Composting of washed Ulva reticulata seaweed: process parameter variations and compost quality
Co–composting process of unwashed (Run A) and washed (Run B) seaweed Ulva reticulata with bagasse and broiler litter was studied. Peak temperatures of 48.9°C and 55.2°C were recorded for Runs A and B, respectively. For Run A, the starting wet bulk density was 43.31 kgm–3 and increased by 5.2 times on day 23. Net biodegradable Volatile Solid (VS) reductions were 2.19 and 11.44% for Runs A and B, respectively. Beyond day 37, the respiration rate of both composts had decreased to 8.87 mg CO2.C day–1g–1 VS and 8.09 mg CO2.C day–1g–1 VS (Runs A and B, respectively). Washing treatment lowered the chloride content by 3–5 times in Run B. Final compost from Run B had a better fertilising capacity with its higher N, P and K contents.
Keywords: composting, washing treatment, compost quality, Ulva reticulata seaweed: process parameters, bagasse, broiler litter, chloride content, fertilising capacity