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791.
Utilization of ash residues, including coal ash, oil ash, and municipal solid waste combustion ash, for the construction of artificial reefs at sea has been investigated by many researchers throughout the world for nearly 20 years. Both laboratory and field studies have shown that an artificial reef made of stabillized ash-concrete (SAC) has had no adverse effect on the marine environment. Indeed, published studies have shown that fish counts increase around SAC reefs owing to an abundance of colonizing organisms and to protection provided by cavities within the reef structures. However, public and regulatory resistance to the use of SAC for artificial reef construction at sea is still very strong in certain countries due to concern for possible negative environmental impacts, primarily in the area of bioaccumulation of elements or compounds originating from the ash component of SAC.
In this paper, technological feasibility of using ash residues for artificial reef construction is presented, based on the available 20 years of scientific data, including engineering workability, physical integrity, chemical leaching potential and biological effects. More important, we also identify conceptual barriers for the acceptance of using SAC for the construction of ocean reefs and suggest approaches to overcome these barriers. 相似文献
In this paper, technological feasibility of using ash residues for artificial reef construction is presented, based on the available 20 years of scientific data, including engineering workability, physical integrity, chemical leaching potential and biological effects. More important, we also identify conceptual barriers for the acceptance of using SAC for the construction of ocean reefs and suggest approaches to overcome these barriers. 相似文献
792.
David M. Bjerklie Jacqueline D. LaPerriere 《Journal of the American Water Resources Association》1985,21(2):235-242
Effects of placer mining on the hydrology and water quality of several interior Alaska streams were studied as part of a project on the impacts of placer mining on stream ecosystems. Surface and subsurface waters were analyzed in the field for conductivity, pH, temperature, alkalinity, total and calcium hardnesses, iron, copper, manganese, ammonia-N, nitrate-N, nitrite-N, settleable solids, and turbidity. Total, nonfiltrable, and filtrable residues were determined in the laboratory. In the streams placer mining increased turbidity, settleable solids, nonfiltrable and filtrable residues and total iron. Surface and subsurface water levels, as measured in wells driven in the stream beds, were correlated with stream flow. Fine sediment deposited on stream beds in mined drainages reduced the hydraulic contact between the surface and subsurface waters of the stream and caused the piezometric water level to be below the surface water level of the mined streams. This resulted in higher specific conductance and significantly lower dissolved oxygen concentrations in the subsurface waters of mined streams compared to their surface waters. No significant differences were found for any water quality characteristics comparing surface to subsurface waters for the unmined streams. 相似文献
793.
针对江苏省常州市地区村镇自建住宅的抗震性能进行了调查研究,针对存在的问题提出了相应的抗震设防措施与对策. 相似文献
794.
牡丹江市水源地水栉霉污染事件成因分析及对策研究 总被引:1,自引:0,他引:1
通过现场调查和实验室测试,对牡丹江水源地污染事件进行了全面的研究,分析水栉霉的形成的原因.得出海林雪原酒业公司向海浪河大量排放酒糟是产生该事件的主要因素这一结论,并提出预防因这种水生生物而引起的水污染的建议和措施. 相似文献
795.
巴县1993年乡镇工业污染损失大约为2.29亿元,约占当年全县GNP的7.8%。其中农业损失约占45%,人体健康损失约占28%。受酸雨作用的钢材和建筑物的损失为0.26亿元,相当于全县当年新增的生产性固定资产的大部分。文章还论述了巴县乡镇工业污染损失贡献权重系数的参数取值过程。 相似文献
796.
797.
利用造纸黑液制水煤浆添加剂新技术 总被引:1,自引:0,他引:1
生产水煤浆所需的添加剂,因价格居高不下而影响这种煤基液体燃料的发展。利用碱法造纸黑液和经改造的造纸生产设备,将浓缩黑液稍加酸化、磺化处理后在一定压力、温度下反应,可制成性能良好的添加剂,利用该添加剂生产1吨水煤浆只增加约10元成本。 相似文献
798.
MonitoringofPotentialcarcinogenicpolycyclicaromaticcompoundsintheemissionfromcoalcombustionCuiWenxuan,YaoWeixi,XuXiaobai(Rese... 相似文献
799.
800.
以地理信息系统,全球定位系统,遥感为主体和核心的地理信息学在煤矿环境管理中有着广泛的应用。本文在对地理信息学及其应用于煤矿环境管理的优点进行简要介绍和分析的基础上,对其在煤矿环境信息采集,监测,评价,治理等方面的应用进行了系统的探讨。 相似文献