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91.
基于灰色系统理论的煤与瓦斯突出预测 总被引:5,自引:5,他引:5
为了对煤与瓦斯突出事故进行有效的预防与控制 ,笔者应用灰色系统理论中的灰色聚类评估方法 ,对矿井的煤与瓦斯突出进行了预测。经实例证明 ,与常用的预测方法相比 ,灰色聚类预测方法具有能动态预测、预测准确等优点。该方法将影响突出的多个因素综合系统的来考虑 ,跳出了常规预测方法只依靠单一指标进行预测的圈子 ,提高了预测的准确性。研究结果表明 ,该方法能准确地反映矿井煤与瓦斯突出规律 ,是一种新的煤与瓦斯突出预测的方法 相似文献
92.
珠江三角洲经济区污水系统设计原则 总被引:2,自引:0,他引:2
分析了珠江三角洲经济区水环境现状;阐述了城市污水分散处理与集中处理的利弊;指出污水深度处理与回用是形成良性水循环的有效途径,更是经济可持续发展的必然要求;通过对已建排水系统存在问题的分析,探讨了珠江三角洲经济开发区污水系统的设计原则,认为污水系统规划要改变传统设计方法,应方便再生水回用,由经济、技术、地理等综合因素确定排水分区、污水厂厂址与数量,选择适合各排水区域水质水量的工艺流程,预留污水厂与再生水回用管线分期发展的空间,应优先选用国产污水处理设备,尽可能维持城市河涌自然生态。 相似文献
93.
事物安全演化过程的基本理论研究 总被引:1,自引:1,他引:1
何学秋 《中国安全生产科学技术》2005,1(1):5-10
安全状态的演化过程是事物发展变化过程的重要组成部分.事物的安全演化过程符合从量变到质变的原理,即服从"安全流变-突变"规律.基于事物"安全流变-突变"规律,建立理论模型,并分析和描述事物的安全演化过程.事物"安全流变-突变"规律的研究为揭示事物的安全本质规律奠定了基础. 相似文献
94.
The challenges of sustainability in mining regions: The coal mining region of Santa Catarina, Brazil 总被引:1,自引:0,他引:1
Throughout history, mining communities have invariably found themselves striving for a good quality of life and a long‐term future. In the 21st century, problems of maintaining the economic vitality of mining regions are now compounded by concerns about the biophysical integrity of the local environment. In regions of the world where the economic viability of the resource is marginal and achieving a reasonable quality of life is a daily struggle, sustainable mining may seem to be a dubious prospect at best. Yet the twin imperatives of global political forces and burgeoning environmental concerns are requiring industry, governments and other interests to re‐conceptualize the way in which mining takes place in communities. Although mining itself may not be seen as an industry that contributes to the achievement of environmental objectives, it could — with careful planning — be used as a tool to foster a more sustainable and healthier community. This argument is considered in the context of the coal mining region of Santa Catarina, Brazil. 相似文献
95.
Liang Lu Yuqi Jin Hongmei Liu Xiaojun Ma Kunio Yoshikawa 《Waste management (New York, N.Y.)》2014,34(1):79-85
Nitrogen evolution was studied during the co-combustion of hydrothermally treated municipal solid wastes (HT MSW) and coal in a bubbling fluidized bed (BFB). HT MSW blending ratios as 10%, 20% and 30% (wt.%) were selected and tested at 700, 800, 900 °C. Emissions of NO and N2O from blends were measured and compared with the results of mono-combustion trials. Moreover, concentrations of precursors like NH3 and HCN were also quantified. The results are summarized as follows: NO emissions were predominant in all the cases, which rose with increasing temperature. The blending of HT MSW contributed to the NO reduction. N2O emissions decreased with temperature rising and the blending of HT MSW also presented positive effects. At 30% HT MSW addition, both NO and N2O emissions showed the lowest values (391.85 ppm and 55.33 ppm, respectively at 900 °C). For the precursors, more HCN was detected than NH3 and both played important roles on the gas side nitrogen evolution. 相似文献
96.
Mitigation of eutrophication, intensified by excessive nutrient load discharge in wastewaters regulated by restrictive legal requirements, remains one of today’s most important global problems. Despite implementation of the Water Framework Directive, the Urban Wastewater Directive and the HELCOM recommendations, the actual condition of surface water is still not satisfactory. In response to the above, the study presents an alternative approach for surface water protection against eutrophication based on the selection of appropriate nutrient removal technologies. An activated sludge model simulation was used to enable the identification of environmentally justified nutrient removal systems with lowest eutrophication potential of treated wastewater conditioned by bioavailable nutrient forms content. Based on the outcome of the study, the 3-stage Bardenpho system was identified as the most efficient for bioavailable phosphorus removal, while the Johannesburg system proved to have the highest efficiency for bioavailable nitrogen removal. The proposed eutrophication mitigation approach underlines the need for a reconsideration of current legal regulations which ignore nutrient bioavailability and key eutrophication limiting factors. 相似文献
97.
为了处理制药企业废水中吲哚类有机污染物,采用好氧MBBR(移动床生物膜反应器)工艺对含吲哚废水进行了试验研究,通过考察HRT、曝气量、吲哚冲击负荷等工艺条件对吲哚、COD和NH_4~+-N等去除效果的影响,确定了好氧MBBR反应器的最佳工艺条件。实验结果表明,在HRT在6~18 h变化时,MBBR工艺对吲哚去除率在8 h以上时达到100%,COD去除率在8 h达到89.65%,而NH_4~+-N去除率在12 h达到最高。在曝气量为0.1~0.12 m L/min时,MBBR工艺对COD和NH_4~+-N去除率分别为88.88%~92.95%和65%~66.83%。进水吲哚浓度25~65 mg/L变化时,好氧MBBR对吲哚去除率保持在100%,而对COD和NH_4~+-N去除率也保持在80%和40%以上,表明好氧MBBR工艺在处理难降解有机污染物方面具有显著优势。 相似文献
98.
Kuangxin Zhou Matthias Barjenbruch Christian Kabbe Goulven Inial Christian Remy 《环境科学学报(英文版)》2017,29(2):151-159
Phosphorus (P) is a limited resource, which can neither be synthesized nor substituted in its essential functions as nutrient. Currently explored and economically feasible global reserves may be depleted within generations. China is the largest phosphate fertilizer producing and consuming country in the world. China''s municipal wastewater contains up to 293,163 Mg year of phosphorus, which equals approximately 5.5% of the chemical fertilizer phosphorus consumed in China. Phosphorus in wastewater can be seen not only as a source of pollution to be reduced, but also as a limited resource to be recovered. Based upon existing phosphorus-recovery technologies and the current wastewater infrastructure in China, three options for phosphorus recovery from sewage sludge, sludge ash and the fertilizer industry were analyzed according to the specific conditions in China. 相似文献
99.
Effluent dissolved organic nitrogen (DON) is problematic in nutrient sensitive surface waters and needs to be reduced to meet demanding total dissolved nitrogen discharge limits. Bioavailable DON (ABDON) is a portion of DON utilized by algae or algae + bacteria,while biodegradable DON (BDON) is a portion of DON decomposable by bacteria. ABDON and BDON in a two-stage trickling filter (TF) wastewater treatment plant was evaluated using three different microalgal species, Selenastrum capricornutum, Chlamydomonas reinhardtii and Chlorella vulgaris and mixed cultured bacteria. Results showed that up to 80% of DON was bioavailable to algae or algae + bacteria inoculum while up to 60% of DON was biodegradable in all the samples. Results showed that C. reinhardtii and C. vulgaris can be used as a test species the same as S. capricornutum since there were no significant differences among these three algae species based on their ability to remove nitrogen species. 相似文献
100.
山林地表慢渗系统处理农村生活污水厂尾水研究 总被引:1,自引:0,他引:1
利用山区污水处理厂周边森林植被构建慢速渗滤污水处理系统,用来处理山区农村生活污水厂尾水。结果表明,慢渗系统能够深度净化污水尾水,对COD_(Cr)、NH_3-N、NO_3-N、TN、TP的平均去除率分别为23.8%、40.2%、14.3%、11.3%和23.6%。并且土层越深,COD_(Cr)、TN、TP浓度越低,相应的去除率越高,而NO_3-N、TN去除率则呈降低趋势;山体坡度越大,COD_(Cr)、氨氮浓度有升高趋势,硝态氮、TN、TP有降低趋势;而坡长越大,COD_(Cr)、NH_3-N、NO_3-N、TN浓度有降低趋势,TP有升高趋势。此外,植被类型对水样化学性质有一定影响,竹林更利于COD_(Cr)、NH_3-N、TP浓度的降低,针阔混交林更利于NO_3-N、TN浓度的降低。 相似文献