蓝藻腐烂特性及其加压结团絮凝沉淀浓缩技术研究

发布时间：2018-01-15 07:36

本文关键词：蓝藻腐烂特性及其加压结团絮凝沉淀浓缩技术研究　出处：《扬州大学》2017年硕士论文　论文类型：学位论文

更多相关文章： 腐烂特性 加压 结团絮凝 混凝沉淀 浓缩

【摘要】：为了提高蓝藻浆浓缩效率,降低能耗,采用外加压力压破蓝藻气囊,使蓝藻失去气囊浮力易于沉淀分离。本文主要关注并研究了蓝藻的腐烂特性以及蓝藻加压后结团絮凝沉淀浓缩效果,并在此基础上进行加压加压结团絮凝沉淀浓缩湖泊蓝藻工艺动态试验,从而得到一种安全、高效、经济的蓝藻水分离处理工艺。(1)研究了不同温度下蓝藻的腐烂过程,将蓝藻浆分别放置于25℃、30℃、35℃的恒温培养箱中培养,间隔一定时间观察蓝藻性状,取样测定蓝藻残余叶绿素量,用于表征蓝藻腐烂程度。测定蓝藻过滤液中的TOC、TN、TP等水质指标,表征蓝藻腐烂、藻细胞破烂后向水中释放污染物的量,间接反映蓝藻腐烂程度。当培养温度为25℃时,蓝藻腐烂度和污染物释放量在开始培养后的108h内并没有明显的变化,而在随后的96h内腐烂度和污染物释放量开始逐渐增大,整个腐烂过程较慢且需要7.5d才能完全腐烂;当培养温度为30℃时,蓝藻腐烂度和污染物释放量在开始培养后的12h内有较大幅度的变化,之后的36h内变化减小随后蓝藻腐烂度和污染物释放量重新增大,整个腐烂过程较快只需要3.5d就完全腐烂;当培养温度为35℃时,蓝藻腐烂度和污染物释放量在开始培养后的24h内就快速增高直至稳定,整个腐烂过程极快仅需1d就完全腐烂。(2)通过静态实验研究了不同腐烂程度蓝藻浆混凝沉淀性能,将蓝藻浆分别放置于25℃、30℃、35℃的恒温培养箱中培养,间隔一定时间取藻液进行加压混凝沉淀浓缩实验,取上清液测定浊度、TN、TP、CODcr以及残余叶绿素和藻毒素量等水质指标,最终得出在不同腐烂程度下的最佳加药量。通过静态实验发现,在处理新鲜藻浆(腐烂度在30%以下)时随着投药量的增加,新鲜藻浆经过混凝沉淀后各污染物释放量以及残余叶绿素和藻毒素量是逐步降低的,最终确定当PAC投加量与干藻质量比为1/15以及PAM投加量与干藻质量比为1/1000时为最佳投加量;当蓝藻浆开始腐烂(腐烂度在30%到60%)时,最终确定将PAC投加量与干藻质量比调整到1/5以及将PAM投加量与干藻质量比调整为1/800能明显提高出水水质;在处理陈腐藻浆(腐烂度在60%以上)时,最终确定当PAC投加量与干藻质量比为1/1.6以及PAM投加量与干藻质量比为1/667时为最佳投加量。(3)通过动态实验研究了结团絮凝沉淀浓缩新鲜蓝藻和陈腐蓝藻浆的工艺方法和效果,先采用双罐并联加压装置对藻浆进行加压后接结团絮凝沉淀池,待装置稳定运行一段时间后取出水水样测定浊度、叶绿素a、TN、TP、高锰酸盐指数以及底泥的含水率。通过动态实验发现,在处理新鲜藻浆时,选定PAC最佳投加量为干藻质量的1/20以及PAM的最佳投加量为干藻质量的1/1500处理效果最佳。在最佳投药量下继续实验,发现藻水分离动态实验各项指标是优于静态实验的,出水浊度普遍小于6NTU、叶绿素a浓度小于7mg·m-3,藻泥的含水率小于97%,但是要控制原藻浆的含水率在99%以上,并且在99.4%时的处理效果最佳;在处理陈腐藻浆时,选定PAC最佳投加量为干藻质量的1/1.5以及PAM的最佳投加量为干藻质量的1/300处理效果最。继续研究我们发现需要将上升流速控制在2m·h-1的范围内以达到最佳的出水要求,在最佳投药量下,为了达到最佳的处理效果,需要控制原藻浆的含水率在99.2%以上,并且在99.4%时的处理效果达到最佳。
[Abstract]:In order to improve the blue-green algae slurry concentrating efficiency, reduce energy consumption, the external pressure crushed cyanobacteria balloon, the cyanobacteria lose buoyancy force to precipitation separation. This paper focuses on the research and the decay characteristics and cyanobacteria cyanobacteria pressed pellet flocculation precipitation concentration effect, and on the basis of the pressure pressure pellet flocculation sedimentation process dynamics of cyanobacteria the test, so as to obtain a safe, efficient and economical algae water separation process. (1) studied the decomposition process under different temperature of cyanobacteria, the blue-green algae slurry were placed in 25 degrees, 30 degrees, 35 degrees thermostatic culture box, a certain time interval to observe the cyanobacteria traits, sampling and determination of residual cyanobacteria chlorophyll was used to characterize the extent of decay of cyanobacteria. Determination of cyanobacteria filtrate in TOC, TN, TP and other water quality indicators, characterization of cyanobacteria algal cells after decay, broken the amount of pollutants released into the water, indirect Reflect the decay degree. When cyanobacteria culture temperature was 25, and no obvious changes of cyanobacterial decay degree and pollutant emissions at the start of training after 108h, while the decay degree and pollutants in the subsequent 96h release began to increase gradually, the whole process of decay is slow and requires 7.5d to fully decay when the culture temperature; is 30 degrees centigrade, and pollutant emissions of putrefactive cyanobacteria in began to develop 12h after a larger variation, then the putrefactive cyanobacteria degree and pollutant emissions to increase decrease after the change in 36h, the whole process of decay faster 3.5D only need to completely decay; when the culture temperature is 35 degrees centigrade, algae decay degree and pollutant emissions at the start of training 24h after quickly increased until a stable, the whole process of fast decay only 1D completely decomposed. (2) through the static experiments of different decay degree of blue-green algae slurry coagulation The performance of blue-green algae slurry were placed in 25 degrees, 30 degrees, 35 degrees thermostatic culture box, a certain time interval from algae liquid pressure coagulation sedimentation experiment concentrated supernatant, determination of turbidity, TN, TP, CODcr and residual chlorophyll and microcystin amount and other water quality indicators in the different degree of decay under the optimum dosage. Through static experiments, in the processing of fresh algae slurry (decay degree below 30%) with the increase of drug dosage, fresh algae slurry after coagulation and sedimentation of various pollutants emissions and residual chlorophyll and microcystins amount is gradually reduced, and ultimately determine when the dosage of PAC and dry algae the mass ratio of 1/15 and PAM dosage and the dry algal mass ratio 1/1000 was the optimal dosage; when the algae slurry begins to rot (decay in 30% to 60%), and ultimately determine the dosage of PAC and dry algae mass ratio adjusted to 1/5 and the dosage of PAM and dry algae The mass ratio is adjusted to 1/800 can significantly improve the water quality; in the treatment of stale algae slurry (decay degree above 60%), and ultimately determine when the PAC dosage and the dry algal mass ratio of 1/1.6 and PAM dosage and the dry algal mass ratio 1/667 was the optimal dosage. (3) method and process the effect of dynamic experimental studies of pellet flocculation precipitation concentrated fresh cyanobacteria and stale cyanobacteria pulp, using double tank parallel pressurizing device for pressurizing the algae slurry after pellet flocculation sedimentation, turbidity determination, for the stable operation of the device after a period of time out of the water sample of chlorophyll a, TN, TP, permanganate index and sediment the rate of water content. Through dynamic experiments, in the processing of fresh algae slurry, selected the best dosage of PAC was 1/20 and the quality of the dried algae PAM dosage is the quality of the dried algae 1/1500 best. Continue the experiment at the optimum dosage, found water algae From the dynamic experiment indexes is better than the static experiment, the effluent turbidity is generally less than 6NTU, the chlorophyll a concentration less than 7Mg / M-3, water algae mud rate less than 97%, but to control the raw water algae slurry at a rate above 99%, and the best treatment effect in 99.4%; in the treatment of stale algae slurry, selected 1/300 the treatment effect is the best dosage of dried algae quality the best dosage of PAC was 1/1.5 and the quality of the dried algae PAM. We found that the need to continue to study the rise velocity control in the range of 2m - H-1 in order to achieve the best water requirements in the best dosage, in order to achieve the best treatment effect, need control of raw water algae slurry at a rate above 99.2%, and the treatment effect in 99.4% to achieve the best.

【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X524

【参考文献】