【摘要】：腌制廢水是以食鹽為主要腌漬成分制作產(chǎn)品過程中產(chǎn)生的廢水。腌制廢水具有高有機物、磷、氮的特點,尤其它具有的高鹽特性會明顯抑制常規(guī)生物處理工藝,使得處理腌制廢水過程難度增加。本課題進行腌制廢水預(yù)處理(氣浮、混凝沉淀)、生化處理(MBR)和深度處理(活性炭吸附、紫外線殺菌)及影響因素研究,并從生化工藝馴化成熟的耐鹽活性污泥中分離純化出具有高效去除污染物的耐鹽菌,開展菌株特性研究,以實現(xiàn)高鹽、高濃度有機廢水的高效處理,同時為工藝的工程實際應(yīng)用提供技術(shù)支持,對水處理技術(shù)產(chǎn)業(yè)化應(yīng)用與推廣具有重要意義。采用氣浮方法對腌制廢水預(yù)處理,通過試驗確定當曝氣量為4L/h時,出水COD、SS值分別降到14680mg/L和35mg/L,對COD、SS去除率分別為26.6%和65%。采用混凝沉淀方法對腌制廢水預(yù)處理,經(jīng)過試驗確定最佳混凝劑為聚合氯化鋁、最適投藥量為100mg/L、最佳廢水pH值為8.5,對廢水的處理效果最好,此時廢水的COD、SS值為12780mg/L、69.1mg/L,去除率分別是36.1%和30.9%。采用膜生物反應(yīng)器(MBR)工藝對腌制廢水進行處理,經(jīng)過試驗確定MBR法最佳溶解氧(DO)、最佳水力停留時間(HRT),當DO為1～1.5mg/L、HRT為12h時,對廢水的處理效果最好,此時對COD的去除率為92%左右。采用活性炭吸附對經(jīng)生化處理后腌制廢水進行處理,經(jīng)過試驗確定活性炭吸附最佳濾速,當濾速為4.2m/h時,出水COD值為43mg/L,此時COD的去除率為34%。采用紫外線殺菌對經(jīng)生化處理后腌制廢水進行處理,經(jīng)過試驗確定紫外線照射最佳時長、廢水極限濁度,當照射時間為2min、廢水濁度為8NTU時,對廢水的處理效果可達最佳,此時出水的細菌總數(shù)和大腸菌群數(shù)均不足100個/L。以生化工藝馴化成熟的耐鹽活性污泥為菌種來源,通過篩選分離出12株高效耐鹽菌,經(jīng)過形態(tài)觀察、生理生化試驗、PCR擴增、16SrRNA序列測序,鑒定12株耐鹽菌均為鹽單胞菌屬Halomonas sp.)。考察鹽度為9%、15%、18%、21%時菌株的生長特性,發(fā)現(xiàn)12株菌在鹽度5%-15%時生長情況良好,接種后能迅速進入對數(shù)生長期,當鹽度超過15%時,12株菌均未呈現(xiàn)良好的生長態(tài)勢,得出菌株生長的耐鹽性可達15%。在不同鹽度(6%、9%、15%)下,所分三組菌株對COD去除率達到75%以上,對于氨氮去除率達到62%以上。對三組菌株影響因素進行考察,發(fā)現(xiàn)培養(yǎng)條件一定下,在pH值為中性7-8,溫度為30～35℃時,三組菌株對污染物的去除效果最好,此時三組菌株對COD的去除率均在80%-90%之間。
[Abstract]:Pickling wastewater is produced in the process of making products with salt as the main pickling component. Pickled wastewater has the characteristics of high organic matter, phosphorus and nitrogen, especially its high salt property will obviously inhibit the conventional biological treatment process, which makes it more difficult to treat pickled wastewater. In this paper, pretreatment of pickled wastewater (air floatation, coagulation and sedimentation), biochemical treatment (MBR) and advanced treatment (activated carbon adsorption, ultraviolet sterilization) and its influencing factors were studied. The salt-tolerant bacteria with high removal efficiency were isolated and purified from the salt tolerant activated sludge domesticated by biochemical process, and the characteristics of the bacteria were studied in order to achieve the efficient treatment of high salt and high concentration organic wastewater. At the same time, it provides technical support for the practical application of technology, which is of great significance to the industrialization and popularization of water treatment technology. The air flotation method was used to pretreat the pickled wastewater. When the aeration rate was 4L/h, the COD,SS value of the effluent was reduced to 14680mg/L and 35 mg / L, respectively, and the removal rate of COD,SS was 26.6% and 65% respectively. The method of coagulation and precipitation was used to pretreat pickled wastewater. The optimum coagulant was polyaluminium chloride, the optimum dosage was 100mg / L, the optimal pH value of wastewater was 8.5, and the treatment effect of the wastewater was the best. The COD,SS of wastewater is 12780 mg / L ~ (-1) mg / L, and the removal rate is 36.1% and 30.9% respectively. The (MBR) process of membrane bioreactor was used to treat the pickled wastewater. The best MBR method was determined to be the best for the treatment of the wastewater when the best HRT of (DO), was 12 h when the DO was 1 ~ 1. 5 mg 路L ~ (-1) 路L ~ (-1) h. The removal rate of COD is about 92%. Activated carbon adsorption was used to treat pickled wastewater after biochemical treatment. The optimum filtration rate of activated carbon adsorption was determined by experiments. When the filtration rate was 4.2m/h, the COD value of effluent was 43 mg / L, and the removal rate of COD was 34%. UV sterilization was used to treat pickled wastewater after biochemical treatment. The optimum time of ultraviolet irradiation and the limit turbidity of wastewater were determined by experiments. When the irradiation time was 2 min and the turbidity of wastewater was 8NTU, the treatment effect of wastewater was the best. The total number of bacteria and coliforms in the effluent was less than 100 / L. Twelve strains of high-efficiency salt-tolerant bacteria were isolated by screening 12 strains of salt-tolerant bacteria from activated sludge domesticated by biochemical process. After morphological observation, the sequence of 16s rRNA was amplified by physiological and biochemical experiments, and all 12 strains of salt-tolerant bacteria were identified as Halomonas sp.). Of halomonas. By investigating the growth characteristics of the strain at salinity of 9 and 21, we found that the 12 strains grew well at the salinity of 5- 15%, and could enter the logarithmic growth period quickly after inoculation, and when the salinity exceeded 15, none of the 12 strains showed a good growth trend. The results showed that the salt tolerance of the strain could reach 15%. Under different salinity (15%), the COD removal rate and ammonia nitrogen removal rate of the three groups of strains were more than 75% and 62%, respectively. The influence factors of three groups of strains were investigated. It was found that when the pH value was neutral 7-8 and the temperature was 30 ~ 35 鈩，

本文編號：2220566