Wastewater treatment and clean production in a coated paper mill

The plant products coated white paper with implementing clean production, which toke UASB-aerobic biological treatment system to treat the wastewater and pollutant. Although the new emission standard is deeply rigid, the emission wastewater could satisfy National standard 18918 Grade 1A which is more strictly than National standard 3544-2008. The whole treatment system reduced pollutants to 4.5% and the emission water could be reused. The activated sludge system is maintaining DO at a low level between 0.96 and 1.15mg·L^-1,and HRT 11hrs,which helped to reduce power, and it explains that activated sludge system has great ability to save energy. When the plant toke measures to water-saving, the product consumed fresh water only 7-9 m³·t^-1 much below the half of National standard 3544-2008 requirement.