The ultimate goal of the proposed project is to convert some major fibrous agricultural residues including cereal straws into raw materials for cement-based panel systems. Our approach relies on: (a) vigorous reactions of carbon dioxide gas with cement paste to mitigate the inhibiting effects of lignocellulosic residues on the hydration of cement; (b) reduced alkalinity of CO2-cured cement-based matrices to mitigate the potential for alkali attack on lignocellulosic residues; and (c) fine geometry of residues such as straw to enhance dimensional stability of cement-bonded residue board under moisture and weathering effects. The proposed Phase I research will: (1) characterize major fibrous agricultural residues based on their composition, physical attributes, compatibility with the hydration of cement, processability, alkali resistance, and dimensional stability; (2) establish processing conditions for accelerate CO2 curing of cement-bonded boards with different fibrous residues; (3) assess the competitive technical position of cement-bonded fibrous residues, emphasizing their durability and dimensional stability under weathering effects; and (4) determine the commercial viability of converting fibrous agricultural residues into raw materials for the production of cement-bonded boards. Our approach is based on a successful exploratory work conducted by DPD, Inc. which indicated that wheat straw, in spite of its strong inhibitory effects and incompatibility with conventional processing techniques, can yield CO2-cured cement-bonded boards of high mechanical performance, durability and dimensional stability.
Anticipated Results/Potential Commercial Applications of Research: The proposed technology converts fibrous agricultural residues into valuable raw materials for the production of high-performance cement-bonded boards suiting siding, roofing, backerboard and other building applications. This technology provides a sustainable source of raw materials, in an era of shrinking wood supplies, for meeting the growing needs for high-performance building panels.
