固定化微生物對酚類物質(zhì)的降解性能研究
發(fā)布時(shí)間：2018-09-05 06:17
【摘要】：含酚廢水是一種普遍存在并對人類生命安全危害嚴(yán)重的工業(yè)廢水。因此，含酚廢水的處理引起了人們高度重視，并逐步形成了以物理法、化學(xué)法、生物法為代表的三大處理技術(shù)。其中生物法中的固定化微生物法因微生物密度高且流失少、反應(yīng)速度快、耐毒害能力強(qiáng)、微生物代謝產(chǎn)物容易分離、處理設(shè)備簡單等特點(diǎn)得到廣泛應(yīng)用。 本論文采用以苯酚和對硝基苯酚為唯一碳源的無機(jī)鹽培養(yǎng)基分別篩選出對苯酚和對硝基苯酚有良好降解能力的菌株FG-01和FG-02，經(jīng)菌株鑒定后，用固定化材料鈣基膨潤土和羧甲基纖維素鈉（CMC）將其分別固定，研究固定化微生物的降酚性能。主要研究內(nèi)容如下： 1、菌株FG-01和菌株FG-02的16SrDNA序列同源性分析結(jié)果表明：菌株FG-01與菌株Bacillus pumilus (DQ907936，芽孢桿菌屬)相似性100%，菌株FG-02與菌株Aeromicrobium erythreum (GU186112，氣微菌屬)相似性為84.3%。 2、研究了固定化微生物顆粒的制備條件，并對其結(jié)構(gòu)進(jìn)行了表征，同時(shí)進(jìn)行了固定化微生物顆粒穩(wěn)定性研究。正交實(shí)驗(yàn)結(jié)果表明：固定化微生物顆粒制備的最佳條件為AlCl3濃度為1%，鈣基膨潤土的含量為5%，，菌懸液的量為20%，交聯(lián)時(shí)間為1h，鈣基膨潤土的粒徑為100目，CMC含量為3%。最優(yōu)條件下制得的固定化微生物顆粒對苯酚的降解率為93.22%（苯酚初始濃度為50mg/L），對對硝基苯酚的降解率為74.28%（對硝基苯酚初始濃度為10mg/L）。通過掃描電鏡SEM對固定化顆粒結(jié)構(gòu)進(jìn)行表征，結(jié)果表明：材料內(nèi)部的褶皺結(jié)構(gòu)較多，鈣基膨潤土和CMC結(jié)合增大了材料內(nèi)部的比表面積，非常有利于微生物在材料內(nèi)部生長。通過探究固定化微生物顆粒的儲存穩(wěn)定性和重復(fù)利用性，結(jié)果表明：固定化微生物顆粒在4℃保存40d時(shí)，其苯酚降解率仍可達(dá)90%以上，其被連續(xù)使用了9批次時(shí)，苯酚降解率仍有88%以上。 3、研究了固定化單一微生物顆粒對苯酚和對硝基苯酚的降解性能�？疾炝祟w粒投加量，初始濃度，溫度，降解時(shí)間對酚類物質(zhì)降解的影響。結(jié)果表明：固定化微生物顆粒降解酚類物質(zhì)的最佳投加量為0.23g/mL，最佳溫度為35℃。固定化FG-01顆粒耐苯酚的最高濃度為1000mg/L，而固定化FG-02顆粒耐對硝基苯酚的最高濃度僅為150mg/L。 4、對游離菌、CMC-鈣基膨潤土固定化顆粒、CMC-鈣基膨潤土固定化微生物顆粒、CMC固定化微生物顆粒的降酚性能進(jìn)行對比研究，結(jié)果表明：各系統(tǒng)對酚類物質(zhì)的降解效果為：CMC-鈣基膨潤土固定化微生物顆粒CMC-鈣基膨潤土固定化顆粒游離菌CMC固定化微生物顆粒，即復(fù)合載體共固定化微生物顆粒對酚類物質(zhì)的降解率最高。 5、研究了外加碳源對固定化單一微生物降解酚類物質(zhì)的影響，結(jié)果表明：當(dāng)對硝基苯酚濃度50mg/L時(shí)，對固定化FG-01顆粒降解苯酚基本上沒有影響，僅延長了降解平衡時(shí)間。當(dāng)對硝基苯酚初始濃度50mg/L時(shí)，抑制作用逐漸明顯，當(dāng)對硝基苯酚初始濃度為100mg/L時(shí)，固定化FG-01顆粒降解苯酚的降解率僅為28.95%。同時(shí)固定化FG-01顆粒內(nèi)部的微生物FG-01也可以以對硝基苯酚為共代謝碳源，當(dāng)對硝基苯酚濃度為30mg/L時(shí)，對對硝基苯酚的同時(shí)降解率達(dá)到最大，為55.45%。當(dāng)對硝基苯酚濃度逐漸增大時(shí)，降解率逐漸下降；固定化FG-02顆粒的微生物FG-02可以以苯酚和對硝基苯酚作為共代謝碳源，而對硝基苯酚的毒性較對苯酚的大，并且對硝基苯酚的降解途徑較苯酚的復(fù)雜，故FG-02對苯酚的利用率較對硝基苯酚的利用率大。 6、研究了固定化復(fù)合微生物對混合廢水降解的影響，結(jié)果表明：復(fù)合載體內(nèi)部包埋的微生物FG-01/FG-02比例為4:2時(shí)，固定化復(fù)合微生物顆粒對苯酚和對硝基苯酚均有較高的降解率。
[Abstract]:Phenolic wastewater is a kind of industrial wastewater which is ubiquitous and harmful to human life. Therefore, the treatment of phenolic wastewater has attracted great attention and three major treatment technologies have been gradually formed, including physical, chemical and biological methods. It has been widely used for its rapid reaction, high toxicity resistance, easy separation of microbial metabolites and simple treatment equipment.
In this paper, the strains FG-01 and FG-02 with good degradability of p-nitrophenol and p-nitrophenol were screened out by using inorganic salt medium with phenol and p-nitrophenol as the sole carbon source. After identification of the strains, they were immobilized with calcium-based bentonite and sodium carboxymethylcellulose (CMC) respectively to study the phenol-reducing effect of immobilized microorganisms. The main research contents are as follows:
1. The 16S rDNA sequence homology analysis of strain FG-01 and FG-02 showed that the similarity between strain FG-01 and Bacillus pumilus (DQ907936, Bacillus) was 100%, and that between strain FG-02 and Aeromicrobium erythreum (GU186112, Aeromicrobium) was 84.3%.
2. The preparation conditions of immobilized microbial particles were studied, and their structures were characterized. The stability of immobilized microbial particles was also studied. The results of orthogonal experiment showed that the optimum conditions for the preparation of immobilized microbial particles were 1% AlCl3, 5% Ca-bentonite, 20% suspension and 1 h crosslinking time. The particle size of Ca-bentonite was 100 mesh and the CMC content was 3%. Under the optimum conditions, the immobilized microbial particles could degrade phenol 93.22% (the initial concentration of phenol was 50mg/L) and p-nitrophenol 74.28% (the initial concentration of p-nitrophenol was 10mg/L). The structure of the immobilized particles was characterized by SEM. The results show that there are many folds in the material, and the combination of calcium-based bentonite and CMC enlarges the specific surface area of the material, which is beneficial to the growth of microorganisms in the material. The rate of hydrolysis is still more than 90%. When it is used in 9 batches, the phenol degradation rate is still over 88%.
3. The degradation of phenol and p-nitrophenol by immobilized single microbial particles was studied. The effects of dosage, initial concentration, temperature and degradation time on the degradation of phenols were investigated. The results showed that the optimum dosage of immobilized microbial particles was 0.23g/mL, and the optimum temperature was 35 C. FG-01 particles were immobilized. The highest concentration of phenol-resistant granules was 1000 mg/L, while the highest concentration of p-nitrophenol-resistant immobilized FG-02 granules was only 150 mg/L.
4. The phenol-reducing properties of free bacteria, CMC-Ca-bentonite immobilized particles, CMC-Ca-bentonite immobilized microbial particles and CMC immobilized microbial particles were compared. The results showed that the phenolic substances were degraded by each system as follows: CMC-Ca-bentonite immobilized microbial particles CMC-Ca-bentonite immobilized particles were free. Bacterial CMC immobilized microbial particles, i.e. composite carrier co-immobilized microbial particles, had the highest degradation rate of phenolic substances.
5. The effect of carbon source on the degradation of phenolic substances by immobilized single microorganism was studied. The results showed that when the concentration of p-nitrophenol was 50mg/L, the degradation of phenol by immobilized FG-01 particles was almost unchanged, but the equilibrium time was prolonged. At the initial concentration of 100mg/L, the degradation rate of phenol by immobilized FG-01 particles was only 28.95%. At the same time, the microorganism FG-01 in the immobilized FG-01 particles could also use p-nitrophenol as co-metabolic carbon source. When the concentration of p-nitrophenol was 30mg/L, the degradation rate of p-nitrophenol was the highest, which was 55.45%. The degradation rate of FG-02 decreased gradually with the increase of FG-02 particles. The immobilized FG-02 particles could use phenol and p-nitrophenol as co-metabolic carbon sources, and the toxicity of FG-02 to nitrophenol was greater than that to p-phenol, and the degradation pathway of FG-02 to nitrophenol was more complex than that to phenol, so the utilization rate of FG-02 to phenol was higher than that to p-nitrophenol.
6. The effect of immobilized composite microorganism on the degradation of mixed wastewater was studied. The results showed that the immobilized composite microorganism particles had higher degradation rate of phenol and p-nitrophenol when the ratio of FG-01/FG-02 was 4:2.
【學(xué)位授予單位】：太原理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：X172;X703
[Abstract]:Phenolic wastewater is a kind of industrial wastewater which is ubiquitous and harmful to human life. Therefore, the treatment of phenolic wastewater has attracted great attention and three major treatment technologies have been gradually formed, including physical, chemical and biological methods. It has been widely used for its rapid reaction, high toxicity resistance, easy separation of microbial metabolites and simple treatment equipment.
In this paper, the strains FG-01 and FG-02 with good degradability of p-nitrophenol and p-nitrophenol were screened out by using inorganic salt medium with phenol and p-nitrophenol as the sole carbon source. After identification of the strains, they were immobilized with calcium-based bentonite and sodium carboxymethylcellulose (CMC) respectively to study the phenol-reducing effect of immobilized microorganisms. The main research contents are as follows:
1. The 16S rDNA sequence homology analysis of strain FG-01 and FG-02 showed that the similarity between strain FG-01 and Bacillus pumilus (DQ907936, Bacillus) was 100%, and that between strain FG-02 and Aeromicrobium erythreum (GU186112, Aeromicrobium) was 84.3%.
2. The preparation conditions of immobilized microbial particles were studied, and their structures were characterized. The stability of immobilized microbial particles was also studied. The results of orthogonal experiment showed that the optimum conditions for the preparation of immobilized microbial particles were 1% AlCl3, 5% Ca-bentonite, 20% suspension and 1 h crosslinking time. The particle size of Ca-bentonite was 100 mesh and the CMC content was 3%. Under the optimum conditions, the immobilized microbial particles could degrade phenol 93.22% (the initial concentration of phenol was 50mg/L) and p-nitrophenol 74.28% (the initial concentration of p-nitrophenol was 10mg/L). The structure of the immobilized particles was characterized by SEM. The results show that there are many folds in the material, and the combination of calcium-based bentonite and CMC enlarges the specific surface area of the material, which is beneficial to the growth of microorganisms in the material. The rate of hydrolysis is still more than 90%. When it is used in 9 batches, the phenol degradation rate is still over 88%.
3. The degradation of phenol and p-nitrophenol by immobilized single microbial particles was studied. The effects of dosage, initial concentration, temperature and degradation time on the degradation of phenols were investigated. The results showed that the optimum dosage of immobilized microbial particles was 0.23g/mL, and the optimum temperature was 35 C. FG-01 particles were immobilized. The highest concentration of phenol-resistant granules was 1000 mg/L, while the highest concentration of p-nitrophenol-resistant immobilized FG-02 granules was only 150 mg/L.
4. The phenol-reducing properties of free bacteria, CMC-Ca-bentonite immobilized particles, CMC-Ca-bentonite immobilized microbial particles and CMC immobilized microbial particles were compared. The results showed that the phenolic substances were degraded by each system as follows: CMC-Ca-bentonite immobilized microbial particles CMC-Ca-bentonite immobilized particles were free. Bacterial CMC immobilized microbial particles, i.e. composite carrier co-immobilized microbial particles, had the highest degradation rate of phenolic substances.
5. The effect of carbon source on the degradation of phenolic substances by immobilized single microorganism was studied. The results showed that when the concentration of p-nitrophenol was 50mg/L, the degradation of phenol by immobilized FG-01 particles was almost unchanged, but the equilibrium time was prolonged. At the initial concentration of 100mg/L, the degradation rate of phenol by immobilized FG-01 particles was only 28.95%. At the same time, the microorganism FG-01 in the immobilized FG-01 particles could also use p-nitrophenol as co-metabolic carbon source. When the concentration of p-nitrophenol was 30mg/L, the degradation rate of p-nitrophenol was the highest, which was 55.45%. The degradation rate of FG-02 decreased gradually with the increase of FG-02 particles. The immobilized FG-02 particles could use phenol and p-nitrophenol as co-metabolic carbon sources, and the toxicity of FG-02 to nitrophenol was greater than that to p-phenol, and the degradation pathway of FG-02 to nitrophenol was more complex than that to phenol, so the utilization rate of FG-02 to phenol was higher than that to p-nitrophenol.
6. The effect of immobilized composite microorganism on the degradation of mixed wastewater was studied. The results showed that the immobilized composite microorganism particles had higher degradation rate of phenol and p-nitrophenol when the ratio of FG-01/FG-02 was 4:2.
【學(xué)位授予單位】：太原理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：X172;X703
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 吳勇民;李甫;黃咸雨;胡和兵;;含酚廢水處理新技術(shù)及其發(fā)展前景[J];環(huán)境科學(xué)與管理;2007年03期
2 肖亦;鐘飛;潘獻(xiàn)曉;;固定化微生物技術(shù)在廢水處理中的應(yīng)用研究進(jìn)展[J];環(huán)境科學(xué)與管理;2009年06期
3 左鵬;于少明;楊杰茹;章t熱
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