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1.
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project.  相似文献   

2.
ABSTRACT. The Orange County Water District has conducted studies in waste water reclamation and groundwater recharge since 1965. The work has been done in three phases: (1) Study in both laboratory and pilot-scale units on the feasibility of reclaiming trickling filter effluent for injection through wells into confined aquifers; (2) long-term injection study to determine the fate of injected reclaimed water and to observe the performance of a multi-casing injection well; (3) testing alternative treatment methods in a 25,000 gpd pilot plant to solve the water quality problems which developed during the injection study. The reclaimed trickling filter effluent was found to be injectable and did not cause excessive well clogging. The multi-casing injection wells performed very satisfactorily. The reclaimed water would be acceptable for domestic use after travel through 500 feet of a confined aquifer in that bacteria, virus and toxic material were consistently absent. However, the odor and taste which persisted in the injected reclaimed water and the high concentration of dissolved inorganics are undesirable characteristics. Methods to eliminate the odor are being tested at the present time. A cooperative project with the Office of Saline Water is under way to develop a source of desalted seawater to blend with reclaimed waste water.  相似文献   

3.
砂过滤器是一种传统而高效的水处理设备,广泛应用于钢铁企业循环水系统。目前钢铁企业最常用的砂滤器是高速或中速砂过滤器。本文结合新型浅层砂过滤器的应用,对余压过滤系统技术(余压全滤、余压旁滤)应用于钢铁企业循环水系统进行了分析,并对具体的设计方法进行了详细的介绍,可供实际生产和工程建设参考。  相似文献   

4.
ABSTRACT: The cost of water service to rural residents is very high compared to urban areas. This is true even after subsidization by Farmers Home Administration (FmHA) loans and grants. Capital cost data on 44 projects financed by the Ohio office of the FmHA during the period August 1968 to January 1977 are used to derive cost equations for 26 components of rural water distribution systems. These components represent 92 percent of the capital cost of the pipeline distribution systems studied. The data can be used to economically design rural water supply systems from a capital cost viewpoint. More data are needed on operation and maintenance costs as well as central and cluster well costs before totally economic system designs can be undertaken.  相似文献   

5.
ABSTRACT. Federal guidelines for the establishment of water quality standards prohibit degradation of the properties of all or part of the nation's aquatic resources. It is probably correct that streams, lakes and aquifers should be free of toxic substances while non-poisonous deposits should be abated. However, an extreme opposing position is held by some proponents of pollution who intend to continue discharging waste materials until forced to stop. Although it would seem otherwise, the underlying problem is that polluters' points of altercation possess merit in particular instances. Accordingly, efficient abatement will require that appropriate laws be formulated in such a manner that the nature of economic reasons for the disposal of waste materials be disclosed. Moreover, the technological ability to create byproducts from these particular elements or compounds can advance only over time. This, coupled with the fact that scientists have not developed inexpensive treatment methods which are totally effective, justifies more flexible formal regulations. Excessive rigidity of standards could impose a burden on polluters that is greater than the cost to society which the damaging firm or individual is generating. On the other hand, uniform rules in some cases could be considered so lenient as to allow flagrant contamination which unduly injures downstream users.  相似文献   

6.
ABSTRACT: Growth in the commercial sector of the economy and the increased importance of total waste water volumes in design have created a need for methods of estimating commercial water demand. The results of a multiple correlation analysis and a principal components analysis suggest that commercial water demand is a function of the following three primary constructs: an employee water use factor, a customer layout factor, and a customer water facility factor. Three easily measured variables were used to represent these primary constructs: gross store area, length of display windows, and the number of drinking fountains, respectively. Prediction equations relating water use and the three variables were derived and can be used by planners in estimating commercial water use.  相似文献   

7.
ABSTRACT: A new insoluble N-halamine polymeric disinfectant material has been tested in a water filter application to determine (1) its tendencies to leach undesirable decomposition products, (2) its range of potential applicability, and (3) its regenerability. In flowing water tests, poly-1,3-dichloro-5-methyl-5-(4‘-vinylphenyl)hydantoin (Poly-I) leached only small amounts of total organic carbon, free and total chlorine, anions, and volatile organics such as trihalomethanes. Furthermore, Poly-I provided bactericidal efficacy over the pH range 4.5 to 9.5 and at temperatures as high as 37°C. Poly-I is deactivated by reducing agents such as sodium thiosulfate and by ethanol; following deactivation, it can be regenerated by exposure to flowing aqueous free chlorine. Poly-I appears suitable for use as a biocidal filter for small potable and recreational waters, for it is effective over a wide pH and temperature range and is readily regenerable. It would not be useful, however, for disinfection of large bodies of water such as in city treatment plants because of its cost and the large amount of the material that would be necessary.  相似文献   

8.
ABSTRACT Providing adequate water supplies of good quality is becoming a serious problem in many areas of the United States. Some of the alternatives proposed for meeting the growing shortage of clean-water or cheap-water are reallocation, reuse, and importation. This paper outlines a methodology to assess all of these water supply alternatives by examining the amount and time-staging for development of water sources. In conceptualizing the problem, sources of supply are classified in three categories: primary or base supplies, secondary or effluent supplies, and supplementary or imported supplies. A model of the water system is formulated as a “transportation problem” in linear programming depicting the possible sources of supply which can be used to satisfy the requirements of various water users. The optimizing objective in the model is to minimize the cost of water under various assumptions for operating the system. A case study of the Salt Lake Qty, Utah, area is used to illustrate the application of the model in obtaining optimal water supply allocations for projected future demands. Assessment of alternatives in the study include redistribution of supplies, time-staging of supplies and related treatment facilities, and sensitivity of allocations to changes in costs.  相似文献   

9.
ABSTRACT: Linear programming is the simplest of all the optimization techniques used in regional water quality management studies; but the technique can optimize only one goal. When there are multiple goals with the same or different priorities, goal programming is a useful decisionmaking tool. This paper illustrates the application of goal programming to a regional water quality management problem where the following two goals are considered: (1) minimize the total cost of waste treatment, and (2) maintain the water quality goals (dissolved oxygen) close to the minimum level stated in the stream standards.  相似文献   

10.
ABSTRACT: In the near future, groundwater storage of imported water may become increasingly important as sites for surface storage are less available. This article explores the potential economic costs and benefits of groundwater storage. The costs include capital outlays, maintenance costs, land costs, legal costs, energy costs, and opportunity costs. The benefits include land cost savings, prevention of subsidence, aquifer protection, and higher economic use of surface lands that might be covered by a reservoir.  相似文献   

11.
ABSTRACT: Historically, storm water management programs and criteria have focused on quantity issues related to flooding and drainage system design. Traditional designs were based on large rainfall‐runoff events such as those having two‐year to 100‐year return periods. While these are key criteria for management and control of peak flows, detention basin designs based on these criteria may not provide optimal quality treatment of storm runoff. As evidenced by studies performed by numerous public and private organizations, the water quality impacts of storm water runoff are primarily a function of more frequent rainfall‐runoff events rather than the less frequent events that cause peak flooding. Prior to this study there had been no detailed investigations to characterize the variability of the more frequent rainfall events on Guam. Also, there was a need to develop some criteria that could be applied by designers, developers, and agency officials in order to reduce the impact of storm water runoff on the receiving bodies. The objectives of this paper were three‐fold: (1) characterize the hourly rainfall events with respect to volume, frequency, duration, and the time between storm events; (2) evaluate the rainfall‐runoff characteristics with respect to capture volume for water quality treatment; and (3) prepare criteria for sizing and designing of storm water quality management facilities. The rainfall characterization studies have provided insight into the characteristics of rainstorms that are likely to produce non‐point source pollution in storm water runoff. By far the most significant fmdings are the development of a series of design curves that can be used in the actual sizing of storm water detention and treatment facilities. If applied correctly, these design curves could lead to a reduction of non‐point source pollution to Guam's streams, estuaries, and coastal environments.  相似文献   

12.
ABSTRACT: A computer program (MAPS - Methodology for Areawide Planning Studies) has been developed by the U.S. Army Corps of Engineers, Waterways Experiment Station to assist planners in producing a comprehensive array of alternatives without sacrificing the detail and accuracy of the analyses. MAPS is a set of computer based models which can be used to simulate the water resource alternatives and to develop planning level design and cost estimates. Two application examples are discussed. The Salinas-Monterey (California) Urban Study sought to identify and determine cost of combinations of water source, transmission, and treatment to meet an array of water needs in future years. The Nashville (Tennessee) Urban Study had similar objectives but the output was prepared on a service area basis for more than 40 such units. Using MAPS it was possible to prepare planning level design and cost estimates for a very large number of alternatives.  相似文献   

13.
ABSTRACT: This study was undertaken to investigate the cost effectiveness of selected arsenic avoidance methods. Annual costs of reverse osmosis (RO), activated alumina (AA), bottled water, and rented and purchased water coolers for various household sizes in Maine were compared. Relative ranking of systems shows that RO ($411 annually) is the most cost effective, followed by AA ($518) and one‐gallon jugs of water ($321 to $1,285), respectively, for households larger than one person. One‐gallon jugs ($321) followed by 2.5‐gallon jugs ($358) of water were found to be the most cost effective for households of one person or for households with arsenic III concentrations of 0.02 to 0.06 mg/L and arsenic V concentrations of 0.08 to 1.0 mg/L. Point‐of‐entry systems and water coolers were not found to be cost effective under any of the study's conditions. The research reported here will help states make more definitive treatment recommendations to households regarding the cost effectiveness of alternative treatment systems to reduce arsenic concentrations below 0.01 mg/L. While arsenic removal technologies are improving, which enhances removal rates and reduces costs, the major insights from this analysis appear to be reinforced by technological improvements.  相似文献   

14.
Due to ever increasing quantities of waste materials and industrial by-products, solid waste management is the prime concern in the world. Scarcity of land-filling space and because of its ever increasing cost, recycling and utilization of industrial by-products and waste materials has become an attractive proposition to disposal. There are several types of industrial by-products and waste materials. The utilization of such materials in concrete not only makes it economical, but also helps in reducing disposal concerns. One such industrial by-product is waste foundry sand (SFS). Waste foundry sand is a by-product of ferrous and nonferrous metal casting industries. Foundries successfully recycle and reuse the sand many times in a foundry. When the sand can no longer be reused in the foundry, it is removed from the foundry and is termed as waste foundry sand.Published literature has shown that WFS could be used in manufacturing Controlled Low-Strength Materials (CLSM) and concrete. This paper presents an overview of some of the research published on the use of WFS in concrete. Effect of WFS on concrete properties such as compressive strength, splitting tensile strength, modulus of elasticity, freezing-thawing resistance, and shrinkage are presented.  相似文献   

15.
ABSTRACT: Temporary transfers of water for dry year water supply are analyzed for cost and operational feasibility. The temporary transfer is implemented as part of a water rights option agreement (WROA) between a lesson and a lessee. First, engineering analysis determines the technical feasibility and operations plan under the Colorado doctrine of prior appropriation. The cost of the WROA to a water utility is estimated. Other considerations in the agreement are discussed. The WROA is compared to other dry-year supply alternatives using a water system simulation model to obtain expected cost and operational performance characteristics.  相似文献   

16.
ABSTRACT: A model consisting of closed water reuse and productive use of various types of wastes for energy generation is presented. The sewage after treatment would be used as the cooling water for power plants, and the condenser discharge therefrom be used as heating water for sludge digesters. The water is then purified for municipal water supply for continuous use. The advantages of this system are that water resources and energy are conserved while various types of wastes including waste heat are controlled. With a preliminary system analysis, it appears that the design for power plant based on the total heating value of wastes and digester capacity based on sewage sludge generation is feasible in terms of acquisition and full utilization of various types of wastes as generated in a single metropolitan area. The system as shown in this design is in balance among various factors such as the generation rate of municipal refuse, municipal sewage, waste heat in the condenser discharge, and raw sewage sludge.  相似文献   

17.
An analytical solution is developed to predict the BOD and DO profiles in a stream having several outfalls of waste and intakes of water. The model also incorporates continuous addition and removal of BOD and DO along the stream. A steady state one dimensional dispersion model is used to describe the transport of BOD and DO in a stream. Changes in stream properties along the length are considered by dividing the stream into several segments and changing the parameters of the BOD and DO equations as needed in each segment. By applying continuity equations at the boundaries of these segments and equilibrium conditions at either ends of the infinitely long stream, the arbitrary constants in the solutions to the differential equations for BOD and DO can be determined. Some applications of the results in studying water pollution problems are illustrated.  相似文献   

18.
: This paper presents solutions to the one-dimensional, transient conservation of mass equations for the coupled biochemical oxygen demand-dissolved oxygen (BOD-DO) reactions, based on the principle of superposition, for continuously discharging plane sources. The solutions are applied within the framework of a continuous simulation model to allow the derivation of water quality frequency curves and frequency histograms of consecutive hourly dissolved oxygen violations, for any desired standard. Receiving water response is determined for waste inputs from urban wet weather, dry weather, and upstream sources. An application to Des Moines, Iowa, and Des Moines River indicated that urban storm water impacts on the stream can be masked in the cumulative frequency curve representation, but the benefits of storm water control are clearly shown in frequency histograms of the duration of consecutive stream standard violations.  相似文献   

19.
ABSTRACT: Low flow augmentation from multipurpose reservoirs may yield significant water quality benefits. Cost allocation assigns a portion of reservoir expense to water quality consumers, waste water dischargers who benefit from increased receiving flow. Whereas such allocation currently is not authorized for Federal projects, the procedure is increasingly appropriate for efficient multiobjective management. Waste water treatment costs, multipurpose reservoir costs, and water quality are modeled for Oregon's Willamette River. Water quality is expressed as a function of treatment and augmentation levels. Treatment cost necessary to achieve a given water quality without augmentation less treatment cost with augmentation is an alternative cost of water quality maintenance. With a cost allocation procedure, this alternative cost is used to determine water quality's share of reservoir cost. Under current conditions, water quality beneficiaries could be charged approximately seven percent of annualized reservoir expense. This charge is one-fourth the expense of additional treatment facilities required were augmentation not provided.  相似文献   

20.
ABSTRACT: In the last two decades the federal government has provided substantial capital to construct rural water distribution systems. Loans at subsidized interest rates and front-end grants through the Farmers Home Administration have been the main source of this capital. Recent federal policy redirections have reduced substantially the availability of grants and subsidized loans. Because of design and material differences, capital cost estimates from urban systems are not uniformly applicable to rural water services. This study presents an econometric analysis of capital costs, using Illinois rural water system construction contract bids. Cost equations by systems components representing 90 percent of capital costs are estimated. The type of information developed here can be used in initial planning and optimization design models contributing to the efficient provision of rural water services.  相似文献   

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