What are Paper Mills?

Paper mills are mills that make paper in the form of mechanical lines. There are two types of papermaking: mechanical and manual. The mechanism is carried out continuously on a paper machine. The pulp suitable for paper quality is diluted with water to a certain concentration, and is initially dehydrated in the net of the paper machine to form a wet paper sheet, which is then dewatered by pressing and then dried into paper. Manually, a frame with bamboo curtain, polyester mesh or copper mesh is used to copy the fibers suspended in water into wet paper sheets, which are dewatered by pressing, and then dried or dried to form paper.

Paper mill

From January to December 2006, China's paper industry achieved a cumulative total industrial output value of 311,931,253 thousand yuan, an increase of 21.28% over the same period of the previous year; a cumulative product sales income of 303,777,560 thousand yuan, an increase of 21.69% over the same period of the previous year; a cumulative total profit of 15,102,407 thousand Yuan, an increase of 27.76% over the same period last year.

From January to December 2007, China's paper industry achieved a cumulative total industrial output value of 383,295,712 thousand yuan, an increase of 23.56% over the same period of the previous year. From January to October 2008, China's paper industry achieved a cumulative total industrial output value of 382,007,566 thousand yuan, a year-on-year increase. Up 26.16%.

Compared with the national enterprises as a whole, the size of Chinese papermaking enterprises is significantly smaller and their operating income is not high. According to 2007

North America American International Paper (International Paper) Mead / Westvaco United States Kimberly Clark United States

The invention and development of paper also went through a tortuous process. After the invention of papermaking in AD 105,

For paper mill wastewater treatment

Equipment for paper mills

To purify the waste water discharged from the paper mill, it is first necessary to understand the water quality characteristics of the paper mill. Papermaking wastewater has high COD and suspended matter (SS) content and serious chromaticity. The concentration of SS and COD in papermaking wastewater is high. COD is composed of two parts: insoluble COD and soluble COD. Generally, insoluble COD accounts for most of the total COD composition. When SS is removed from wastewater, most of them Insoluble COD is removed at the same time. Therefore, the main problem to be solved in waste paper and papermaking wastewater treatment is to remove SS and COD.

By air flotation or precipitation method, by adding cationic polyacrylamide, most of the SS can be removed, and most of the non-soluble COD and partially soluble COD and BOD can be removed at the same time. The typical processing process is as follows:

Waste water screens catchment tanks air flotation or sedimentation discharge

Air flotation and precipitation are both physical and chemical treatment methods. The treatment effect is related to the selected equipment, process parameters, coagulant, etc. The COD removal rate is generally higher than the COD removal rate of water in the middle of pulping, which can usually reach 70% to 85% . For small and medium-sized waste paper making enterprises with a discharge volume of more than 150m3 per ton of paper and low concentration, through air flotation or sedimentation treatment, the effluent water quality indicators can meet or approach national discharge standards.