Automation of the wastewater reception process for fish protein production
Authors: Topon-Visarrea Blanca , Moran Andrés , Valle Mauricio 
Published: April 2022

The food industry generates a high impact on the environment due to the waste generated in the production process and the different products that go on the market. A large part of them is used in landfills or as agricultural fertilizer, but they are not efficiently used. Each sector generates different percentages of waste depending on what is manufactured. One of the sectors that has grown the most is aquaculture and fishing, generating more and more waste which negatively impacts the environment. Ecuador, due to its oceanographic location is one of the main exporters of fishery products in Latin America, highlighting tuna fishing. The waste generated in this sector can be utilized to improve the functional properties of food providing with antioxidants. Reusing that waste will give rise to cheaper products with high nutritional values. Some of the subproducts that can be obtained are flour, protein, oil, hydrolysates, concentrates, animal feed, among others. Industries that produce fish protein are globally growing. This product is used as animal feed in all countries. Among the main producers of fish protein are Peru and Chile. In Ecuador, only one company is manufacturer. This company was born because of a need for environmental remediation of the tuna sector, currently reaching a production of 2400TM / year, with working long hours and double shifts. This company seeks to improve the current production process, incorporating an automatic control system in the processing of raw materials. The production of fish protein consists of five main stages: reception, centrifuge, filtration, evaporation, and drying. For the final product elaboration, wastewater from the manufacture of canned tuna is used, which is the main raw material. The reception stage is one of the most delicate parts of the process since the raw material has a time of use of up to 36 hours. After this time, the product cannot be used. This phase requires improvements since it has an operational type level which is the lowest level of the automation pyramid. This stage is limited to basic mechanical level controls. At the reception, the raw material must pass through a separator of suspended solids until the filtration process using membranes for the water treatment where dissolved solids are extracted. Through a change of pressures, the passage of water is forced through the membranes. Subsequently, the evaporation and drying phases take place to obtain the final product. In the present research, an automatic control system is designed to monitor the time, temperature, and volumes in the reception stage. It will generate a controlled and constant shipment of raw material complying with the installed capacity of 2400 tons of finished product per year. This amount is obtained with no extra days of the staff, optimizing resources. The proposed automatic process helps to maintain a constant pumping system. Finally, 95% of efficiency will be obtained in the process, decreasing the production time from 10.15 hours to 9.30 hours.