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Moringa oleifera is an herbal galactagogue that is used to increase the volume of breast milk. The objective of this study was to evaluate the efficacy of Moringa oleifera leaves in increasing the volume of breast milk in early postpartum mothers.A randomized, double-blinded, placebo-controlled trial was conducted. Eighty-eight postpartum women were randomized to either the study group receiving oral Moringa oleifera capsules or to the control group receiving oral placebo capsules.There was no difference in median breast milk volume on the third day of postpartum between the Moringa oleifera leaf group and the control group (73.5 vs 50 ml, p = 0.19). However, the amount of breast milk in the Moringa oleifera group was 47% more than the one in the control group. The exclusive breastfeeding rate at 6 months in this study was 52.3% in the Moringa oleifera group, which met the goals set by the World Health Organization.Even 900 mg/day of the Moringa oleifera leaf could not significantly increase breast milk volume in early postpartum mothers, but the amount of breast milk in the Moringa oleifera group was 47% more than the one in the control group. The exclusive breastfeeding rate at 6 months in the Moringa oleifera group achieved the goals set by the WHO. Therefore, Moringa oleifera leaf may be used as a galactagogue herb to increase the volume of breast milk.

A novel gas-pressurized (GP) torrefaction method to produce torrefied biomass with high fuel quality was recently proposed in our previous work. The pyrolysis behavior and kinetics of the GP torrefied biomasses were studied in detail using DAEM, FWO and Friedman methods, and the reaction mechanism was also investigated in this work. The results showed that the Friedman method was most suitable for the pyrolysis kinetic of the torrefied biomass, compared to the DAEM and FWO methods. The pyrolysis activation energy of the GP torrefied biomass at volatilization stage was lower than those of the raw biomass and torrefied biomass produced via traditional torrefaction. Contrastingly, it increased significantly at char decomposition stage. The mechanism investigation showed that the reasons for the low activation energy at volatilization stage were the catalytic effect of the minerals, such as K and Na, and the porous structure of the GP torrefied biomass. On the other hand, the significant increase of the activation energy at char decomposition stage was mainly attributed to two factors. The first factor is that some minerals, such as SiO2, suppressed the decomposition of the char. The minerals having catalytic effect, such as K and Na, had already volatilized at high temperatures. Another contributing factor is the high aromaticity of the GP torrefied biomass. This research provides a deep understanding of the pyrolysis kinetics and mechanism of GP torrefied biomass.

Torrefaction is an efficient way for the biomass dewatering and upgrading before its thermal conversion and utilization. In this work, a gas-pressurized (GP) torrefaction method was proposed to torrefy the biomass wastes. The effect of gas pressure on biomass torrefaction was studied and the reaction mechanism was investigated in detail. The results indicated that the GP torrefied biomass had lower volatile matter content and higher carbon content than the torrefied biomass obtained by traditional method with carrier gas under atmospheric pressure (AP). The high heating values of GP torrefied rice straw and sawdust at 250 °C were as high as 17.9 MJ/Kg and 24.5 MJ/Kg, much higher than those of AP torrefied rice straw and sawdust which were13.6 MJ/Kg and 19.2 MJ/kg, respectively. The GP torrefaction at 250 °C removed as high as 77.88% and 66.68% of oxygen in rice straw and sawdust, respectively. Furthermore, it converted part of the volatile matter into fixed carbon through promoting aromatization reactions. The GP torrefied biomasses had richer pores and higher specific surface area than the AP torrefied biomasses. This can increase the reactivity for subsequent thermal conversion of the torrefied biomass. It was also found that the gas pressure significantly promoted the thermal decomposition of the hemicellulose and cellulose. The main difference of the reaction mechanism between the GP torrefaction and AP torrefaction was the secondary reactions between the volatiles and biomass. It was because the volatiles were not removed timely during GP torrefaction. Furthermore, the pressure was essential for effectively promoting the secondary reactions.

The accurate characterization of droplet evaporation requires measurement of both the size variation (evaporation rate) and the temperature/composition evolution. To obtain the evaporation rate of moving droplets, a nanometer diameter change must be quantified on droplets of several dozens of microns, moving at a few meters per second. This paper used an innovative optical technique, 1D Global Rainbow Technique, to characterize locally the evaporation of gasoline droplets by measuring the droplet evaporation rate and refractive index (i.e. temperature and composition). The information on the refractive index and the droplet size are extracted from the angular rainbow position and from the rainbow shape, respectively, while the evaporation rate is extracted from the ripple structure angular shift.

The study in this paper makes an assessment of the bioenergy potential from crop residues, forest residues, livestock waste, semi-arid areas energy crops, municipal solid waste (MSW) and water hyacinth in Zambia. A total technical bioenergy potential of about 310 PJ per annum has been estimated and using quantum geographical information systems (QGIS) the spatial distribution shown. Of the total, crop residues contributes 64%, forest residues 17%, livestock waste 9%, jatropha cultivation in semi-arid lands 8% and 2% from MSW and water hyacinth together. Formulation of an integrative bioenergy policy, creation of a bioenergy resource database, conducting of research and development, creation bioenergy unit, engagement and involvement of all stakeholders, education and capacity building, feedstock value chain analysis, dissemination of information, creation of decentralized models, devolution of powers and financing models are very critical aspects if the bioenergy sector has to be sustainably adopted in Zambia.

Sugarcane is one of the most promising sources of green energy for a major sugar producing country like Thailand. Any efforts to improve energy efficiency in sugar industry would result for green energy production and more avoided GHG emissions. This paper assesses the potentials for energy saving and GHG emission reduction in sugar production in Thailand. It is found that there is a wide gap between the most efficient mills and the less efficient ones among the country’s 47 mills, with specific steam consumption ranging from 400 to 646 kg steam/ton cane. Thus significant potential exists for energy saving and GHG emission reduction in many mills, using some of the 17 commonly common technologies/measures identified. For the nine mills studied, which could have resulted in a combined saving savings of 23–32% of the total mill energy consumption, further savings of 5–14% could be achieved.

Assessment among various groove-gasket designs under solid oxide fuel cell operating condition is presented. The gasket is deformable under the stress applied by external loading between 0.13–0.67 MPa. The operating temperature is from 30 to 800 °C. It has an indicated width of 1.95 mm and depth of 2.1 mm., which is accommodated in a square, triangular and U groove channel having the dimension of 2.0 × 2.0 mm 2 . From the results, the U shape configuration provides the best performance with immeasurable leak rate under the applying load represented in term of global stress of 0.67 MPa. A stress analysis using Finite Element Method (FEM) tool, ABAQUS™, suggests sufficiently high compressive stress far exceeding the elastic limit with enough coverage of such high-stress area for U-shape design. In contrast, those from square and triangular designs posses relatively lower well-distributed stress and smaller region of highly concentrated stress, respectively. The associated deformed cross section suggests that the gasket has plastically deformed toward the U-shape wall surface at a greater degree than those for triangular-shape design. It can be concluded that the greater region in deformed gasket surface can more effectively reduce interconnectivity of micro channel on the interface between the gasket and the interconnector surfaces.

Torrefaction is the thermal treatment techniques performed at relatively low temperature (< 300 °C) in an inert atmosphere, which aims to improve the fuel properties attractively. In this study, woody biomass (Leucaena leucocephala) was torrefied at various temperatures and holding times and the pyrolysis behaviors of the torrefied wood was examined in detail by using TG­MS technique. It was found that the carbon content and the calorific value of the torrefied leucaena increased significantly when increase the temperature and holding time during the torrefaction. From the TG­MS analysis, the pyrolysis behaviors of the torrefied leucaena were significantly different from that of the raw leucaena. The char yield at 800 oC for the torrefied leucaena was increased when increasing the holding time during the torrefaction. On the other hand, the tar yield during the pyrolysis decreased significantly with the increase in the holding time during the torrefaction. Through the results from the TG­MS analysis, it was concluded that the structure of leucaena was changed by the torrefaction at temperature below 275 oC and the cross­linking reactions occurred during the pyrolysis resulting in increase in char yields and decrease in tar yields. It was also suggested that the longer the holding time during the torrefaction, the more the cross­linking reactions proceed during the pyrolysis. The results obtained from the study provide the basic information for the pyrolyser and/or gasifier design by using torrefied biomass as a fuel., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1991-1994

A thermal performance of impinging flames of widely-used cooker-top burners depends on a complex interaction between flow field and combustion. The critical situation is placed on two typical cooker-top burners having almost the same configurations, but yielding about 10% point difference in thermal efficiency. Therefore, in situ flame measurements of averaged velocity using particle image velocimetry (PIV) and image of averaged OH radicals using planar laser-induced fluorescence (OH-PLIF) are required to obtain insight into the coupling mechanisms during the combustion and heat transfer, and to develop a comprehensive experimental data base to support a phenomenological understanding of the differences in flames of the two burners. A combined study of flow field and combustion forms the basis of a much better understanding of the casual links that couple fluid mechanics, combustion and heat transfer in the two burners. This can provide guidelines for efficient burner design to meet future regulatory requirements.

Co-firing investigation of a high-moisture-content municipal solid waste (MSW) with Thai lignite have been performed in a laboratory-scale fluidised bed to study the effects of MSW moisture content on the combustion and emission characteristics of major gaseous pollutants. In this study the comparison of 35%- and 60%-moisture MSWs were tested. The results show that the bed temperature in the case of 35%-moisture content is higher than for in case of 60%-moisture content due to the difference of physical properties of the fuel. The combustion efficiency for the case of 35%-moisture MSW is higher than that for 60%-moisture MSW due to higher bed temperature at lower waste moisture content. The synergistic effect of the co-firing of lignite with MSW reduces the emission of CO leading to increase in combustion efficiency. CO concentration for the case of 35%-moisture content is generally lower, and is much less sensitive to the level of excess air. Both the concentration values of SO2 and the fuel-S converted are lower for lower moisture content waste, particularly at high mass fraction of waste. The fuel mixture with low-moisture in waste gives higher fuel-N conversion to NO whereas the fuel-N conversion to N2O is higher for higher moisture content waste, particularly at high excess air.

The use of palm oil as a base stock for an environmentally friendly lubricant for small four-stroke motorcycle engines is investigated. Palm oil was blended with mineral oil at different compositions to the viscosity requirement of commercial lubricant. A liquid additive package was added to improve the viscosity of the lubricant. A blend that meets the viscosity requirement was then chosen for physical and chemical property characterization and subjected to an engine test. The blend consists of 50.6% (wt.) palm oil, 41.6% mineral oil, and 7.8% additive package. The properties evaluated include viscosity, viscosity index, flash point, foaming characteristics, and wear scar. The engine performance and emission tests were carried out with a 125-cc motorcycle on a chassis dynamometer using a Bangkok Driving Cycle. Compared to a mineral-based commercial oil, the palm oil-based lubricant exhibits superior tribological properties, but offers no clear advantage on engine and emission performance.

Cooker-top burners are used extensively in Thailand because of the rapid combustion and high heating-rates created by an impinging flame, which is characteristic of these types of burners. High thermal efficiency with low level of CO emissions is the most important performance criteria for these burners. The wide variation in reported performances of the burners appears to be due to the ad hoc knowledge gained through trial and error of the local manufacturers rather than sound scientific principles. This is extremely undesirable in view of safety, energy conservation and environmental protection. In the present work, a nationwide cooker-top burner performance survey and an implementation of a PIV technique to analyze the burner performance as well as advising local manufacturers were carried out. Experimental data were reported for the base line value of thermal efficiency of all the burners. The thermal performance parameters and dynamic properties of the flow field at a flame impingement area, i.e. velocity magnitude, turbulent intensity, vorticity and strain rate were also reported as a function of burner type, which was categorized into four types based on the configuration of the burner head: radial flow burners, swirling flow burners, vertical flow burners and porous radiant burners.

This work deals with the development of mathematical techniques for incorporating existing sulfation models into a CFD code for simulation of the flow and heat and mass transfer in multi-phase reacting flow; i.e. in the combustion of pulverized coal with the dry type sulfur absorption process. By compromising the ability to maintain some features of the sulfation, as suggested in literatures with computation time, the model was successfully embedded into FAFNIR, a CFD code by Lockwood et al. and has been used for prediction of SO2 absorption in pulverized coal combustion to compare with experimental data at various conditions. This paper focuses on mathematical representation of the sulfation process by including the effects of temperature on the reaction rate at zero sulfation and during increased sulfate loading or accumulation of product layers. The model is relatively simple and is applicable over a wide range of temperatures, particle sizes and SO2 concentrations. Validation was performed and it was found that the model satisfactorily represents the amount of accumulated sulfate within the entire domain of calculation.

Experiments have been performed to investigate the effects of primary chamber preheating temperature and batch size of the waste feed on the combustion of medical waste in a two chamber controlled air incinerator of 50 kg/h nominal capacity. The primary purpose is to determine qualitatively the functional relationships between the key incinerator performance indicators and the above two parameters so that optimum preheating conditions of a pilot incinerator, which has been in trial use at a hospital, may be defined. Three batch sizes were used, namely: 5, 7.5 and 10 kg, with the primary chamber preheating temperature varied from 500 to 800 � C at 100 � C intervals for each batch. The secondary chamber temperature control was set at 900 � C. The results showed that increasing the waste charging temperature and the weight of charge tend to accelerate the rate of volatile gas release, causing a ‘‘bottleneck effect’’ in the secondary chamber and, hence, a negative effect on the overall performance of the incinerator, as reflected in the residual unburned CO in the gases leaving the chamber. Higher charging rates could have been achieved by increasing the combustion air supplied to the chambers. Using CO measurement as a criterion for good combustion makes it possible to determine the optimum incinerator temperature control settings and operating conditions, as well as to assure continuous, efficient, environmentally satisfactory operation. The optimum operating condition for the range of experiments tested appears to be a batch size of 5 kg and a primary chamber preheating temperature in the vicinity of 700 � C. � 2005 Elsevier Ltd. All rights reserved.

Co-combustion of high moisture municipal solid waste (MSW) and high sulfur Thai lignite in a laboratory scale bubbling fluidized bed has been investigated. This paper presents the effects of the mass fraction of a model MSW in the fuel mixture, as against 100% lignite, on the combustion characteristics that may be inferred from temperature distributions, carbon combustion efficiency and CO and CO 2 concentrations and on the emissions of major gaseous pollutants, including CO, SO 2 , NO and N 2 O. The influence of excess air and secondary air on those characteristics are also discussed. The results show that within the 40% MSW fraction tested, co-combustion is characterized by enhanced combustion of volatiles in the freeboard, a lower bed temperature and a combustion efficiency drop of up to 8%. Co-combustion either increases or reduces CO emission depending on the percentage of excess air. Reduction of up to 7–18% of SO 2 is observed at the 40% MSW fraction for the range of excess air and secondary air tested. Both NO and N 2 O increase slightly with increasing fraction of MSW. Within the range of experimental conditions tested, the optimum condition for co-combustion in view of combustion efficiency and CO, NO and N 2 O emissions is: 20% MSW, 40% excess air and 0.2 secondary to total ratio, although the reduction of SO 2 is slightly smaller than at other conditions.

The combustion of three high moisture content waste materials in a fluidised bed combustor has been investigated and a comparison with co-firing of these materials with coal in the same combustor has been made. Waste materials burnt were olive oil waste, municipal solid waste and potato, which is representative of vegetable waste. Mixtures of up to 20% mass concentration water in the waste were fed to the combustor. Above that value the moisture content was too high to sustain combustion without addition of coal. Measurements of CO, NOx, SO2 temperatures were made and the carbon combustion efficiency evaluated. Co-firing with coal resulted in markedly higher combustion efficiencies with an increase of approximately 10–80% when burning the simulated MSW. However, this was much lower than the value of 93% when coal was burnt on its own. It was also much lower than the value obtained, average 90%, when co-firing potato and olive oil waste with coal and there was little difference in the combustion efficiency between the two types of waste and with increasing moisture content. It was concluded that the high ash content of the simulated MSW 26%, compared with 5% in the other two waste materials resulted in slower burning and consequently the char particles were elutriated from the bed without being fully burnt. In term of gaseous emissions during co-combustion, CO emission is relatively insensitive to change in waste fraction. While emission of SO2 can be reduced as the waste fraction increases as a result of fuel-S dilution. But in terms of percent fuel-S converted, it is actually increased by increasing waste fraction. Emissions of NO and N2O increase slightly with MSW fraction.