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41.
Biodiesel produced by transesterification of waste animal oil is a promising green fuel in the future. ZnO-Al2O3 and ZnO/Zn2Al composition oxides were prepared by co-precipitation method and impregnation method, respectively. The above catalysts were characterized by X-ray diffraction (XRD), Brunauer--Emmett--Teller (BET) and CO2 adsorption and temperature-programmed desorption (CO2-TPD) and show that the high activity for the catalyst is attributed to its high alkalinity. The reaction parameters were optimized and the results show that the transesterification ratio of waste animal oil can reach 98.7% with 10% ZnO/Zn2Al catalyst after 2 h. Moreover, 10%ZnO/Zn2Al compound oxides can be active for the successive cycles. The glycerol as a predominant by-product after transesterification is of high purity with high use value. 相似文献
42.
Bioconversion of dairy manure by black soldier fly (Diptera: Stratiomyidae) for biodiesel and sugar production 总被引:1,自引:0,他引:1
Modern dairies cause the accumulation of considerable quantity of dairy manure which is a potential hazard to the environment. Dairy manure can also act as a principal larval resource for many insects such as the black soldier fly, Hermetia illucens. The black soldier fly larvae (BSFL) are considered as a new biotechnology to convert dairy manure into biodiesel and sugar. BSFL are a common colonizer of large variety of decomposing organic material in temperate and tropical areas. Adults do not need to be fed, except to take water, and acquired enough nutrition during larval development for reproduction. Dairy manure treated by BSFL is an economical way in animal facilities. Grease could be extracted from BSFL by petroleum ether, and then be treated with a two-step method to produce biodiesel. The digested dairy manure was hydrolyzed into sugar. In this study, approximately 1248.6 g fresh dairy manure was converted into 273.4 g dry residue by 1200 BSFL in 21 days. Approximately 15.8 g of biodiesel was gained from 70.8 g dry BSFL, and 96.2 g sugar was obtained from the digested dairy manure. The residual dry BSFL after grease extraction can be used as protein feedstuff. 相似文献
43.
不同培养条件下锰过氧化物酶(MnP)的合成及其对甲基橙的降解 总被引:1,自引:0,他引:1
高效、大规模、低成本合成木质素降解酶是直接采用其降解难降解有机污染物所必须解决的问题.对锰过氧化物酶(MnP)降解甲基橙和在非灭菌的反应器中连续合成MnP的可行性进行考察.结果表明,在采用2 mmol H2O2和1.5 mmol MnSO4的降解体系中,获最大脱色效果,且100、200和300 U/L的MnP可在8h内将甲基橙分别脱色18%、23%和35%;在非灭菌的反应器水平上实现了固定化培养的P.chrysosporium连续23 d合成MnP,但MnP酶活仅为2~ 23 U/L,难以酶解甲基橙;然而,在摇瓶培养条件下固定化的P.chrysosporium合成的MnP却能达1 152 U/L.因此,直接采用MnP对污染物进行降解以及在非灭菌的反应器中持续合成MnP是可行的,但就在非灭菌条件下如何提高MnP的合成量还有待开展深入的研究. 相似文献
44.
郝志强 《安全.健康和环境》2017,17(6)
从消防安全基本原理出发,分析了油田企业消防力量配置上的两大误导因素,论述了油田企业消防力量配置的基本构想,提出了5种典型场站消防力量配备原则。 相似文献
45.
随着车辆技术进步和燃油品质提升,河南省在用柴油车加载减速污染物现行排放限值已不能对高排放车辆进行有效监控。依据《确定压燃式发动机在用汽车加载减速法排气烟度排放限值的原则和方法》(HJ/T 241—2005),采用相对光吸收系数与累积频率法,对9 458份在用柴油车检测数据进行统计分析,提出符合河南省的在用柴油车排放限值。建议河南省在用国三、国四、国五轻型柴油车尾气光吸收系数限值分别为0.98、0.89、0.76m~(-1),而相应重型柴油车尾气光吸收系数限值分别为0.66、0.62、0.48m~(-1);依据该限值,河南省在用柴油车的年检合格率控制在82.6%,高排放柴油车比例为17.4%,符合HJ/T 241—2005的要求。 相似文献
46.
采用联合式催化剂新技术,在低温下进行了一氧化碳和氢化同消除的试验,通过实验考察取得了良好的效果。 相似文献
47.
负载型金催化剂用于室温下CO的消除 总被引:4,自引:0,他引:4
从催化活性、抗潮湿、抗硫中毒、稳定性等方面考察了负载型金催化剂对于CO氧化反应的性能。筛选出的2-3催化剂可在-22℃下完全消除CO,并且在催化活性、抗潮湿、抗硫中毒、稳定性等方面具有现行催化剂无法比拟的优点。 相似文献
48.
Partitioning and removal of dioxin-like congeners in flue gases treated with activated carbon adsorption 总被引:4,自引:0,他引:4
Activated carbon adsorption is commonly used to control dioxin-like congener (PCDD/Fs and PCBs) emissions. Partitioning of PCDD/Fs and PCBs between vapor and solid phases and their removal efficiencies achieved with existing air pollution control devices (APCDs) at a large-scale municipal waste incinerator (MWI) and an industrial waste incinerator (IWI) are evaluated via intensive stack sampling and analysis. Those two facilities investigated are equipped with activated carbon injection (ACI) with bag filter (BF) and fixed activated carbon bed (FACB) as major PCDD/F control devices, respectively. Average PCDD/F and PCB concentrations of stack gas with ACI+BF as APCDs are 0.031 and 0.006ng-TEQ/Nm(3), and that achieved with FACB are 1.74 and 0.19ng-TEQ/Nm(3) in MWI and IWI, respectively. The results show that FACB could reduce vapor-phase PCDD/Fs and PCBs concentrations in flue gas, while the ACI+BF can effectively adsorb the vapor-phase dioxin-like congener and collect the solid-phase PCDD/Fs and PCBs in the meantime. Additionally, the results of the pilot-scale adsorption system (PAS) experimentation indicate that each gram activated carbon adsorbs 105-115ng-PCDD/Fs and each surface area (m(2)) of activated carbon adsorbs 10-25ng-PCDD/Fs. Based on the results of PAS experimentation, this study confirms that the surface area of mesopore+macropore (20-200A) of the activated carbon is a critical factor affecting PCDD/F adsorption capacity. 相似文献
49.
50.
Pan G Zhang MM Chen H Zou H Yan H 《Environmental pollution (Barking, Essex : 1987)》2006,141(2):195-200
Algal removal abilities of 26 clays/minerals were classified into three categories according to the 8-h equilibrium removal efficiency (Q8h) and removal rate at a clay loading of 0.7 g/L. Type I clays (sepiolite, talc, ferric oxide, and kaolinite) had a Q8h > 90%, a t50 (time needed to remove 50% of the algae) < 15 min, and a t80 < 2.5 h. Type II clays (6 clays) had a Q8h 50-90%, a t50 < 2.5 h, and a t80 > 2.5 h. Type III clays (14 clays) with Q8h < 50%, t50 > 8 h and t80 > 14 h had no practical value in removal of algal blooms. When the clay loading was reduced to 0.2 g/L, Q8h for all the 25 materials decreased to below 60%, except for sepiolite whose Q8h remained about 97%. The high efficiency for sepiolite to flocculate M. aeruginosa cells in freshwaters was due to the mechanism of netting and bridging effect. 相似文献