摘 要

随着规模化养殖业的迅猛发展，高氨氮养殖废水的污染已成为污水处理领域亟需解决的问题。物理化学技术、传统生物技术均存在去除效果不彻底、易引起二次污染和操作成本高等缺点，化学絮凝-生物除氮复合技术以操作成本低、工艺流程简单、除氮效率高等优点，逐渐被广泛关注。

本研究从某奶牛养殖场废水中、在氨氮值400 mg/L的培养基中分离驯化出了菌GN1~GN6，并研究了它们在短程硝化反硝化条件下的脱氮效果，验证中8 d内GN5除氮率最高为49 %，测绘了其48 h内生长曲线，并从盐度、pH值和起始氨氮值三个方面对菌株进行了优化处理；然后将除氮效果最好的两株菌GN5、GN6进行了氨氮值为200 mg/L驯化条件优化，筛出3株菌，与之前GN5、GN6另命名为SN1~SN5，并进行了配伍研究；将聚合FeCl₃、聚合AlCl₃、阳离子PAM、一般土应用到对废水的絮凝预处理中，分别研究其对氨氮和COD去除率；最后将化学絮凝预处理与生物脱氮相复合应用到脱氮处理中。研究表明：

（1）菌株的最佳盐度生长环境为1g/L，最佳生长pH值为10，最佳起始氨氮值小于100 mg/L，在此环境下48 h的除氮率分别是40 %、55 %和95 %。

（2）在菌株配伍中，SN-1 SN-4和SN-1 SN-5的配伍方式去除氨氮效果较好，在起始氨氮浓度为400 mg/L的培养基中48 h的除氮率达到40 %，高于单菌株48 h的除氮率。

（3）在絮凝剂实验中，其中3 %聚合AlCl₃脱氮效果最好，对氨氮和COD去除率分别是64 %和33 %。

（4）在应用中，使用3 %聚合AlCl₃对初始氨氮值为534 mg/L的原水进行预处理，氨氮值降到300 mg/L左右，再接入配伍后的菌株，根据优化结果调节菌株的生长环境的pH、补加碳源，最终氨氮去除率高达95 %，比不经过预处理的工艺节省了时间和50 %的碳源。

关键词：奶牛场养殖废水；高浓度氨氮；高效硝化菌；化学絮凝

Abstract

As large scale livestork production develop rapidly, the treatment of cows farm wastewater with high concentration of ammonia-nitrogen becomes more and more trickier. Physical-chemical process and traditional biological denitrification process have the weakness that its denitrification rate is low, easy to cause secondary pollution and high cost and less application. Chemical flocculation-biological nitrogen removal technology which has low operation cost, simple process, high efficiency of nitrogen removal has been widely concerned.

This study isolated bacteria in the medium of ammonia nitrogen value of 400 mg/L from cows farm wastewater and named GN1~GN6, and aimed at studying the nitrogen removal under the shortcut nitrification-denitrification condition. The highest nitrogen removal rate was 49 % in 8 days, and the growth curve of GN5 in 48 hours was also verified. The optimal treatment of the strain from salinity, pH and initial ammonia nitrogen was carried out. Then the two strains of GN5 and GN6, which had the best nitrogen removal efficiency, were optimized for 200 mg/L acclimation conditions, and 3 strains were screened out. GN5, GN6 and the 3 strains was named SN1~SN5, and the compatibility that work together was studied; PFC, PAC, cationic PAM and the general soil had been applied to the flocculation pretreatment of wastewater, respectively, to study the removal rate of ammonia nitrogen and COD. In the end, chemical flocculation pretreatment and biological denitrification were applied to the treatment of nitrogen removal.

(1) The optimal salinity growth environment of the strain was 1 g/L; The optimum growth pH value 10; The optimum initial ammonia nitrogen value was less than 100 mg/L; In those conditions, the nitrogen removal rate in 48 h was 40 %, 55 % and 95 %.

(2) In compatibility of strains worked together, the SN-4 SN-1 and SN-5 SN-1 were used to remove the ammonia nitrogen better. The nitrogen removal rate in 48 h in the medium with the initial ammonia nitrogen concentration was 400 mg/L was 40 %, which was higher than that of the single strain in 48 h.

(3) In the experiment of flocculant, the removal rate of 3 % AlCl3 was best, and the removal rate of ammonia nitrogen and COD was 64 % and 33 % respectively.

(4) In the application, using 3 % PAC for raw water pretreatment which the initial ammonia nitrogen value was 534 mg/L, the ammonia value reduced to about 300 mg/L, then access the compatibility of strains and to adjust the pH of the environment for the growth of strains according to results of optimization, adding carbon source, ammonia removal rate as high as 95 % than not after pretreatment process and saves time and 50 % of the carbon source.

Key words: cows farm wastewater; high concentration of ammonia-nitrogen; nitrifying bacteria; chemical flocculatio

目录

摘要 I

Abstract II

1 绪论 1

1.1 引言 1

1.1.1 奶牛养殖废水的来源 1

1.1.2奶牛养殖废水的水质特点及危害 1

1.2 奶牛养殖废水处理技术简介 2

1.2.1 物理化学方法 2

1.3生物脱氮技术简介 3

1.3.1 传统的生物脱氮 4

1.3.2 新型生物脱氮工艺 6

1.4化学絮凝-生物脱氮复合技术简介 6

1.4.1 化学絮凝机理简介 7

1.5 本课题的研究内容及意义 8

2 高效硝化菌的筛选分离 9

2.1 实验材料与方法 9

2.1.1 养殖废水来源 9

2.1.2 培养基及试剂 9

2.2 标准曲线的测定 10

2.2.1 氨氮标准曲线的测定 10

2.2.2 低量程（测定上限250 ml/L）COD标准曲线的测定 11

2.3 高效硝化菌的筛选分离 13

2.3.1 硝化菌的驯化 13

2.3.2 硝化菌的筛选分离 13

2.3.3 硝化菌的去氨氮能力验证 13

2.4 实验结果与讨论 13

2.4.1 硝化菌的驯化结果 13

2.4.2 硝化菌的筛选分离 13

2.4.3 硝化菌的去氨氮能力验证 14

3 高效硝化菌株去除氨氮的条件优化 17

3.1 菌株生长曲线的测定 17

3.1.1 实验方法 17

3.1.2 实验结果与讨论 17

3.2 菌株驯化条件改变 18

3.2.1 实验方法 18

3.2.2 实验结果与讨论 18

3.3 培养基起始盐度对菌株SN-1去除氨氮的影响 18

3.3.1 实验方法 18

3.3.2 实验结果与讨论 18

3.4 培养基起始pH值对菌株SN-1去除氨氮的影响 20

3.4.1 实验方法 20

3.4.2 实验结果与讨论 20

3.5 培养基起始氨氮值对菌株SN-1去除氨氮的影响 22

3.5.1 实验方法 22

3.5.2 实验结果与讨论 22

3.6 菌株配伍脱氨氮实验 23

3.6.1 实验方法 23

3.6.2 实验结果与讨论 24

3.7 硝化菌的生理化实验 25

3.7.1 吲哚实验 25

3.7.2 乙酰甲基甲醇实验 26

4 高效硝化菌在奶牛养殖废水中的应用 27

4.1 化学絮凝法对奶牛养殖废水预处理效果 27

4.1.1 实验材料与方法 27

4.1.2 实验结果与分析 28

4.2 化学絮凝-生物脱氮在奶牛养殖废水中的应用 29

4.2.1 实验方法 29

4.2.2 实验结果与分析 29

5 总结与展望 31

参考文献 32

致谢 34

1 绪论

1.1 引言

近年来，随着人民生活水平的提高，对畜牧产品的需求也随之增加，如表1.1(表中数据来自中国农业年鉴)所示，牧业产值2005年是1970年的120倍，是1990年的4．26倍^[1]。

表1.1 近三十年我国畜牧总产值增长情况表

近年来养殖业的发展有两个较为明显的特点：

(1)养殖业的规模化