基于牛粪浓浆、沼液的光合细菌发酵及其应用研究

发布时间：2018-07-21 20:14

【摘要】：畜禽养殖的快速发展产生大量畜禽粪便,未经处置或处理不当的畜禽粪便对环境产生严重污染,影响人们生产生活,引发社会的强烈不满,一系列畜禽粪便引起的环境问题的爆发,严重阻碍我国畜禽养殖产业的可持续发展。目前我国集约化畜禽养殖场对于粪便处理主要有两种方法。一种是畜禽粪便直接发酵制沼气,但剩余沼液属于高浓度污染物,依然存在去向难、运输难、储存难等问题。沼气是新能源的再利用,但不是解决畜禽粪污环保问题的措施。另一种是通过螺旋挤压机进行固液分离,将粪便中的干物质与液体分离开来,得到含水率小于65%的固体物质和液体浓浆。固体物质经发酵堆肥,制成有机肥料,技术已经成熟,但液体浓浆含水率高达90%,尤其是奶牛粪污的液体浓浆,呈胶体状态,难降解,难分离,仍为难处理污染物。一般情况牛粪浓浆水COD(50000-90000 mg/L)、SS(60000-70000 mg/L)都非常高,通常的污水处理技术如絮凝沉淀、厌氧生化、好氧生化等手段都难以处理这类污水。本论文以奶牛粪污固液分离后的浓浆污水、奶牛粪污沼气化处理后的沼液为处理对象,利用浓浆和沼液中丰富的有机物质作为培养基,进行光合细菌发酵及其应用研究。由于浓浆和沼液均呈现难降解、难分离的胶体状态,故本研究首先筛选出三种适用于牛粪浓浆的絮凝剂,将其固形物沉淀,降低其SS、浊度和色度,得到可作为光合细菌培养基的牛粪浓浆水上清液。同时将筛选的絮凝剂用于沼液处理。再将牛粪浓浆水上清液作为光合细菌培养基,探讨用不同絮凝剂处理浓浆水后得到的上清液对光合细菌生长的影响,分析不同接种量、光照、添加营养物质(醋酸钠、氯化铵)以及部分循环连续培养下光合细菌的生长趋势,用OD660值法检测和表征光合细菌相对含量。实验中将絮凝剂壳聚糖作用于光合细菌浓缩得到光合细菌凝胶。最后用筛选的絮凝剂在新希望青白江牧场进行试验,取得了令人满意的效果。按本研究方法大规模生产光合细菌菌液,作为叶面肥施用于烟草、洋葱和水稻,以考察其肥效。本硕士论文得到以下主要结论:(1)三种絮凝剂对牛粪水均能产生絮凝作用,三种絮凝剂对色度的降低均能达到94%,壳聚糖和絮凝剂JP-1对浊度的去除率均能达到99%。(2)经过絮凝剂JP-1处理后的牛粪浓浆水上清液、沼液上清液和沼液反渗透浓缩液为原料的培养基中,接种光合细菌,36 h后光合细菌均出现明显的快速生长现象,而用另外两种絮凝剂(絮凝剂LSR和壳聚糖)处理后的牛粪浓浆水清液作为培养基,无光合细菌生长现象。分析原因可能是牛粪浓浆水上清液中残留的絮凝剂LSR和絮凝剂壳聚糖对光合细菌的生长产生抑制作用。(3)本研究筛选出的絮凝剂JP-1同样适用于沼液处理,成功从沼液中絮凝分离得到上清液。此上清液同样可作为培养基原料来培养光合细菌。且沼液上清液通过反渗透处理可以降解为清水和浓缩液体。清水可达标排放,浓缩液体可作为培养基原料来培养光合细菌,成功解决沼液后续处理问题。(4)以絮凝剂JP-1处理后的牛粪浓浆水上清液为培养基,在温度为35.5℃、p H为7.67-7.98、接种量为10%(v:v),40 W白炽灯光照72 h的条件下培养光合细菌,其菌液吸光度可达到2.2以上。且在相同条件下,以牛粪浓浆水上清液为培养基可以进行光合细菌部分循环连续培养。在牛粪浓浆水上清液培养基中添加醋酸钠和氯化铵对光合细菌生长影响不大。(5)本研究将壳聚糖絮凝剂用于光合细菌浓缩沉降,形成光合细菌凝胶。壳聚糖用量为0.02%时,光合细菌沉降效率R最大可达98%。所得光合细菌凝胶避光保存6个月仍保持菌体活性,重新培养,得到吸光度为2.0的光合细菌菌液。(6)本研究方案用于牧场现场试验,成功分离牧场新产牛粪浓浆水,得到牛粪浓浆水上清液用于工厂培养光合细菌,得到吸光度平均值高于2.2的光合细菌菌液。将其施用于烟草、洋葱和水稻时,产量分别增加20.8%、30.0%和5.6%。以奶牛粪污固液分离后的浓浆污水、奶牛粪污沼气化处理后的沼液为原料的光合细菌培养方法经济可行,具有广阔的应用前景。
[Abstract]:The rapid development of livestock and poultry production produces a large number of livestock and poultry excrement, untreated or untreated livestock and poultry manure seriously pollute the environment, affect people's production and life, cause a strong social discontent, and a series of environmental problems caused by livestock and poultry manure, which seriously impede the sustainable development of livestock and poultry industry in China. There are two main methods for the treatment of livestock and poultry farms. One is the direct fermentation of livestock and poultry manure to make biogas, but the residual methane is a high concentration of pollutants. There are still difficulties, difficult transportation and difficult storage. Biogas is the reutilization of new energy, but it is not a solution to environmental protection of livestock and poultry. The other is through the spiral. The extruder separates the solid liquid from the liquid and separates the dry matter from the liquid. The solid substance and liquid slurry with water content less than 65% are obtained. The solid substance is made into organic fertilizer by fermented composting, and the technology has been mature, but the water content of the liquid is up to 90%, especially the liquid thick pulp of milk cow dung, which is colloid, difficult to degrade and difficult to divide. In general, the COD (50000-90000 mg/L) and SS (60000-70000 mg/L) of cow dung are very high. The usual sewage treatment techniques such as flocculation and sedimentation, anaerobic biochemistry, aerobic biochemistry and other means are difficult to deal with. After the biogas slurry and the rich organic matter in the slurry and the rich organic matter in the slurry as the medium, the photosynthetic bacteria fermentation and its application are studied. Because both the slurry and the slurry are difficult to degrade, the colloid state is difficult to separate. Therefore, three kinds of flocculants, which are suitable for the cow dung thickened pulp, are first screened, and their solids are precipitated and the SS is reduced. Turbidity and chromaticity, the supernatant of cow dung, which can be used as the medium of photosynthetic bacteria, was obtained. At the same time, the selected flocculants were used in the treatment of biogas slurry. Then the supernatant of cow dung concentrated water was used as the culture medium of photosynthetic bacteria. The effect of the supernatant on the growth of photosynthetic bacteria by different flocculants treated with concentrated water was discussed, and the different inoculation amounts were analyzed. Light, adding nutrients (sodium acetate, ammonium chloride) and the growth trend of photosynthetic bacteria under partial cyclic continuous culture, the relative content of photosynthetic bacteria was detected and characterized by OD660 value method. In the experiment, the flocculant chitosan was used to concentrate the photosynthetic bacteria to obtain photosynthetic bacteria gel. Finally, the selected flocculant was used in the new Qingbaijiang pasture. The following main conclusions were obtained as follows: (1) three flocculants could produce flocculating effect on cow dung water, and the three flocculants could reduce the chromaticity of the three flocculants. To 94%, the removal rate of the turbidity of the chitosan and flocculant JP-1 can reach 99%. (2) after the flocculant JP-1 treatment of the thickening water supernatant of the cow dung, the supernatant of the biogas liquid and the reverse osmosis solution of the biogas liquid as the medium. The photosynthetic bacteria are inoculated with the photosynthetic bacteria, and the photosynthetic bacteria after 36 h all have obvious rapid growth phenomenon, and the other flocculants are used for the other flocculants. The flocculant LSR and chitosan were treated as medium and no photosynthetic bacteria growth. The reason may be that the flocculant LSR and flocculant chitosan in the supernatant of cow dung can inhibit the growth of photosynthetic bacteria. (3) the flocculant of this study is also suitable for the treatment of biogas slurry. The supernatant can also be used as medium to cultivate photosynthetic bacteria. The supernatant can be degraded into clear water and concentrated liquid by reverse osmosis. The clear water can reach the standard discharge, and the concentrated liquid can be used as medium to cultivate photosynthetic bacteria and successfully solve the subsequent treatment of biogas slurry. (4) in the medium of flocculant JP-1, the liquid supernatant of cow dung was treated as medium, at the temperature of 35.5 C, P H was 7.67-7.98, the inoculation amount was 10% (v:v), the 40 W incandescent light was cultured in 72 h, and the absorbance of the bacterial liquid could reach more than 2.2. And under the same condition, the light of the cow dung concentrated water supernatant could be used as the medium. The effect of sodium acetate and ammonium chloride on the growth of photosynthetic bacteria was little influenced by the addition of sodium acetate and ammonium chloride in the medium of strong water supernatant of cow dung. (5) the chitosan flocculant was used to concentrate the photosynthetic bacteria and formed a photosynthetic bacteria gel. When the dosage of chitosan was 0.02%, the maximum settlement efficiency of photosynthetic bacteria could reach to the maximum of 98%.. (5) The photosynthetic bacteria gel kept the bacterial activity for 6 months and recultured, recultured, and got the photosynthetic bacteria liquid of 2. (6) the study scheme was used in field test in pasture, and the new cow dung concentrated slurry was successfully separated from the pasture, and the strong liquid supernatant of cow dung was used in the factory to cultivate photosynthetic bacteria, and the average absorbance value was higher than 2.2. When applied to tobacco, onions and rice, the yield increased by 20.8%, 30% and 5.6%. respectively, with the separation of milk from cow dung and solid-liquid separation.
【学位授予单位】：四川师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X713

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