The economics of waste water--Aquaculture systems

Due to recent environmental legislation and growing scarcities of popular sea- foods, there is considerable interest in innovative systems that can strip nutrients biologically from waste water and produce potentially useful materials. While many variations of such systems exist, the systems described here are based on the secondary sewage-marine aquaculture system developed at the Woods Hole Oceanographic Institution with an option of using thermal effluent as a heat source. The design, performance and resulting costs of operational systems for commercial production scaled up by factors of ten,100 and 1,000 are projected and compared. The largest of these systems would be able to handle the waste water from a city of 100,000 people. Despite uncertainties in the systems, our analysis shows that large-scale systems using sewage as a nutrient source and free heat from power plant effluent (or located in a warm climate) could be profitable.