小球藻对絮凝预处理沼液的适应性及净化效果

采用聚合氯化铝P(AC)与聚丙烯酰胺(PAM)联合絮凝预处理+小球藻(FACHB-8)对猪场沼液进行处理.结果 表明,当PAC投加量为5g/L时,不同含量的PAM絮凝沼液,COD、NH3-N、TP和浊度的去除率分别为68.55％、36.84％、90.21％和6.48％.以絮凝预处理后的沼液作为培养液,经13d的培养,小...     

小球藻细胞对厌氧发酵沼液的净化效果研究

研究普通小球藻对养猪厂厌氧发酵沼液水质净化的效果,发现普通小球藻对发酵沼液中的总磷、亚硝态氮、氨氮和化学需氧量(COD)的最高去除率分别是82％、72％、85％和72％.结果表明,利用畜禽养殖厌氧发酵沼液培养藻类能够降低沼液中的氮磷元素含量并积累足够的有机质,是一种潜在的养猪场厌氧发酵沼液深度净化途径.     

小球藻在餐厨沼液中的培养条件及效果研究

针对餐厨沼液资源化处理的需求,开展小球藻培养实验,研究小球藻在预处理后的餐厨沼液中培养条件、耐盐量以及主要污染物的去除情况。结果表明：餐厨沼液稀释至20%的浓度,pH 6～7,接种量OD680=0.1,含盐量<0.5%为最佳培养条件,此时,小球藻能有效去除沼液中82%的氨氮,但小球藻对沼液中的COD去除能力较弱。餐厨沼液中氨氮的去除,将有效降低后续处理的难度。     

小球藻对奶牛场沼液处理能力及生物质生产的探究

为资源化处理奶牛场沼液、探究小球藻Chlorella vulgaris NIES-227对奶牛场沼液的处理能力以及生物质利用潜力,在柱式光生物反应器中利用小球藻处理沼液占比分别为25%、50%、75%和 100% 4种不同浓度的未灭菌污水。研究结果显示,各浓度污水中总氮、总磷和COD的去除率分别为36.0%～92.5%、42.8%～100%和6.9%～32.2%。在沼液占比为25%的污水中氮磷的去除率最高,氨氮、总氮和总磷的去除效率分别可达99.9%、91.0%和100%。微藻在低浓度沼液（25%～50%）中生长状态良好,在沼液占比为50%的污水中可获得最高生物质产率393.6 mg/(L·d)。但是在高浓度沼液（75%～100%）中微藻生长受到一定抑制,导致氮磷的去除效果变差。培养期间细菌的数量增长显著,促进了COD的去除。各浓度沼液生物质中总脂、总糖和蛋白质含量分别为13.2%～32.2%、12.3%～27.6%和16.2%～30.9%。实验数据表明,低浓度沼液能产生更多高能量组分的生物质,适合用作生物燃料的开发;高浓度沼液能产生含较多蛋白质的生物质,更适合用作动物饲料。     

沼液培养对小球藻的生长与生化组分的影响

本文对小球藻在牛粪厌氧发酵的沼液中生长模型和成分(蛋白质,脂肪,脂和脂肪酸组成成分)以及沼液浓度对小球藻中营养物质的去除率进行了研究。结果表明,对于不同稀释(2、10、100、1000)倍数的牛粪厌氧消化沼液,稀释倍数越高,小球藻的生长速率越慢。然而,在稀释2倍的牛粪沼液中,小球藻在培养初期停止生长。利用修正的Gompertz模型对小球藻在不同牛粪浓度下的生长特点做了很好的预测(R~20.837)。在稀释倍数为10、100、1000的牛粪沼液中,硝酸盐的去除率分别为75.6%、22.8%和100%。蛋白含量分别提高了29.4%、27.6%和31.4%。然而总脂肪酸含量随稀释倍数的增加而减小,由22.2%降到了17.9%。此外,在沼液培养的小球藻中,还发现了C16:0、C18:0、C18:1以及C18:2的脂肪酸组成。     

小球藻的沼液驯化、抗生素敏感性分析和选择标记筛选

通过平板划线法从河北的部分河流中筛选到5株小球藻,经奶牛养殖废水沼液驯化后得到优势藻株,通过18S rDNA序列分析和系统发育树构建对优势藻株种属进行鉴定,并比较了其对G418、氨苄青霉素和潮霉素的敏感性。结果表明,藻株X-1在奶牛养殖废水沼液中的适应能力最强,对沼液中总氮、总磷和COD的去除能力最强;藻株X-1与Chlorella sp.的相似度最高;小球藻X-1对G418的敏感性最强,G418可作为小球藻X-1基因工程中的选择标记抗生素,最佳浓度为160μg·mL~(-1)。该研究为小球藻X-1利用G418作为选择标记构建表达载体、转化小球藻、培养无菌藻系提供了实验依据。     

重离子突变藻株筛选及沼液处理性能研究

为了提高微藻在高浓度氮磷污水中的处理性能,利用重离子束辐照诱变普通小球藻CK-1#,选育得到突变藻株HM-3#。结果表明,HM-3#在模拟污水中生长良好,污染物去除效果相比初始藻株CK-1#提高明显。进一步考察HM-3#对猪场稀释沼液的处理性能,处理时间缩短1倍,生物量、光合色素和油脂含量可达到模拟污水中的1.50、1.57和2.19倍;NH₄⁺-N、TP和COD去除速率保持稳定,甚至优于在模拟污水中的结果,其值分别为22.44、2.43、47.84mg/（L·d）。综上,本研究通过重离子束辐照诱变筛选到一株适用于高浓度氮磷污水处理的优良突变藻株HM-3#,并于稀释沼液中验证该藻株具有良好的生长速率与高效的氮磷去除性能,为实现污水资源化利用提供了新的解决思路。     

沼液光催化处理研究

将光催化技术应用于沼液处理,是一种解决环境污染和最大化利用资源的新思路。在预处理之后的沼液中,加入Ti O2进行光催化反应,沼液的化学需氧量(COD)降低,可以降解沼液中难以生物降解的腐殖酸等有机物。光催化处理后的沼液颜色几乎透明,可做为光解水制氢的水源,产生的氢气又可作为制甲烷的氢源,进而实现生物甲烷制取过程中甲烷的高效转化。光催化处理沼液相比于其他的沼液处理方法具有成本低、效率高等优点,环境友好的同时还实现了资源的重复利用。     

小球藻处理污泥提取液的试验研究

首先采用加热煮沸、超声波、厌氧发酵等不同的方法对污泥进行了预处理,其中超声波破碎处理污泥的效果较好。再利用小球藻处理预处理后的污泥提取液,结果表明,小球藻对提取液中COD、TN、TP均有较高的去除率,最大去除率分别为97.4%,92.8%,73.9%。     

猪场沼液处理的应用研究

采用生物接触氧化(BCO)—序批式膜生物反应器(SBBR)—人工湿地(CW)工艺处理猪场沼液,处理规模150 m3/d,总投资101.45万元,运行费2.11元/(m3·d)。运行结果表明,该工艺处理后COD、BOD5、SS、NH3-N、TP去除率分别为91.7%、94.5%、93.2%、92.6%、86.2%,出水各项指标满足GB 18596—2001《畜禽养殖业污染物排放标准》要求。     

Removal of congo red from aqueous solutions by biogas waste slurry

Removal of Congo Red was carried out using biogas waste slurry as adsorbent at different concentrations of dye, adsorbent dosage, agitation time and pH. The process follows the first-order rate expression. The equilibrium data fit well in the Freundlich model of adsorption. Maximum removal of dye, 95%, was observed in the pH range 2.3–9.4. Desorption of Congo Red showed that it is solubilised in 50% acetic acid to the extent of 6% and the remainder appears to be chemically complexed irreversibly to the adsorbent. Low desorption of dye from the adsorbent surface in water indicates that the process may not be, essentially, a reversible one.     

污水处理中小球藻的自絮凝特性

以BG11(+N)培养基和模拟生活污水为底物,考察了污水处理小球藻(Chlorella vulgaris)的自絮凝特性,探究了自絮凝机理。结果表明:以短沉淀时间运行,小球藻在模拟生活污水中自然形成絮体,沉降性良好;藻细胞表面粗糙,含有丝状、胶状胞外聚合物;絮体内部含有大量短杆菌、球菌;絮体具有相对较高的Na、P、Fe、Ca、Mg元素含量,无机物中主要物质形态为Ca4O(PO4)2。污水处理小球藻的絮凝机理为:基质条件及反应器运行参数等促使藻细胞生理过程发生改变,藻细胞分泌更多絮凝性胞外聚合物增强黏附,生化过程富集P、Fe、Ca、Mg元素改善沉降性,絮凝性细菌大量繁殖促进菌藻共絮凝。     

高效氯氟氰菊酯对普通小球藻的毒性

[目的]通过高效氯氟氰菊酯在不同质量浓度下光合色素及SOD等生物量变化试验,了解高效氯氟氰菊酯对普通小球藻的毒性效应,为评价该药剂对水生生物的影响提供一定的理论依据。[结果]试验结果表明:高效氯氰菊酯对普通小球藻的抑制中浓度为105.71 mg/L,普通小球藻体内光合色素含量及SOD活力的随药剂质量浓度的变化均发生了变化。[结论]随着药剂处理质量浓度的增加,普通小球藻光合色素含量逐渐减少,SOD活力也随着药剂质量浓度的增加而急剧下降,且药剂对普通小球藻的毒性属于低毒。     

A/O—SBBR—氧化塘—人工湿地处理猪场沼液

针对猪场沼液氮磷浓度高、有机物含量大且可生化性差等特点,采用A/O—序批式生物膜反应器—氧化塘—人工湿地组合工艺对沼液进行深度处理。处理规模400 m~3/d,工程总投资117.5万,运行费用1.46元/(m~3·d)。运行结果表明,经过该组合工艺处理后COD_(Cr)、BOD_5、SS、NH_3-N、TP去除率分别为85.93%、79.84%、89.86%、94.78%、88.67%,出水指标均符合《畜禽养殖业污染物排放标准》(GB 18596—2001)要求。     

同步厌氧氨氧化甲烷化反硝化处理猪场沼液

针对猪场沼液脱氮难的问题,通过在UASB中实现同步厌氧氨氧化甲烷化反硝化达到脱氮除碳的目的.结果表明:中温条件下(31～35℃),UASB经过成功启动和90d的运行,逐步实现了同步厌氧氨氧化甲烷化反硝化,COD去除率为80% ～90%,NO2-N去除率为90%以上,总氮去除率为50% ～60%,氨氮去除率为8% ～24...     

Fenton-混凝法处理生活垃圾沼液试验研究

以内蒙古某生活垃圾处理厂厌氧发酵后的沼液为研究对象,研究了联合采用Fenton法和混凝法处理该沼液时提高沼液CODCr去除率及其可生化性的影响因素。通过试验分析得出:Fenton阶段,pH值为3,Fe2+的质量浓度为275 mg/L,m(H2O2)/m(Fe2+)为12,反应时间为3 h;混凝阶段,搅拌时间为20 min,pH值为8,聚合氯化铝(PAC)的投加量为10 mg/L,静置1 h。此条件下,CODCr、色度和浊度的去除率分别为69.7%、90.3%、83.3%,m(BOD5)/m(CODCr)约为0.23,可生化性得到提高。     

Supercritical CO2 extraction of pigment components with pharmaceutical importance from Chlorella vulgaris

BACKGROUND: Chlorella vulgaris is a green microalgae that contains various pigment components of carotenoids and chlorophylls. Supercritical CO₂ is widely used for extraction of pharmaceutical compounds because it is non‐oxic and easily separated from extracted material by simply depressurizing. In this work, pharmaceutical compounds from Chlorella vulgaris have been extracted using supercritical CO₂ with or without entrainer at various extraction conditions. RESULTS: Based on high performance liquid chromatography (HPLC) analysis, the extracts contained pigment components, such as lutein, β‐carotene, chlorophyll a and b. Higher extraction pressure and temperature promoted higher lutein extraction by supercritical CO₂. The optimum pressure and temperature for extraction were obtained as 50 MPa and 80 °C. Ethanol as an entrainer was more effective than acetone for the extraction of pigment components. Pigment components in the extract obtained by supercritical CO₂ with and without entrainer were compared with the extract obtained by a conventional extraction method. CONCLUSION: Supercritical CO₂ has been successfully applied for the extraction of pigment components from Chlorella vulgaris. Supercritical CO₂ enabled high selectivity for lutein extraction; however, the lutein yield was lower than that obtained by extraction using supercritical CO₂ with ethanol and soxhlet. Copyright © 2008 Society of Chemical Industry     

Antioxidant and Antibacterial Activity of Nutraceutical Compounds from Chlorella vulgaris Extracted in Hydrothermal Condition

Abstract

Water in hydrothermal condition has been used for extraction of nutraceutical compounds from Chlorella vulgaris. Hydrothermal extraction was carried out in a semi-batch and a batch extractor at various temperatures (120–200°C), pressures (2–10 MPa), and extraction times (30–300 min) to extract antioxidant and antibacterial compounds. The effect of extraction condition on the yield of extract was investigated. The antioxidant and antibacterial activity of extracts obtained by hydrothermal extraction were examined. The increasing extraction temperature resulted in higher antioxidant activity, but lower antimicrobial activity. As comparison with hot water extraction, the antioxidant activity of extract obtained by hydrothermal extraction was higher than that obtained by hot water extraction, but the antibacterial activity of the extract obtained by hydrothermal extraction was lower.     

Modified Photobioreactor for Biofixation of Carbon Dioxide by Chlorella vulgaris at Different Light Intensities

The performance of a modified bioreactor inside a light enclosure for carbon dioxide biofixation by Chlorella vulgaris was investigated. The influence of different light intensities on the CO₂ biofixation and biomass production rates was evaluated. The results showed that the photon flux available to the microalgal cultures can be a key issue in optimizing the microalgae photobioreactor performance, particularly at high cell concentrations. Although the optimal pH values for C. vulgaris are in the range of 6–8, cell growth can take place even at pH 4 and 10. Batch microalgae cultivation in the photobioreactor was used to investigate the effect of different light intensities. The maximum biomass concentration of 1.83 g L^?1 was obtained at a light intensity of 100 μmol m^?2s^?1 and under aeration with 2 L min^?1 of 2 % CO₂‐enriched air.