The overall cost, expressed as the present value (PV), of the construction and operation of low-pressure membrane filtration of inland water for potable water supply has been determined for membrane installations across the UK. The analysis was based on 15 full-scale installations installed with hollow fibre and capillary tube polymeric membranes, for which cost and related data were available. The analysis encompassed labour, in addition to energy, chemicals and critical component replacement. PV data were presented as functions of flow capacity (i.e. as cost curves), delineated as capital (CAPEX), operating (OPEX) and total PV normalised against flow rate (PV’) the CAPEX excluding the site-specific civil engineering costs.

Captured CAPEX data revealed these to be lower than those previously reported, and with a reduced economy of scale. The OPEX PV exceeded the CAPEX by a factor of 3-6 based on a 20-year life cycle, the difference increasing with decreasing flow capacities. Costs associated with unplanned (or “reactive”) maintenance, partly associated with the repair of breached membranes and/or permeability recovery following membrane clogging, were found to make up around half the labour costs. Labour costs as a proportion of the flow increased with decreasing flow, exceeding the CAPEX at flows below 30,000 m³/d.

Outcomes indicate labour costs associated with process upsets to contribute significantly to the overall cost of the installation over its life cycle, particularly at flows below ~30,000 m³/d. A clear trade-off exists between supplementary capital investment to allay process upsets and the operational costs associated with such events.

整个英国的膜装置已经确定了用于饮用水的内陆水低压膜过滤的建设和运营的总成本，以现值（PV）表示。该分析是基于15个安装有中空纤维和毛细管聚合物膜的大型装置进行的，可以获得成本和相关数据。除能源，化学药品和关键部件更换外，分析还包括劳动力。PV数据表示为流量的函数（即成本曲线），分别表示为资本（CAPEX），运营（OPEX）和针对CAPEX的流量（PV'）归一化的总PV，不包括特定于现场的土木工程成本。

捕获的CAPEX数据显示，这些数据低于先前报告的数据，并且规模经济有所降低。基于20年的生命周期，OPEX PV比CAPEX高出3-6倍，随着流量的减少，差异增加。发现与计划外（或“反应性”）维护相关的成本，部分与破损膜的修复和/或膜堵塞后的通透性恢复相关，约占人工成本的一半。随着流量的减少，人工成本占流量的比例增加，在流量低于30,000 m ³ / d时超过了资本支出。

结果表明，与过程异常相关的人工成本将极大地影响设备在整个生命周期中的总成本，尤其是在流量低于30,000 m ³ / d的情况下。在缓解过程异常的补充资本投资和与此类事件相关的运营成本之间存在明显的权衡。