【作者】 黄学平；

【导师】 万金保；

【作者基本信息】 南昌大学 ， 环境科学与工程， 2018， 博士

【摘要】 利用养猪废水资源化培养能源微藻制备生物柴油,不但能够降低生物柴油的原材料生产成本、缓解能源短缺问题;而且可以利用养猪废水中的N和P等污染物、变废为宝,同时达到净化废水目的。本文主要进行藻在养猪废水中的生长适应性、养猪废水作为藻类培养基的可能性考察,从本地水环境筛选出能在养猪废水中优势生长、废水处理效果好、产油潜力大的目标藻种并进行18S rRNA基因鉴定,开展目标藻种生长好、产油潜力大与猪沼液处理效率高的耦联工艺优化研究等。具体研究内容及结论如下:1、基于SPSS软件的因子分析法,综合评价本地藻种（小球藻）与外购藻种（四尾栅藻、微囊藻）在养猪废水水质中的生长适应性、不同处理阶段的养猪废水水质成份作为藻类培养基的可能性及藻对外界环境温度变化等的适应能力。结果表明:试验用养猪场水样中原水的COD（4500mg/L）、NH₃-N（250mg/L）、TN（210²70mg/L）、TP（36mg/L）营养成份较适合藻生长;试验所用藻种中,小球藻藻细胞繁殖快、生长状态好、生长的综合适应能力表现为最强,能在养猪废水中生长成为优势藻种。2、从本地水环境取含藻混合液,按形态学观察、判断其主要含有小球藻等6类藻;经进一步分离、提存、扩大培养,按混合和单一藻种分别接种到猪沼液中进行“瓶法”培养;进行藻的生物量观测,利用origin8.5软件中的Slogistic2模型,对各类藻的生长情况进行非线性模拟,结果表明:两种（混合藻种、单一藻种）培养条件下,6类藻种中小球藻的μ_max及B_f均取得最大值,说明小球藻在养猪沼液中的生长适应性强、生长速度快、能优势生长;对6类藻种油脂的含量水平及产油潜力进行比对分析,结果显示:小球藻粗脂肪百分含量p%、总脂产量、油脂产率均最大,说明小球藻的产油潜力最大;对比6类藻种培养系统中的沼液水质指标的变化,发现:至试验培养终期,小球藻培养系统中的沼液其COD、NH₃-N、TP的浓度值最低、去除率最高,说明小球藻对培养系统中的沼液水质净化效果最好;因此确认小球藻是适应养猪废水培养环境能力强、能优势生长、产油潜力大、对沼液水质净化效果好的目标藻种筛选对象。将分离提纯得到的目标小球藻藻株IS117和IS118进行18S rRNA基因测序;将两序列上传到美国生物信息中心（NCBI）的基因数据库（GenBank）,获得序列登录号分别为KP201572和KP201573;用NJ和MP法构建系统发育进化树,最后鉴定两株藻株为Eukaryota,Viridiplantae,Chlorophyta,Trebouxiophyceae,Chlorellales,Chlorellaceae,Chlorella.3、设计制作猪沼液处理耦合培养小球藻的系列工艺系统,研究分析沼液处理效果、藻生长与产油潜力性能,发现:从沼液处理效果来看,BCO-SBBR-APBR藻菌协同培养处理系统的CODcr、NH₃-N、TP的去除率分别为74.8%、91%、85.4%,均为最高,即其沼液处理效果在所设计的系列工艺系统中是最好的。按稳定期藻性能指标,BCO-SBBR-APBR培养处理系统内的藻生长最好,藻细胞密度、总脂产量、油脂产率分别为15.61×10⁶cells/mL、0.495g·L^-1、0.062g·L^-1·d^-1,均取得最大值,说明该系统培养环境最适合藻的生长并能充分激发藻的产油潜力;居其后的BCO-SBBR-APBR藻菌协同培养处理系统则分别为11.06×10⁶cells/mL、0.368g·L^-1、0.037g·L^-1·d^-1,也表现出较好的产油潜力。综合来看,BCO-SBBR-APBR藻菌协同培养处理系统,既可使培养的小球藻生长好、产油潜力大,又能实现养猪废水水质高效净化,是最佳的养猪废水处理及资源化培养能源微藻的耦合系统。利用CFD对BCO、SBBR池内的曝气混合效果开展模拟分析,结果显示:池内藻-沼混合液混合较均匀、充分且死区占比很小;CFD模拟的反应器内部流场能很好地解释与印证本文试验现象即曝气可提高池内混合效果、改善废水处理效果及藻培养性能。4、基于响应面BBD优化设计原理、利用Design-Expert.V8.0.6软件,对藻泥共固定化颗粒的制备进行模拟优化,得到优化设计结果:复合固定化载体的最佳配合比（质量分数）为PVA=5.06%,SA=0.80%,CaCl₂=3.11%;藻、泥、载体的最佳体积配比为小球藻体积份数=1.03、活性污泥体积份数=2.14、载体体积份数=2.03。按优化设计研究结果,取小球藻体积份数=1.0、活性污泥体积份数=2.1、载体体积份数=2.0制备小球藻固定化颗粒、藻泥共固定化颗粒;将制备好的小球藻固定化颗粒、藻泥共固定化颗粒分批投入到BCO-SBBR-APBR实验装置中进行沼液处理研究,结果表明:BCO-SBBR-APBR固定藻菌培养处理系统对猪场沼液CODcr、TP、NH₃-N的去除效果都比BCO-SBBR-APBR固定藻培养处理系统更好。5、对本文所开展的各种工艺条件下的沼液去除效果进行对比,发现:从对CODcr、TP、NH₃-N的去除效果看,相较其它处理系统,BCO-SBBR-APBR固定藻菌培养处理系统表现为最优,其次为BCO-SBBR-APBR藻菌培养处理系统,再其次为BCO-SBBR-APBR固定藻培养处理系统。更多还原

【Abstract】 Cultivating energy microalgae for biodiesel with pig-breeding wastewater can not only reduce the production cost of biodiesel and ease energy shortage,but also fulfill the purpose of wastewater purification by making use of N and P from the wastewater.This paper aims at exploring the growth adaptability of algal and the possibility of taking pig-breeding wastewater as the culture medium of algae,then sorting out the algae species with advantageous growth and great oil-producing potential in local water environment.It conduct further researches on the optimization of coupled process system which is of high efficiency of pig biogas slurry treatment.The specific research is as follows:Employing factor analysis of SPSS software,the researcher conducted a comprehensive evaluation of the growth adaptability of local algae（Chlorella）and nonlocal algae（Scenedesmue quadricauda,Microcystis）in pig-breeding wastewater,and the possibility of wastewater in different treatment process as culture medium for algae,as well as different algae’s adaptability to surrounding temperature changes.The results showe that,first,COD（4500mg/L）,NH₃-N（250mg/L）,TN（210²70mg/L）and TP（36mg/L）in the original pig-breeding wastewater for experimental use were favorable for algae growth.Second,with high cell reproduction rate,vigorous growth conditions and good adaptability,the local algae used in the experiment,Chlorella,was considered as an advantageous species.The research employed some liquid for experimental use from local water environment,then observed and identified 6 kinds of algae including Chlorella.With further separation,purification and enlarged culture,mixture of different algae species and a single algae species were cultured in pig biogas slurry in the Erlenmeyer flasks.Then,biomass observation was conducted.Employing Slogistic2of origin8.5,non-linear simulation of different algae species were completed,and the results showed that theμ_max and B_f of Chlorella reached the maximum among the 6kinds of algae in both mixture and single condition.This indicates that Chlorella had good growth adaptability,fast growth rate,and great growth potential,thus led to advantageous growth.The results of comparative analysis of contents level of algal oil and oil-producing potential of the 6 kinds of algae indicates that Chlorella owned the highest oil content p%,total lipid yield and oil-producing rate among the 6 kinds of algae which means Chlorella had the greatest oil-producing potential.With the comparison of water quality index of biogas slurry collected from the flasks cultured the 6 kinds algae,it was found that the biogas slurry from the Chlorella culture flask had the lowest concentration of COD,NH₃-N,and TP,and the highest removal rate.Thus,Chlorella was considered as the target algal species with advantageous growth and high oil-producing ability,meanwhile it was the most adaptable to pig-breeding wastewater.The separated and purified Chlorellaceae sp.strains IS117 and IS118were carried out 18S rRNA genes sequences.The two sequences were uploaded to the gene database（GenBank）of the National Center for Biotechnology Information（NCBI）where two GenBank accession numbers KP201572 and KP201573 for their nucleotide sequences were given respectively.The neighbor-joining（NJ）method and the Maximum Parsimony（MP）method were used to construct phylogenetic trees.Above all,the sorted-out Chlorellaceae sp strains IS117 and IS118 can be identified as Eukaryota,Viridiplantae,Chlorophyta,Trebouxiophyceae,Chlorellales,Chlorellaceae,Chlorella.The research designed and made a coupled process for pig biogas slurry treatment based on Chlorella culturing,then observed,compared and analyzed different process systems’ability in treating biogas slurry,as well as the growth and oil-producing potential of different algae species.The results indicates that,judging from treatment result,the BCO-SBBR-APBR system for co-culture algal and fungi owned the highest removal rate in CODcr,NH₃-N,and TP,which is 74.8%,91%,85.4%and meant the best treatment effect.Judging from the performance index of algae in stationary phase,algae in the BCO-SBBR-APBR process grew best,moreover,the algae cell density,total lipid yield,and oil-producing rate of it reached highest,which is 15.61×10⁶cells/mL,0.495g·L^-1and 0.062g·L^-1·d^-1respectively.All these indicate that the environment of the BCO-SBBR-APBR process was the best for algal growth and could further promote algae’s oil-producing potential.In the BCO-SBBR-APBR system for co-culture algal and fungi,the index about the algae cell density,total lipid yield and oil-producing rate is 11.06×10⁶cells/mL,0.368g·L^-1and 0.037g·L^-1·d^-1 respectively and rank the second.Which meant the system is better for algal growth and could further promote algae’s oil-producing potential.Take together,the BCO-SBBR-APBR process system for co-culture algal and fungi was the best coupled process system for culturing algae of energy use in pig biogas slurry.The Chlorella cultured in it grew well and can produce much oil.Furthermore,the system may promote efficient purification and treatment of pig-breeding wastewater.Making use of the mixing effect of aeration produced by CFD with the reaction vessel of BCO-SBBR-APBR in simulation analysis,the simulation diagram of flow field showed that with a vessel of stabilized aeration,the algae and biogas could mix well,and the region of very small flow velocity occupied low percentage.This also indicated that the internal flow field of vessel simulated by CFD could explain and confirm the last experiment result that the vessel with better internally mixed condition worked better.Based on the BBD design principle of response surface methods,the experiment used Design-Expert.V8.0.6 to simulate and optimize immobilized particles of Chlorella and activated sludge and got the result.Composited immobilized carrier with the best mix proportion of PVA=5.06%,SA=0.80%,CaCl₂=3.11%.Meanwhile,composited carrier,algae and sludge with the best volume proportion:Chlorella volume fraction was 1.03;activated sludge volume fraction was 2.14;carrier volume fraction was 2.03.According to results of the research of optimizing preparation of immobilized particles,prepared immobilized particles of Chlorella,Chlorella-sludge with Chlorella volume fraction 1.0,activated sludge volume fraction 2.1,and carrier volume fraction 2.0.Then put the immobilized particles into biogas slurry getting from the BCO-SBBR-APB process system in batches and compared the treatment results.It was found that the BCO-SBBR-APBR process system for co-culture fixed algal and fungi had a better removal effect in CODcr、TP、NH₃-N than the BCO-SBBR-APBR process system for culture fixed algal.To conclude:compared the biogas slurry treatment results under all the technological conditions tested in the paper,considering the removal effect of CODcr、TP、NH₃-N in pig-breeding wastewater,the BCO-SBBR-APBR process system for co-culture fixed algal and fungi performed best,the BCO-SBBR-APBR process system for co-culture algal and fungi ranked the second,and then the BCO-SBBR-APBR process system for culture fixed algal was the third.更多还原