本文選題：聚合氯化鋁鐵　切入點(diǎn)：含藻絮體堆置　出處：《山東大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：人類活動(dòng)使自然水體富營養(yǎng)化日益嚴(yán)重,藍(lán)藻水華暴發(fā)頻繁且范圍擴(kuò)大,飲用水源也受到藍(lán)藻水華的威脅,飲用水安全問題越來越受到關(guān)注。水華期間大量的藻細(xì)胞和其產(chǎn)生的有毒代謝產(chǎn)物,使水體水質(zhì)急劇惡化,威脅著人類的生命健康。銅綠微囊藻是暴發(fā)藍(lán)藻水華水體中常見的重要優(yōu)勢藻種,也是毒性最大的微囊藻毒素的主要產(chǎn)毒藻種。大部分的微囊藻毒素集中在細(xì)胞內(nèi)部,因此,飲用水廠在處理高藻水時(shí),把藍(lán)藻細(xì)胞完整無破損去除具有重要意義�；炷恋硎秋嬘盟畯S常規(guī)生產(chǎn)的核心工藝,能有效的去除水中的藍(lán)藻細(xì)胞,但需要關(guān)注混凝過程對(duì)藍(lán)藻細(xì)胞完整性的影響。本文采用聚合氯化鋁鐵(PAFC)混凝劑去除模擬原水中的高密度藍(lán)藻細(xì)胞,考察了混凝的最優(yōu)條件,及在最優(yōu)混凝條件下混凝過程和含藻絮體堆置過程對(duì)藍(lán)藻細(xì)胞完整性的影響。通過掃描電鏡和熒光顯微鏡照片,胞外藻毒素變化和三維熒光矩陣光譜,共同評(píng)估藍(lán)藻細(xì)胞破損情況。本文還考察了含藻絮體中微囊藻毒素的厭氧降解條件,避免含藻絮體釋放微囊藻毒素造成二次污染。主要的研究結(jié)果：(1)處理模擬水華狀態(tài)含藻細(xì)胞濃度約為2×106 cells/mL的高藻水,混凝條件優(yōu)化結(jié)果是：PAFC劑量15 mg/L；快攪速度250 r/min,時(shí)間1 min慢攪速度40 r/min,時(shí)間20 min；靜置沉淀時(shí)間20 min,藍(lán)藻細(xì)胞去除率達(dá)99%。(2)混凝劑投加量、快攪速度、慢攪速度和慢攪時(shí)間對(duì)藍(lán)藻細(xì)胞去除率有較大影響,快攪時(shí)間在本實(shí)驗(yàn)設(shè)置的范圍內(nèi)對(duì)藍(lán)藻細(xì)胞去除率影響不明顯。(3)混凝沉淀后,藍(lán)藻細(xì)胞被完整的從模擬水樣中去除,轉(zhuǎn)移到了絮體之中。機(jī)械攪拌和最優(yōu)劑量PAFC的投加不會(huì)造成藍(lán)藻細(xì)胞明顯的破損。(4)含藻絮體在堆置的12 d內(nèi),胞外微囊藻毒素濃度較低,并且從掃描電鏡照片可以直觀看出藍(lán)藻細(xì)胞沒有發(fā)生明顯破損。但是藍(lán)藻細(xì)胞正常生長狀態(tài)被抑制,減少了向胞外釋放有機(jī)物質(zhì)。(5)含藻絮體通過厭氧處理,在初始pH=8,溫度為35℃時(shí),微囊藻毒素在第6d的降解率達(dá)到99%,濃度為1.16μg/L。含藻絮體中微囊藻毒素得到有效降解。
[Abstract]:Human activities make natural water eutrophication more and more serious, cyanobacteria Shui Hua outbreaks frequently and the scope is expanded, drinking water sources are also threatened by cyanobacteria Shui Hua. More and more attention has been paid to the safety of drinking water. During Shui Hua's period, a large number of algae cells and their toxic metabolites caused the water quality to deteriorate sharply. Microcystis aeruginosa is an important dominant algae species in the water body of cyanobacteria Shui Hua, and is also the main toxic algal species of microcystins. Most of the microcystins are concentrated in the cells, so, It is very important for drinking water plant to remove cyanobacteria cells completely and without damage. Coagulation and sedimentation is the core process in drinking water plant, which can effectively remove cyanobacteria cells from drinking water. However, the effect of coagulation process on the cell integrity of cyanobacteria should be concerned. In this paper, polyaluminum ferric chloride coagulant was used to remove high density cyanobacteria cells from simulated raw water, and the optimum conditions of coagulation were investigated. The effects of coagulation process and algal flocs stacking process on the integrity of cyanobacteria cells under optimal coagulation conditions were studied. The changes of extracellular algal toxins and three dimensional fluorescence matrix spectra were obtained by scanning electron microscopy and fluorescence microscopy. The condition of anaerobic degradation of microcystins in algae flocs was also investigated. Microcystins released from algal flocs could not cause secondary pollution. The main research result was: 1) treatment of high algal water with simulated Shui Hua cell concentration of about 2 脳 10 ~ 6 cells/mL. The optimization results of coagulation conditions are: 1: PAFC dosage 15 mg / L; fast stirring speed 250 r / min, time 1 min slow stirring speed 40 r / min, time 20 mins; static sedimentation time 20 mins; removal rate of cyanobacteria cells up to 99.2%) coagulant dosage, fast stirring rate. Slow stirring rate and slow stirring time had a great effect on the removal rate of cyanobacteria cells. The effect of fast stirring time on the removal rate of cyanobacteria cells was not obvious in the range of this experiment. After coagulation and sedimentation, the cyanobacteria cells were completely removed from the simulated water samples. It was transferred to the floc. Mechanical agitation and optimal dosage of PAFC did not cause obvious damage of cyanobacteria cells. (4) the concentration of extracellular microcystins was lower within 12 days after the accumulation of algal flocs. But the normal growth state of cyanobacteria cells was inhibited, which reduced the release of organic matter. 5) the algal flocs were treated by anaerobic treatment. At the initial pH of 8 and temperature of 35 鈩，

本文編號(hào)：1584792