Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ, Delft, The Netherlands.
Department of Environmental Engineering and Water Technology, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX, Delft, The Netherlands.
Environ Sci Pollut Res Int. 2022 Jun;29(28):42016-42036. doi: 10.1007/s11356-021-17018-z. Epub 2021 Oct 31.
The provision of effective sanitation strategies has a significant impact on public health. However, the treatment of septic sludge still presents some challenges worldwide. Consequently, innovative technologies capable of an effective and efficient sludge treatment, mostly at a decentralized level, are in high demand to improve sanitation provision. To address this problem, this study evaluates a novel semi-decentralised mobile faecal sludge treatment system, the pilot-system for which consists of a combination of several individual processes including mechanical dewatering (MD), microwave (MW) drying, and membrane filtration (ultrafiltration [UF] and reverse osmosis [RO]). The system evaluation was carried out by treating raw, partially digested faecal sludge (FS) from septic tanks-hence, septic sludge (SS)-in the Jordan Valley, Jordan. The pilot-scale system exhibited an effective and flexible treatment performance for (i) sanitizing faecal sludge and related liquid streams (MW and UF); (ii) reducing the treated sludge mass (and sludge volume) (MD and MW); and (iii) producing a high-quality treated liquid stream ideal for water reclamation applications (UF and RO). The MD process removed approximately 99% of the initial SS water content. The MW drying system completely removed E. coli and dehydrated the dewatered sludge at low energy expenditures of 0.75 MJ kg and 5.5 MJ kg, respectively. Such energy expenditures can be further reduced by approximately 40% by recovering energy in the condensate and burning the dried sludge, which can then be reused inland applications. The membrane filtration system (UF and RO) was able to produce high-quality treated water that is ideal for the water reuse applications that irrigation requires, as well as meeting the Jordanian standard 893/2006. In addition, the system can also be powered by renewable energy sources, such as photovoltaic energy. Therefore, this research demonstrates that the evaluated semi-decentralised mobile system is technically feasible for the in situ treatment of SS (sanitization and dehydration), while also being effective for simultaneously recovering valuable resources, such as energy, water, and nutrients.
有效的卫生策略的提供对公共卫生有重大影响。然而，全球范围内，处理污水污泥仍然存在一些挑战。因此，需要创新技术来有效地处理污泥，尤其是在分散化水平上，以改善卫生设施的提供。为了解决这个问题，本研究评估了一种新颖的半分散式移动粪便污泥处理系统，该系统的中试系统由包括机械脱水（MD）、微波（MW）干燥和膜过滤（超滤[UF]和反渗透[RO]）在内的几个单独工艺的组合组成。该系统评估是通过在约旦河谷处理来自化粪池的原始、部分消化的粪便污泥（FS），即污水污泥（SS）来进行的。该中试系统对（i）粪便污泥和相关液体流（MW 和 UF）的消毒；（ii）减少处理后的污泥质量（和污泥体积）（MD 和 MW）；（iii）生产适合水回收应用的高质量处理后的液体流（UF 和 RO）表现出有效的、灵活的处理性能。MD 工艺去除了初始 SS 水分含量的约 99%。MW 干燥系统完全去除了大肠杆菌，并以低能量消耗（分别为 0.75 MJ kg 和 5.5 MJ kg）将脱水后的污泥脱水。通过在冷凝物中回收能量并燃烧干燥的污泥，可将能量消耗分别进一步降低约 40%，然后可将其在国内应用中再利用。膜过滤系统（UF 和 RO）能够生产出高质量的处理水，非常适合灌溉所需的水再利用应用，同时也符合约旦标准 893/2006。此外，该系统还可以由可再生能源（如光伏能源）供电。因此，本研究表明，所评估的半分散式移动系统在原位处理 SS（消毒和脱水）方面具有技术可行性，同时还可以有效地同时回收有价值的资源，如能源、水和营养物质。
