Volume 2 Issue 9

Authors: Shin’ichi Okamoto; Arpa Wangkiat; Prapat Pongkiatkul; Nguyen Thi Kim Oanh; Chaloemchai Nakkhwan

Abstract: The positive matrix factorization (PMF) and the chemical mass balance (CMB) models were applied to the source apportionment of ambient PM study for a coastal industrial area. The PMF result for coarse fraction was similar to that of the CMB model. As for coarse fraction, correlation coefficients for the calculated contributions by the PMF and CMB models for individual samples were larger than 0.6 for the source categories of sea salt, soil and steel mill. As for the fine fraction, the PMF could also identify the following emission sources: steel mill, soil, Cl and NO3 rich secondary particle, aged sea salt, SO4 rich secondary particle, and refuse burning. However the CMB result for fine fraction was not satisfactory due to higher ratio of secondary particles.

Keywords: Particulate Matter; Source Apportionment; Receptor Model; CMB and PMF


Authors: M. Rezayi; A. S. Esmaeli; T. Valinasab; J. Alavi

Abstract: This research was carried out to compute the total mercury and selenium determined in tow commercial fish from Persian Gulf and Selenium Health Benefit Value (SEHBV) of each species. The average ±SD concentration of Hg and Se in edible part of Pesttodes Erumei were 0.077±0.062 and 0.044±0.018 μg/gww, respectively and their values in liver correspondingly were 0.127±0.122 and 0.132±0.061 μg/gww. The average concentration of Hg and Se in edible and liver part of Otolithes Ruber were 0.348±0.27, 0.060±0.021, 0.176±0.174 and 0.093±0.022 μg/gww, respectively. Selenium Health Benefit Value (SEHBV) was positive (1.0) in Pesttodes erumei and negative (-6.2) in Otolithes Ruber. It reveals the fact that Selenium Health Benefit is negligible in both species to reduce mercury bioavailability.

Keywords: Selenium; Mercury; Selenium Health Benefit Value (SEHBV); Persian Gulf


Authors: Goen Ho; Jaya Nair; Xian Fang Lou

Abstract: Food water composition and the amount of water addition are strong determinants of a digester’s performance. Hence, the objective of this paper is to study how variations in the majoring food groups and water additions can affect digester performance. The performance of carbohydrate, protein, lipid and cellulose rich mixed food wastes, subjected to five factors of volumetric dilution, were evaluated in a controlled laboratory scale set up at 38°C and 28°C. Substrate degradation was high for all assays with 86.6 – 100% and 87.1 – 98.0% reduction in VS and COD respectively. Maximum methane (CH4) yield varied between 362.7 (carbohydrate at 1:2 dilution) and 0.53 m3 CH4/kg VS (protein at 1:6 dilution) at 38°C and 0.32 (lipid at 1:2 dilution) and 0.52 m3 CH4/kg VS (protein at 1:6 dilution) at 28°C with the maximum rate of CH4 production varying between 0.015 (lipids at 1:2 dilution) and 0.053 m3 CH4/kg VS/day (protein at 1:6 dilution) at 38°C and between 0.006 m3 CH4/kg VS/day (lipids a 1:2 dilution) and 0.026 (protein at 1:6 dilution) m3 CH4/kg VS/day at 28°C. Lipid rich waste obtained the lowest yield while cellulose and protein showed interchangeably the highest yield. To successfully digest lipid rich waste a dilution no less than 1:4 was required to improve CH4 generation and to drastically reduce retention time. Both Bo and maximum rate of CH4 production increased as dilution factor and temperature increased while lag phase decreased. Results indicate that with sufficiently long retention time, food waste up to a dilution of 1:2 did not experience irreversible inhibition problems and achieved high substrate degradation although sufficient water additions can significantly improve a digester’s lag time and CH4 generation potential.

Keywords: Food Waste; Anaerobic Digestion; Kinetic Study; Small Scale; Methane; Organic Loading Rate


Authors: Anupam Singhal; Satya Prakash; V.K. Tewari

Abstract: This solid waste may contaminate surface run-off and surface water. In stainless steel pickling industries, a lot of sludge is generated and disposal of above sludge as per Act of Hazardous Waste (Management & Handling) Rules, 1989 is not easy. In the normal practice, the sludge is being disposed off on both sides of roads and railway tracks to fill low lying areas. This causes a severe problem, because during rains, the entire toxic compound (leachate) goes into ground and pollutes the ground water. Seeing the above problem, a study is taken for utilization of pickling sludge with fly ash to avoid the problem of disposal. Cement concrete hollow cavity bricks can be made and compressive strength of cement concrete hollow cavity brick is found to increase with addition of 7.5% TSLS (treated spent liquor sludge) and 15% fly ash as a partial replacement of cement. Formation of C-S-H gel may be contributing to increase in compressive strength.

Keywords: Hazardous Waste; Pickling; Sludge; Brick


Authors: Ajay S. Kalamdhad; Jiwan Singh

Abstract: Composting is becoming a more acceptable and economical method for treating sewage sludge, municipal solid waste, tannery waste, pig manure, poultry manure, etc.. The application of compost formed by above waste material to land can be used as soil fertilizer/conditioner due to presence of nitrogen, phosphorus, potassium and other nutrients. However, presence of heavy metals in the compost restricts its use as soil conditioner. Heavy metals uptake by plants from the soil and successive accumulation in human tissues and biomagnifications through the food chain causes both human health and environment concerns. Heavy metals from the compost can be reduced by addition of some chemicals (natural zeolite, red mud, lime, sodium sulfide, bamboo charcoal and bamboo vinegar, etc.) and biological agents during composting process. Biological agents such as Phanerochaete chrysosporium that is a fungus has been used to remove Lead (Pb) from the compost and earthworm can accumulate the high concentration of heavy metals in the non-toxic forms and be capable of reducing possible toxic effects of unessential heavy metals by utilizing them for physiological metabolism. The principal advantage claimed for biological process over the use of chemicals during composting is the low capital cost. Therefore, the present study gives an overview of the various heavy metal reduction techniques from the composting of various wastes materials carried out by different mode of operation.

Keywords: Composting; Heavy Metals; Soil Contamination; Reduction


Authors: Agnes G. Mwakaje

Abstract: Artisan and small-scale mining (ASM) plays an important role in employment and livelihoods in Tanzania. Estimates suggest that over 1,000,000 Tanzanians are engaged in mining, more than 90 percent of whom are in ASM. However, most ASM activities are taking place using rudimental technology causing negative impact on the environment and human health. Despite having laws and regulations in the mining sector in the country, the enforcement at the ASM has remained ineffective. There is a concern that the institutional framework governing the Mining Sector is not suitable for ASM and innovations are required to effectively governing the ASM activities. This study is a contribution towards achieving this goal. The study conducted a review of the institutional framework governing ASM, focusing on the gold subsector. It also undertook a comprehensive review of literature on ASM. In addition, about 100 ASM operators were interviewed in Nyarugusu area, Geita district. The study intended to highlight the strengths and weaknesses of the current institutional framework for ASM operators and suggests innovations to inform the policy and decision making process on how best ASM could enhance livelihoods without degrading the environment. It also adds to the body of knowledge on the current debate of environmental degradation under ASM through publication. The major conclusion is that the current institutional framework is not conducive for ASM activities and innovations are necessary for ASM operators to comply. Most of the decision making and compliancy regulatory bodies are centralised, a high number of ASM operators are not aware of the existing institutional framework and most of the regulations are not compatible with the ASM activities. These include the requirement for ASM operators to register their activities at the head quarters of the Ministry, the condition that each ASM operator to undertake environmental impact assessment (EIA) in his/her plot, insufficient involvement of local authorities at village and district levels to regulate the ASM activities, poor working technology and lack of ASM organisations/associations. The following innovations are recommended: decentralising ASM regulations to village and district levels including capacity building at these levels, introducing block EIA and management plans to accommodate a number of ASM operators and for joint responsibilities, strengthening cooperatives and associations, facilitating ASM operators access to credit and link ASM with medium/large scale mining and providing friendly formalisation processes.

Keywords: ASM; Environmental Degradation; Institutional Framework; Innovations