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Different mixture ratio of household organic waste (HOW) and cow manure (CM) were investigated for biogas production. The objective was to explore possible significant synergistic effect obtained from the combination of these different substrates in Reactor 1 – 4 (R 1 – 4 ) batch experiment. The highest methane yield, 247 mL/g VS was obtained from R 3 and 243 mL/g VS in R 4 . Co-digestion in R 4 increased to 9% for CM and 78% for HOW in methane production. The results clearly demonstrate synergistic effect from nutrient balanced that improves the stability of anaerobic process. [ABSTRACT FROM AUTHOR]

Recycling programmes have been conducted by various stakeholders including Government sector and private sector to reduce waste generation from being disposed into the landfill. The objectives of this study was identifying the correlation between the community participation in recycling programme and community attitude and their knowledge on solid waste segregation. The fully structured questionnaires were filled in by 382 respondents through random sampling. The result shows that there was a weak and positive correlation between community participation in recycling programme with community attitude on solid waste segregation, r = 0.343; and community knowledge on solid waste segregation, r = 0.251. Policy review by Government is highly recommended to identify the factors that can influence more community participation in recycling programmes. [ABSTRACT FROM AUTHOR]

Abstract: Rapid economic development and population growth, inadequate infrastructure and expertise, and land scarcity make the management of municipal solid waste become one of Malaysia’s most critical environmental issues. The study is aimed at evaluating the generation, characteristics, and management of solid waste in Malaysia based on published information. In general, the per capita generation rate is about 0.5–0.8kg/person/day in which domestic waste is the primary source. Currently, solid waste is managed by the Ministry of Housing and Local Government, with the participation of the private sector. A new institutional and legislation framework has been structured with the objectives to establish a holistic, integrated, and cost-effective solid waste management system, with an emphasis on environmental protection and public health. Therefore, the hierarchy of solid waste management has given the highest priority to source reduction through 3R, intermediate treatment and final disposal. [Copyright &y& Elsevier]

This study developed hybrid briquettes using corncobs and the bark of oil palm trunk (OPTB). The objective was to assess the performance of the briquettes in a cooking application as a potential fuel source for domestic utilization. Corncob was mixed with OPTB in ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 by weight, and wastepaper pulp (10% by weight) was added to each mixture as the binder. The mixtures were densified manually at room temperature using a 20-tonne hydraulic piston press under a ≤7 MPa compaction pressure. The calorific value of the briquettes was determined by a bomb calorimeter, while other fuel properties were determined by proximate and ultimate analysis. The briquettes' performance was evaluated by a water boiling test, and gaseous emission was determined and reported based carbon-dioxide equivalent (CO 2 e). Results showed that the volatile matter, ash content, and calorific value increased with the increase in OPTB in the ratios while fixed carbon decreased. Additionally, briquettes produced from ratios 50:50 and 25:75 were similar in values based on the total time taken to ignite briquettes and boil 1 L of water (17.54 min and 17.13 min), fuel burning rate (0.69 kg/h and 0.70 kg/h) and specific fuel consumption (0.16 kg/l and 0.15 kg/l). However, ratio 50:50 performed better in terms of thermal fuel efficiency (17.25%) and produced less ash during combustion and thus, is considered the optimum combination. Greenhouse gas emission of all briquettes ranged from 241 to 281 gCO 2 e. The results suggest the possibility of producing briquettes with adequate fuel properties for combustion from a blend of corncobs and OPTB. The calorific value and performance of the hybrid briquettes have confirmed and justified the use of OPTB, which have previously not been used for briquette production, thus making a novel contribution to biomass options. The study shows a means of reducing waste, energy shortages, and indoor air pollution in rural communities in Nigeria. Overall, the hybrid briquettes are sustainable, environmentally friendly and cost-efficient compared to fossil fuels. • Oil palm trunk bark blended with corncobs can make quality hybrid briquette. • Calorific value is an important parameter for characterizing briquettes as fuel. • Greenhouse gas emission based on carbon dioxide equivalent was determined. • Hybrid briquettes are environmentally friendly, cost effective and affordable. • Rural communities in Nigeria will benefit from the application of these briquettes. [ABSTRACT FROM AUTHOR]

Selecting the optimal wastewater treatment technology (WTT) is one of the biggest challenges in the sustainable management of industrial wastewaters. In Iran’s economy, the strategic role of the steel sector highlights its importance in sustainability assessments. Using Iran’s steel industry as a case study, this paper develops an integrated methodology for determining the most appropriate WTT. Since, the most common approach for technology evaluation, in both developed and developing countries, is expert judgment, this issue is studied by means of a multi-dimensional approach that considers the sector characteristics; the interaction of the technical, environmental and economic aspects; and the specific preferences in developing countries. The proposed modelling framework presents a rational decision-making process based on two multi-criteria decision-making (MCDM) techniques including the Analytic Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) in combination with fuzzy logic to make use of the combined benefits of several methods The methodology is carried out as a stepwise procedure and the fuzzy concept is introduced in both the weighting and ranking procedures. The most commonly used industrial WTTs in the steel industry are identified and ranked with respect to the six evaluation criteria and their thirty associated indicators. Finally, the results from different models, with crisp and fuzzy values, are compared to propose a straightforward and pragmatic operational decision tool. The study indicates that a hybrid model of AHP, TOPSIS and fuzzy logic offers better results and provides a higher degree of confidence for sophisticated judgments. According to the findings, the experts largely prefer the more advanced treatment systems, such as “Electrolytic splitting with Reverse osmosis and Evaporation in addition to the conventional technologies” because of their high system efficiency and compatibility with environmental impact criteria. This approach can be applied for other sectors at any industry level of decision-making—from the level of individual plants to national. [ABSTRACT FROM AUTHOR]

Metals accumulating in mud crab from Indonesia's East Java estuaries have been assessed for potential health effects. Mud crabs from the Solo River estuary (JS) had the highest levels of all metals tested when compared to mud crabs from the Brantas River estuary (MS) and the Banyuwangi coastal area (BS). Metal accumulation in mud crabs occurred in the following order: Zn > Cu > Cr > Pb > Cd > Hg. The estimated weekly intake values for all metals from all stations were less than the provisional tolerable weekly intake requirement. Similarly, all metal target hazard quotient values from all stations were less than one, suggesting that all metals were within the allowable intake limit. The target cancer risk values for Cd and Cr, on the other hand, were somewhat higher than 10-4, indicating that they were dangerous for human ingestion and possibly linked to a risk associated with carcinogenic agent exposure over a lifetime. • In mud crabs, metal accumulation happened in the following order: Zn > Cu > Cr > Pb > Cd > Hg. • The highest levels of all metals were found in mud crabs from the Solo River estuary (JS). • Cd and Cr had the cancer risk values based on daily ingestion. [ABSTRACT FROM AUTHOR]