twenty four. How are pollutants in wastewater discharged from printing and dyeing auxiliaries classified?
Answer Pollutants in wastewater discharged from printing and dyeing auxiliaries are divided into 5 categories according to their degree of hazard.
① Relatively harmless, inorganic pollutants (hazard level 1). The main types of pollutants include alkalis, inorganic acids (hydrochloric acid, sulfuric acid, phosphoric acid), salts (salt, sodium sulfate, silicate), and oxides (hydrogen peroxide).
②Medium to high BOD value, but easy to biodegrade (hazard level 2). The main types of pollutants include starch slurry, vegetable oils, waxes, organic acids (formic acid, acetic acid, oxalic acid), reducing agents (sulfites, sulfides, thiosulfates), and biodegradable surface active substances. agent.
③Additives and polymers that are difficult to biodegrade (hazard level 3). The main types of pollutants include fluorescent whitening agents, most fiber and polymer impurities, polyacrylate slurries, fire retardants, anti-shrink and anti-wrinkle finishing agents, water repellents, softeners, etc.
④Medium BOD value, but difficult to biodegrade (hazard level 4). The main types of pollutants include PVA slurry, lanolin, and difficult-to-biodegrade surfactants.
⑤The BOD value is very small and cannot be degraded by traditional biochemical treatment (hazard level 5). The main pollutants include fungicides (pentachlorophenol), N-hydroxymethyl reactant, formaldehyde, hydrogenated hydrocarbon solvents and carriers, cationic retardants, softeners, organic metal complexes, heavy metal salts (mercury, chromium, copper, tin, magnesium).
Surfactants with medium to high BOD values but easily biodegradable, such as linear anionic surfactants and non-ionic surfactants with short-chain ethylene oxide adducts, have low hazard levels. Some anionic surfactants and nonionic surfactants with medium to low BOD values are difficult to biodegrade and are more harmful. However, cationic dye retardants and softeners with very small BOD and poor biodegradability are more harmful.
AAAASE3RETRUY7I8OFG
Disclaimer:
Disclaimer: Some of the texts, pictures, audios, and videos of some articles published on this site are from the Internet and do not represent the views of this site. The copyrights belong to the original authors. If you find that the information reproduced on this website infringes upon your rights, please contact us and we will change or delete it as soon as possible.
AA
