Case name: WACKER waste water Station production wastewater zero discharge treatment project

Project background

Dongguan Wacker precision Metal Technology Co., Ltd. is located in Dongguan City Fenggang town Bihu Industrial zone, belongs to Lianfeng Business Group, the group based on the world famous watch accessories supply at the same time, strong and rapid into the electronic communications industry, has become the main accessories supplier of Apple mobile phone, set up Wacker factory mainly to expand production capacity, the need for the establishment of research and development center.

The main process of generating wastewater in WACKER plant is waxing, cleaning and grinding. If the wastewater is not treated and discharged directly, it will cause serious pollution to the receiving water body. The COD, particulate matter and pH in the water will cause blockage and corrosion of pipelines, rivers and reservoirs, etc. Especially after the natural water body is polluted, the original buffer capacity will be destroyed and the water quality will deteriorate. Inhibit or prevent microbial activity and reduce the self-purification ability of water; At the same time, a large amount of phosphate will cause eutrophication of receiving water. Therefore, according to the requirements of environmental protection, coupled with the concept of circular economy of the enterprise, the wastewater needs to be treated and completely reused.

Treatment technology

The overall design idea of this scheme is zero emission as the core, the so-called zero emission, refers to the unlimited reduction of pollutants
And energy emissions to zero activities. Zero emissions, as far as its content is concerned, one is to control the energy and resource emissions that are forced to occur in the production process, and reduce them to zero as far as possible; Another meaning is to make full use of the energy and resources that are forced to be emitted, and finally eliminate the existence of non-renewable resources and energy. In this scheme, the sewage is reused after evaporation, and the recycling of water resources is realized to the maximum extent.

According to the different functions of each process, the whole zero emission treatment process is divided into four stages, including physical and chemical treatment process, organic sewage biochemical treatment process, deep membrane system concentration process and MVR crystallization evaporation process.

The original wastewater treatment capacity of this project is about 150m³/d, and the process is "coagulation precipitation + biochemical treatment (anaerobic + aerobic) + secondary sedimentation tank". At present, due to the expansion of production line, the amount of production wastewater increases, and the original system can not meet the treatment capacity of wastewater. Due to the limited space of the original wastewater station, the main expansion idea of this scheme is to improve the system process and simplify the equipment area while expanding the treatment capacity of the wastewater station (see the renovation layout diagram for details).

The original waste water station has built civil pond and other treatment facilities for physicochemical + biochemical treatment. Now part of the partition wall of the facility is removed, so that the original pool is connected to each other, and the treatment load of the pool is increased, which is used as the biochemical section treatment system of the system. After the transformation, the process of this section is anaerobic + aerobic +MBR+ clear pool part.

The pre-treatment air float + precipitation system uses integrated equipment, which has the advantages of high processing efficiency and faster manufacturing period while simplifying the footprint.

Multi-media + ultrafiltration, reclaimed water RO, pure water RO and other systems in the rear section of the MBR, some of the original reclaimed water equipment of the wastewater station, and the additional processing capacity of the part, the old reclaimed water equipment and pure water equipment of other plants are relocated to the wastewater station, and the overall planning and layout are reformed to meet the treatment requirements of the existing system.

The SWRO system uses the original equipment to benefit from the old.

STRO system +MVR system is added. The STRO system is used to reconcentrate and reduce the concentrated liquid part of the SWRO system, then enter the MVR evaporation treatment, and the MVR clear liquid is returned to the front section for use, and the final concentrated liquid is disposed of outside.

Treatment effect

After the zero discharge process of the system, the water quality is stable and up to standard, and meets the requirements of factory reuse. The remaining COD, SS and other concentrated waste liquid after evaporation will be treated by qualified units for hazardous waste treatment, so the project will not discharge production wastewater.

Technical characteristics and advantages

Using advanced special membrane separation technology: electroplating wastewater zero discharge system uses membrane separation technology, which has the advantages of low energy consumption, no phase change, no pollution, high separation efficiency and high concentration ratio.

Electromechanical integration design, high degree of automation: electroplating wastewater zero discharge system implementation of electromechanical integration design, high degree of automation, simple operation and maintenance, easy standardized management.

Small footprint, less auxiliary facilities, economic and reasonable equipment configuration, less investment, low operating costs. Wastewater reuse, reduce the amount of rinsing water: electroplating wastewater zero discharge system can achieve wastewater reuse, reduce the amount of rinsing water, further treatment to achieve the "zero discharge" of wastewater, reduce the scale of biochemical, physical and chemical treatment, is conducive to the expansion needs of enterprises.

Conclusion and prospect

The treatment effect of zero discharge of industrial wastewater is mainly reflected in the aspects of water resource conservation and reuse, pollutant reduction and discharge control, stable and reliable treatment effect, economic and social benefits. Through the use of advanced zero-discharge wastewater technology, the effective treatment of industrial wastewater and the recycling of resources can be realized, bringing double benefits to enterprises and society.