A methodology to quantify the aerobic and anaerobic sludge digestion performance for nutrient recycling in Aquaponics

Abstract

Description of the subject. This research note presents a methodology to quantify the tilapia sludge digestion performance in aerobic and anaerobic reactors for aquaponic purpose. Both organic reduction and macro-and microelements mineralization performances were addressed. Objectives. To set up an appropriate methodology to quantify sludge digestion performance in aquaponics. To describe the methodology and illustrate it with some results as example. Method. Equations were adapted to quantify (1) the organic reduction performance in terms of chemical oxygen demand (COD) and total suspended solids (TSS) reduction, and (2) the nutrient recycling performance in terms of macro-and microelements mineralization. Results. The equations were applied to data obtained from experimental aerobic and anaerobic reactors as example. Reactors were able to remove at least 50% of the TSS and COD input. The nutrient mineralization was consistent with a 10 – 60% range for all macro-and micronutrients. Conclusions. The methodology provides explicit indicators on the sludge treatment performances for aquaponics. Treating aquaponic sludge onsite is promising to avoid sludge spillage, improve nutrient recycling and save water.