高藻水臭氧预氧化过程有机物转化及消毒副产物生成势

研究了高藻水预氧化处理过程中,不同臭氧氧化程度及不同pH值条件下,藻类有机物释放与转化规律以及氯化消毒副产物(DBPs)的生成特性.结果表明,臭氧投加量为28.92 mg·L-1时藻去除率达36%.随着臭氧投加量的增加,藻的去除率进一步增加,类腐殖酸先增加后持续减少,溶解性微生物代谢产物、类富里酸和类芳香蛋白物质持续减少;低投加量的臭氧对二氯乙腈(DCAN)、三氯乙腈(TCAN)生成势有明显的控制作用,但会增加三氯硝基甲烷(TCNM)以及1,1,1-三氯丙酮(1,1,1-TCP)前体物,随臭氧投加量增大,DBPs生成势显著增大.酸性条件下臭氧对藻的去除效果最好,UV254以及总有机碳(DOC)均随pH的增大有所上升,但变化较小;臭氧氧化可降解溶解性微生物代谢产物,降解效果受pH影响较小,类腐殖酸有机物随pH值增大而减少;DCAN、TCAN生成势随pH增大有所降低,TCNM生成势在pH=10条件下最高,1,1,1-TCP生成势在pH=7条件下最高.

Peroxidation of High Algae-laden Water by Ozone: Algae Organic Matter Transformation and Disinfection By-products Formation

Formation characteristics and transferring feature of nitrogenous/carbonaceous disinfection by-products have been observed under different ozone dosages and pH conditions, and essential nature conversion of Algae organic matters has been also studied concurrently, based on high algae-laden water. The results showed as follows:reduction of Microcystis aeruginosa could reach 36% at the ozonation concentration of 28.92 mg·L^-1. Humic acid-like compounds first increased and then decreased with continuing addition of ozone dosage, whereas soluble microbial products, fulvic acids and aromatic protein substance all diminished. Low dosage of ozone had certain effect on control of dichloroacetonitrile(DCAN) and trichloroacetonitrile (TCAN) formation potential, yet augmented the yield of trichloronitromethane (TCNM) and 1,1,1-trichloroacetone(1,1,1-TCP) precursors, and N-DBPs formation potential was promoted with the increase of ozone dosage. Algae removal efficiency was relatively the best under the acidic condition, meanwhile, UV₂₅₄ and DOC increased with the rise of pH, though the change was not outstanding. Humic acid-like compounds decreased with the rise of pH; ozonation could degrade the soluble microbial products and the consequence was affected little by the change of pH. DCAN and TCAN formation potential decreased with the rise of pH; TCNM formation potential appeared to be the highest when the pH was 10, whereas the highest 1,1,1-TCP formation potential was found at pH 7.