Study On Microwave Pyrolysis Of Bamboo Residues And Properties Of Its Products

To solve the problem caused by energy crisis and environmental pollution, the exploitation and utilization of biomass energy has been paid more attentions during these years. The paper described the character of biomass energy and its technology of application, regarded that biomass quickly pyrolysis is as a significant technology. Through summing up the research situation current of preparing bio-oil by pyrolysis biomass in detail, reviewing different kinds of typical pyrolysis sets and their characteristics, microwave pyrolysis is thought that is one of new technologies for bio-oil manufacture, which can effectively used in biomass pyrolysis because of various advantages (like fast efficient, energy-saving, selective, non-polluting and easy control etc.) of microwave calefaction. Bamboo is our one of important forest resources, but its utilization was much lower. The experimental research was conducted by using bamboo residues on a laboratory designed pyrolysis system, in which a microwave oven was adopted as the main body.Based on the research of bamboo residues microwave pyrolysis experiments, obtained the influence rule of main parameter such as material moisture, pyrolysis temperature, pyrolysis power, particle size, catalyzer and charcoal amount etc. on the microwave pyrolysis products. Thermo-gravimetric analysis of bamboo residues was studied; the results showed that the microwave pyrolysis of bamboo residues was a complex dynamic process, including traces of weightlessness, pyrolysis of cellulose and hemicellulose and pyrolysis of lignin three stages. Using "Universal Design rotating center portfolio" optimized the bio-oil preparation technology from bamboo residues microwave pyrolysis, optimal parameter that pyrolysis power of 800W, temperature of 492℃, charcoal amount of 4.2% (wt.% bamboo residues), and pyrolysis time of 13min was achieved. Then the result was also validated that can obtain 52.80% of bio-oil yields.Physical properties (ash content, water content, viscidity, density, pH value, residue rate and acid number) and components of bio-oil from the experiment were analyzed with precision apparatus nowadays. The results showed that bio-oil had complex components, high oxygen content and high water content, and bio-oil was acid with strong causticity and poor stability, therefore, bio-oil needed to further modified to be better utilized.The bamboo charcoal yield of bamboo residues pyrolysis was above 20%, and the characteristic of charcoal was analyzed. It can be seen from the FTIR spectra that the surface structure of bamboo charcoal increased part oxygen/nitrogen groups, enhanced adsorption after catalysed with reagent, and thus changed the bamboo charcoal's selective adsorption on organics and inorganics. Therefore bamboo charcoal activations with different reagents were also studied in this paper. Under the conditions of that KOH concentration of 25%, soaking time of 24h, microwave power of 800W, and activation time of 7min, the activated bamboo charcoal could obtained that iodine adsorption value was 1239.08 mg·g^-1, methylene blue adsorption value was 274.95 mg·g^-1, and the specific surface area was 1394.16 m²Â·g^-1, of which adsorption index was exceeded the level specified for the first grade in GB/T 13803.2-1999 standard.On the basis of the properties analysis of bamboo residues microwave pyrolysis products, the prospect of products was also summarized.