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Industrial and urban modernization processes generate significant amounts of heavy metal wastewater, which brings great harm to human production and health. The biotechnology developed in recent years has gained increasing attention in the field of wastewater treatment due to its repeatable regeneration and lack of secondary pollutants. Pseudomonas, being among the several bacterial biosorbents, possesses notable benefits in the removal of heavy metals. These advantages encompass its extensive adsorption capacity, broad adaptability, capacity for biotransformation, potential for genetic engineering transformation, cost-effectiveness, and environmentally sustainable nature. The process of bacterial adsorption is a complex phenomenon involving several physical and chemical processes, including adsorption, ion exchange, and surface and contact phenomena. A comprehensive investigation of parameters is necessary in order to develop a mathematical model that effectively measures metal ion recovery and process performance. The aim of this study was to explore the latest advancements in high-tolerance Pseudomonas isolated from natural environments and evaluate its potential as a biological adsorbent. The study investigated the adsorption process of this bacterium, examining key factors such as strain type, contact time, initial metal concentration, and pH that influenced its effectiveness. By utilizing dynamic mathematical models, the research summarized the biosorption process, including adsorption kinetics, equilibrium, and thermodynamics. The findings indicated that Pseudomonas can effectively purify water contaminated with heavy metals and future research will aim to enhance its adsorption performance and expand its application scope for broader environmental purification purposes. [ABSTRACT FROM AUTHOR]

The global concern over health issues related to heavy metal pollution has driven the adoption of various treatment technologies. The investigation into optimal conditions for cadmium biosorption and bioaccumulation was conducted using a resilient bacterial strain, Pseudomonas aeruginosa DR7, which was isolated from ponds. The equilibrium time of the adsorption process of living cells was much longer than that of non‐living cells, which was about 240 min, which indicates that living cells have intracellular accumulation and delay the adsorption process. Living cells favored a pH of 6.0, while non‐living cells showed higher efficiency at pH 7.0, demonstrating the pH‐dependent nature of metal biosorption. In this context, the maximum biosorption capacities for cadmium using non‐living cells and living cells were 103.8 mg/g and 70.94 mg/g, under cell mass of 1.0 g/L, pH 7.0, initial metal concentration of 200 mg/L, and contact time of 240 min, respectively. Cadmium biosorption by living cells was more accurately described by the Freundlich isothermal model, whereas the Langmuir model was used for non‐living cells. Living cells tend to show pseudo‐second‐order kinetic adsorption behavior, while non‐living cells tend to show pseudo‐first‐order kinetic adsorption behavior. Fourier‐transform infrared spectroscopy (FTIR) analysis suggested that the hydroxyl, amino, and carboxyl groups all play a role in biosorption. Scanning electron microscopy (SEM)–energy dispersive x‐ray spectroscopy (EDS) showed that the high‐temperature treatment destroys the integrity of the cell wall, which enhances the permeability of the cell wall, thus increasing the biosorption of Cd (II) by the non‐living cells. The study found that P. aeruginosa DR7 with high temperature inactivation has a higher Cd(II) adsorption capacity than living cells, making it a green and environmentally friendly biological adsorbent for wastewater treatment with heavy metals. [ABSTRACT FROM AUTHOR]

Water law aims to establish a legislative framework to meet water governance objectives. However, discrepancies may exist between the current legal provisions and the requirements for effective water quality protection and management. This research aims to investigate these discrepancies by analyzing the gap between actual law coverage and current water legislation, and to identify the necessary legal provisions for effective water management. The study employs an empirical literature review with an exploratory approach, utilizing a gap analysis framework that includes water institution mapping and water legislation mapping to evaluate the extent and efficacy of existing legislation. The gap analysis identified several deficiencies in the current water legislation, highlighting discrepancies and gaps in the legal framework for water quality protection and management. The research concludes that significant gaps in the current water legislation impede effective water quality protection and management. Addressing these gaps through comprehensive legislative reforms is essential to enhance water governance and ensure sustainable water management practices. [ABSTRACT FROM AUTHOR]

A conventional activated sludge (CAS) system has traditionally been used for secondary treatment in wastewater treatment plants. Due to the high cost of aeration and the problem of sludge treatment, researchers are developing alternatives to the CAS system. A membrane bioreactor (MBR) is a technology with higher solid-liquid separation efficiency. However, the use of MBR is limited due to inevitable membrane fouling and high energy consumption. Membrane fouling requires frequent cleaning, and MBR components must be replaced, which reduces membrane lifetime and operating costs. To overcome the limitations of the MBR system, a microbial fuel cell-membrane bioreactor (MFC-MBR) coupling system has attracted the interest of researchers. The design of the novel bioelectrochemical membrane reactor (BEMR) can effectively couple microbial degradation in the microbial electrochemical system (MES) and generate a microelectric field to reduce and alleviate membrane fouling in the MBR system. In addition, the coupling system combining an MES and an MBR can improve the efficiency of COD and ammonium removal while generating electricity to balance the energy consumption of the system. However, several obstacles must be overcome before the MFC-MBR coupling system can be commercialised. The aim of this study is to provide critical studies of the MBR, MES and MFC-MBR coupling system for wastewater treatment. This paper begins with a critical discussion of the unresolved MBR fouling problem. There are detailed past and current studies of the MES-MBR coupling system with comparison of performances of the system. Finally, the challenges faced in developing the coupling system on a large scale were discussed. [ABSTRACT FROM AUTHOR]

Various scenario classifications apply in an attempt to make the field of future studies easier to outline. This paper discusses the appropriateness of various creating, coordinating, and consistency procedures for creating specific emission scenarios in environmental assessments. The intuitive logics, story and simulation (SAS), social, technological, economic, environmental and political (STEEP), and La prospective models approaches are the five emission scenarios discussed in the paper analytically with their stages, storylines, steps, and building analysis. Every scenario method was examined and sorted into its separate benefits and limitations. Subsequently, the study selected the appropriate technique of emission scenario in environmental assessment with fulfilled scenario planning to deliver constructive scenarios. The study helps the aspiring designers by providing the fundamental guidance on the extensive change toward a sustainable environment. [ABSTRACT FROM AUTHOR]

A life cycle assessment study on decentralized sewage (DS) treatment technologies is conducted using Gabi software and ReCiPe midpoint method, focusing on three DS treatment technologies: extended aeration (EA), imhoff (IF) and activated sludge (AS). The three most significant environmental impacts identified by the analysis are climate change (CC), freshwater eutrophication potential (FEP) and marine eutrophication potential (MEP). In this study, none of the DS systems could reduce all three indicators assessed. In terms of CC, IF has the lowest impact, with a value of 2.78 kg CO2 eq/m3, while EA has the lowest FEP impact of 0.030 kg P eq/m3. As regards MEP, AS has the lowest value of 0.043 kg N eq/m3. The findings offer investors with relevant information on the effects of the three DS treatment technologies used to treat domestic wastewater in Malaysia. [ABSTRACT FROM AUTHOR]

Many advanced technologies have shown encouraging results in removing antibiotics from domestic wastewater. However, as activated sludge treatment is the most common sewage treatment system employed worldwide, improving its effect on antibiotic removal would be more desirable. Understanding the removal mechanisms, kinetics and factors that affect antibiotic removal in the activated sludge process is important as it would allow us to improve the treatment performance. Although these have been discussed in various literature covering different types of antibiotics and wastewater, a specific review on antibiotics and domestic wastewater is clearly missing. This review paper collates, discusses and analyses the removal of antibiotics from sewage in the activated sludge process along with the removal mechanisms and kinetics. The antibiotics are categorised into six classes: β-lactam, dihydrofolate reductase inhibitor, fluoroquinolone, macrolide, sulfonamides and tetracycline. Furthermore, the factors affecting the system performance with regard to antibiotic removal are examined. [ABSTRACT FROM AUTHOR]

The global transportation sector is one of the significant fuel consumers and contributes directly to greenhouse gas emissions due to fossil fuel consumption. Diesel blending used to reduce the reliant of fossil diesel in the transportation sector. Thus to reduce the environmental burden of fuel usage, new diesel blending formulations consist of biofuels were developed. The objective of the study is to assess the environmental performance of the five new diesel blending formulations with the existing diesel blending formulation by using Life Cycle Assessment method. In midpoint categories, the conventional B5 diesel blending has shown the lowest environmental impact compared to other fuels in most categories except for marine eutrophication, natural land transformation, ozone depletion, and terrestrial ecotoxicity. In the weighting stage, B5 diesel blending scored the lowest value and followed by blending 5, thus indicating its potential as an alternative to the existing diesel blending formulation. The presence of butanol in the new diesel blending majorly affects the environmental impact for many impact categories. [ABSTRACT FROM AUTHOR]

The Malaysian oil palm industry is one of the important contributors to the national economy, which improves the socio-economic of people, source of employment and eradicating poverty, but the industry is always scrutinised on its sustainability performance related to the human well-being and social issues. One of the approaches to address the associated social impacts in the oil palm industry is through social life cycle assessment (S-LCA). S-LCA was developed by the United Nations Environmental Programme and Society of Environmental Toxicology and Chemistry (UNEP/SETAC) to assess positive and negative social impact along the supply chain. The Sustainable Development Goals (SDGs) also has set the social criteria to move society towards the improvement of the well-being of people and surroundings. This study aims to assess the social impacts of the workers in the Malaysian oil palm industry using S-LCA and to indicate their connection with relevant SDGs. The system boundary of this study was from nursery, plantation up to palm oil mill where the worker's stakeholder categories were chosen. The S-LCA methodology was adopted from the UNEP/SETAC guidelines for the subcategory lists and the methodological sheet for indicators development. Out of eight worker subcategories, only six subcategories were assessed. The method assessment of this study using performance reference point using five classifications of level which are 1 - Excellent, 2 - Above average, 3 - Average, 4 - Below average and 5-Extremely poor) to gauge the organisation performance. The subcategory results ranged between 1 - 3 and indicated that some improvements are required for certain subcategories. Linking with SLCA and SDG showed that 6 out of 17 SDGs are relevant. LCA can be a tool to support oil palm businesses to achieve SDGs, but further explanation is needed to link LCA with SDGs since SDGs are conceptualised at the country or regional level whereas LCA is mainly used to gauge the impacts of products or services at the micro or business level. [ABSTRACT FROM AUTHOR]

Malaysia has committed to reduce its greenhouse gas (GHG) emissions by up to 45 % by the 2030. With increasing urbanisation and living standards of people in Malaysia, there is certainty that there will be a substantial increase in human activities hence mobility via networks of the highway. Rest and Service Area (RSA) is one important facility of the highway network that operates 24 hours and utilises significant amount of energy for its lighting, cooling, and the restaurants activities. A substantial amount of carbon is emitted from the RSA due to electricity usage, water consumption, solid waste and wastewater, as well as fuel consumption from staff commuting and transportation of goods. The objective of this study is to identify the sources and estimate the operational carbon footprint at RSA Highway Malaysia. The collected data questionnaire was analysed using Microsoft Excel. As expected, the amount of CO2 emissions from electric consumption for each selected RSA about 90 to 94 % of carbon release compare to other sources. As a conclusion, the investments including a more efficient HVAC system and more efficient lighting, could make the building more energy efficient and may induce greater use. [ABSTRACT FROM AUTHOR]

Palm oil is the most commonly used vegetable oil and is found in consumer products ranging from soap and chocolate to cooking oil. Approximately 90 % of global palm oil is supplied by Malaysia and Indonesia. In 2018, Malaysia and Indonesia set a target to increase their palm oil production to approximately 37.8 Mt and 20.5 Mt. It is anticipated that the palm oil residues generated from the production process will also increase. Palm oil mill residues such as oil palm fronds, oil palm trunks, palm oil mill effluent (POME), mesocarp fibres, palm kernel shells and empty fruit bunches have emerging potential to be converted into value-added products. This study focuses on POME because it has the potential to be used for the generation of renewable energy and Malaysia aims to utilise a greater amount of affordable, clean energy in line with the United Nations' Sustainable Development Goals. To this end, this study analyses and compares the CO2 equivalent (CO2-eq) of two palm oil mills (POMs 1 and 2) that use different POME treatment technologies, namely the covered lagoon bio-digester (CLB; POM 1) and the continuous stirred tank reactor (CSTR; POM 2) systems. The results of the analysis show that POM 1 produces 1,077.67 kg CO2-eq, which is lower than that produced by POM 2 which emits 1,429.28 kg CO2-eq. [ABSTRACT FROM AUTHOR]

This paper presents a study on the performance of an Aerobic Submerged u-shaped membrane bioreactor (ASMBR) in treating sulfidic spent caustic (SSC) in terms of mixed liquor suspended solid (MLSS) concentration and solid retention time (SRT). SSC wastewater is categorized as high strength wastewater and consists of high inorganic and organic matter. U-shape membrane bioreactors have a higher tendency to foul compared to other types of MBR. MLSS concentration and SRT are the major parameters when operating membrane bioreactor. In this study, COD removal recorded reduction of more than 95% for average MLSS concentration runs and 90% for SRTs runs. Meanwhile, sulfide was removed 99%, and formed up to 79% of sulfate. The biofouling for MLSS concentration and SRTs were observed through TMP rate change and TMP average performance, TMP trend and SMP and EPS trends. Biocake layer and biolayer deposited on membrane surface was found influenced by biomass, the inert particulate biomass products accumulating in the reactor. [ABSTRACT FROM AUTHOR]

Addressing environmental degradation and ensuring environmental sustainability are inextricably linked to all methods of reducing volatile organic compounds (VOCs) from the environment. A packed column air stripper is a typical example of such technologies for the removal of VOCs from polluted water. The present review is devoted to the applications of a packed column air stripper and, in comparison with previous reviews, presents further elaborations and new information on topics such as modeling and simulation of the dynamic behavior of the air stripping process in a packed column air stripper. The paper observed that a knowledge gap still exists in the synthesis of this knowledge to formulate practically applicable mathematical relationships to describe the process generally. Therefore, further researches are still required in the area of air stripper performance optimization, particularly in the development of a mathematical model and the optimization of an air stripper using a statistical experimental design method. Such a determination is critical to the understanding of the interactive effect of process variables such as temperature, air-to-water (A/W) ratio, and height of packing on air stripper performance. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to compute the amount of methane generated from the waste of livestock from 1980 to 2008; then use the information in forecasting subsequent methane emissions by the sector in Malaysia from 2009 to 2020. Design/methodology/approach -- The research study employed two approaches; computing methane emissions from 1980 to 2008 using the IPCC guidelines, and forecasting methane emissions for the animals from 2009 to 2020 using the autoregressive integrated moving average (ARIMA) model from the predictive analysis software (PASW-SPSS 18.0). Findings -- Methane emissions from cattle, buffaloes and pigs accounted for over 95 per cent of total emissions and emissions from cattle are predicted to increase from 67.0 Gg in 2009 to 77.0 Gg by 2020. Emissions from the others will not be appreciable although poultry emissions will rise to 11.0 Gg by 2020. Attempt by the Malaysian Government to increase cattle production is not necessary at the moment as protein requirement has been met. Research limitations/implications -- ARIMA model suffers from linear and data limitation: the future value of a variable assumed to be a linear function of several past observations in ARIMA is sometimes unrealistic. Large amounts of historical data are needed in ARIMA models in order to get desired results. The inventory of the animals was taken from 1980 to 2008.This needs to be improved upon by updating it to cover up to 2011 so that the forecast will start from 2012. Practical implications -- The chosen ARIMA method has demonstrated its correctness in being adequate as a predicting tool for animal methane emissions. Policy makers can apply it so as to take practical steps to avoid these emissions. Originality/value -- This is a novice idea as animal methane emission forecasting tool. This model will be of immense use and help in predicting methane emissions from livestock. [ABSTRACT FROM AUTHOR]

The problem of massive emissions of carbon dioxide (CO2) from the burning of fossil fuels and their climatic impact has become major scientific and political issues. Electricity generation, transportation, industrial and residential are the main sectors identified to contribute to the emission of CO2 in Malaysia. In this study, a comprehensive modeling tool, long-range energy alternatives planning system (LEAP) was utilized to project CO2 emissions from year 2000 to year 2020 for each sector. It was projected that without any mitigation measures being taken up by the country, 285.73 million tonnes of CO2 will be released in 2020, which is a 68.86% increase compared to the amount of CO2 emitted in year 2000. Electricity generation, which gives 43.40% out of total of emissions, was discovered to be the largest emitting sector among all sectors. In addition, this study also reviews recommended mitigation analysis proposed by other researches as well as implementation of energy efficiency program in Malaysia. This projection and mitigation is a hope to provide an important basis to reduce future CO2 emissions and their associated impact in Malaysia. © 2010 American Institute of Chemical Engineers Environ Prog, 2010. [ABSTRACT FROM AUTHOR]

Tannery wastewater treatment using two isolated micro-organisms (Bacillus subtilis and Pseudomonas fragii) has been investigated in the present study. The growth patterns, pH normalisation and the abilities of these micro-organisms to reduce the concentrations of chemical oxygen demand (COD), total suspended solids (TSS) and chloride were studied using the shake flask apparatus. The specific growth rate and biomass concentration of B. subtilis and P. fragii were observed 0.138 h-1 and 3.01 mg/l and 0.051 h-1 and 2.34 mg/l, respectively, after 84 h. Both micro-organisms normalised pH of the wastewater. COD removal efficiency for B. subtilis was 87.6% while that of P. fragii was 85.2%. For TSS, B. subtilis caused a reduction of 91.7% (from 876 mg/l to 73 mg/l), while P. fragii reduced the solid concentration from 876 mg/l to 98 mg/l (88.8%). B. subtilis could only achieve 48.5% reduction in chloride concentration (from 127.08 mg/l to 65.39 mg/l compared to a reduction of 54.6% (from 127.08 mg/l to 57.72 mg/l) for P. fragii. From the results, it can be said that the bacteria present in tannery effluents have significant potential in treatment of tannery wastewater. [ABSTRACT FROM AUTHOR]