Pemanfaatan limbah padat industri karet remah (crumb rubber) untuk pembuatan kompos

The objective of the research was to create a compost formula for plant fertilizer. Composts containing 100, 90, 80, 70, 60, and 50 parts of crumb rubber industry solid waste and 10, 20, 30, 40, and 50 parts of bran were prepared. The mixing was done by adding 20 ml of molasses and 20 ml of EM4. Moisture content was maintained at 40-60%. The compost was mature in 40 days. The resulting compost was compared to SNI 2803:2010 Solid NPK Fertilizer and Regulation of the Minister of Agriculture No. 70/Permentan/SR-140/10/2011 on Organic Fertilizer. The best compost that met the requirements (except kalium) was the compost with 20 parts of bran, 80, 90, and 100 parts of solid waste. The physical properties of the compost were dark brown similar to the color of the soil, insoluble in water, C/N ratio of 20.74 to 25.44, temperature approximately equal to the ambient, and odorless.