Microalgae - bacteria based wastewater treatment systems: Granulation, influence factors and pollutants removal.

Wastewater treatment based on microalgae and bacteria symbiosis is an environmentally friendly, sustainable technology that has attracted attention recently because of its high efficiency in treating pollutants, saving energy, and short-term biomass recovery. Among them, the granular microalgae and bacteria combination emerges with the advantages of rapid gravity settling, good resistance to adverse environmental conditions, outstanding wastewater treatment performance, and easy biomass recovery. This review aims to clarify the microalgal-bacterial granule (MBG) - based process for wastewater treatment.

Microplastics in wastewater and sludge from centralized and decentralized wastewater treatment plants: Effects of treatment systems and microplastic characteristics.

Domestic wastewater treatment plants (WWTPs) play a vital role in limiting the release of microplastics (MP) into the environment. This study examined MP removal efficiency from five centralized and four decentralized domestic WWTPs in Bangkok, Thailand. MP concentrations in wastewater and sludge were comparable between centralized and decentralized WWTPs, despite these decentralized WWTPs serving smaller populations and having limited treatment capacity.

Bacterial community composition in a two-stage anaerobic membrane bioreactor for co-digestion of food waste and food court wastewater.

This study investigated the microbial community of a two-stage anaerobic membrane bioreactor (2S-AnMBR) co-digesting food waste and food court wastewater. The hydrolysis reactor (HR) was dominated by Bacteroidetes and Firmicutes phylum, with genus Lactobacillus enriched due to food waste fermentation. The up-flow anaerobic sludge blanket (UASB) was dominated by genus such as Methanobacterium and Methanosaeta.

Cleaner production auditing for plastic recycling industry in Pakistan: A baseline study.

Recycling plastics is a good alternative to manage the plastic waste generated in Pakistan. Unfortunately, the country lacks efficient system to manage or recycle the plastic waste it generates. Lack of government support, absence of standard operating procedures, negligence towards health and safety of workers, increasing costs of raw materials and poor quality of the recyclates are some of the issues currently faced by plastic recyclers in Pakistan.

Removal of gas phase methanol and acetonitrile mixture in an air membrane bioreactor (aMBR) under steady and transient-state operations.

A laboratory scale air membrane bioreactor (aMBR) was used to treat a gas-phase mixture of methanol (MeOH) and acetonitrile (ACN), with an inoculum comprising of a mixed culture of microorganisms. The aMBR was tested under both steady-state and transient modes, with inlet concentrations ranging from 1 to 50 g/m for both compounds. Under steady-state conditions, the aMBR was operated at various empty bed residence times (EBRT) and MeOH:ACN ratios, while intermittent shutdown was tested during transient-state operations.

Performance of pilot-scale membrane aerated biofilm reactors integrated with anoxic nano-biotechnological reactor for domestic wastewater treatment.

Membrane-aerated biofilm reactors (MABRs) have aroused increasing attention due to their excellent performance in treating wastewater, where the membranes behave as bio-carriers for microorganisms and bubbleless air diffusers. The MABR technology has not been fully commercialized due to reactor design and low total nitrogen (TN) removal efficiency at short hydraulic retention times (HRT). In this study, a hybrid system of MABR 1 integrated with an anoxic nano-biotechnological reactor filled with Granulated Nanoscale Oxyhydroxides of Fe (GNOF) media was evaluated to assess the improvement in nitrogen removal performance at 12, 10, and 4 h of HRTs.

Effects of membrane relaxation rate on performance of pilot-scale membrane aerated biofilm reactors treating domestic wastewater.

The membranes of a Membrane Aerated Biofilm Reactor (MABR) function as bubble-less air diffusers and bio-carriers. Recent bench-scale experiments reported that the shape of membranes influenced the oxygen transfer and utilization rates, which in turn affected the pollutant removal performance of the MABR. In this study, two pilot-scale MABRs using multi-layer hollow fiber membranes with the relaxation rates of 0.

Non-submerged attached growth process for domestic wastewater treatment: Influence of media types and internal recirculation ratios.

This study is aimed to comprehend the treatment of non-submerged attached growth systems using bio-sponge, bio-cord, and bio-cloth media. Three reactors were set up with internal recirculation ratio of 1 (IR = 1) and similar media surface area. Bio-sponge and bio-cloth reactors showed removal of COD (79 vs.

Applications of Membranes for Sustainability.

Applications of membranes in water and wastewater treatment, desalination, as well as other purification processes, have become more widespread over the past few decades [...

Assessment of urban solid waste management systems for Industry 4.0 technology interventions and the circular economy.

The ongoing fourth industrial revolution, Industry 4.0 (I4.0), is transforming various industries across the globe.

Electroconductive moving bed membrane bioreactor (EcMB-MBR) for single-step decentralized wastewater treatment: Performance, mechanisms, and cost.

Membrane bioreactor (MBR) is an advantageous technology for wastewater treatment. However, efficient nutrient removal and membrane fouling mitigation remain major challenges in its applications. In this study, an electroconductive moving bed membrane bioreactor (EcMB-MBR) was proposed for simultaneous removal of organics and nutrients from domestic wastewater.

Performance of an air membrane bioreactor for methanol removal under steady and transient state conditions.

The main aim of this study was to evaluate the performance of an air membrane bioreactor (aMBR) for the treatment of gas-phase methanol. A laboratory-scale hollow fiber aMBR was operated for 150 days, at inlet methanol concentrations varying between 2 and 30 g m and at empty bed residence times (EBRT) of 30, 10 and 5 s. Under steady-state conditions, a maximum methanol removal efficiency (RE) of 98% was obtained at an EBRT of 30 s and a decrease in RE of methanol was observed at lower EBRTs.

Sustainable management practices of food waste in Asia: Technological and policy drivers.

The policies and technological drivers to manage food waste in Asia have been shaped by the increasing awareness of the countries to this issue, their commitment to national and international development goals, their socio-economic constraints, and their recognition of the potency to recover nutrients and energy from food waste. The concept of reduce, reuse and recycle (the 3R principles) streamline the existing food waste management policies, and scrutinising the gaps and challenges led to a conclusion that most of the countries emphasise food waste segregation and treatment instead of prevention at source itself. Furthermore, a qualitative SWOT analysis of five prevailing treatment options led to a conclusion that animal feeding, incineration, and landfilling are unsustainable since they pose various health and environmental hazard risks.

Performance Evaluation of a Thermophilic Anaerobic Membrane Bioreactor for Palm Oil Wastewater Treatment.

Anaerobic treatment processes have achieved popularity in treating palm oil mill effluent due to its high treatability and biogas generation. The use of externally submerged membranes with anaerobic reactors promotes the retention of the biomass in the reactor. This study was conducted in thermophilic conditions with the Polytetrafluoroethylene hollow fiber (PTFE-HF) membrane which was operated at 55 °C.

Management strategies for anaerobic digestate of organic fraction of municipal solid waste: Current status and future prospects.

Anaerobic digestion has emerged as the preferred treatment for organic fraction of municipal solid waste. Digestate management strategies are devised not only for safe disposal but also to increase the value and marketability. Regulations and standards for digestate management are framed to address the pollution concerns, conserve vulnerable zones, prevent communicable diseases, and to educate on digestate storage and applications.

Effect of thermal pretreatment on chemical composition, physical structure and biogas production kinetics of wheat straw.

Hard lignocellulosic structure of wheat straw is the main hindrance in its anaerobic digestion. Thus, a laboratory scale batch experiment was conducted to study the effect of thermal pretreatment on anaerobic digestion of wheat straw. For this purpose, different thermal pretreatment temperatures of 120, 140, 160 and 180 °C were studied and the results were compared with raw wheat straw.

Evaluation of virus removal efficiency of coagulation-sedimentation and rapid sand filtration processes in a drinking water treatment plant in Bangkok, Thailand.

In order to properly assess and manage the risk of infection by enteric viruses in tap water, virus removal efficiency should be evaluated quantitatively for individual processes in actual drinking water treatment plants (DWTPs); however, there have been only a few studies due to technical difficulties in quantifying low virus concentration in water samples. In this study, the removal efficiency of indigenous viruses was evaluated for coagulation-sedimentation (CS) and rapid sand filtration (RSF) processes in a DWTP in Bangkok, Thailand by measuring the concentration of viruses before and after treatment processes using real-time polymerase chain reaction (qPCR). Water samples were collected and concentrated from raw source water, after CS, and after RSF, and inhibitory substances in water samples were reduced by use of a hydrophobic resin (DAX-8).

Effect of mixing ratio of food waste and rice husk co-digestion and substrate to inoculum ratio on biogas production.

Aim of this study was to find out suitable mixing ratio of food waste and rice husk for their co-digestion in order to overcome VFA accumulation in digestion of food waste alone. Four mixing ratios of food waste and rice husk with C/N ratios of 20, 25, 30 and 35 were subjected to a lab scale anaerobic batch experiment under mesophilic conditions. Highest specific biogas yield of 584L/kgVS was obtained from feedstock with C/N ratio of 20.

Dealing with emerging waste streams: used tyre assessment in Thailand using material flow analysis.

Increasing urbanisation and automobile use have given rise to an increase in global tyre waste generation. A tyre becomes waste once it wears out and is no longer fit for its original purpose, and is thus in its end-of-life state. Unlike in developed countries, where waste tyre management has already become a significant issue, it is rarely a priority waste stream in developing countries.

Effect of polyvinyl alcohol hydrogel as a biocarrier on volatile fatty acids production of a two-stage thermophilic anaerobic membrane bioreactor.

This work studied the effect of polyvinyl alcohol hydrogel (PVA-gel) beads, as an effective biocarrier for volatile fatty acid (VFA) production in hydrolytic reactor of a two-stage thermophilic anaerobic membrane bioreactor (TAnMBR). The two-stage TAnMBR, treating synthetic high strength particulate wastewater with influent chemical oxygen demand (COD) [16.4±0.

Using social network and stakeholder analysis to help evaluate infectious waste management: a step towards a holistic assessment.

Assessing the strengths and weaknesses of a solid waste management scheme requires an accurate analysis and integration of several determining features. In addition to the technical aspects, any such system shows a complex interaction of actors with varying stakes, decision-making power and influence, as well as a favourable or disabling environment. When capitalizing on the knowledge and experience from a specific case, it is also crucial that experts do not "forget" or underestimate the importance of such social determinants and that they are familiar with the methods and tools to assess them.

Low flux submerged membrane bioreactor treating high strength leachate from a solid waste transfer station.

A submerged membrane bioreactor was employed to treat high strength leachate generating from a solid waste transfer station. The reactor was operated at low fluxes of 1.2; 2.