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71.
填埋场不同深度垃圾土压缩性的室内试验研究 总被引:2,自引:1,他引:1
阐述了垃圾土的压缩机理,归纳了国内外垃圾土压缩性指标的研究成果。根据某填埋场3个不同深度的垃圾土试样,在改装后的高压固结仪上进行压缩试验,得到垃圾土的压缩系数a、主压缩指数C、修正主压缩指数C'、压缩模量E以及体积压缩系数m,并对试验结果进行分析。试验结果表明,垃圾土的初始孔隙比随填埋深度的增加而减小,垃圾土的压缩指数随其可降解度和有机质含量的减少而降低,垃圾土具有高压缩性,其压缩性指标与垃圾的组成和填埋深度有关。将得到的压缩性指标与国内外的资料进行了比较,可为填埋场的设计及变形计算提供参考。 相似文献
72.
Rangesan Narayanan Dean T. Larson Trevor C. Hughes 《Journal of the American Water Resources Association》1985,21(3):407-416
During the 1976–77 drought, three principal mechanisms were used to reduce water use in Utah communities: price increases, maximum monthly use restrictions, and restrictions on outdoor watering times. A regression model was developed to explain observed changes in water use, with price, type of restriction, household size, and summer rainfall as independent variables. For an average system, a 1 percent increase in price would reduce water use by 0.07 to 0.09 percent. A 1 percent increase in outdoor watering time restriction reduces use by 0.064 to 0.075 percent. A 1 percent increase in quantity restrictions leads to a reduction in water use of 0.014 to 0.054 percent. The effectiveness of rationing policies is influenced by system characteristics. For example, outdoor watering time restrictions were less effective in systems with above average household size and below average monthly use. 相似文献
73.
Richard A. Herbert Darrell D. Carlson Gregg J. Wiche 《Journal of the American Water Resources Association》1985,21(6):953-965
The crest-stage gage program in Louisiana was evaluated to determine if the data were adequate for use in developing regional flood-frequency equations and to determine if any crest-stage gage stations could be discontinued. An abundance of data at many crest-stage gage stations and a lack of data for urban areas and flat-slope areas indicated a need for a shift in the number, type, and locations of gages. Correlations and comparisons of annual peak discharges and watershed characteristics of 96 existing stations resulted in the elimination of 72 stations and the addition of one new station, reducing the total network to 25 stations that could be used for future flood-frequency analyses. The adequacy of the reduced network for development and verification of regional flood-frequency equations was tested by comparing a set of regional flood-frequency equations developed using data from the full network with a set developed using data from the reduced network. The results indicate that the crest-stage gage network can be reduced to 25 stations and still provide adequate information for future flood-frequency analyses. 相似文献
74.
Sheryl L. Franklin David R. Maidment 《Journal of the American Water Resources Association》1986,22(4):611-621
ABSTRACT: A cascade model for forecasting municipal water use one week or one month ahead, conditioned on rainfall estimates, is presented and evaluated. The model comprises four components: long term trend, seasonal cycle, autocorrelation and correlation with rainfall. The increased forecast accuracy obtained by the addition of each component is evaluated. The City of Deerfield Beach, Florida, is used as the application example with the calibration period from 1976–1980 and the forecast period the drought year of 1981. Forecast accuracy is measured by the average absolute relative error (AARE, the average absolute value of the difference between actual and forecasted use, divided by the actual use). A benchmark forecast is calculated by assuming that water use for a given week or month in 1981 is the same as the average for the corresponding period from 1976 to 1980. This method produces an AARE of 14.6 percent for one step ahead forecasts of monthly data and 15.8 percent for weekly data. A cascade model using trend, seasonality and autocorrelation produces forecasts with AARE of about 12 percent for both monthly and weekly data while adding a linear relationship of water use and rainfall reduces the AARE to 8 percent in both cases if it is assumed that rainfall is known during the forecast period. Simple rainfall predictions do not increase the forecast accuracy for water use so the major utility of relating water use and rainfall lies in forecasting various possible water use sequences conditioned on sequences of historical rainfall data. 相似文献
75.
76.
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
77.
78.
刘向葵 《中国环境管理干部学院学报》1999,(4)
用城市生活垃圾经好氧高温制成堆肥,并向其中加入无机化肥和微量元素添加剂可制成有机复合肥。本文简要阐述了好氧高温堆肥的生产工艺,推荐了用垃圾生产有机复合肥的两类配方。 相似文献
79.
80.
我国城市生活垃圾的处理和发展趋势 总被引:6,自引:0,他引:6
城市生活垃圾给城市环境造成了严重污染,威胁了城市居民的生存环境和经济、社会的可持续发展。目前,国内采取的垃圾处理技术主要有卫生填埋、焚烧、堆肥等,热解技术由于具有资源回收率高、二次污染小、综合效益好等优点,越来越适合我国中小城市的垃圾处理。垃圾气化技术的研究成为当今世界的热点。此外,我国对垃圾衍生燃料的研究也刚刚起步。为促进城市持续、稳定的发展,提出了垃圾分类收集、分拣、综合利用垃圾处理技术的措施。 相似文献