Seksan Papong

Life-cycle energy and environmental analysis of bioethanol production from cassava in Thailand

In this study, the life-cycle energy and environmental assessment was conducted for bioethanol production from cassava in Thailand. The scope covered all stages in the life cycle of bioethanol production including cultivating, chip processing, transportation and bioethanol conversion. The input-output data were collected at plantation sites and ethanol plants which included materials usage, energy consumption, and all emissions. From the energy analysis, the results show that cassava-based bioethanol has a negative net energy value with an energy ratio was less than 1, indicating a net energy loss. For the environmental performance, the results show that throughout the life cycle of bioethanol, the conversion stage contributes most to the environmental impacts which is due to the use of coal for power and steam production in the bioethanol plants. It is suggested that a partial substitution of coal with biogas produced from existing wastewater treatment could lead to a significant reduction in the environmental impact.

Characteristics and Environmental Assessment of Facing Bricks Produced from Dredged Sediments and Waste Glasses

The laboratory-scale study was conducted to assess the feasibility of using dredged sediments with waste glasses to produce facing bricks. This study was investigated into three different proportions of waste glasses ranging from 0, 20, and 40% by weight mixed with dredged sediments as raw materials in producing facing bricks. The characteristics of the dredged sediments, waste glasses, and fired facing bricks were analyzed using X-ray fluorescence (XRF) and X-ray diffraction (XRD. The physical-mechanical properties of fired bricks were compliant with the criteria for facing bricks (Thai Industrial Standards 168-2546). The results showed that major chemical compositions of dredged sediments and waste glasses were silica (SiO2) with the value of 43.50% and 70.70%, respectively. Heavy metal contents including Cr, Cu, Zn, As, Cd, Hg, Pb, Mn, Sr, and Ni were lower than the soil quality standard. Results of this study indicated that dredged sediments and waste glasses are suitable as primary raw materials in the production of facing bricks and could be considered to represent an environmental friendly product.

Material Flow Analysis (MFA) and Life Cycle Assessment Study for Sustainable Management of PVC Wastes in Thailand (Phase III)

Abstract Polyvinyl chloride (PVC) is one of the most commonly used plastics in the worldwide. In Thailand, PVC products are used for domestic consumption more than 400,000 tons annually. After discarded, these products will become wastes which are being accumulated and could cause several environmental problems if they are disposed by inappropriate method. In previous studies, our group investigated the material flow of PVC in Thailand to handle the PVC waste problems systematically and effectively. Material Flow Analysis (MFA) model was developed to estimate the quantity and route of PVC wastes in Thailand using annual production data from 1971-2014 as an input in the model along with an average service life time of each product. In addition, the primary data were collected from recycle shops and landfill sites were used to estimate the amount of PVC wastes that are generated and recycled on yearly basis, and recycling ratio of each PVC product in Thailand. The results indicated that some selected PVC products were effectively recycled such as pipe, cable, and hose but the other products were relatively low portion in recycling. This is the first time that the MFA of PVC wastes and PVC recycling are revealed which could be a potential model for other plastics in Thailand. In this work (phase III), firstly, the MFA model was developed by considering consumer behaviour and economic decisions. Sheet & film product were included in this investigation in order to expand range of PVC products, in which covers about 93% of total PVC products in Thailand. In addition, the existing primary data were revised along with the new data were from other recycle shops and converters. Finally, potential improvements of PVC waste management and suitable data collection system are proposed in order to promote environmentally friendly schemes for PVC production and utilization.