The main component of the crimson sewage of the paper mill

This red color may be used in the factory, and the main pollutants emitted during the papermaking process are:

Suspended solids: including settling suspended solids and non-settling suspended solids, mainly fibers and fiber fines.

Easily biodegradable organic matter: the raw material components are dissolved in the pulping and bleaching process, which are generally easily biodegradable, including low molecular weight hemicellulose, formic acid, acetic acid, formic acid, sugar, etc.

Toxic substances: mainly include: rosin acid and unsaturated fatty acids contained in black liquor; The condensate contains components that are particularly toxic to fish: hydrogen sulfide, methyl sulfide, and methyl sulfide; Bleaching alkali extracts a variety of chlorinated organic compounds from wastewater, among which the highly toxic dioxin has attracted widespread attention.

Acid and alkali substances: the acid and alkali substances in the pulping wastewater can significantly change the pH of the receiving water, the pH of the alkali pulping wastewater is 9 10, and the pH of the bleaching wastewater varies greatly, which can be lower than 2 and higher than 12; In some acid pulp mills, the pH of wastewater is as low as: Chromaticity:

The residual lignin contained in pulping wastewater is a highly colored substance,。。 Toxic substances have been marked,。。

Acid pulping produces red liquor, the main components of which are sulfates, sulfites and lignin.

The main components of the crimson sewage discharged from the production of paper mills generally include the following Zhongzhou Min:

1.Organic matter: Dark red sewage contains a large amount of organic matter, such as cellulose, lignin, hemicellulose, protein-like substances, etc.

2.Acidic substances: In the papermaking process, the concentration of acidic substances is also relatively high, such as oxides containing chlorine, amino acids, etc.

3.Heavy metals such as arsenic, lead, mercury, etc.: These heavy metals enter the wastewater due to the presence of raw materials or treatment agents in the paper production process.

4.Fibers and fillers: Wood fibers, straw, cotton, and other fillers added to the papermaking process can also be found in crimson trails.

5.Other additives: such as preservatives, talcum powder, red mud, etc.

The crimson sewage of the paper mill contains many harmful substances, which cause serious pollution to the environment, and the discharge concentration of harmful substances exceeding the standard may also pose a serious threat to human beings and the ecological environment. Therefore, paper mills must take effective treatment measures to reduce the discharge concentration of dark red sewage and realize the recycling of resources.

The composition of pulp and paper wastewater is complex, and its composition depends not only on the pulp method, but also on various factors such as the type of product and the type of raw material. The suspended substances in the wastewater of the paper industry mainly come from the bark, grass clippings, sediment in the preparation section, and the ash and slag discharged with the water, and the fibers and fillers lost in the pulp and paper making processes. BOD in wastewater is mainly used in the pulping and cooking process, such as sugars, alcohols, organic acids, etc., which are generated by cellulose decomposition, and the BOD5 of cooking waste liquid accounts for more than 80% in chemical pulp; The COD and coloring substances in the wastewater are mainly the lignin and its derivatives in the pulping and cooking process; The toxic substances in the wastewater mainly include crude sulfate soap in the cooking waste liquid, the organochlorides in the bleaching wastewater (such as dichlorophenol, chloroccinol, etc.), as well as trace amounts of mercury, phenol, etc., but these toxic substances are usually in very small content, among which the toxicity and "three-caused" effect of the organochlorides in the bleaching wastewater have attracted increasing attention in developed countries. In China, due to the large proportion of grass fiber raw materials (about 60%), the scale of enterprises is small, the production process and equipment are backward, raw materials, energy, water consumption, so that the pollution of China's pulp and paper industry is particularly serious, in 1985 estimates, China's paper industry annual discharge of 37 billion cubic meters, second only to the chemical industry and the steel industry, ranking third, accounting for about 1 10 of the total discharge of industrial wastewaterThe discharged BOD5 load is 210kg per ton of product, and the annual BOD5 emission is 1.73 million tons, accounting for 1 4 of the total BOD5 emissions in the country.

Paper mill or pulp mill? In the case of the paper mill, it is either the water that has finished making paper and left for a period of time, because some of the nutrients in it breed algae; It could also be a stain.

Is paper mill sewage sludge used as agricultural fertilizer with filtered pollutants? Does the public pollute the environment?

Hello dear! The milky white base demolition wastewater discharged from the recycled paper mill may contain the following pollutants:1

Organic matter: such as cellulose, lignin, fatty acids, etc. 2.

Suspended solids: such as fibers, sediments, etc. 3.

pH: Wastewater may contain acidic or alkaline substances, such as sulfuric acid, sodium hydroxide, etc. 4.

Heavy metals: such as copper, lead, zinc, etc. 5.

Nutrients such as nitrogen and phosphorus: These substances may cause eutrophication of water bodies and cause damage to water ecosystems. 6.

Chloride ions, fluoride ions, etc.: These substances may cause effects on water ecosystems, such as affecting the growth and reproduction of aquatic organisms.

Depending on the raw materials and processes you produce, the composition of the wastewater pollution generated by different production processes will vary greatly.

Alkaline pulping middle wastewater: fiber, heterocellular, hemifiber, methanol, acetic acid, formic acid, sugar, lignin and derivatives, rosin acid and unsaturated fatty acids.

Mechanically ground wood pulp, semi-chemical pulp sewage: mainly fiber, lignin and derivatives, gelatin, etc.

Waste paper deinking wastewater: the main components are fibers and degradants, colloids, inks, deinking agents and other surfactants.

Contaminants are SS, COD, color, fine fiber fillers and additives, etc.

There are sulfides left in the wastewater during the cooking process, chlorine and alkali residues in the wastewater from bleaching and washing, and rosin gum and talcum powder residues in the wastewater from paper molding. Among them, the first two are more polluted.

Most of them are fine fibers, and some chemicals, flow aids, dispersants, fluorescent brighteners, bleach, hydrogen peroxide ,..All of them are high carcinogens to humans.

1. Bleaching chemical residues, many bleaching processes still use chlorine or hypochlorite bleaching'2, chlorine can be combined with some organic substances to form carcinogens; 3. The sulfide in the cooking black liquor is slow, etc., 4. The discharge of some substances needs to be judged and consumed a lot of oxygen, which will cause the oxygen content in the water body to drop and make the aquatic animals in it.