ABSTRACT
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-1 and 5.5 MJ kg-1, 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.
Subject(s)
Escherichia coli , Sewage , Dehydration , Humans , Jordan , Waste Disposal, Fluid , WaterABSTRACT
Titanium dioxide thin films immobilized over treated stainless steel were prepared using the pulsed electrophoretic deposition technique. The effects of process parameters (deposition time, applied voltage, initial concentration, and duty cycle) on photocatalytic efficiency and adhesion properties were investigated. To optimize the multiple properties of the thin film, a response surface methodology was combined with a desirability optimization methodology. Additionally, a quadratic model was established based on response surface analysis. The precision of the models was defined based on the analysis of variance (ANOVA), R2, and the normal plot of residuals. Then, a desirability function was used to optimize the multiple responses of the TiO2 thin film. The optimum values of applied voltage, catalyst concentration, duty cycle, and deposition time were 4 V, 16.34 g/L, 90% DC, and 150 s, respectively. Under these conditions, the decolorization efficiency of tested dye solution reached 82.75%. The values of critical charges LC1, LC2, and LC3 were 5.9 N, 12.5 N, and 16.7 N, respectively.
ABSTRACT
Renewable energy penetration in the national electrical grid in Jordan has been rapidly increasing in the last few years, touching nearly 30%. Limited grid capacity has been a driver to slow down large-scale projects and has motivated increased attention towards off-grid photovoltaic (PV) systems. Planning properly-sized on-grid and off-grid systems requires accurate knowledge of the environmental and irradiance conditions at the installation site. As off-grid systems are equally of interest to non-critical types of loads, investments are directed towards agricultural applications like water pumping and desalination. To assess the potential of expanding the renewable energy penetration in agricultural areas in the Jordan valley and surrounding areas, this article presents annually measured environmental data including irradiance, temperature and wind speed, in addition to data related to soling on an existing off-grid PV system installed in the Jordan Valley. These data are used in the research article entitled "Performance Analysis of Off-grid PV systems in the Jordan Valley", Al-Addous et al., 2017, and in the research article entitled "Modelling and Quantifying of Dust Accumulation Impact on PV Module Performance" Al-Addous et al., 2019. Data were collected and gathered using calibrated, high accuracy sensors installed at different parts of the installed plant.
