Abstract
Soft biomass such as weeds from urban areas and levee slopes harvested with a high-moisture content are not normally suitable for recycling. But if this soft biomass is dehydrated, it can be used as solid fuel. In order to dehydrate and recycle high-moisture soft biomass, we tested a composting dehydration technique currently used to compost animal wastes. In this study, we conducted weed composting experiments using small- and medium-scale composting reactors (volume: 14 L and 431 L). We investigated the effect of moisture content on thermogenic properties in the early stages of composting; we also investigated the effect that adding seeding compost had on composting characteristics such as thermogenic properties and decomposition rate of organic matter. When the moisture content of the weed was less than 30 %w.b., there was very little rise in temperature and the heat production rate of the weed was low. Therefore, it was not possible to dehydrate the weed to a moisture content of less than 30 %w.b.. The rise in weed temperature during composting occurred earlier when seeding compost was added than when it was not added, and then adding seeding compost accelerated the decomposition rate of organic matter. Adding seeding compost is therefore effective in facilitating and accelerating composting dehydration of soft biomass materials.
