Life cycle assessment of nutrient recovery strategies from domestic wastewaters to quantify environmental performance and identification of trade-offs.

Increase in anthropogenic activities proliferated the consumption of resources such as phosphorus; and increase the adverse environmental impacts especially eutrophication on water resources such as lakes. Nutrient recovery from domestic wastewaters to produce a fertiliser has been explored to address these challenges in the context of a sustainable circular nutrient economy. Life cycle assessment (LCA) was performed to holistically assess the impacts of integrating a nutrient recovery system on wastewater and water resource management using Laguna de Bay, Philippines as the geographical boundary.

Machine-learning-aided application of high-gravity technology to enhance ammonia recovery of fresh waste leachate.

Stripping is widely applied for the removal of ammonia from fresh waste leachate. However, the development of air stripping technology is restricted by the requirements for large-scale equipment and long operation periods. This paper describes a high-gravity technology that improves ammonia stripping from actual fresh waste leachate and a machine learning approach that predicts the stripping performance under different operational parameters.

A review of the impact of conductive materials on antibiotic resistance genes during the anaerobic digestion of sewage sludge and animal manure.

The urgent need to reduce the environmental burden of antibiotic resistance genes (ARGs) has become even more apparent as concerted efforts are made globally to tackle the dissemination of antimicrobial resistance. Concerning levels of ARGs abound in sewage sludge and animal manure, and their inadequate attenuation during conventional anaerobic digestion (AD) compromises the safety of the digestate, a nutrient-rich by-product of AD commonly recycled to agricultural land for improvement of soil quality. Exogenous ARGs introduced into the natural environment via the land application of digestate can be transferred from innocuous environmental bacteria to clinically relevant bacteria by horizontal gene transfer (HGT) and may eventually reach humans through food, water, and air.

Transport and deposition of solid phosphorus-based mineral particles in urine diversion systems.

The deposition of solid phosphorus-based mineral particles is a common problem in urine diversion systems, which occurs in transport systems, particularly in horizontal pipelines. In this work, particle deposition behaviour in turbulent flow in a 3D horizontal pipe was simulated by using the Euler-Lagrange method. The effects of particle diameter, particle density, particle shape factor and fluid flow velocity on particle deposition behaviour were investigated.

The role of ozone combined with UVC/HO process for the tertiary treatment of a real slaughterhouse wastewater.

The main goal of this work is to evaluate the usage of ozone (O) as a pre-treatment or simultaneously combined with UVC/HO process for the polishing stage treatment of real bio-treated slaughterhouse wastewater. Two different treatment strategies were tested: i) pre-ozonation of the wastewater followed by an UVC/HO process (two-step treatment); ii) simultaneous application of O/UVC/HO combined process (one-step treatment). For the two-step strategy, the pre-treatment with 30 mg O/min for 10 min reduces significantly total suspended solids (TSS), turbidity and colour, reducing light filtering effects and increasing the efficiency of the following UVC/HO process.

Assessment of the aerobic glass beads fixed biofilm reactor (GBs-FBR) for the treatment of simulated methylene blue wastewater.

The present research is focused on the application of glass beads (GBs) in fixed biofilm reactor (FBR) for the treatment of simulated methylene blue (MB) wastewater for 9 weeks under aerobic conditions. The COD of MB wastewater showed a reduction of 86.48% from 2000 to 270.

Evaluation of aerobic biological process with post-ozonation for treatment of mixed industrial and domestic wastewater for potential reuse in agriculture.

Suspended growth biological process (SGBP) with post-ozonation (O) was investigated for treatment of simulated complex mixed industrial and domestic wastewater at specific conditions. The SGBP was operated under complete aeration, 30/30-min and 60/30-min on/off aeration cycles and effluent was exposed to ozone at 250 mgO/h fixed dose and contact time 1 to 60-min. The SGBP performance was maximum under 60/30-min aeration conditions achieving 92.

Evaluation of tire derived rubber (TDR) fixed biofilm reactor (FBR) for remediation of Methylene blue dye from wastewater.

The present investigation is focused on development of aerobic biofilm on tire-derived rubber (TDR) media and then evaluation of such system for bioremediation of Methylene blue (MB) dye for 9 weeks. After 9 weeks of operation, the COD, BOD, ammonia and color values have been declined by 89.2%, 98.

A Study on removal of Methylene Blue dye by photo catalysis integrated with nanofiltration using statistical and experimental approaches.

In this work, the removal of Methylene Blue dye from the synthetic textile effluent has been investigated using a hybrid system (photocatalysis and nanofiltration). The Commercial ZnO powder was used as a catalyst in the photocatalytic operation. Response surface methodology (RSM) was employed to optimize the various operating parameters such as pH, catalyst loading and time duration and this optimization has enhanced the decolorization efficiencies.

Tertiary treatment of real abattoir wastewater using combined acoustic cavitation and ozonation.

This work reports the influence of ultrasound alone and combined with ozone for the treatment of real abattoir wastewater. Three different frequencies were studied (44, 300 and 1000 kHz) at an applied power of 40 W. The injected ozone dose was fixed at 71 mg/L and the treatment time varied from 1 to 60 min.

Appraisal of Cu(ii) adsorption by graphene oxide and its modelling artificial neural network.

Graphene oxide (GO), as an emerging material, exhibits extraordinary performance in terms of water treatment. Adsorption is a process that is influenced by multiple factors and is difficult to simulate by traditional statistical models. Artificial neural networks (ANNs) can establish highly accurate nonlinear functional relationships between multiple variables; hence, we constructed a three-layered ANN model to predict the removal performance of Cu(ii) metal ions by the prepared GO.

Domestic wastewater treatment efficiency of the pilot-scale trickling biofilter system with variable flow rates and hydraulic retention times.

In this study, a pilot-scale trickling biofilter (TBF) using pebbles and gravels media was evaluated for the treatment of domestic wastewater. The TBF system was installed in an open environment at residential area of Quaid-i-Azam University, Islamabad, Pakistan, and was operated at three different recirculation flow rates (), i.e.

Appraisal of suspended growth process for treatment of mixture of simulated petroleum, textile, domestic, agriculture and pharmaceutical wastewater.

The unrestricted discharge of domestic and industrial wastewaters along with agricultural runoff water into the environment as pose serious threat to freshwater resources in many countries. Mixed-wastewater pollution is a common phenomenon in the developing countries as the technologies to treat the individual waste streams at source are lacking due to high operational and maintenance costs. Therefore, the need to explore the potential of the suspended growth process which is a well-established process technology for biological wastewater treatment is the focus of this paper.

Development and application of novel bio-magnetic membrane capsules for the removal of the cationic dye malachite green in wastewater treatment.

Novel bio-magnetic membrane capsules (BMMCs) were prepared by a simple two-step titration-gel cross-linking method using a polyvinyl alcohol (PVA) and sodium alginate (SA) matrix to control the disintegration of phytogenic magnetic nanoparticles (PMNPs) in an aqueous environment, and their performance was investigated for adsorbing cationic malachite green (MG) dye from water. The prepared BMMCs were characterized by FTIR, powder XRD, SEM, EDX, XPS, VSM and TGA techniques. The findings revealed that the hysteresis loops had an excellent superparamagnetic nature with saturation magnetization values of 11.

Encapsulated green magnetic nanoparticles for the removal of toxic Pb and Cd from water: Development, characterization and application.

Current research is based on an innovative approach of the fabrication of encapsulated sustainable, green, phytogenic magnetic nanoparticles (PMNPs), to inhibit the generation of secondary pollutants (Iron/Fe) during water treatment applications. These novel bio-magnetic membrane capsules (BMMCs) were prepared using two-step titration gel crosslink method, with polyvinyl alcohol and sodium alginate matrix as the model encapsulating materials to eliminate potentially toxic metals (Pb and Cd) from water. The development of BMMCs was characterized by FTIR, XRD, XPS, SEM, VSM, TGA and EDX techniques.

Effect of the chemical composition of filter media on the microbial community in wastewater biofilms at different temperatures.

This study investigates the microbial community composition in the biofilms grown on two different support media in fixed biofilm reactors for aerobic wastewater treatment, using next generation sequencing (NGS) technology. The chemical composition of the new type of support medium (TDR) was found to be quite different from the conventionally used support medium (stone). The analysis of 16S rRNA gene fragments recovered from the laboratory scale biofilm system show that biofilm support media and temperature conditions influence bacterial community structure and composition.

Comparison of phosphorus recovery from incinerated sewage sludge ash (ISSA) and pyrolysed sewage sludge char (PSSC).

This research compares and contrasts the physical and chemical characteristics of incinerator sewage sludge ash (ISSA) and pyrolysis sewage sludge char (PSSC) for the purposes of recovering phosphorus as a P-rich fertiliser. Interest in P recovery from PSSC is likely to increase as pyrolysis is becoming viewed as a more economical method of sewage sludge thermal treatment compared to incineration. The P contents of ISSA and PSSC are 7.

The effect of activated carbon addition on membrane bioreactor processes for wastewater treatment and reclamation - A critical review.

This review concentrates on the effect of activated carbon (AC) addition to membrane bioreactors (MBRs) treating wastewaters. Use of AC-assisted MBRs combines adsorption, biodegradation and membrane filtration. This can lead to advanced removal of recalcitrant pollutants and mitigation of membrane fouling.

Physiological activities associated with biofilm growth in attached and suspended growth bioreactors under aerobic and anaerobic conditions.

This research work evaluated the biofilm succession on stone media and compared the biochemical changes of sludge in attached and suspended biological reactors operated under aerobic and anaerobic conditions. Stones incubated (30±2°C) with activated sludge showed a constant increase in biofilm weight up to the fifth and seventh week time under anaerobic and aerobic conditions, respectively, where after reduction (>80%) the most probable number index of pathogen indicators on ninth week was recorded. Reduction in parameters such as biological oxygen demand (BOD) (47.

Assessment of biological trickling filter systems with various packing materials for improved wastewater treatment.

Attached growth processes for wastewater treatment have significantly been improved during recent years. Their application can be extended to sustainable municipal wastewater treatment in remote locations and in developing countries for the purpose of organic matter (biochemical oxygen demand, BOD) removal and pathogenic decontamination. The aim of this study is to assess selected packing media for biological trickling filters (BTFs) and to develop a simplified model for describing the capacity of BOD removal in BTFs.

Silver-modified clinoptilolite for the removal of Escherichia coli and heavy metals from aqueous solutions.

This paper investigates the potential of using the silver antibacterial properties combined with the metal ion exchange characteristics of silver-modified clinoptilolite to produce a treatment system capable of removing both contaminants from aqueous streams. The results have shown that silver-modified clinoptilolite is capable of completely eliminating Escherichia coli after 30-min contact time demonstrating its effectiveness as a disinfectant. Systems containing both E.

Sub-critical fouling in a membrane bioreactor for municipal wastewater treatment: experimental investigation and mathematical modelling.

Fouling is a major limitation for the application of membrane bioreactors (MBRs) in municipal wastewater treatment; the critical flux concept represents a valid tool for process optimisation in planning fouling control strategies. The paper presents the results obtained on a large pilot MBR equipped with a plate-and-frame ultrafiltration membrane. The experimental assessment of flux criticality was carried out by flux-stepping tests showing the positive impact of liquid temperature on the value of the critical threshold.

Treatment of distillery spent-wash by ozonation and biodegradation: significance of pH reduction and inorganic carbon removal before ozonation.

This study is aimed at exploring strategies for mineralization of refractory compounds in distillery effluent by anaerobic biodegradation/ozonation/aerobic biodegradation. Treatment of distillery spent-wash used in this research by anaerobic-aerobic biodegradation resulted in overall COD removal of 70.8%.

Mineralization of some natural refractory organic compounds by biodegradation and ozonation.

The objective of this study was to explore the extent of mineralization, reduction in color and reduction of COD of gallic acid, tannin and lignin by ozonation and a combination of aerobic biodegradation and ozonation. Ozonation of pure aliquots (phase I experiments) resulted in the decline in TOC, COD, COD/TOC ratio, UV absorbance at 280 nm and color of the three model compounds investigated, with COD removals of greater than 80% and high removals (>90%) of UV absorbance at 280 nm and color observed in all cases at an ozone dose of 6 mg ozone/mg initial TOC or higher. Aerobic biodegradation of pure gallic acid, tannin and lignin aliquots resulted in COD decline of approximately 36-38%.