Study On Sodium Hydrosulfite Wastewater Treatment For COD Removal By Sequencing Batch Recator Process

Sodium hydrosulfite wastewater is more difficult to treat in industrial wastewatertreatment. The untreated hydrosulfite wastewater will inflict a serious destruction onwater environment. This subject based on the principle of treating sodium hydrosulfitewastewater in Zhuzhou by SBR process. The article made a thoroughly study andanalysis on starting period, operational aspect and influencing factors of the process,and determined most adequate operational parameter of the process. In addition,itmade a detailed analysis on the question which appeared in the operational process,and sum up the solutions. Research conclusions have a important guiding significancefor the actual operation, and also provide the reference for the better treatment ofsodium hydrosulfite wastewater.First of all, research on the start of SBR system for degrading COD of sodiumhydrosulfite wastewater. The results show that biological toxicity of wastewater hasdecreased after the sodium hydrosulfite wastewater is diluted with treated water, butthere have been still long period of sludge acclimation. During startup, by observingthe sludge flocs, the ratio of sludge settling, as well as the changes of supernatantabsorbance, determine the biological activity of the sludge in the reactor, and thenindicate the effect of the degradation of organic pollutants.Then focuses on researching the running characteristics of SBR process fordegrading COD of sodium hydrosulfite wastewater. The results show that theactivated sludge can adapt the hydrosulfite wastewater after acclimation. SBR processhas a very good removal efficiency of organic matter. The raw water (content of CODand SS respectively are900mg/L and400mg/L) is processed after dilute, the contentof COD and SS respectively reach96mg/L and15mg/L in effluent water, and theremoval rate respectively are89.3%and62.5%. Through experimental analysis,determine the optimum operating parameters of the SBR process: temperature is25~35°C, aeration tank DO is2.5~3.5mg/L, anoxic pool DO is0~0.5mg/L, sludge ageis20d, MLSS is4g/L, sludge load is0.23kgCOD/(kg sludge. d), aeration reactiontime is10h, the static precipitation time is2h, inlet water and outlet waterinstantaneously,12h a cycle to run.The third stage investigated the effects of dominant bacteria in degradation ofhydrosulfite wastewater. The results show that it can isolate the dominant bacteria in the selective culture medium with hydrosulfite wastewater as carbon source, which comes from activated sludge in the stable SBR process. The bacteria is belonging to Gram-positive bacteria after identification, rod-shaped structure, with flagella of bacteria, spores and no capsular. Through experimental analysis, determine the optimum operating parameters of the SBR process, the results of the culture conditions are as follows:with hydrosulfite wastewater as carbon source in the selective culture medium, the concentration of COD is4000mg/L,2.5g of peptone,2.5g of NaCl,500mL of H2O are the ingredients of its culture medium, the best table temperature30℃, the table speed110rpm and20h for its incubation time, medium pH should be7.3to7.6, the inoculation is1%(v/v). Under the best culture conditions, the removal rate of COD is50.3%, content of COD decline from4000mg/L to1988mg/LFinally, through reasonable assumptions, discussed the dynamics model of pollutants removal by SBR process. The dynamics model of COD removal is...