印染生化物化尾水反渗透回收特性

Recovery characterization of effluent from printing and dyeing wastewater treated with biochemical and physicochemical processes by reverse osmosis

利用反渗透对印染生化物化尾水进行回收,考察了分离浓缩过程中,浓缩液和透过液水质随体积浓缩倍数(CF)变化情况,探讨印染生化物化处理尾水反渗透回收机制。研究结果表明,分离浓缩过程中,通量随CF的增加呈线性下降,CF为5时,降低了32.6%。透过液中COD未检出,浓缩液COD与CF呈近似线性关系。Na+、K+、Ca2+和Mg2+富集倍数随CF线性上升,但在高倍数下增大幅度反而降低;Fe、Mn和Al富集情况与主要无机阳离子相似,但程度略低。Cl-和SO2-4基本富集在浓缩液中,NO-3和NO-2也得到较好的富集,但截留率略低。透过液中无机离子主要为Na+和Cl-。

The pilot-scale experiments were conducted to investigate recovery of effluent from printing and dyeing wastewater treated with biochemical and physicochemical processes by reverse osmosis（ RO）. Characteristics of water quality of the concentrate and the permeate with concentration factor（ CF） were performed during separation and thickening process and RO recovery mechanism were also discussed. The results show that the permeate flux decreased relatively linear with the increase of CF,with a reduction flux value of 32. 6% at CF =5 during the process of separation and thickening. Variation of the concentrate COD with CF showed a linear relationship,and the permeate COD was lower than the detection limit. The enrichment factors of major inorganic cations Na＋,K＋,Ca2 ＋and Mg2 ＋increased linearly with the increase of CF,however,their enriching extent dropped under high value of CF. Variations of enrichment state of Fe,Mn and Al with CF were similar to major inorganics,but the enrichment factors were lower to some extent. Both Cl-and SO2-4were completely rejected in the concentrate,also NO-3and NO-2,just a few lower rejection rate. Na＋and Cl-dominated in inorganic ions of the permeate.