Radiant Domestic Combustion Stove System: Experimental and Simulated Study of Energy Use and Thermal Comfort

A steady-state space radiant heat model and a stove combustion model are developed to simulate the heat exchanges between various surfaces in the room and the stove and stack surfaces, assuming stiochiometric combustion inside the stove and the exhaust gases flow out through the stack by natural convection. The space heat model calculates the fuel consumption, the stove, stack temperatures, and the mass flow rate of exhaust gases, and provides an opportunity to study the energy efficiency of the stove, while satisfying the constraints of thermal comfort. Fanger (1982) Fanger, P. O. 1982. Thermal Comfort Analysis and Applications in Engineering, 156–198. New York: McGraw Hill.  [Google Scholar] model and a radiation exchange model between various surfaces of the space, the thermal building energy balance, and stove combustion process is applied to determine the mean radiant temperature (MRT) and the extent of thermal comfort as determined by predicted mean vote (PMV).

The overall model is validated by performing experiments in a room placed inside a controlled outdoor environment. The room is heated using a domestic stove common for rural areas of Lebanon and the MRT, the room air temperature, the walls and window temperatures are measured at two stove positions. The measured MRT, the average room temperature, and the wall surface temperatures agreed within ±7% of values predicted by the numerical model.

A parametric study is performed to optimize the stove and occupant locations in the room where adequate comfort level can be maintained at lower fuel consumption levels. The values of MRT and PMV depend strongly on the position of the radiant stove heater and stack with respect to the cold window and the occupant location. It is shown that it is possible to save up to 15% in stove fuel consumption by changing the stove position in the room with respect to the window and to the person, while maintaining the same level of comfort.     

Cost-effective treatment of sludge conditioning using supernatant fluid polyelectrolyte

Environmental Science and Pollution Research - Treatment of activated sludge using pure polyelectrolyte and its supernatant fluids for sludge dewatering was examined. The supernatant was used for...     

Sediment microbial fuel cells for bioremediation of pollutants and power generation: a review

Environmental Chemistry Letters - Worldwide pollution of almost all natural media by toxic compounds is a major public health issue requiring the development of advanced remediation techniques such...     

Assessing the long- and short-run asymmetrical effects of climate change on rice production: empirical evidence from India

Environmental Science and Pollution Research - In recent years, environmental change has arisen as a ubiquitous problem and gained environmentalist’s attention across the globe due to its...     

On Sustainable Development of Social Forestry in Bangladesh: Experiences from Sal (<Emphasis Type="Italic">Shorea Robusta</Emphasis>) Forests

Sustainability in forestry is a complex amalgam of trade-offs among its various dimensions and there is no easy route to achieve sustainable development. It is important that policy process and implementation strategy of these policies should be based on sound information about these trade-offs. There is a growing consensus amongst key forest decision-makers in Bangladesh that traditional forestry is needed to make the transition to more sustainable forestry, which is likely to involve local people in forest management. As a result, the government has initiated a social forestry program from 1981 with the assistance of the Asian Development Bank (ADB) loan and the United Nations Development Program (UNDP) grant and operated mainly in Sal forest areas. The most important objective of this program is to protect, manage, and develop forests in a sustainable way by involving local communities. Although several studies have focused on the management issues of social forestry, none of these studies has evaluated the indicators of sustainable social forestry. The purpose of this study is to evaluate the criteria of sustainable development of social forestry in Bangladesh. The study is based on primary cross-sectional data collected using the multistage stratified sampling technique. In total, 581 social forestry farmers were selected randomly and interviewed using a pre-tested questionnaire. The study evaluated some important components of sustainable development and identified the following conditions of social forestry in Bangladesh:(i) almost all the components of sustainable development of social forestry, although not at the aspiration level, were at good condition;(ii) participants were interested and committed to work with Forest Department in developing social forestry;(iii) they had been utilizing both hard and soft technology in practicing social forestry, although there exists ample scope of development;(iv) income of participants after involving in social forestry had increased, although not at satisfactory level; and(v) process of producing social and material goods had been under progress.However, there exist plenty of scopes for sustainable social forestry development through improving the sustainable development components more carefully.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Factors Affecting Participating Farmers’ Willingness-to-pay for the Tree Farming Fund: A Study in a Participatory Forest in Bangladesh

This paper examined the factors that might influence participating farmers’ willingness-to-pay for the Tree Farming Fund (TFF) established for sustainable development of participatory forest management (PFM). Information on willingness-to-pay, socioeconomic characteristics, and attitudes of participating farmers toward TFF were obtained from interviews with 581 participating farmers. Logistic regression analysis was used to determine the dominant factors that might influence participating farmers’ willingness-to-pay for the TFF. The results showed that participating farmers’ willingness-to-pay was significantly affected by (i) family income; (ii) education level; (iii) confidence that his aspired benefits will be received; (iv) agreement with the statement that ‘PFM is sustainable under the present state of management’; (v) agreement with the statement that ‘PFM is a good strategy for forest conservation’; and (vi) knowledge of PFM strategies. Thus, participating farmers with a higher level of education, higher income and positive attitudes toward TFF tended to express more willingness-to-pay. Establishment of TFF could be an effective strategy in implementing sustainable PFM in Bangladesh. For this strategy to succeed, however, active partnership between the participating farmers and Forest Department is required. Participating farmers’ attitudes toward TFF should therefore be taken into consideration as should the results of this study, which are important indicators of participating farmers’ positive attitudes toward TFF.     

Particulate matters and gaseous pollutants in indoor environment and Association of ultra-fine particulate matters (PM1) with lung function

Environmental Science and Pollution Research - Real-time particulate matters (PM1, PM2.5, PM4, PM7, PM10, and TSP) with AEROCET 531S (USA), gaseous pollutants (NO2 and TVOC) with Aeroquel 500 gas...     

Photocatalytic degradation of endocrine disruptor Bisphenol-A in the presence of prepared CexZn1-xO nanocomposites under irradiation of sunlight

Photocatalytic degradation of Bisphenol A （BPA）, a representative endocrine disruptor chemical, was carried out under irradiation of sunlight in the presence of CexZn1-xO nanophotocatalyst. Cerium （Ce） ions were successfully incorporated into the bulk lattice of ZnO by simple co-precipitation process. The CexZn1-xO composite nanostructures exhibited higher photocatalytic efficiency than pure ZnO in the degradation of BPA under sunlight irradiation and nearly complete mineralization of BPA was achieved. The degradation rate was strongly dependent on factors such as the size and structure of catalyst, doping material concentration, BPA concentration, catalyst load, irradiation time and pH levels. This work suggested that the CexZn1-xO assisted photocatalytic degradation is a versatile, economic, environmentally benign and efficient method for BPA removal in the aqueous environment.     

Adsorptive removal of iron and manganese ions from aqueous solutions with microporous chitosan/polyethylene glycol blend membrane

Microporous chitosan (CS) membranes were directly prepared by extraction of poly(ethylene glycol) (PEG) from CS/PEG blend membrane and were examined for iron and manganese ions removal from aqueous solutions. The different variables affecting the adsorption capacity of the membranes such as contact time, pH of the sorption medium, and initial metal ion concentration in the feed solution were investigated on a batch adsorption basis. The affinity of CS/PEG blend membrane to adsorb Fe(II) ions is higher than that of Mn(II) ions, with adsorption equilibrium achieved after 60 min for Fe(II) and Mn(II) ions. By increasing CS/PEG ratio in the blend membrane the adsorption capacity of metal ions increased. Among all parameters, pH has the most significant effect on the adsorption capacity, particularly in the range of 2.9-5.9. The increase in CS/PEG ratio was found to enhance the adsorption capacity of the membranes. The effects of initial concentration of metal ions on the extent of metal ions removal were investigated in detail. The experimental data were better fitted to Freundlich equation than Langmuir. In addition, it was found that the iron and manganese ions adsorbed on the membranes can be effectively desorbed in 0.1 mol/L HCl solution (up to 98% desorption efficiency) and the blend membranes can be reused almost without loss of the adsorption capacity for iron and manganese ions.     

Comparison of jatropha and karanja biofuels on their combustion characteristics

Biofuel blends produced from Jatropha (Jatropha curcas) and Karanja (Pongamia pinnata) oil were evaluated for their combustion properties. Two kinds of blends (regular diesel with Jatropha and Karanja oil) were prepared at 20% volume to the diesel and tested as alternative fuels in single cylinder (vertical), water-cooled, direct injection diesel engine at the rated speed of 1500 rpm. The performance of the engine in terms of thermal efficiency at full load for diesel was 30%. For Jatropha and Karanja biodiesel blends, the thermal efficiencies were 29.0% and 28.6%, respectively. The maximum cylinder pressure and ignition delay for biodiesel fuel blends are very close to that of regular diesel. Prolonged combustion was observed for Karanja oil blend in comparison to Jatropha oil blend. The combustion pattern also reveals the slow burning characteristics of vegetable oils and this study indicates that the blended biofuels have combustion characteristics that are similar to regular diesel fuels.