Groundwater implications on methane emission from non-sewered sanitation systems in Nepal.

Non-sewered sanitation systems (NSSS) are identified as significant contributors of greenhouse gases (GHGs), primarily due to biological processes occurring within the containment systems. In unsealed or unlined containment systems like pit latrines, the emissions are influenced by moisture. This work quantified the GHG emission from unlined or unsealed containments prevalent in Nepal and compared it with sealed containment-like septic tanks, where the chances of groundwater (GW) inundation are low.

Field-based methods for measuring greenhouse gases emissions from on-site sanitation systems: A systematic review of published literature.

On-site sanitation systems (OSS) are a source of greenhouse gas (GHG) emissions. Although efforts have been made recently to measure and quantify emissions from septic tanks using various field-based methods, the vast majority of published literature reporting GHG emissions from OSS units (e.g.

Algae-based treatment of a landfill leachate pretreated by coagulation-flocculation.

Landfill leachate (LL) management is an urgent issue at recently closed Sisdol Landfill Site (SLS) used to dispose of solid waste generated in Kathmandu (Nepal) as untreated leachate is flowing directly to the nearby Kolpu River causing environmental and health concerns. This study aims to assess the potential of algae-based treatment of LL pretreated by optimized coagulation-flocculation (CF) for the removal of conventional pollutants such as biological oxygen demand (BOD), chemical oxygen demand (COD), ammonia, nitrate, and phosphate. Response Surface Methodology (RSM) was used to optimize the operating variables (dose and pH) during the pretreatment of leachate by the CF process using ferric chloride (FeCl.

Biohythane production from food waste in a two-stage process: assessing the energy recovery potential.

Biohythane (hydrogen + methane) production in a two stage dark fermentation (DF) and anaerobic digestion (AD) process from food waste (FW) has been studied. This paper investigated the effect of operation temperature, i.e.

Purple phototrophic bacteria for resource recovery: Challenges and opportunities.

Sustainable development is driving a rapid focus shift in the wastewater and organic waste treatment sectors, from a "removal and disposal" approach towards the recovery and reuse of water, energy and materials (e.g. carbon or nutrients).

Enhanced micropollutant biodegradation and assessment of nitrous oxide concentration reduction in wastewater treated by acclimatized sludge bioaugmentation.

This research investigated the micropollutant biodegradation and nitrous oxide (NO) concentration reduction in high strength wastewater treated by two-stage activated sludge (AS) systems with (bioaugmented) and without (non-bioaugmented) acclimatized sludge bioaugmentation. The bioaugmented and non-bioaugmented systems were operated in parallel for 228 days, with three levels of concentrations of organics, nitrogen, and micropollutants in the influent: conditions 1 (low), 2 (moderate), and 3 (high). The results showed that, under condition 1, both systems efficiently removed the organic and nitrogen compounds.

Effect of total solids content on biohydrogen production and lactic acid accumulation during dark fermentation of organic waste biomass.

Production of biohydrogen and related metabolic by-products was investigated in Solid State Dark Fermentation (SSDF) of food waste (FW) and wheat straw (WS). The effect of the total solids (TS) content and H partial pressure (pp), two of the main operating factors of SSDF, were investigated. Batch tests with FW at 10, 15, 20, 25 and 30% TS showed considerable effects of the TS on metabolites distribution.

Bio-hythane production from microalgae biomass: Key challenges and potential opportunities for algal bio-refineries.

The interest in microalgae for wastewater treatment and liquid bio-fuels production (i.e. biodiesel and bioethanol) is steadily increasing due to the energy demand of the ultra-modern technological world.

Photofermentative production of hydrogen and poly-β-hydroxybutyrate from dark fermentation products.

The aim of this work is to investigate the hydrogen and poly-β-hydroxybutyrate (PHB) production during the photofermentative treatment of the effluent from a dark fermentation reactor fed with the organic fraction of municipal solid waste. Two different inocula, an adapted culture of Rhodobacter sphaeroides AV1b and a mixed consortium of purple non sulphur bacteria have been investigated under the same operational conditions. Different hydrogen productivities of 364 and 559NmL H L were observed for the Rhodobacter sphaeroides and the mixed culture consortium tests, respectively: the consortium of PNSB resulted 1.

Recent insights into the cell immobilization technology applied for dark fermentative hydrogen production.

The contribution and insights of the immobilization technology in the recent years with regards to the generation of (bio)hydrogen via dark fermentation have been reviewed. The types of immobilization practices, such as entrapment, encapsulation and adsorption, are discussed. Materials and carriers used for cell immobilization are also comprehensively surveyed.

Concomitant biohydrogen and poly-β-hydroxybutyrate production from dark fermentation effluents by adapted Rhodobacter sphaeroides and mixed photofermentative cultures.

This work aimed at investigating concomitant production of biohydrogen and poly-β-hydroxybutyrate (PHB) by photofermentation (PF) using dark fermentation effluents (DFE). An adapted culture of Rhodobacter sphaeroides AV1b (pH 6.5, 24±2°C) achieved H2 and PHB yields of 256 (±2) NmLH2/g Chemical Oxygen Demand (COD) and 273.

Effects of operational parameters on dark fermentative hydrogen production from biodegradable complex waste biomass.

This work aimed to investigate the effect of the initial pH, combination of food to microorganism ratio (F/M) and initial pH, substrate pre-treatment and different inoculum sources on the dark fermentative biohydrogen (H2) yields. Three model complex waste biomasses (food waste, olive mill wastewater (OMWW) and rice straw) were used to assess the effect of the aforementioned parameters. The effect of the initial pH between 4.

Dark fermentation of complex waste biomass for biohydrogen production by pretreated thermophilic anaerobic digestate.

The Biohydrogen Potential (BHP) of six different types of waste biomass typical for the Campania Region (Italy) was investigated. Anaerobic sludge pre-treated with the specific methanogenic inhibitor sodium 2-bromoethanesulfonic acid (BESA) was used as seed inoculum. The BESA pre-treatment yielded the highest BHP in BHP tests carried out with pre-treated anaerobic sludge using potato and pumpkin waste as the substrates, in comparison with aeration or heat shock pre-treatment.