Saltonstall湖水处理厂（LSWTP）由康涅狄格州纽黑文地区水资源管理局（Authority）拥有和运营，是一个每天1200万加仑（mgd）的常规处理厂。LSWTP包括快速投加、絮凝、沉淀、过滤和氯消毒。目前，LSWTP符合所有现有法规。然而，据确定，LSWTP将难以满足有关消毒副产品形成、隐孢子虫失活或清除增加的预期法规，并且难以继续满足客户对控制味道和气味化合物的期望。对可用的水处理工艺进行了审查，以确定这些工艺的适当组合，以满足水质目标。治疗方案包括高剂量的药物组合- 速率沉淀、过滤、替代消毒、微滤、超滤和纳滤过程。根据其满足水质目标的能力对处理序列进行评估和评级。对获得最高评级的五个治疗序列进行了成本分析。然后计算这些列车的效益成本比。研究发现，使用臭氧和生物活性炭（BAC）过滤器的效益成本比最高。臭氧是一种强力消毒剂，具有灭活隐孢子虫的能力。臭氧和BAC过滤器的组合也被用于DBP去除、味道和气味控制。然而，由于工厂的布局，对现有设施进行改造以适应这些工艺将是困难的。此外，新的研究表明，臭氧在低温下对隐孢子虫的灭活没有那么有效。 冬季条件需要更长的接触时间和臭氧剂量。因此，这个过程可能不像最初的想法那样具有成本效益。次高效益成本比的处理系列包括浸没式超滤（UF）和混凝剂以及粉末活性炭（PAC）。与噻酮/BAC工艺相比，浸入式超滤系统有几个优点。然而，有了这种治疗方案，许多优势仍然是未经证实的假设。因此，设计了一个中试测试程序来回答以下问题:在这种反应器模式下，能否使用混凝剂和PAC来提供足够的DBP前体去除，以满足预期的DBP要求；PAC能否在反应器模式下用于处理与藻类有关的味道和气味；使用混凝剂和PAC会对通量、固体废物率、膜性能和清洗频率产生什么影响； 而且，这种一体式膜方法真的是解决这些问题的一种经济有效的解决方案吗。包括数字。

The Lake Saltonstall Water Treatment Plant (LSWTP), owned and operated by theRegional Water Authority (Authority) in New Haven, Connecticut, is a 12-milliongallons per day (mgd) conventional treatment plant. The LSWTP consists of rapidmixing, flocculation, sedimentation, filtration, and disinfection with chlorine.Currently, the LSWTP meets all existing regulations. However, it was determinedthat the LSWTP would have difficulty meeting anticipated regulations regardingdisinfection byproduct formation, increased Cryptosporidium inactivation orremoval, and difficulty continuing to meet customers' expectations regarding thecontrol of taste and odor-causing compounds. A review of the available watertreatment processes was performed to determine the appropriate combinations ofthese processes to meet the water quality goals. The treatment trains consistedof combinations of high-rate sedimentation, filtration, alternative disinfection,microfiltration, ultrafiltration, and nanofiltration processes. The treatmenttrains were evaluated and rated based on their ability to meet water-qualitygoals. A cost analysis was performed for the five treatment trains that receivedthe highest ratings. A benefit-to-cost ratio was then calculated for thesetrains. The use of ozone followed by biologically activated carbon (BAC) filterswas found to have the highest benefit-to-cost ratio. Ozone is a powerfuldisinfectant that has the ability to inactivate Cryptosporidium. The combinationof ozone and BAC filters has also been used for DBP removal and taste and odorcontrol. However, retrofits to the existing facility to accommodate theseprocesses would be difficult because of the plant's layout. Additionally, newstudies show that ozone is not as effective at inactivating Cryptosporidium atlow temperatures. Winter conditions require much higher contact times and ozonedosage. Therefore, this process may not be as cost effective as originallythought. The treatment train with the next highest benefit-to-cost ratioconsisted of immersed ultrafiltration (UF) with coagulant and powdered activatedcarbon (PAC) addition. An immersed UF system has several advantages over theozone/BAC process. However, with this treatment train, many of the advantageswere still unproven hypotheses. Therefore, a pilot-testing program was designedto answer the following questions: can coagulant and PAC be used in this reactormode to provide sufficient DBP precursor removal to meet anticipated DBPrequirements; can PAC be used in a reactor mode to address taste and odorsrelated to algae; what impacts will using coagulant and PAC have on the fluxrate, solids waste rate, membrane performance, and cleaning frequency; and, isthis all-in-one membrane approach really a cost-effective solution for addressingthese issues. Includes figures.