Technology for discharging desulfurized wastewater according to standards

Abstract

The invention provides a technology for discharging desulfurized wastewater according to standards. The technology includes the steps of pretreatment, secondary filtering and discharging. In the stepof pretreatment, after a compound reagent which does not exceed 300 ppm is added, heavy metal, COD substances and suspended solids in the desulfurized wastewater form sediments, and the sediments arefiltered away primarily; in the step of secondary filtering, the pH value of filtrate after primary filtering is adjusted to be 6-9, and sediments are filtered away secondarily; the step of discharging includes discharging of filtrate after secondary filtering.

Description

technical field [0001] The invention relates to the technical field of wastewater treatment, in particular to a desulfurization wastewater discharge process up to standard. Background technique [0002] The existing desulfurization wastewater treatment system is a "triple tank + clarification" process. The triple tank includes a neutralization tank, a reaction tank and a flocculation tank. Lime milk or sodium hydroxide is added to the neutralization tank of the triple tank, and the original Acidic wastewater is alkaline, and most of the heavy metals and fluoride ions form insoluble substances and precipitate out of the wastewater during this process. The effluent from the neutralization tank flows to the reaction tank by itself, and organic sulfur and coagulant are added to the reaction tank to remove the residual heavy metals that cannot be precipitated in the form of hydroxides in the form of sulfide precipitation. The effluent from the reaction tank enters the flocculatio...

AI Technical Summary

Problems solved by technology

[0003] However, the process requires a wide variety of agents (5 or more), and the dosing system is prone to failure (such as lime compaction often occurs). The simultaneous use of multiple agents makes the overall dosing stability poor, and the clarification system is unstable. , the adjustment and management are difficult, the SS, COD and heavy metal content of the effluent during operation are easy to exceed the standard, the discharge compliance rate is low, and it is difficult to directly apply the return water or reuse it after subsequent treatment; secondly, there are many operating equipment, and the operation management is relatively complicated; and then Or, there are many supporting equipment, such as dosing equipment, and the solid content of muddy water from the clarification process is low, most of which cannot directly enter the filter press unit, and need to be equipped with sludge adjustment, concentration and balance systems; moreover, most of the desulfurization wastewater is The renovation project is limited in land use, and its numerous main process units and complex supporting processes lead to a large site occupation and high requirements for the overall implementation of the project

Images