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991.
喀斯特峡谷区工程性缺水原因及解决途径——以贵州省花江峡谷示范区为例 总被引:3,自引:0,他引:3
喀斯特峡谷区河深坡陡,地下水深埋,水资源利用难度大,加之经济和水利工程薄弱,是贵州省工程性缺水的典型区域。通过对花江峡谷示范区工程性缺水的原因剖析,提出一系列解决工程性缺水问题的措施,如雨水收集、表层喀斯特水和基岩裂隙水的开发利用、节水、加强对水利工程设施的管理和维护、加大水利投入以及提高植被覆盖率等,这对解决喀斯特峡谷及类似区域的工程性缺水问题有一定的指导和参考意义。 相似文献
992.
Environmental assessment of garden waste management in the Municipality of Aarhus, Denmark 总被引:1,自引:0,他引:1
An environmental assessment of six scenarios for handling of garden waste in the Municipality of Aarhus (Denmark) was performed from a life cycle perspective by means of the LCA-model EASEWASTE. In the first (baseline) scenario, the current garden waste management system based on windrow composting was assessed, while in the other five scenarios alternative solutions including incineration and home composting of fractions of the garden waste were evaluated. The environmental profile (normalised to Person Equivalent, PE) of the current garden waste management in Aarhus is in the order of −6 to 8 mPE Mg−1 ww for the non-toxic categories and up to 100 mPE Mg−1 ww for the toxic categories. The potential impacts on non-toxic categories are much smaller than what is found for other fractions of municipal solid waste. Incineration (up to 35% of the garden waste) and home composting (up to 18% of the garden waste) seem from an environmental point of view suitable for diverting waste away from the composting facility in order to increase its capacity. In particular the incineration of woody parts of the garden waste improved the environmental profile of the garden waste management significantly. 相似文献
993.
本文采用流动注射分析技术在线测定水中阴离子表面活性剂,使用的仪器为德国BRAN+LUEBBE公司自动分析仪。方法在0.050~0.400mg/L范围内,可以获得较好的线性方程,相关系数〉0.9990,检出限为0.015mg/L,水样的回收率在92%~109%,此方法符合水质测定阴离子表面活性剂的要求。并对影响阴离子表面活性剂测定的因素进行探讨。 相似文献
994.
A method for quality screening is suggested to detect volatile impurities in inorganic coagulants that are used for drinking water treatment. Static headspace gas chromatography with mass spectrometry detection (HS–GCMS) is sensitive and selective to detect volatiles in low concentrations. This study has discovered that volatile organic impurities are detectable in ferric and aluminium-based coagulants which are used for drinking water treatment. For ferric chloride, 2-propanol was detected at a level of 17–24 μg ml−1, acetone at 0.7–1.7 μg ml−1, 1,1,1-trichloroacetone at 0.02–0.04 μg ml−1, trichloromethane at 0.01–0.02 μg ml−1 and toluene at 0.01–0.12 μg ml−1. For ferric chloride sulfate, acetone was detected at a level of 0.12 μg ml−1, 1,1,1-trichloroacetone at 0.06–0.08 μg ml−1, trichloromethane at 0.13–0.23 μg ml−1, bromodichloromethane at 0.04–0.06 μg ml−1 and dibromochloromethane at 0.04–0.05 μg ml−1. For aluminium hydroxide chloride, only trichloromethane was detectable, but below the method detection limits (MDL). Although the concentrations of these impurities in commercial coagulants are low, this observation is important and should have impact on water industries for them to pay attention to the chemicals they are using for drinking water production. 相似文献
995.
996.
城市生活垃圾的成分及特性随着季节和人类在不同季节的生活习惯而变化,针对我国北方城市研究了一年中不同季节的城市生活垃圾成分特点,对影响厌氧发酵过程的相关成分如总有机碳(TOC)、总氮(TN)、蛋白质、脂肪和还原糖等进行了测定分析。通过厌氧消化实验,测得不同季节城市生活垃圾pH值、日产气量、沼气甲烷含量、甲烷累积量、挥发性脂肪酸(VFAs)和氧化还原电位(ORP)等参数的变化规律,分析相应变化的影响因素。结果表明,二、三季度的含水率分别为64.81%和67.50%,高于一、四季度,一季度发酵原料中蛋白质和脂肪含量分别为12.56%和8.86%,明显高于其他3个季度。一季度甲烷累积量最高,达到17616mL,单位发酵原料的产气量为204.8mL/g,也是4个季度中最高的,说明蛋白质、脂肪等有机成分含量对厌氧发酵过程及结果影响比较明显。为进一步的城市生活垃圾厌氧消化制取生物燃气的工艺条件提供依据。 相似文献
997.
Dechlorination of polyvinyl chloride in NaOH/ethylene glycol solution by microwave heating 总被引:1,自引:1,他引:0
This study investigated the dehydrochlorination of flexible polyvinyl chloride (PVC) containing 59.2% PVC, 29.7% dioctyl phthalate
(DOP), and approximately 12% stabilizers. Flexible PVC was treated with NaOH/ethylene glycol (NaOH/EG) solutions at NaOH concentrations
in the range 0.5–4 mol/l and was heated in a microwave heater at a temperature between 100° and 160°C for 0–30 min. All chlorides
were completely eliminated by internal heating at 160°C using microwaves for 10 min in a 1 mol/l NaOH/EG solution, and the
residue was made up of hydrocarbons. The weight loss rate reached a maximum of 74.7% at a temperature of 160°C. It was discovered
that the use of microwaves significantly shortened the reaction time compared to using conventional electric heaters or other
external heating systems and also allowed the use of lower concentrations of NaOH.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
998.
999.
以天然矿物质沸石、细砂及煤渣取代传统滤料构建复合基质生态床,表面种植景观植物,采用下向流-上向流运行方式修复北方景观水体。分别进行静态实验及不同循环速率下的动态实验,考察对水体污染物去除过程。结果表明,2种运行方式下对水体NH+4-N去除率都在85%以上,其中以1 h为循环周期的运行方式去除率达97%,较静态提高12.8%;TN去除率最高为84%;TP去除不稳定,过程缓慢。煤渣层对NH+4-N的去除效果差,硝化作用不彻底与反硝化作用的加强使下层出水NH+4-N 、NO-2-N及NO-3-N浓度均高于上层。提高循环速率有利于对氮的去除。 相似文献
1000.
Evaluation of a classification method for biodegradable solid wastes using anaerobic degradation parameters 总被引:1,自引:0,他引:1
Wei Zheng Khamphe Phoungthong Fan Lü Li-Ming Shao Pin-Jing He 《Waste management (New York, N.Y.)》2013,33(12):2632-2640
We studied the biochemical and anaerobic degradation characteristics of 29 types of materials to evaluate the effects of a physical composition classification method for degradable solid waste on the computation of anaerobic degradation parameters, including the methane yield potential (L0), anaerobic decay rate (k), and carbon sequestration factor (CSF). Biochemical methane potential tests were conducted to determine the anaerobic degradation parameters of each material. The results indicated that the anaerobic degradation parameters of nut waste were quite different from those of other food waste and nut waste was classified separately. Paper was subdivided into two categories according to its lignin content: degradable paper with lignin content of <0.05 g g VS?1, and refractory paper with lignin content >0.15 g g VS?1. The L0, k, and CSF parameters of leaves, a type of garden waste, were similar to those of grass. This classification method for degradable solid waste may provide a theoretical basis that facilitates the more accurate calculation of anaerobic degradation parameters. 相似文献