48 research outputs found
Implications of short and long term critical flux experiments for laboratory-scale MBR operations
No full textThis paper evaluates the critical flux obtained by different techniques including tests with different flux step lengths (20 and 40 min and 7 days) and modes of operation (continuous and intermittent) under low and high MLSS concentrations. The paper also analyses a couple of long-term tests (flow rate of 40 and 20 L/day) to obtain the time required to reach the critical flux experimentally and compares those values with the results obtained numerically from a mathematical model. It was found that intermittent mode with membrane relaxation was useful in controlling the fouling of membrane and in restoring the membrane from fouling at lower MLSS
Review on Sustainable Construction and Demolition Waste Management—Challenges and Research Prospects
No full text(1) Background: Globally, numerous development projects are being undertaken to expand and improve urban infrastructure facilities, which result in around 30% to 40% of construction and demolition (C&D) waste in the total waste generation. Due to its detrimental impacts on the environment and human health, several researchers have been striving to find effective methods to manage these large amounts of C&D wastes to minimise environmental impacts and maximise the economic and social benefits. Despite these efforts, limited studies have focused on comprehensively reviewing the integrated sustainable management of C&D waste. Thus, this study aims to conduct a comprehensive review of the published literature to identify barriers that hinder sustainable C&D waste management practices and map future research areas for effective C&D waste management. (2) Methods: A two-step systematic approach was adopted where the first step involved a bibliometric assessment of the published literature from 2002 to 2022, and then the most significant publications were reviewed from the bibliometric findings to achieve this study aim. (3) Results: The review findings identifies several research gaps which were categorised according to seven themes, including limitations in operational aspects, the lack of monitoring of legislation and regulations, an inadequate market for recycled products, inefficient stakeholder engagement and management, limitations of effective framework/models for sustainable C&D waste management, limited research on social performance, and inadequate integration of information technology in C&D waste management. This study’s findings are invaluable for researchers, industry professionals, and policymakers for in-depth understanding of the boundaries and potential future research areas to enhance sustainable C&D waste management practices
Preparation, characterisation and critical flux determination of graphene oxide blended polysulfone (PSf) membranes in an MBR system
No full textEvaluation of herbicide (persistent pollutant) removal mechanisms through hybrid membrane bioreactors
No full textImplications of short and long term critical flux experiments for laboratory-scale MBR operations
No full textThis paper evaluates the critical flux obtained by different techniques including tests with different flux step lengths (20 and 40 min and 7 days) and modes of operation (continuous and intermittent) under low and high MLSS concentrations. The paper also analyses a couple of long-term tests (flow rate of 40 and 20 L/day) to obtain the time required to reach the critical flux experimentally and compares those values with the results obtained numerically from a mathematical model. It was found that intermittent mode with membrane relaxation was useful in controlling the fouling of membrane and in restoring the membrane from fouling at lower MLSS
Removal of ametryn using membrane bioreactor process and its influence on critical flux
No full textCompared to the Conventional Activated Sludge Process (ASP), Membrane Bioreactors (MBRs) have proven their superior performance in wastewater treatment and reuse during the past two decades. Further, MBRs have wide array of applications such as the removal of nutrients, toxic and persistent organic pollutants (POPs), which are impossible or difficult to remove using ASP. However, fouling of membrane is one of the main drawbacks to the widespread application of MBR technology and Extra-cellular Polymeric Substances (EPS) secreted by microbes are considered as one of the major foulants, which will reduce the flux (L/m2/h) through the membrane. Critical flux is defined as the flux above which membrane cake or gel layer formation due to deposition of EPS and other colloids on the membrane surface occurs. Thus, one of the operating strategies to control the fouling of MBRs is to operate those systems below the critical flux (at Sub-Critical flux). This paper discusses the critical flux results, which were obtained from short-term common flux step method, for a lab-scale MBR system treating Ametryn. This study compares the critical flux values that were obtained by operating the MBR system (consisting of a submerged Hollow-Fibre membrane with pore size of 0.4μm and effective area of 0.2m2) at different operating conditions and mixed liquor properties. This study revealed that the critical flux values found after the introduction of Ametryn were significantly lower than those of obtained before adding Ametryn to the synthetic wastewater. It was also revealed that the production of carbohydrates (in SMP) is greater than proteins, subsequent to the introduction of Ametryn and this may have influenced the membrane to foul more. It was also observed that a significant removal (40-60%) of Ametryn from this MBR during the critical flux determination experiments with 40 minutes flux-step duration.<br
Performance of a laboratory-scale membrane bioreactor consisting mixed liquor with aquatic worms under toxic conditions
No full textEstimating design parameters for sustainable operation of a membrane bioreactor treating s-triazine herbicide
No full textThe potential of adopting struvite precipitation as a strategy for the removal of nutrients from pre-AnMBR treated abattoir wastewater
No full textImplications of short and long term critical flux experiments for laboratory-scale MBR operations
No full textThis paper evaluates the critical flux obtained by different techniques including tests with different flux step lengths (20 and 40 min and 7 days) and modes of operation (continuous and intermittent) under low and high MLSS concentrations. The paper also analyses a couple of long-term tests (flow rate of 40 and 20 L/day) to obtain the time required to reach the critical flux experimentally and compares those values with the results obtained numerically from a mathematical model. It was found that intermittent mode with membrane relaxation was useful in controlling the fouling of membrane and in restoring the membrane from fouling at lower MLSS.<br
