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Standard discharge, reclaimed water reuse and zero effluent discharge

1. As for paper mill wastewater treatment, pulping wastewater is the most difficult wastewater to be treated in the papermaking industry. The organic pollutants and inorganic salts are high in content, complex in composition, high in hardness, high in costs. The technical staff of JIUWU work with experts from the Institute of Membrane Science and Technology of Nanjing Tech University and develop successfully membrane technology as the core of zero effluent discharge process or zld (zero liquid discharge).

2. Using the process of pretreatment, membrane integration, evaporation crystallization and other related processes turns waste into valuable and achieves the sewage recycle. The project forms a major technological breakthrough in the field of wastewater treatment of pulp and paper.

Application background

Industrial water prices continue to rise

Industrial water intake limit

Increased emission water quality standards (COD, TOC, etc)

Enforcement requirements for environmental protection and water reuse rate, etc.

Large demand for fresh water

Large amount of wastewater discharge

The composition of wastewater is complex, and the content of organic pollutants and inorganic salts is high.

Core advantage of process package

Independent research and development, Global First

Turn waste into treasure and realize 100% full reuse of wastewater

Multiple 10,000-ton demonstration projects

Reuse water, salt, and dry mud

The water quality of the produced water is good and meets the requirements for productive reuse.

zld (zero liquid discharge)

Case

Jiangsu Jiuwu Hitech Co., Ltd has done the largest zero liquid discharge project in paper pulp industry. The project is located in Japanese Oji Paper Co., Ltd. (OJI PAPER) in China, the scale of 40000m3/day of papermaking, pulp wastewater. Main processes include ozone-coupled biofilter (removing COD), the integrated membrane system of uf technology and reverse osmosis, electrodialysis (EDR) concentration system, MVR evaporation crystallization system. Through above-mentioned advanced processing system, the realization of wastewater recycling and zero liquid discharge. The clean water is supplied to the power plant desalination system and the production water system, waste salt is supplied to the Transportation Bureau to do snowmelt agent and chemical raw materials. The project which is the world's largest zero liquid discharge project in paper pulp industry has been stably operating for more than 3 years.

JIANGSU JIUWU HI-TECH CO. LTD.,founded in 1997, focus on producing ceramic membrane purification for many years. And JIUWU HI-TECH has become a leading company in the membrane separation industry. We sincerely invite and welcome people from all around the world to invest and create more values together.

In recent years, the wafer industry has developed rapidly, but at the same time, it also produces a large amount of wastewater. The production wastewater mainly comes from the cleaning process of the polysilicon ingot slicing process. The acid-containing wastewater is produced in the cleaning process after the surface treatment of the polycrystalline silicon ingot with the mixed acid. Since the surface treatment is a mixed acid of nitric acid + hydrofluoric acid, the main pollution in the washing wastewater is pH, fluoride, and nitrate. The organic wastewater is produced in the cleaning process of the sliced polycrystalline silicon wafer. Since the cutting fluid (the main component is polyethylene glycol) and the cut micro powder (the main component is silicon carbide) are used for slicing, the main pollutant in the cleaning wastewater is CODCr and SS.

Polysilicon cutting fluid is made up of polyethylene glycol as the main body and added with various additives. It has a suitable viscosity index, good fluidity, and thermal conductivity, and has good dispersion stability and suspension effect on silicon carbide micropowder. A large amount of waste liquid is generated after cutting, and the waste liquid contains a considerable amount of polycrystalline silicon powder, which has a certain recovery value. The polysilicon powder is recovered by the ceramic membrane separation technology, becoming the so-called cutting fluid recovery. And the site is clean and sanitary, which is in line with the national energy-saving and emission-reduction industry orientation.

Ceramic membrane equipment technology is advanced and mature, with low operating costs and fast return on investment.

Ceramic membrane filtration process can directly deal with the waste liquid containing silicon produced in the solar energy production process, collect silicon, reuse pure water and coolant.

The process can separate silicon powder and pure water, recover over 98% of the silicon powder, reuse more than 90% pure water,reuse about 50% of coolant and shaping agent , which can greatly reduce the load of the sewage station.

The process has the advantages of short process, simple operation, short payback period, and has become the preferred standard process for the benchmarking enterprises in the silicon chip industry.