Purification of Pisciculture Waters through Cultivation and Harvesting of Aquatic Biomass

Abstract

The study of thermal wastes from the nuclear plants around Pierrelatte for agricultural, piscicultural, energy and environmental protection purposes resulted in the establishment of a pilot facility as early as 1976. An aquatic macrophyte pilot facility has been operational since 1983 to study the use of water hyacinths from the aspects of energy and ecology. The results obtained suggest that production yields for the 7 month growing period should exceed 60 metric tons (MT) (dry weight) per hectare in a European climate, and that such crops can feasibly be cultivated in temperate regions. The pilot facility is supplied with pisciculture effluent water, making it possible to quantify the stabilization power of the plants. Without primary decantation, with a retention time of 4 days and stabilization with water hyacinths only, the organic matter waste pond surface area required is 3.5 m2/m2 of pisciculture pond. Any primary or secondary facilities will lead to a reduction of these areas. The final decision will depend on the economical optimization of all the wastewater.