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251.
石油工业废弃物处置及其生物治理趋势 总被引:4,自引:0,他引:4
鉴于我国石油工作者对石油工业废弃物的普遍关注,现在介绍生物治理的基本概念及SPE石油工程师协会中有关含油污泥生物处置的途径及其突出优越性。生物液/固处理工艺(LST)是目前含油污泥处置现场最经济可行的处置方案。这种好氧的LST工艺过程,能够比较充分地代谢和降解石油污泥中的油和脂并大量除去多环芳烃类(PAH)化合物及其它有机化合物,明显地降低了石油废弃物对人、畜的毒害程度。其工艺较简单,操作也简易,凡经此工艺处理后的废弃物不留残毒和后患,因此早已被世界上先进国家的炼油业视为处理含油污泥的有效选择了。石油工业废弃物的生物防治和生物降解工艺较大程度地领先于目前我国现场正在执行的各种处理含油废弃物的处理工艺。 相似文献
252.
通过理论分析和大量实验工作,找出了现行国家标准的悬浮物测定方法在测定高含盐污水时的不足之处,并且提出了准确的测定方法。新方法不仅能很好地反映水样的实际状况,而且可以推广应用于各种复杂水样的悬浮物的测定。 相似文献
253.
Park design principles are proposed on the basis of consideration and analysis of rare plant species in Great Smoky Mountains National Park, USA. Rare species richness can be used as a simple measure of preservation success. A semilogartihmic species-area model for the Smokies was used in this analysis. Species richness would increase logarathmically with expansion of the national park area. An analysis of the relationship between species richness and the distribution of geologic and topographic features in the national park was also reported. An asymptotic relation was documented for the accumulation of newly recorded rare and endangered vascular plant species in the Smokies region up to 1978. Several multiple regression linear models predicted rare vascular plant species richness in Great Smoky Mountains National Park from area and topographic variates.Preserve design criteria can be based upon species-area, environmental gradient, and natural features distribution patterns for the specific taxa and biogeographic region under consideration. In addition, natural history characteristics for particular vulnerable species must be assessed. Rather than concentrating on the preservation of undocumented immigration and extinction processes, preserve design should be directed towards protecting geographic components and gradient patterns characteristic of a region. 相似文献
254.
Hugh Lehman 《Journal of Agricultural and Environmental Ethics》1988,1(2):155-162
According to a rights view it is acceptable to kill animals if they are innocent threats or shields or are in a lifeboat situation. However, according to advocates of such a view, our practices of killing animals for food or scientific research may be morally unacceptable. In this paper we argue that, even if we grant the basic assumptions of a rights view, a good deal of killing of animals for food and scientific research continues to be morally acceptable. 相似文献
255.
Peter F. M. McLoughlin 《Journal of the American Water Resources Association》1988,24(3):599-607
ABSTRACT: Third World irrigation and drainage systems have experienced major declines recently in both capability and performance. This is due initially to working them well beyond their design capaci-capacities; scouring, sedimentation, and overtopping result. Chronic O&M underfunding then adds heavily to this worsening malaise. International donors have assisted irrigation departments with rehabilitation projects and programs to improve O&M effectiveness on a grand (billions of dollars) scale. Despite their historical propensity to examine, almost fastidiously, program economic justifications (B/C, IRR, etc), the donors apparently have glossed over two basic analytic elements for (a) more spending on O&M as distinct from an equivalent spending on other means to provide farmers with an m3 of water; and (b) different levels of O&M spending on canals and drains. Surely those different levels provide differing benefits, in total, and at the margin. Which level is most economic? This paper identifies these latter analytical issues, posits methodologies key to an O&M spending level analysis, and discusses the information base. Particular attention is paid to identifying relevant costs and benefits, and to suggesting supplementary criteria for O&M spending level selection. The paper is an exercise in delineation of an imminently practical area of irrigation engineering economics. 相似文献
256.
257.
The National Forest Management Act (1976) specifies that multiresource inventories be conducted to provide baseline data for
development and, later, monitoring of national forest management plans. This mandate entails the most ambitious and complex
resource planning effort ever attempted. In this paper we evaluate the structure and use of current inventory-monitoring programs
and recommend a framework for gathering data to improve national forest planning. Current national guidelines are general
and provide only basic directions to forest-level planners. Forest inventories have traditionally concentrated on timber.
Although these inventories are often well designed, the questions we are now asking about forest resources have outgrown these
methods. Forest management is impeded by general confusion over definitions of resources and the interactions among them.
We outline a simple classification scheme that centers on identification of basic ecosystem elements that can be readily measured.
Furthermore, spatial and temporal scales must be considered in the design of inventory-monitoring programs. The concept of
ecological indicators is reviewed, and caution is advised in their use. Inventory-monitoring programs should be goal-directed
and based on as rigorous a statistical design as possible. We also review fundamental issues of variable selection, validation,
and sampling bias. We conclude by developing a flexible inventory-monitoring program that is designed to provide information
on individual characteristics of the environment, rather than being based on fixed definitions of resources. 相似文献
258.
259.
新疆八一钢铁有限责任公司炼铁厂上料系统1^#转运站,1^#a转运站,2^#转运站及1^#、2^#高炉高道料仓在上料时,粉尘污染较为严重,为解决粉尘污染问题,1999年炼铁厂组织设计与施工了40m^2单室卧式3电场除尘器,工程投运后,收尘效果良好,岗位粉尘浓度与外排浓度均低于国家标准。 相似文献
260.
城市生活垃圾综合处理前分选系统设计 总被引:2,自引:0,他引:2
本文以江油市城市生活垃圾处理厂为工程实例,介绍了垃圾前分选系统中的垃圾储料车间、行车与抓斗、垃圾上料机构、双层振动筛以及人工分选平台的工艺设计参数及设计依据,并在此基础上提出了该系统的改进建议. 相似文献