Chlorpyrifos degradation in a biomixture of biobed at different maturity stages

The biomixture is a principal element controlling the degradation efficacy of the biobed. The maturity of the biomixture used in the biobed affects its overall performance of the biobed, but this is not well studied yet. The aim of this research was to evaluate the effect of using a typical composition of Swedish biomixture at different maturity stages on the degradation of chlorpyrifos. Tests were made using biomixture at three maturity stages: 0 d (BC0), 15 d (BC15) and 30 d (BC30); chlorpyrifos was added to the biobeds at final concentration of 200, 320 and 480 mg kg⁻¹. Chlorpyrifos degradation in the biomixture was monitored over time. Formation of TCP (3,5,6-trichloro-2-pyrinidol) was also quantified, and hydrolytic and phenoloxidase activities measured. The biomixture efficiently degraded chlorpyrifos (degradation efficiency >50%) in all the evaluated maturity stages. However, chlorpyrifos degradation decreased with increasing concentrations of the pesticide. TCP formation occurred in all biomixtures, but a major accumulation was observed in BC30. Significant differences were found in both phenoloxidase and hydrolytic activities in the three maturity stages of biomixture evaluated. Also, these two biological activities were affected by the increase in pesticide concentration. In conclusion, our results demonstrated that chlorpyrifos can be degraded efficiently in all the evaluated maturity stages.     

Deterioration of bioplastic carrier bags in the environment and assessment of a new recycling alternative

Increasing environmental concerns and the introduction of technologies based on renewable resources have stimulated the replacement of persistent petroleum-derived plastics with biodegradable plastics from biopolymers. As a consequence, a variety of products are currently manufactured from bioplastic, including carrier bags. This series of studies investigated the deterioration of carrier bags made with Mater-Bi (MB), a starch-based bioplastic, in soil, compost and two aquatic ecosystems, a littoral marsh and seawater. Results from the laboratory study indicated that bioplastic carrier bags were rapidly deteriorated in soil and compost. After three months of incubation, weight loss of specimens was of 37% and 43% in soil and compost, respectively. Conversely, little deterioration was observed in specimens buried in soil under field conditions or exposed to water of a littoral marsh and of the Adriatic Sea. These findings were consistent with the greater number of bacteria and especially fungi capable of degrading MB that were recovered from soil and compost with respect to the two aquatic ecosystems. Considering that a variety of microbial isolates are capable of using MB as a source of carbon, a new alternative to recycle these MB-based carrier bags was explored. More specifically, starchy residues from bags were fermented by the fungus Rhizopus oryzae to produce up to 35 mg of lactic acid per g of bag residues.     

印染废水处理工艺改造的实践与探讨

根据某印染废水的特点 ,在原有传统处理工艺的基础上进行了工艺改造 ,将调节池改为水解酸化池 ,将活性污泥曝气池改为接触氧化池 ,在池内形成了合理的微生物分布 ,大大地改善了出水水质 ,使 COD、SS、硫化物、色度的去除率分别提高了 2 2 %、10 %、36 .4%、2 5 %。既满足废水排放标准 ,又节约了土建资金。     

磁化处理污水的生物效应试验

论文通过磁化处理污水的试验分析 ,研究了磁化对好氧微生物的活性、灭菌及促进藻类初级生产力等的生物效应 ,并进一步分析了磁化去除有机物的机理。     

生物脱氮除磷工艺好氧区硝化功能的强化试验

在活性污泥法脱氮除磷工艺系统的好氧段投放高硬度聚乙烯悬浮小球作为生物载体，可以强化系统的硝肥功能，提高处理系统的脱氮除磷效率，同时避免产生填料间污泥结团。经两套试验装置的５种工况条件下平行对照试验结果表明：好氧区全池投放聚乙烯悬浮小球，装填密度在１０％￣１５％，ＴＫＮ去除率达９８．２％，ＴＮ去除率达到８６％，ＴＰ去除率达到９１％。     

受污染饮用水水源生物预处理技术

阐述了以石英砂、陶粒和弹性立体为填料的生物滤池、生物流化床和生物接触氧化等几种常见受污染饮用水水源生物预处理技术的工艺特点，运动参数及处理效果，及国内以淮水为源水的蚌埠自来水厂、以姚江为源水的宁波梅林和和以深圳水库为源水的，３个日处理量分别为１万ｔ、４万ｔ和４００万ｔ的生物预处理工程情况，并对生物接触氧化法预处理工艺的填料选择、挂膜、气水比和积泥反冲等技术问题进行了讨论。     

甲烷生物燃料电池的产电影响因素及机制研究

考察了阳极电极材料、电极面积、电极电位、pH、阴极电子受体对甲烷生物燃料电池(MFC)产电性能的影响,并通过高通量测序、循环伏安法(CV)分析了其可能的电催化机制.结果 表明,透气布/碳布(GTC)复合材料为阳极时产电性能(1251.3 mA·m-2)最佳,分别是石墨烯/中空纤维膜(G-HFM)阳极(34.8 mA·m...     

生物炭对土壤酶活和细菌群落的影响及其作用机制

生物炭因其独特的理化性质能够提高土壤碳氮矿化速率及改善土壤微生态环境,因此探索生物炭调控土壤微生态环境与土壤酶活及其作用机制对改善土壤质量具有重要意义.采用大田试验方式研究不同生物炭施用水平0(CK2)、0.6(T1)、0.9(T2)、1.2(T3)和1.5(T4)t·hm-2以及完全空白对照(CK1:不施任何肥料和生...     

溶解氧对Anammox滤池内功能菌群及活性的影响

针对目前厌氧氨氧化系统内微生物的研究,主要以厌氧氨氧化菌本身这一情况,本研究对长期稳定运行的Anammox滤池内微生物菌群结构进行了测定,同时测试与分析了滤池内厌氧氨氧化菌(AnAOB)、氨氧化菌(AOB)、亚硝酸盐氧化细菌(NOB)和反硝化菌(DNB)的关键动力学常数,探究了溶解氧(DO)浓度从0.2mg/L增加至1...     

黑水虻对三种病原菌的杀灭作用研究

畜牧业的蓬勃发展带来了愈发严重的畜禽粪便病原菌污染问题,黑水虻作为一种重要的资源昆虫,其幼虫能有效杀灭畜禽粪便中的病原菌,并生产出有价值的附加产品.为探究黑水虻幼虫杀灭畜禽粪便中病原菌的具体规律和机制,开展了黑水虻幼虫杀灭大肠杆菌O157∶H7(Escherichia coli O157∶H7)、沙门氏菌(Salmon...