电旋风除尘模型实验研究

本研究试图将电除尘器与旋风除尘器组合为一体,以求取得较高的除尘效率,并利用旋转气流实现自动清灰。本文介绍了切向进气直流式电旋风除尘的模型试验,通过实测不同工况下的除尘效率和压力损失,应用经典除尘理论,建立了相应的数学模型。     

SUSPENDED SEDIMENT AND METALS REMOVAL FROM URBAN RUNOFF BY A SMALL LAKE1

ABSTRACT: A small lake in the Chicago Metropolitan Area was from 91 to 95 percent efficient in removing suspended sediment and from 76 to 94 percent efficient in removing copper, iron, lead, and zinc from urban runoff. Sediments accumulated in the lake in the form of an organic-rich mud at an average rate of 20 millimeters per year; this reduced lake storage and covered potential habitat for aquatic organisms. Copper, lead, and zinc concentrations were closely associated with suspended-sediment concentrations and with silt- and clay-sized fractions of lake sediment. Although concentrations of mercury and cadmium were near detection limits in runoff, measurable concentrations of these metals accumulated in the lake sediments.     

WATER POLICIES FOR ENERGY DEVELOPMENT1

ABSTRACF: Examination of a series of studies of the economically efficient water allocations in the Upper Colorado River, Yellowstone River, and Great Basins indicate that water is not a serious general physical constraint on the development of energy resources, so long as public institutions do not hinder the exchange of water rights in markets. Energy development will cause limited impacts on other water-using sectors, principally agriculture. There appears to be little reason to develop large-scale water storage facilities, even during periods of reduced water production. Water storage developments appear to be necessary only when institutional constraints severely restrict water rights markets and transfers.     

An approach for analysing the potential for material efficiency improvement

Material efficiency improvement saves energy and reduces the consumption of primary resources and reduces the volume of waste. In this article an approach for analysing the potential for material efficiency improvement is proposed and discussed. In this approach the product functions performed by the materials and various improvement measures are taken into account. The potential for material saving and associated energy saving is assessed and evaluated economically. In this paper the approach is tested in an analysis of the potential for material efficiency improvement with respect to plastic packaging in the Netherlands. The technical reduction potential is found to be 34 ± 7% (157 ± 30 ktonne virgin plastics). Realization of this potential would improve the energy efficiency of the lifecycle of plastic packaging by 31% (10 PJ in 1988). From our study we conclude that our approach can indeed be used to investigate the potential for material efficiency improvement. However, a reliable technical and particularly an economical assessment of reduction measures cannot be made until more detailed data become available.     

Metals recycling in the United States

Twenty-two metals for which secondary recovery is important, in terms of quantity and/or value, were compared and ranked for rate and efficiency of recycling, and availability of recycled metal. In general, their recycling rates trended upward over the period 1970–1993. Iron, aluminum, copper, gold, platinum, and lead accounted for most of the value of all secondary metal produced, while iron and steel dominated in terms of quantity produced and exported. The factors most influential on recycling rates are profitability, public support, organization of infrastructure, sortability, legislative support, and scrap purity. The share of supply accounted for by secondary metals is expected to surpass that of primary metals sometime in the next decade.     

Estimation of the shadow prices of pollutants with production/environment inefficiency taken into account: a nonparametric directional distance function approach

This paper deals with the estimation of the shadow prices of pollutants with a nonparametric directional distance function approach, where the inefficiency involved in the production process is taken into account unlike the previous studies. The directional vector, which is critical to the estimation and subject to the criterion for an appropriate efficiency rule proposed here, is calculated by using the annual plans of power plants in terms of production and environment. In the empirical study for Korea's electric power industry during the period of 1990-1995, we find that the average shadow prices of sulfur oxides (SOx), nitrogen oxides (NOx), and total suspended particulates (TSP) are approximately 10% lower than those calculated under the assumption of full efficiency. The methodology we propose and the findings obtained in the empirical study allow us to undertake better decision-making over a broad range of environmental policy issues.     

EVALUATING INTERDEPENDENT WATERSHED CONSERVATION AND GROUND WATER MANAGEMENT REFORMS1

Abstract: Conserving the watershed can help to preserve ground water recharge. Preventing overuse of available water through pricing reforms can also substantially increase the value of an aquifer. Inasmuch as users are accustomed to low prices, efficiency pricing may be politically infeasible, and watershed conservation may be considered as an alternative. We estimate and compare welfare gains from pricing reform and watershed conservation for a water management district in Oahu that obtains its water supply from the Pearl Harbor aquifer. We find that pricing reform is welfare superior to watershed conservation unless the latter is able to prevent very large recharge losses. Watershed conservation that yields net gains in combination with pricing reform may cause net losses without the pricing reform. If adoption of watershed conservation delays the implementation of pricing reform, the benefits of the latter are significantly reduced.     

气相色谱仪检测溶解气H_2、He最佳观测条件的选择

通过色谱柱、固定相以及载气流速的选择性实验 ,提高了气相色谱仪在观测地下水中H2 、He分离效能和检测效能。本文对此作介绍 ,以期对使用气相色谱仪进行地下水H2 、He观测的台站能有所启发和借鉴     

TECHNICAL AND INSTITUTIONAL ASPECTS OF SEWAGE EFFLUENT-IRRIGATION WATER EXCHANGE,TUCSON REGION1

ABSTRACT .Many growing municipalities near irrigated agriculture are advocating a transfer of water now utilized for irrigation to municipal use. Alternatives are presented whereby this water can be transferred to municipal use in exchange for treated sewage effluent. The irrigation water would in effect be cycled through the municipal system prior to use on the farms. A case study of the Tucson region illustrates the relevant legal, economic and technical aspects. Effluent could be delivered to irrigators in Avra Valley at a cost less than that now paid for water pumped from declining water tables. In return the City of Tucson could import ground water now being used for irrigation through an existing pipeline which presently cannot be used because of a court injunction obtained by the irrigators. It appears that such an exchange agreement could be made without modification of existing statutory law. Similar exchange arrangements may prove to be feasible in other regions containing irrigated agriculture. Increased efficiency of water use can be achieved avoiding external effects which commonly arise in a direct transfer and are difficult to evaluate. High quality water is allocated to municipal use whereas nutrient-rich sewage effluent is transferred to irrigation.     

Integrated energy management strategy of powertrain and cooling system for PHEV

ABSTRACT

Energy management strategy (EMS) is crucial in improving the fuel economy of plug-in hybrid electric vehicle (PHEV). Existing studies on EMS mostly manage powertrain and cooling system separately which cannot get the minimum total energy consumption. This paper aims to propose a novel EMS for a new type of dual-motor planetary-coupled PHEV, which considers cooling power demand and effect of temperature on fuel economy. Temperature-modified engine model, lithium-ion battery model, two motors, and cooling system models are established. Firstly, the separated EMS (S-EMS) is designed which manages powertrain and cooling system separately. Sequentially, after the analysis of thermal characteristics of the powertrain and cooling system, the thermal-based EMS (T-EMS) is then proposed to manage two systems coordinately. In T-EMS, cooling power demand and the charging/discharging energy of motors are calculated as equivalent fuel consumption and integrated into the object function. Besides, a fuzzy controller is also established to deicide the fuel-electricity equivalent factor with consideration of the effect of temperature and state of charge on powertrain efficiency. Finally, the hardware-in-loop experiment is carried out to validate the real-time effect of EMS under the New European Driving Cycle. The result shows that cooling power demand and temperature can significantly affect the fuel economy of the vehicle. T-EMS shows better performance in fuel economy than S-EMS. The equivalent fuel consumption of the cooling system of T-EMS decreases by 27% compared with that of S-EMS. The total equivalent fuel consumption over the entire trip of PHEV using T-EMS is reduced by 9.7%.