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961.
This article begins by summarizing the importance of the forestry sector in the Philippine economy It provides an overview of the multiplicity of Philippine governmental institutions involved in forestry in 1982 Then it discusses forestry laws in the country and concludes by examining fifteen critical forest policy issues: sustained yield management; area-specific logging bans; increased use of wood wastes; revision of forest charges; unprocessed log export ban; rationalization of the forest industry, acceleration of reforestation; protection of watersheds; recognition of the social dimensions of slash- and-burn agriculture; fuelwood supply; public land classification for forestry and agriculture, development of plantations for dendrothermal electricity; multiple-use management; preservation of mangrove areas, and improvements in administration and implementation.Research for this paper was supported by the East-West Center Environment and Policy Institute. The author would like to acknowledge the assistance of the Natural Resources Management Center of the Philippine Ministry of Natural Resources. 相似文献
962.
本文介绍了四川原煤及其废渣与制品的γ辐射剂量率、附加γ辐射人均年有效剂量量。同时,用低本底Ge(Li)多道γ能谱仪测定了原煤、矸粉与矸砖,煤渣与煤渣砖、粉煤灰及粘土砖等样品中的天然放射性核素~(238)U,~(232)Th,~(226)Ra,~(40)K的比活度。经比较和研究,找出了这些物质的放射性水平及它们彼此之间的规律。 相似文献
963.
Waste plastics recycling process using coke ovens 总被引:3,自引:0,他引:3
Kenji?KatoEmail author Seiji?Nomura Hiroshi?Uematsu 《Journal of Material Cycles and Waste Management》2003,5(2):98-101
The Japan Iron and Steel Federation (JISF), as its voluntary energy-saving action plan, proposed a 10% energy reduction by 2010 with 1990 as the basis. Further, it has suggested an additional 1.5% energy saving by the use of waste plastics as a metallurgical raw material. The amount of processing of waste plastics which corresponds to this amount of energy conversion is about 1 million t scale during 1 year. Conventional known methods for recycle-processing of waste plastics include, for example, the method of injection into a blast furnace to use waste plastics as an iron-ore reducing agent instead of coal. On the other hand, the coking process is considered to be suitable as a waste plastic recycling facility because the process involves coal carbonization in a high-temperature and reducing atmosphere. Carbonization tests with mixed waste plastics were conducted with laboratory equipment and in actual coke ovens. As a result, it was confirmed that the waste plastics recycling process using coke ovens is feasible. Therefore, a waste plastics recycling process using coke ovens was started as a chemical recycling technology at Nippon Steel. 相似文献
964.
Hans-Joachim Uth 《Environmental management》1989,13(3):317-323
Spectacular industrial accidents, such as the ones in Bhopal, Mexico City, and Basle, have in recent times made the risks associated with the modern chemicals industry unmistakably evident. It has been seen that effective emergency plans for the people living in the vicinity of a hazardous installation become particularly important. The situation of hazardous installations in the Federal Republic of Germany is reviewed and the three-stage safety system, which is established within the German Regulation on Major Industrial Accidents (Störfallverordnung), is described. The evaluation of the current practice shows a couple of problems, especially connected with off-site safety precautions. The disaster control teams are often ill-equipped and inadequately trained. There is a need for further establishment of detailed and specific emergency plans, especially in rural areas. It is expected that the updating of the Regulation on Major Industrial Accidents, which is at present being undertaken in the Federal Republic of Germany and the compilation of instructions for the competent authorities will contribute to better emergency plans for the protection of areas in the vicinity of hazardous industrial installations. 相似文献
965.
966.
煤炭工业作为内蒙古的传统产业,在工业经济中占有举足轻重的地位。近年来,随着自治区"大煤田、大煤电、大煤化"战略的实施,煤炭工业正发挥着支柱产业的作用,推动自治区经济大步前进,煤炭经济取得了长足的发展,但也仍然存在开发工艺落后,能源与环境代价高,增长方式粗放和利益分配严重失衡导致的发展混乱等一系列问题。因而需要对煤炭经济的发展进行战略规划。 相似文献
967.
Citrate (Ct) was chosen as a typical chelator used in the Fe2+-peroxydisulfate (PDS) process to improve sludge dewaterability.The PDS-Fe2+-Ct process exhibited better performance in sludge dewatering than PDS-Fe2+.Specifically,with a PDS dosage of 1.2 mmol/g VS,the molar ratio of PDS/Fe2+and Ct/Fe2+were 4:5 and 1:4,respectively,the capillary suction time decreased from 155.8 to 24.8sec,and the sludge cake water content decreased from 82.62%t... 相似文献
968.
在氯碱工业加工过程中会产生大量的甲烷氯化物废水,废水中含有大量的甲烷氯化物,该类废水不易处理,极大地影响了后续废水处理工作的开展。本文以某司甲烷氯化物具体试验为例,探讨高分子吸附剂在甲烷氯化物废水处理过程中的应用,在利用高分子吸附剂进行吸附的同时通过蒸汽吹脱使树脂中富集下来的甲烷氯化物得到分离回收,从而实现了废水的资源化,达到治废与资源利用的双重效果。 相似文献
969.
煤矸石和粉煤灰pH与电导率动态变化规律及其相关性研究 总被引:8,自引:0,他引:8
煤矸石和粉煤灰是煤矿区两种常见的固体废弃物,对环境造成极大的污染。pH波动幅度大是废弃物农用治理的主要障碍之一。对两种废弃物连续浸提时的pH和电导率(EC)进行长期动态监测,结果表明,不同层次的煤矸石尽管风化程度不同,但经过长时间浸取后,pH和EC变化趋势相似,且煤矸石、粉煤灰的pH、EC值有很大的相关性。该试验为今后两种废弃物合理利用奠定了基础。 相似文献
970.
Frank M. Hauser Tim Metzner Thorsten Rößler Michael Pütz Steffen Krause 《Environmental Forensics》2019,20(1):13-25
The entry of illegally discharged waste into the sewage system can cause serious damage to sewage pipes and harm the public domain. Besides industrial and communal sources, discharges from clandestine laboratories are of special forensic interest. Aim of this study is to investigate the possibility to detect clandestine discharges of possibly hazardous waste directly at the point of discharge. Tests were performed at a facility where real wastewater was pumped in a controlled way through an open sewage pipe above ground. Chloride, ammonia, pH and conductivity electrodes were investigated for their ability to detect discharges of different types of waste. Waste samples were diluted up to 50 times in a static wastewater environment and pH, conductivity and chloride electrodes were able to distinguish all waste dilutions from blank wastewater. These three electrodes were then used for dynamic tests by placing them inside flowing sewage water and discharging different types of liquid waste ten meters upstream of them. Parameters of the waste discharges like volume, time interval and speed of discharge were varied and the responses of the electrodes were collected. The dynamic tests showed that these three electrodes were able to pick up different waste discharges in a real wastewater environment. It was found that a high sampling rate of the sensors would be required to connect a certain discharge to a specific household connection. These findings highlight the possibility to locate illegal discharges, coming from a variety of sources, using the waste discharge itself. 相似文献