Study On The Utilization Of Algae And Soybean Straw

During the process of energy resources utilization, the fossil energy would producedisastrous influence on the energy security because of the limit reserve, environmentalpollution of the fossil fuels, also, they are non-renewable. It urges the researchers both hereand abroad to seek the alternative energy. The biomass energy is rich, renewable, widespreadand oligosaprobic. It is acknowledged as the most promising alternative energy of fossil fuel.Thus, researching the energy utilization of biomass has important function in reliving theenergy crisis and improving the environment.The sea area of our country is vast, and the algae production occupies first place in theworld. Also, as the large agricultural country, the agricultural residue, straw yields are so high,and the soybean straw has large proportion in the straws. So, it is representative to choose thealgae and soybean straw as the research subject.This paper used drying oven, tube furnace, microwave oven, thermal gravimetricanalyzer and ash fusibility tester as the experimental apparatus. Taked thesoybean straw andthe algae as the materials. Investigating their pyrolysis and combustions characteristics toprovide fundamental and research basis for the energy production process of algae andsoybean straw.The drying experiments were investigated about the influence of different initial watercontents, contents of desiccants and drying temperature of algae and soybean straw on thedrying characteristics. It was found that, the lower initial water contents, the higher dryingrate. Compared the60%with the15%initial water content, the drying time per unit algae was3.83times higher, and the drying time per unit soybean straw was5.53times higher. Whenthe contents of desiccants was10%and15%, respectively. The drying time per unit algae was1.96times as the pure algae. When the drying temperature was100℃,110℃and120℃,respectively. The average drying rate of algae was9.20%,47.71%and61.97%higher than90℃, and the average drying rate of soybean straw was11.90%,51.19%and153.74%higherthan90℃. The activation energy of algae drying algae was smaller than soybean straw drying,and the algae was easier to be dried.The pyrolysis experiment of soybean straw was investigated about the influence ofpyrolysis temperature, material particle size, and metal oxide as catalyst on the pyrolysis ofsoybean straw which was the material of the experiment, including the influence on theformation characteristics of its flammable gas (CO，H2) and ultimate weight loss rate. It was found out that the flammable gas yield and ultimate weight loss rate increased as pyrolysistemperature increasing, and soybean straw’s particle size did not show much influence onpyrolysis because of high pyrolysis temperature, the ultimate weight loss rate remained atabout93%. In addition, using metal oxide Al2O3, Fe2O3, Ni2O3and CaO as catalysts topyrolyse soybean straw can improve flammable gas production but reduce ultimate weightloss rate，the biggest reduction rate can reach to9.84%.The pyrolysis experiment of algae was to investigate the influence of differentmicrowave powers, metal oxides and metal salts onto the pyrolysis of algae. It was found thatthe heating rate and the final temperature would increase as enhancing the microwave power.When microwave power increased from750W to2250W, the yield of solid residue decreasedby22.05%, and gas yield increased39.45%. After adding5%CuO and MgO, the yield ofsolid residue and bio-oil appeared the greatest decreasing ranges of14.35%and11.04%,respectively. Electrical energy consumption increased by1.44%and reduced by40.76%afterCuO and MgO was added, separately. When algae was mixed with5%MgCl2, ZnCl2andNaH2PO3, respectively, the yield of solid residue increased by3.98%,1.13%and2.31%, andthe bio-oil yield increased by6.3%,16.92%and0.71%, respectively. The effect of microwaveabsorption was ZnCl2> NaH2PO3> MgCl2.The thermal gravimetric analyzer was used to research the combustions characteristics ofalgae and soybean straw under different mixing ratios(0:100,15:85,30:70,45:55and100:0).It was found that overflow rate of volatile was higher than the combustion rate of fixed carbon.When adding more algae, the kindling temperature was smaller, and the maximum differencewas11.99%, the burnout temperature was higher, and the maximum amplitude was32.27%.The volume of ash taper reduced as the temperature rose. In the meantime, the ash tapershrinked and expanded time and again, especially during the hemispherical fusiontemperature and the yield temperature.