Throughout history, farmers have used waste materials to improve soil tilth and fertility. Less industrial development during former times meant fewer industrial wastes available to farmers. In the late 1990s, industry is widespread in Maryland, generating a variety of by-products called residuals. If these residuals possess qualities that benefit soils, they can be land-applied and benefit growing crops. At the Domino Sugar plant the carbonatation process traps microscopic impurities in a chemical reaction that generates crystals of calcium carbonate, or sugar cleaning agent.
Residuals are industrial by-products.
Previously, these by-products were placed in landfills or discharged into the water supply. With the tightening of environmental regulations and limits on Maryland landfill space, land application has become a desirable alternative when the material has a potential benefit to the soil or crops. With constant changes in Maryland industry, residuals vary in type, composition, and quantity. The materials are handled by the responsible industry itself, or by recycling distributors. See Table 1 for a summary of some residuals.