Polyformaldehyde wastewater treatment device and wastewater treatment technique using device

Abstract

The invention relates to a polyformaldehyde wastewater treatment device and a wastewater treatment technique using the device. The polyformaldehyde treatment device comprises a pretreatment system and a biochemical treatment system which are sequentially communicated from upstream to downstream, wherein the pretreatment system comprises an iron carbon reactor, a Fenton-like reactor and a precipitation tank which are sequentially communicated from upstream to downstream; and the biochemical treatment system comprises a one-stage hydrolysis acidification tank, a formaldehyde pretreatment tank, a UASB (upflow anaerobic sludge blanket) reactor, an intermediate precipitation tank and an aerobic treatment unit which are sequentially communicated from upstream to downstream. Due to the adoption of the composite physicochemical oxidation process-biological process combination technique and the adoption of the iron carbon electrode reaction-Fenton-like reaction combination pretreatment mode in the pretreatment stage, the subsequent biochemical treatment provides favorable reaction basis. In the biochemical treatment stage, a UASB reaction-two-stage aerobic reaction combination treatment mode is adopted, so that the micromolecules of the organic matters are thoroughly converted into the molecular state for discharge, thereby greatly lowering the COD (chemical oxygen demand) value and basically implementing zero pollution discharge on polyformaldehyde wastewater.

Description

Technical field [0001] The invention relates to wastewater treatment technology, and more specifically to a polyformaldehyde wastewater treatment device and a wastewater treatment process using the device. Background technique [0002] At present, polyoxymethylene (POM) has been widely used in automobiles, consumer goods, machinery industry and other fields, and has rapidly developed into one of the five major engineering plastics. Moreover, with the development of some new industries, my country's demand for polyformaldehyde is also rising sharply. At the same time, my country has overcapacity of methanol. The development of polyformaldehyde projects is one of the ways to solve this situation. Therefore, in recent years, many polyoxymethylene enterprises have been constructed and put into production in China, but the wastewater discharged by them cannot meet the increasingly stringent discharge standards, which not only causes serious harm to the ecological environment, but also...

AI Technical Summary

Problems solved by technology

Pollutants produced in the production of polyoxymethylene process include dioxane, paraformaldehyde, dioxane, sodium formate, methanol, etc. At the same time, due to the characteristics of the polymerization reaction, many by-products will be generated, and the waste water content is very large uncertainty

The wastewater produced by the polyoxymethylene plant contains dimer, paraformaldehyde, dioxane, etc., which are all macromolecular refractory pollutants. In the prior art, it is difficult to degrade completely only by the common metabolism of aerobic biochemical treatment. The corresponding It is difficult for COD to meet the requirements of emission standards, so pretreatment measures such as physical oxidation or hydrolytic acidification are required to decompose it into low-molecular organic matter, which can be biochemically degraded

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