protection adopts the treatment process of pretreatment + low-temperature evaporation + crystallization to produce crystalline salt as hazardous waste treatment, and the evaporated condensate is discharged into the sewage station. This process can reduce the amount of hazardous waste by 90%, which greatly reduces the cost of wastewater treatment.
Process flow: Wastewater is collected and transferred to the pretreatment combination pool for pH adjustment, and the pH adjustment is completed and enters the Weishengda LT-5T coiled cryogenic evaporator to concentrate and reduce, the concentration ratio is set to 80%, and the evaporated effluent is discharged after passing the test, and the concentrate is about 1t per day, and continues to enter the Weishengda LTVR-50 equipment for crystallization treatment.
Process. The on-site installation and operation effect of Weishengda cryogenic evaporator
The overall operation of the equipment is stable, and the arsenic content is less than 01mg L, which can be directly discharged up to the standard, saving about 1.7 million yuan in disposal costs annually.
Test results.