Why need to deal with the paper-making waste water and how to take measures to solve this problem?

There is a lot of water in paper making process. It takes about 300-500 M3 to produce one ton of paper. In the paper-making waste water, there are not only a lot of paper making raw materials (about 20% of the raw materials are lost with the waste water), but also a lot of chemicals and other impurities. Therefore, if the paper-making waste water is discharged arbitrarily without treatment, it will cause great harm to the water body. Characteristics of paper making waste water:

1. Waste liquor produced by cooking wood pulp (or straw pulp), also known as black liquor.

2. The effluent discharged from beaters and seminators is called beating effluent.

3. Paper machine sewage, which can be used directly, is called white water.

The main pollution is as follows:

1. Suspended solids include settling suspended solids and non-settling suspended solids, mainly fibers and fine fibers (i.e., broken fibre fragments and miscellaneous cells).

2. Biodegradable organic compounds include low molecular weight nitrocellulose, methanol, acetic acid, formic acid, carbohydrates, etc.

3. The refractory biodegradable organic matter mainly comes from insignia and macro-molecular carbohydrate contained in fibre raw materials.

4. Rosin acid and unsaturated fatty acid in toxic black liquor.

5. The pH value of acid-alkali canto-alkali pulping waste-water is 9-10, and that of acid-alkali pulping waste-water is 1.2-2.0.

6. Residual lignin in chroma pulping waste-water is highly colored.

Membrane bio-reactor (MBFB) is a solid-liquid separation technology based on biological fluidity bed, using powder activated carbon (PAC) as carrier and combining with membrane bio-reactor (MBR), which integrates the physical adsorption of activated carbon, microbial degradation and membrane separation. The powdered activated carbon also provides a special surface for microbial reproduction, and the porous surface of the powdered activated carbon adsorbs a large number of microbial flora. 

Particularly microbial flora with target pollutants as metabolic substrates; at the same time, powdered activated carbon has a strong adsorption capacity for dissolved oxygen in water. Under the condition of high dissolved oxygen, microorganisms oxidize and decompose small molecules of organic matter enriched on the surface of activated carbon, and then use ceramic membrane separation system to separate suspended particles such as water and powdered activated carbon adsorbed organic matter. Flow filtration can further purify waste-water to meet the reuse standard of reclaimed water.