DIRECT DIGITAL-CONTROL OF ENVIRONMENTALLY ISOLATED SEAFOOD MANUFACTURING SYSTEMS

The development of seafood (shrimp) manufacture in the United States i s changing toward increased isolation of the growing-out facilities. S uch a change minimizes a) overhead for discharge permits and pollution abatement costs, b) crop loss by disease and toxic substances from th e environment c) and breaks the seashore umbilical cord. Isolation wil l require increased capital and operating expense. The increased costs must be balanced by reducing operating costs. Three large cost-based factors are operating labor, ration cost and energy cost for pumping a nd environmental control. A portion of the labor and ration costs can be reduced by using direct digital control the environmental and feedi ng subsystems. The shrimp ration must be optimized to provide the grow ing shrimp with the correct balance of nutrients at their current stag e in life. It is necessary to deliver the ration in the correct amount to maintain optimum growth. These criteria require a detailed growth model that relates essential nutritional requirements to size of shrim p. The size and number of the shrimp may be determined by video remote sensing. The dissolved oxygen, salinity and pH are monitored and cont rolled at levels which will not inhibit growth nor inefficiently utili ze ration nutrients. Critical metabolites are monitored and removed fr om the shrimp growout environment to a photosynthetic water recycle un it.