Impacts of biochar from pyrolysis of agricultural wastes amendment on greenhouse gases emission of soil

• Main Authors: Yu-Chi Chen, 陳昱綺
• Other Authors: Rey-May Liou
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/72095592548588537247

碩士 === 嘉南藥理大學 === 環境工程與科學系 === 102 === Biochar was a solid byproduct derived from pyrolysis of biomass in low or absence of oxygen, high organic carbon content, porous, alkaline,highly capability of desorption, multiple-use materials. Recent attention has been given to biochar as a soil amendment because of its potential soil conditioning properties and benefits to physico-chemical characteristics,slow-release carrier for fertilizer and carbon sequestrating agent. This carbon sequestration benefits result from the fact that biochar takes carbon from the atmosphere-biosphere pool and transfers it to a slower cycling form that has the potential to exist for hundreds to thousands of years, and improve the soil physical-chemical properties and activity of microbes, soil fertility, and delay nutrient release of fertilizer, as well as reduce nutrient losses from fertilizer and soil, and alleviate soil pollution. The multiple-functional technology was the thermal conversion of biomass wastes into biochar which was used to agriculture. However, further studies should be given to many issues about biochar. Various pyrolysis process (including fast, slow and gasification pyrolysis) of biomass can yield different chacteristics (physical-chemical properties, pore structure, sorption capacity of pollutant) of biochars. The biochars prepared with different pyrolysis process will be characterized by scanning electron microscope(SEM), X-ray diffraction (XRD), and analysis of BET surface area. The results showed that carbon storage of biochar from pyrolysis of bagasse, pyrolysis temperature was the important factor to effect the properties of biochar. Higher pyrolysis temperature would increase the micropore development and surface area of biochar. Effects of biochars produced from pyrolysis of rice husk and bagasse under different temperature.amendment on soil properties, carbon sequestration, and CO2 emission were examined using a laboratory incubation approach. Three levels of raw material/biochar (0, 2.5, 5 wt%) were added into three different series of soil (Cf, Cc and Si soils) and all samples were incubated at room temperature for 56 days. The pH, electrical conductivity(EC), organic carbon content were analyzed during incubation. The results showed that biochar amendment increased soil pH of Cc and Si soils significantly. Amendment of biochar from higher pyrolysis temperatures (500 and 800 ℃) would increase soil organic carbon after 56-day incubation. In the initial stage (14-28 days) of incubation, amendment of rice husk and bagasse (no pyrolysis) would increase CO2 emission significantly in Cf soil.