村镇供水管网优化设计探讨

如何合理确定村镇供水管网敷设方案，关系到整个供水系统的安全性和可靠性。通过生成树变化法，将环状管网转化成树状管网，确定供水管网中最短供水路线，再计算最短供水路线下的最低综合费用、供水系统的经济管径，以确定最优管道敷设方案。根据该方法对四川省某镇供水系统进行了设计。     

招标信息

工程概况：该项目建设地点位于江苏省启东市寅阳镇、惠萍镇等地。备注：该项目为新建工程,污水处理厂区已建设完成,目前正在对配套管网工程（包含5个泵站）招设计单位,业主要求设计单位在一个月内完成设计方案,预计2011年春节后对施工单位进行招标,项目建设周期尚未确定。感兴趣的相关单位可提前联系业主,以便获得合作机会。     

招标信息

正一、污水处理厂配套管网工程项目性质:新建项目进展阶段:初步设计项目预算:约2.7亿元资金来源:申请上级资金支持及市财政资金相关工程:土建施工、管网工程、绿化工程等。相关设备:管材管件等。工程概况:该项目为新建污水处理厂配套管网工程,建设地点位于河北省,按2015年处理污水达到12万立方米/天,出水水质达到一级A标准建设。远期按2020年处理污水24万立方米/天标准建设,同时新建泵站2座,改建泵站1座,管网总长度约47.99公里,计划采用PE管、球墨铸铁管,管径大小待施工图设计完成后确定,目前尚     

城市“马路拉链“治理对策研究

城市"马路拉链"现象不仅带来了经济和环境损失,还诱发更深层次的社会和谐损失.该现象的产生源于错误的政绩观、城市地下管网管理体制弊端及针对"马路拉链"问题的监督和约束机制之不健全.为此提出三个治理对策:其一,摆正城市公共服务主客体基本立场,树立正确的政绩观;其二,从提高城市道路规划水平入手,对城市地下管网实施系统治理;其三,建立健全"马路拉链"监督与约束机制.     

招标信息

正一、给水管网工程项目性质:新建项目进展阶段:施工图审查总投资额:约7000万元(工程投资6000万元)资金来源:申请省循环经济专项资金及地方自筹相关工程:管网工程、土建工程。相关设备:格栅、工艺设备、泵类设备、仪器仪表、球墨铸铁管、格栅。工程概况:该项目为给水管网工程,主要用于工业厂区供水,建设地点位于青海省,新建供水管网77.15公里及配套附属设施,敷设方式为地下深埋,2米深,1~3米宽(根据挖方确定),每根管长为6米,管的直径为     

秦皇岛市海港区城市排水设施建设与水体保护

城市排水设施的健全对水体保护具有重要作用,秦皇岛市海港区在1999年以前由于排水设施严重落后,管网、泵站能力和污水处理能力严重不足,导致大部分生活污水和工业废水未经处理直接排放,对河流及附近海域造成了严重污染.经过近6年来的大规模排水设施建设,逐渐具备了比较完善的排水管网体系,污水处理能力完全能够满足要求,为有效进行水体保护发挥了重要作用.     

对某高层酒店建筑给水和消火栓系统设计的体会与思考

生活给水系统设计时,将室内外给水管网分成两套,结合实际情况从安全、经济以及维护管理等因素考虑,在地下室布置成立体双环状给水系统;生活热水采用一台容积式浮动盘管热交换器换热供给热水;从理论上论证了组合型消防栓箱在本工程中的适用性和优越性,提出可将灭火器和消火栓位置设于一处的观点供大家在设计上参考。     

浅谈地理信息系统与排水模型软件的结合使用

随着城市排水系统信息化管理要求的提出与实践，城市排水管网地理信息系统和排水管网建模日益受到大家的重视。传统的排水管网建模方法耗时长、建模效率低。排水管网地理信息系统和排水管网模型结合使用的方式可缩短建模周期，提高排水管网建模的科学性，该研究对加快排水管网系统信息化建设有积极作用。     

招标信息

正一、新建污水处理厂工程项目性质:新建项目进展阶段:工程规划建设周期:约1年总投资额:约2亿元资金来源:BOT招商引资相关工程:土建工程、管网工程、厂区工程、景观绿化。相关设备:泵类设备、电气设备、阀门设备。工程概况:该项目为新建污水处理厂工程,建设地点位于四川省,采用BOT模式建设,建设一座污水处理厂及提升泵站,共分两期建设,污水处理厂一期1.96万m3/d,     

镇江市新区第二污水厂水质水量平衡分析研究

本文针对厂外泵站和厂区进水水质水量不一致现象以及污水厂出水NH3-N指标较高的问题,进行了污水厂外泵站和厂区进水水质水量平衡与污水厂内氮平衡的分析研究.根据研究结果,通过改进泵站取样方式,对SS较高的脱水机冲洗水进行沉淀处理以及加强对排水用户的监管后,目前该污水厂运行稳定,水质水量能够保证平衡,出水NH3-N能够稳定达标.     

ECONOMIC DESIGN OF CENTRAL WATER SUPPLY SYSTEMS FOR MEDIUM SIZED TOWNS1

ABSTRACT. Adequate and good-quality water supply for medium sized towns is costly when there are insufficient quantity and low quality of groundwater or surface water. In a central water supply system serving a number of towns, the economies of scale may permit a sufficient and good-quality supply at lesser rates. Such a system has the flexibility of supplying rural population through small service lines. The system may be an interbasin or intrabasin conveyance depending on the location of a suitable water source and the economics of the supply network. Seven cost elements are pertinent to the optimum or least-cost design of network consisting of pipelines and pumping stations. The relevant cost functions are based on the available data gathered from various sources. Water conveyance costs are calculated for various flow rates, pipeline diameters, flow variabilities, static heads, and interest rates, thus providing a measure of sensitivity of the conveyance cost to such variations. The economies of scale, the sensitivity of optimum unit conveyance costs, and variations in unit costs with change in cost functions are useful in making a feasibility study for a proposed conveyance system.     

Optimal design of rainwater collecting systems for domestic use into a residential development

This paper proposes an optimization-based approach for designing rainwater harvesting systems for domestic use in a residential development. The optimization model accounts for the implementation of rainwater harvesting devices, pipes and reservoirs for the optimal sitting, collecting, storing and distribution of harvested rainwater. The optimization model consists in satisfying the water domestic demands and considers as objective function the minimization of the total annual cost associated to the fresh water, the capital costs for the catchment areas, storages and pumps, and the cost associated to the pumping, maintenance and treatment. A case study for a residential development in Morelia, Mexico is presented. The city of Morelia is characterized for having complications to satisfy the water demands, especially during dry seasons. The application of the proposed optimization approach shows that it is possible to satisfy a significant percentage of the domestic water demands using a harvesting rainwater system decreasing the associated cost in the time horizon. Several scenarios have been presented to show the potential solutions identified in the case study.     

可拆卸式橇装增压集成装置在长庆油田中的应用

为了改善长庆油田增压点主要生产设备橇装增压集成装置加热区长时间运行易结垢、维护困难、检修成本高等问题,进行了"可拆卸式橇装增压集成装置"的研制工作。可拆卸式橇装增压集成装置的加热盘管和火筒可直接从装置端部抽出,在加热盘管和火筒遭到腐蚀或结垢破坏后,能够快速进行检修、维护或更换,有效延长了装置整体的使用寿命。"可拆卸式橇装增压集成装置"已在长庆油田得到推广应用。     

RESULTS OF ACIDIZING WATER WELLS IN ARIZONA1

Two wellfields have been developed to provide water for a coal fired electric generating station in Arizona. Wellfield No. 1 penetrates the unconfined Coconino Sandstone aquifer, and wellfield No. 2 penetrates the composite Kaibab Limestone-Coconino Sandstone aquifer where ground water occurs under confined conditions. A well in each wellfield was pumped and water level drawdown data were collected before and after acidizing. The drawdown data at the various pumping rates were analyzed to determine the potential benefits of acidizing production water wells in both wellfields. After acidizing, the specific capacity of the well in wellfield No. 1 was improved about 50 percent at water production rates ranging from about 200 to 500 gallons per minute (gpm) (13 to 32 liters per second (lps)). After acidizing, the specific capacity of the well completed in wellfield No. 2 was improved about 100 percent at pumping rates ranging from about 1,250 to 2,200 gpm (79 to 139 lps). An annual saving of approximately 11 percent in pumping costs can be realized in wellfield No. 2, and savings are approximately four percent in wellfield No. 1. Acidization is beneficial for wells that can produce more than 500 gpm (32 lps), and is of marginal value for those that produce less than that amount.     

A Comparison of Decentralized Minigrids and Dispersed Diesels for Irrigation Pumping in Sahelian Africa

A key ingredient in the expansion of agricultural output in many developing countries is the availability of reliable and cost-effective energy supplies for irrigation. Such supplies are also fundamental to any strategy to stimulate rural economic development. This paper compares the costs of water pumping through the use of commonly-used, small diesel-driven pumpsets versus a decentralized generator connected to a small electrified grid. An example representative of irrigated cropping systems found in the Senegal River Basin is used to compare costs. The results show that pumping costs from a decentralized power supply and minigrid are roughly comparable with those of direct-drive diesel pumpsets. Further, excess capacity would be available to provide power for small industries and other rural needs. In many sparsely populated rural locations where low capacity factors make central grid extension uneconomic, a minigrid with a guaranteed load of irrigation pumping can be an attractive alternative for providing power for rural development.     

CONSOLIDATION OF A STREAM QUALITY MONITORING NETWORK1

ABSTRACT A method for systematic consolidation of a fixed station water quality monitoring network using dynamic programming is described. The approach utilizes a hierarchical structure; stations are allocated to what are termed primary basins on the basis of a weighted attribute score, and specific station locations within each primary basin are specified using a criterion based on stream order numbers. The method has been applied to the Municipality of Metropolitan Seattle (Metro) stream and river quality monitoring network. The results aided in a 1982 metro decision to reduce the scope of its fixed station monitoring from 81 to 47 stations, at an annual savings of approximately $33,000 per year exclusive of equipment depreciation and indirect costs.     

OPTIMIZATION OF INTERMITTENT PUMPING SCHEDULES FOR AQUIFER REMEDIATION USING A GENETIC ALGORITHM1

ABSTRACT: Using a genetic algorithm (GA), optimal intermittent pumping schedules were established to simulate pump‐and‐treat remediation of a contaminated aquifer with known hydraulic limitations and a water miscible contaminant, located within the Duke Forest in Durham, North Carolina. The objectives of the optimization model were to minimize total costs, minimize health risks, and maximize the amount of contaminant removed from the aquifer. Stochastic ground water and contaminant transport models were required to provide estimates of contaminant concentrations at pumping wells. Optimization model simulations defined a tradeoff curve between the pumping cost and the amount of contaminant extracted from the aquifer. For this specific aquifer/miscible contaminant combination, the model simulations indicated that pump‐and‐treat remediation using intermittent pumping schedules for each pumping well produced significant reductions in predicted contaminant concentrations and associated health risks at a reasonable cost, after a remediation time of two years.     

AN ENGINEERING ECONOMIC ANALYSIS OF A PROGRAM FOR ARTIFICIAL GROUNDWATER RECHARGE1

This study describes and demonstrates two alternate methods for evaluating the relative costs and benefits of artificial groundwater recharge using percolation ponds. The first analysis considers the benefits to be the reduction of pumping lifts and land subsidence; the second considers benefits as the alternative costs of a comparable surface delivery system. Example computations are carried out for an existing artificial recharge program in Santa Clara Valley in California. A computer groundwater model is used to estimate both the average long term and the drought period effects of artificial recharge in the study area. For the example problem, the benefits of reduced average annual pumping lifts and reduced incremental subsidence are greater than the total costs of continuing the existing artificial recharge program. Benefits for reduced subsidence are strongly dependent on initial aquifer conditions. The second analysis compares the costs of continuing the artificial recharge program with the costs of a surface system which would achieve the same hydraulic effects. Results indicate that the costs of artificial recharge are considerably smaller than the alternative costs of an equivalent surface system. In evaluating a particular program, consideration should also be given to uncertainties in future supplies and demands for water as well as to the probability of extreme events such as droughts.     

THE OPTIMAL STEADY-STATE IN GROUNDWATER MANAGEMENT1

Groundwater use is likely to be inefficient in the absence of regulation and hence there is substantial interest in optimal groundwater withdrawals over time. Under an optimal regime withdrawals, pumping lifts, and profits converge to steady-state levels. In this paper we show that optimal steady-state lifts, withdrawals, and marginal user costs can be readily calculated for multi-cell models of confined aquifers. Applications to the design of economically efficient groundwater management policies are discussed, comparisons to previous work and to the safe yield concept are made, and an illustrative example is given.