ABSTRACT
Innovative and cost-effective waste treatment and resource recovery methods are needed to reduce the environmental degradation associated with liquid waste streams from municipalities, industries, and agricultural enterprises. Artificial wetland systems that use aquatic macrophytes have been developed to treat liquid wastes with a minimum of capital and energy input. However, there have been limited efforts to recover useful products from these aquatic systems. This chapter demonstrates the potential of aquatic plants to remove pollutants from wastewater and produce useful crops. Demonstrations were conducted at Cypress Creek Sewage Treatment Plant, Florence, Alabama. Two types of earthen facilities were built: five units to demonstrate sludge as plant fertilizer in soil flooded with secondary effluent and four units to conduct flow-through demonstrations. Aquatic plants can recover nutrients from wet sludge (3.5% solids), and sludge is at least as effective as inorganic fertilizer for aquatic plant production.
