阿拉米达县水区（ACWD）从多个水源取水，以满足 客户需求，包括通过反渗透（RO）淡化含盐地下水 治疗与CDM一起，ACWD刚刚完成了对 微咸水反渗透海水淡化设施的容量翻了一番，达到12.5 mgd。 该设施处理微咸水，回收率高达80%。治疗 设施包括筒式过滤器、反渗透给水的化学调节， 通过低压反渗透脱盐，空气汽提去除二氧化碳（脱碳）， 以及其他化学后处理。现有反渗透工艺包括两种反渗透工艺 列车，每列42:21排列。设施扩建设计阶段考虑了几个因素，包括: 锰污染，现有膜的经验，包括 改善给水水质TDS、净化水水质目标、降低给水酸 使用和反渗透给水泵选择，以涵盖可变的反渗透回收率和给水 TDS。该设计还融入了其他所需功能，包括能量回收 涡轮机，集中泵送，对四个歧管RO的给水加压 撬块、V型端口球阀和截止阀，以将噪音和气穴降至最低，以及 允许脱碳器定期氯化的规定，以尽量减少生物生长。包括表格、数字。

The Alameda County Water District (ACWD) draws from multiple water sources to meet customer demands, including desalinating brackish groundwater by reverse osmosis (RO) treatment. Together with CDM, ACWD just completed design of an expansion to Brackish Groundwater RO Desalination Facility that doubled the capacity to 12.5 mgd. The facility treats brackish groundwater with recovery rates of up to 80%. The treatment facility includes cartridge filters, chemical conditioning of the RO feed water, desalination by low pressure RO, air stripping to remove carbon dioxide (decarbonation), and miscellaneous chemical post treatment. The existing RO process includes two RO trains, each with 42:21 arrays. Several factors were considered during the facility expansion design phase, including: manganese fouling, experience with the existing membranes including operation with improving feed water quality TDS, treated water quality goals, reduced feed water acid use, and RO feed pump selection to cover variable RO recovery rates and feed water TDS. The design also incorporated other desired features including energy recovery turbines, centralized pumping to pressurize the feed water to the four manifolded RO skids, V-port ball valves and globe valves to minimize noise and cavitation, and provisions to allow the periodic chlorination of the decarbonators to minimize biogrowth. Includes tables, figures.