Abstract
Coal-biomass briquettes (BBs), which are composed of low-grade coal, biomass, and a sulfur fixation agent, emit less sulfur dioxide (SO2) during combustion than low-grade coal; thus, BBs are a good manufactured product for use as a domestic and light industrial fuel in rural areas subject to acid rain in China. Combustion ash of BBs (BB ash) is usable as an amelioration agent for acidic soil because it has high alkalinity. In this study, growth experiments were conducted to estimate the effects of the addition of BB ash to acidified soil on the growth of certain crop plants and on the amounts of metals in plant tissue samples. The dry weight and length of plants were increased by the addition of BB ash to the soil, suggesting that plant growth was promoted because BB ash both neutralized acidified soil and contained much calcium, a plant nutrient. In addition, the addition of the BB ash inhibited the leaching of some phytotoxic metals (aluminum and manganese) from the BB ash and acidified soil and also inhibited the adsorption of the metals by plants. These results suggest that BB ash is suitable as an amelioration agent for acidic agricultural soils.
