Combination Uses of Boiler Ash and Palm Oil Mill Sludge with Animal Manures in Compost Production

Abstract

In Thailand, intensive agriculture and longtime chemical fertilizer use cause in low soil fertility and organic matter. Organic fertilizer can increase soil organic matter and improves soil properties. In southern part of Thailand, oil palm cultivation is popular. High amount of organic waste was generated after the oil palm extraction process. This study interested in the use of boiler ash and palm oil sludge with manures (cattle manure, chicken manure and pig manure) and LDD.1 addition for compost production. This experiment was arranged in Factorial in Completely Randomized Design with 3 replications and 2 factors; firstly, type of wastes comprised of boiler ash and palm oil sludge, and secondly, type of manures comprised of cattle manure, chicken manure and pig manure. The composting process took 45 days. The change of pH, plant nutrients, sodium content, electrical conductivity (EC), organic matter, organic carbon, C:N ratio, moisture content and Germination Index (GI) in the composts were determined. The results showed that type of wastes and type of manures had significant effects on pH, total nitrogen, total potassium and sodium content, but not effect on EC, total phosphorus, organic matter, organic carbon, C:N ratio, moisture content and GI. From the study, treatment consisting of palm oil sludge 26.7 kg with pig manure 6.7 kg was the most suitable treatment for composting. Its compost had pH 6.64 (neutral), 2.53 dS/m EC, 2.91% total nitrogen, 3.37% total phosphorus, 0.88% total potassium, 0.03% sodium content, 35.15% organic matter, 20.39% organic carbon, 7:1 C:N ratio, 51.95% moisture content and 82.2% GI. The compost was completely degraded and can be used as organic fertilizer after 45 days of composting process.