SYNOPSISBagasse is a solid waste that remains after crushing sugarcane. Since bagasse is used as a fuel in sugar mills, characterization of its thermal degradation is rather important in order to use it efficiently. Thermal analysis of bagasse was carried out using differential thermal analysis (DTA) and thermogravimetry (TG) under oxidizing and inert atmospheres. Kinetic studies were based on weight loss obtained from T G analysis. Thermal degradation of bagasse takes place in two stages: volatilization and carbonization. The reaction rate, activation energy, entropy change, enthalpy change, and Gibbs free energy for the two thermal stages were calculated. The results indicated that activation energy for the volatilization stage is higher than that of decarbonization stage, and that both the rate constant and activation energy for combustion are higher than those of pyrolysis.

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The objective of the present work is to investigate the pyrolysis of sugarcane bagasse in a semi-batch reactor and study the effect of process parameters of pyrolysis on the products yield to determine optimum parameters for maximum bio-oil production. Parameters of the pyrolysis process such as temperature, particle size of sugarcane bagasse and flow rate of nitrogen (N2) have been varied as 350–600 °C, 0.25–2 mm and 100–500 cm3/min, respectively. According to the various pyrolysis conditions applied in the experimental studies, the obtained oil, char and gas yields ranged between 38 and 45 wt%, 24 and 36 wt%, and 23 and 37 wt%, respectively. The maximum pyrolysis bio-oil yield of 45 wt% was achieved at temperature of 500 °C, particle size of 0.5 -1 mm with nitrogen(N2) flow rate of 200 cm3/min. Based on the results captured under this study's pyrolysis conditions, temperature is considered to be the most important parameter for product distribution. As the increases of the pyrolysis temperature the bio-char yield decreased and increase of gas yield. The bio-oil yield increases with increasing the temperature, reaches a maximum value at about 500 °C and reduces thereafter at higher temperature is expect due to secondary cracking reactions of the volatiles, which results produce a higher gaseous yield.

The effect of temperature on the electrical parameters of photovoltaic cells is negative. The efficiency of photovoltaic cells can be enhanced by cooling which the temperature is considered as one of the main factors that affect negatively on the output power. This study was carried out to compare between three different cooling techniques and determine their effects on the output power. The first, cooling techniques is applied, the panel front surface cooled using the water spray on the surface. The second, the panel back surface cooled by extended fins. The third, the panel back surface cooled by extended fins with fans. As expected, the results of comparisons different methods using in cell cooling showed that, there is an increase in the efficiency of photovoltaic cells with the drop in cell temperature, which helps to increase the rate of photovoltaic cell performance and output power. In these experiments the output power increased 2.5 %. At the first technique using water spray method the temperature dropped 7 degrees. At the other two methods the temperature dropped 3 degrees less than the panel without cooling. The used pump and fans were power consuming. So, the most effective method was cooling using the fins.

Direct Water Injection (DWI) is commonly used in many nitrogen oxides (NOx) emissions control applications due to its effect to reduce the adiabatic flame temperature. In this paper an experimental test rig is designed to study the effect of water injection spray inside a simulated gas turbine combustor from the gas fuel. The practical work introduced by the chemical reaction methodology followed by the experiment which was presented and discussed carefully. Results are obtained in term of the exhaust gas temperature and different injection parameters including position, direction and fuel mass flow rate on the nitrogen oxide emission value in PPM (Parts per Million) at different conditions. The results showed that the best water injection effect was obtained at 45° degree inside the primary air zone. Injection location has a major effect on the NOx reduction as the best injected location is the Primary air zone compared with the direct fuel nozzle tip due to the increase of the water droplets residence time inside the combustor and perform a vortex that will affect the reduction of exhaust gas temperature and NOx emission respectively. The huge impact was observed at LPG (Liquefied Petroleum gas) flowrate 2.7L/min and water to fuel ratio about 0.4 as the NOx value was decreased about 73% from almost 381 PPM to 73 PPM. The chemical reaction arrangement order methodology presented good agreement with the experimental results at different fuel flow rate and equivalence ratio. The chemical Reaction equations were implemented to calculate the different adiabatic flame temperatures which is experimentally known as the exhaust gas temperature and impacted directly the NOx emission results.