Vol. 2 Issue 3 Jul.-Sep. 2011

K. Anandavelu*, N. Alagumurthi and C.G. Saravannan

Abstract: The aim of this study is to partial replacement of diesel fuel with eucalyptus oil and experimentally determines their effects on the engine performance, combustion and exhaust emissions such as brake specific energy consumption (BSEC), brake thermal efficiency (BTE), heat release rate, cylinder pressure and emissions such as smoke density, carbonmonoxide (CO), unburned hydrocarbon (UBHC) and oxides of nitrogen (NOx). For this purpose, five different blends containing 10, 20, 30, 40 & 50% of eucalyptus oil with diesel fuel were prepared in volume basis and tested in naturally aspirated direct injection kirloskar TV1 diesel engine with constant speed of 1500 rpm at varying load conditions. Results indicated that the brake thermal efficiency is increased about 6.2% for 60:40 DF/EOF blend (blend has 60% of diesel and 40% of eucalyptus oil) as compared to standard diesel fuel (DF) operations. Further the results showed that at full load condition, 60:40 DF/ EOF blend have 16.7%, 25% and 15.15% reduction of smoke, CO and UBHC respectively as compared to standard DF. NOx emission is slightly reduced about 0.97% for 60:40 DF/ EOF blend as compared to DF. The heat release rate and cylinder pressures are increased positively.

Keywords: Biofuel, Eucalyptus, Performance, Emission, Diesel engine.

S. Chooklin*, L. Kaewsichan and J. Kaewsrichan

Abstract: Lactic acid is a product that has several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work was to evaluate the potential use of sap of oil palm (Elaeis guineensis) as a substrate for lactic acid production by Lactobacillus casei TISTR 1500. The effects of constant pH at 5.5 in a 2 L bioreactor and supplementary de Man, Rogosa, Sharpe (MRS) medium with oil palm sap as a carbon source on fermentation performance were investigated. In this report, when oil palm sap was used as a carbon source for L. casei TISTR 1500, constant pH at 5.5 did not significantly affect lactic acid production. The addition of MRS medium improved the biomass and the product yield of oil palm sap. Fermentation runs pH-unfixed gave an improved productivity of 0.55 g L-1 h-1 during the fermentation containing 100 mL of oil palm sap (20 g L-1 of total sugars) supplemented MRS medium in flasks under static condition at 37°C. Oil palm sap could serve as a good potential source of raw materials for the efficient production of lactic acid by L. casei TISTR 1500.

Keywords: Fermentation; Lactic acid; Lactobacillus casei; Oil palm sap; Palm Oil.

V.N. Thai*, A. Tokai, Y. Yamamoto and D.T. Nguyen

Abstract: Developing countries are confronted with difficulties in implementing eco-labeling schemes when they adopt eco-labeling criteria from developed countries. Production-related criteria, in particular, must reflect the availability of necessary infrastructures and local conditions. This study identified such criteria in a case study of the Vietnamese textile industry. It aims to (1) understand textile flows by using the mass balance concept and the combination of available data (which is insufficient) in Vietnam and previous reports and (2) identify production-related eco-labeling criteria from resource consumption, 46 pollutants and toxicants discharged by the textile industry. The results show that, in 2008, 1.67×106 tons of textiles flowed through Vietnam, approximately 19.4 kg/person. Textile manufacturing represents a majority of the processes of the Vietnamese textile industry with 1.40×106 tons of textiles being processed (84% of total flows in 2008). T-shirts and trousers were the major products in the textile manufacturing, i.e., produced (64.8%), exported (17.1% and 13.7%, respectively). Thus, these products are ideal candidates for eco-labeling. By filtering indicators through three conditions (availability of data and testing methods, significant environmental impact, and economic feasibility) and validating the identified criteria through a field survey of T-shirt production, we concluded that water and energy consumption, and SO2 and COD emissions could serve as eco-labeling criteria. However, other identified key indicators should be considered for further studies. These criteria are useful for the next steps of criteria development. Material flow analysis and the proposed identification of eco-labeling criteria can resolve the constraints imposed by a lack of data in developing countries.

Keywords: Eco-labeling criteria; key environmental indicators; manufacturer survey; textile flows; Vietnamese textile industry.

V. Hindasageri, H. Ramesh and S.C. Kattimani

Abstract: Ocean wave energy conversion technology is gaining a lot of attention due to its reliability and worldwide availability. This paper presents an experimental study on the performance of the Savonious rotor for utilizing energy from ocean waves moving in circular/elliptical orbits called orbital motion in shallow waters. Three, four and five vaned rotors were considered in this work and their performance under different submergence conditions was studied. The performance parameter selected for study was the rotor RPM. The experiment was carried out in the Wave Flume facility in the Department of Applied Mechanics at NITK Surathkal, India. From the experimental results it was found that the number of vanes on the rotor influences the output rotor RPM. Also, the rotor RPM was influenced by the depth from the still water level at which the rotor was immersed.

Keywords: Ocean wave, rotor motion, renewable energy, Savonious rotor.

P. Peerakiatkhajohn, W. Onreabroy, C. Chawengkijwanich and S. Chiarakorn*

Abstract: This study aims to develop a visible-light responsive thin film for treatment of gaseous pollutants such as Benzene, Toluene, Ethylbenzene and Xylene (BTEX). Silver (Ag) doped titanium dioxide (Ag/TiO2) thin films were synthesized via sol-gel method with different Ag contents. The thin film was formed by dip coating on polyethylene terepthalate (PET) substrate before activating with UV lamp. The X-ray diffractograms demonstrated the heterogeneous phase between anatase crystal of TiO2 and nanosilver. The shift of the wavelength absorption edge to visible light was observed on the composite film due to a decrease of band gap energy. The photocatalytic activity of the thin films was evaluated by the decolorization of 10-5 M methylene blue (MB) dye and the degradation of 25 mg/l gaseous BTEX. The thin film containing Ag/Ti molar ratio as 0.1 exhibited 80% decolorization of methylene blue and 79, 82, 86, 88% degradation of BTEX under visible light, respectively. Thus, the Ag/TiO2 thin film coated on PET substrate can be applied for dye treatment as well as indoor air treatment.

Keywords: BTEX, photocatalysis, silver, titanium dioxide, thin film, visible light.

S.M. Tripathi

Abstract: Nowadays, power crisis term is very common to make us realize that we have deficit amount of electrical energy. On the other hand, ‘misuse of power’ and ‘electricity theft’ are also being heard by everyone. Various articles have been published dealing with electricity theft and how to minimize it. ‘Misuse of power’ is either not in focus or has less priority. To give a clear picture of the present scenario regarding the misuse of power, a thorough study is needed. In this paper, an attempt has been made through a case study to analyze how much power is misused showing the real facts and figures about the current distribution sector of lighting in Lucknow, the capital of Uttar Pradesh (a state in India) and to find out the proper initiatives which might be taken for making the present situation better.

Keywords: Case study, misuse of power, over lighting, power crisis, people in dark.

J. Chotwattanasak and U. Puetpaiboon

Abstract: This study was conducted to evaluate and improve the performance of the existing full-scale anaerobic digester for treating palm oil mill wastewater at Asian Palm Oil Co., Ltd. Krabi, Thailand. Trials were conducted at hydraulic retention times (HRT) of 14, 10, 7 and 6.5 days which correspond to average organic loading rates (OLR) of 2.43, 5.09, 6.50 and 8.70 kg COD/m3d, respectively. Average BOD5 and COD removal efficiency was found to be about 93% and 65%, respectively. Wide variations of influent flow and organic loading were carefully monitored to achieve suitable operation criteria. To ensure suitable and stable biological removal efficiency, pH in the digester should not be less than 7.0 at influent temperatures in the range of 35-45°C. At HRT of seven days, corresponding to OLR 6.50 kg COD/m3d, a specific methane gas generation of 0.35 m3CH4/kgCOD was achieved, with an average CH4 content of 67%. The biogas produced from anaerobic digesters is a cheap source of energy which can be used as a gas engine fuel to produce electricity. Up till now, the biogas plant has generated and sold a total of 7.5 Million kWh of alternative electricity to the Provincial Electricity Authority of Thailand.

Keywords: Anaerobic digester, palm oil mill wastewater, biogas, alternative electricity.