A pilot plant experiment was carried out to assess differences in environmental conditions and treatment performance in two systems for wastewater treatment: algae-based ponds (ABP) and duckweed-based (Lemna gibba) ponds (DBP). Each system consisted of a sequence of 4 equal ponds in series and was fed with a constant flow rate of partially treated wastewater from Birzeit University. Physico-chemical parameters and the removal of organic matter, nutrients and faecal coliforms were monitored within each treatment system over a period of 12 months. The results show clear differences in the environmental conditions. In ABP significantly (P>0.05) higher pH and DO values were observed than in DBP. DBP were more efficient in removal of organic matter (BOD and TSS) than ABP. The faecal coliform reduction was higher in ABP. However, the quality of the effluent from the third and fourth duckweed pond (total retention time of 21 and 28 days) did not exceed the WHO-criteria for unrestricted irrigation during both the summer and winter period, respectively. During the summer period, the average total nitrogen was reduced more in ABP (80%) than in DBP (55%). Lower values were measured during the winter period. Seasonal nitrogen reductions of the two systems were significantly different (P>0.05). In DBP, 33% and 15% of the total nitrogen was recovered into plant biomass and removed from the system via duckweed harvesting during the summer and winter period, respectively. This study showed that there were differences in the environmental conditions and treatment efficiencies between the two systems.

Reuse of treated effluent is a highly valued water source in Palestine, however with limited success due to public health concerns. This paper assesses the potential pathogens in raw, treated and reclaimed wastewater at Albireh urban wastewater treatment facility, and provides scientific knowledge to update the Palestinian reuse guidelines. Laboratory analyses of collected samples over a period of 4 months have indicated that the raw wastewater from Albireh city contained high numbers of fecal coliforms and worm eggs while 31% of the samples were Salmonella positive. Treated effluent suitable for restricted irrigation demonstrated that the plant was efficient in removing indicator bacteria, where fecal coliforms and fecal streptococci removal averaged 99.64% and 93.44%, respectively. Although not disinfected, treated effluent was free of Salmonella and parasites, hence safe for restricted agricultural purposes. All samples of the reclaimed effluent and three samples of irrigated grass were devoid of microbial pathogens indicating a safe use in unrestricted agricultural utilization. Adequate operation of wastewater treatment facilities, scientific updating of reuse guidelines and launching public awareness campaigns are core factors for successful and sustainable large-scale wastewater reuse schemes in Palestine.

Purpose – This paper seeks to evaluate the present onsite sanitation systems in Palestinian rural areas in Ramallah-Albireh district with special emphasis on technical, socio-cultural and financial aspects. Design/methodology/approach – A specialized questionnaire was developed and distributed to 200 households in four randomly selected villages with less than 5,000 persons and having onsite sanitation facilities. WAWTTAR software package was used to evaluate 16 different treatment systems and to select a sustainable onsite treatment system for these rural areas based on technical, environmental, financial and socio-cultural considerations. Findings – Major findings indicated that most of the respondents were in favor of using treated grey wastewater and equally rejected the use of mixed treated effluent for agricultural irrigation. More than 50 percent of the respondents were against having new onsite treatment systems and favored centralized wastewater treatment options, as only 18 percent showed willingness to participate partially in construction costs. The WAWTTAR data analysis on feasible onsite treatment alternatives revealed that the septic tank-subsurface wetland system offers a higher level of sustainability to rural communities in Ramallah-Albireh district. Finally, the social and economical aspects have an equal status in technical and financial issues. Practical implications – The results obtained can be utilized by local and international experts seeking a carrier in the planning and design of sustainable sanitation facilities in developing countries or for those who have newly filled a post in governmental, non-governmental or academic institutions. Originality/value – This paper highlights adequate tools for the selection of sustainable onsite sanitation systems in Palestinian rural communities. Methodology and dissemination of the obtained results can be applied to other rural communities in developing countries.

A pilot-scale (0.5 m³) anaerobic digester was constructed in a small Palestinian poultry farm. The farm, located in Beit Ur Al Foqa village of Ramallah district, with a total area of 140 m² and accommodating about 1800 birds every 50 days produces annually about 6.57 tonnes (18 kg/day). The digester was filled with poultry manure and operated to obtain design parameters for a farm-scale biogas plant. The digester contained 20% of poultry manure co-digested with seed materials (70% cow manure and 10% anaerobic sludge) and mixed with the water in (1:1 ratio) to create dry digestion conditions (20% TS). Operated for one year, the feeding sequence of the anaerobic digester was once a day with a loading capacity of the daily produced manure in the farm. A low-cost solar water heating system was installed to enhance the biogas production in the digester under mesophilic process conditions. Poultry manure proved a suitable substrate for the installed biogas digester with total solids: 20%, and C:N ratio: 32:1. Total biogas production was 39.95 m³, and the methane content ranged between 46% and 68%. As substitute to natural gas, the biogas generated (788 MJ) was used for farm heating purposes during the study period. The fresh anaerobically digested slurry showed a nutrient rich fertilizer (NPK ratio of 2:3:3). Sun-drying of digested slurry increased pathogens removal (F. streptococcus) up to 3 log₁₀. Anaerobic digestion of poultry manure constitutes a bio-resource for both energy and nutrients. It is therefore an environmentally sound technology with zero waste emissions.