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961.
伊利金川污水处理厂的设计与运行 总被引:2,自引:0,他引:2
根据乳品生产中产生的污水水质特点,对伊利金川污水处理厂采用“调节-隔油-UASB-SBR”工艺进行了工程设计。运行结果表明,采用UASB工艺处理乳品生产中的污水,绝大部分有机物可由厌氧微生物进行降解及去除,每天可减少供氧能耗约7900kW·h,每年可节约电费约130万元。出水水质符合GB8978-1996《污水综合排放标准》中的一级标准。同时,污水处理厂每天可产生约14300m3沼气(含9875m3甲烷),相当于9.8吨标准煤。沼气可用于低压锅炉燃烧原料,对于缓解目前能源日益紧缺的压力和发展企业的循环经济具有非常重要的意义。该工艺还具有路线短及能源回收等优点,实用性强。 相似文献
962.
有机污染物的微生物处理研究进展 总被引:4,自引:0,他引:4
微生物处理是一种费用低,效果好,无二次污染且操作简单的处理方法。本文就国内外污泥中有机污染物的微生物处理进行了论述,总结了微生物处理有机污染的研究进展及其主要研究方向。 相似文献
963.
Production of polyethylene teraphtalate (PET) fiber in the world is increasing every year and reached to an amount of about 20 million tons a year in 2001. The wastes occur in the production of PET fiber in the amount of about 3–5% of total production. The PET does not degrade for a long time in nature. Since PET is a derivative of petroleum, the wastes of PET are valuable and must be recycled. One of the recycling method of PET wastes is re-melting. Thus, various properties of the PET wastes were improved using the re-melting method by employing an extruder manufactured for the work. Degradation during re-melting decreases the properties of the final product. The results indicate that the properties of recycled PET wastes can be monitored by designing the parameters of the extruder. Also, the further degradation of the material can be prevented and the recycling costs are minimized. 相似文献
964.
湘南红壤丘陵区农户经济行为对土地退化的影响分析——以祁东县紫云村为例 总被引:11,自引:0,他引:11
通过在湖南省祁东县紫云材进行的土地利用及农户经济行为调查,从土地状况、从业选择、农具、农田设施、耕作方式和效益等方面,分析了湘南红壤丘陵区农户社会经济行为对土地质量的影响。结果表明:紫云村农户重“品种”轻“土壤”,水田土壤有机质含量减少,理化性状变差,土壤自然肥力降低,旱地、林地粗放经营,质量退化。改变农户只重“品种”而忽视“土壤”的观念、提高耕地复种指数、建立合理的轮作体系和水土保持型高效集约持续的耕作制度、加强林业管理和经营、加大农业投入、搞好农田水利建设是防止本区土地退化和保证本区农业可持续发展的对策。 相似文献
965.
Roland Geyer Hans H. Richnow Dietmar Schlosser 《Water, Air, & Soil Pollution: Focus》2002,2(3):153-159
In experiments employing the lignocellulose-decaying basidiomycetes Trametes versicolor and Stropharia rugosoannulata degrading uniformly14C-labelled 2,4-dichlorophenol and pentachlorophenol, acombination of size exclusion chromatography (SEC),fractionation, and -scintillation counting wasapplied to quantify polymerisation products formed duringchlorophenol degradation. Time-dependent mass balances weregenerated by analysis of 14C in polymerisation products,CO2, as well as monomer non-polar and polar metabolites.Approximately 30% of the chlorophenols were found to bepolymerised. A major fraction of the polymerised productscorresponded to a molecular weight range from 0.24 – 40 kDa.Only a minor fraction could be attributed to a molecularweight >40 kDa. This method proved to be useful inquantification of polymerisation products and kinetics of thepolymerisation processes, whereas UV/Vis detection ofpolymerisation products separated by SEC led to false positiveresults. The SEC-14C method could also be applied forother complex processes where polymerisation ordepolymerisation occurs (humification, degradation oflignocellulose, formation of bound residues from xenobioticssuch as polycyclic aromatic hydrocarbons or 2,4,6-trinitrotoluene) and where spectrophotometric determinationsare difficult or impossible. 相似文献
966.
Thapa GB 《Environmental management》2001,27(5):667-679
Mountain watersheds, comprising a substantial proportion of national territories of countries in mainland South and Southeast
Asia, are biophysical and socioeconomic entities, regulating the hydrological cycle, sequestrating carbon dioxide, and providing
natural resources for the benefit of people living in and outside the watersheds. A review of the literature reveals that
watersheds are undergoing degradation at varying rates caused by a myriad of factors ranging from national policies to farmers'
socioeconomic conditions. Many agencies—governmental and private—have tried to address the problem in selected watersheds.
Against the backdrop of the many causes of degradation, this study examines the evolving approaches to watershed management
and development. Until the early 1990s, watershed management planning and implementation followed a highly centralized approach
focused on heavily subsidized structural measures of soil conservation, planned and implemented without any consultation with
the mainstream development agencies and local people. Watershed management was either the sole responsibility of specially
created line agencies or a project authority established by external donors. As a consequence, the initiatives could not be
continued or contribute to effective conservation of watersheds. Cognizant of this, emphasis has been laid on integrated,
participatory approaches since the early 1990s. Based on an evaluation of experiences in mainland South and Southeast Asia,
this study finds not much change in the way that management plans are being prepared and executed. The emergence of a multitude
of independent watershed management agencies, with their own organizational structures and objectives and planning and implementation
systems has resulted in watershed management endeavors that have been in complete disarray. Consistent with the principle
of sustainable development, a real integrated, participatory approach requires area-specific conservation programs that are
well incorporated into integrated socioeconomic development plans prepared and implemented by local line agencies in cooperation
with nongovernment organizations (NGOs) and concerned people. 相似文献
967.
968.
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970.
The biodegradability of the edible films made of whey proteins by disulfide cross-linking was investigated. Whey protein concentrate (WPC) and whey protein isolate (WPI) films were subjected to microbial degradation using Pseudomonas aeruginosa and composting burial degradation. Results from the microbial degradation showed that whey protein films could support the growth of P. aeruginosa. The bacterial growth characteristics were well described using the Gompertz model. WPC films degraded faster than WPI films, suggesting that the biodegradability of protein films is associated with the film composition and the extent of covalent cross-linking. WPI films buried in a compost pile began to degrade in two days and became darker over time. More than 80% of total solids were lost in 7 days. 相似文献