Effects of compost quality from non-dairy creamer sewage sludge-solid compost biogas-rice husk char on bok choy mustard (Brassica rapa L.)

Abstract

Non-dairy creamer sewage sludge (NDCSS) has high organic matter and nutrients for compost production but NDCSS has a problem for the composting process because it has high moisture and slurry form. Therefore, the composting process of NDCSS requires mixing of other organic materials such as solid compost biogas (SCB) and rice husk char (RHC). Therefore, this study aims to determine the chemical properties of compost from a mixture combination of NDCSS, SCB, and RHC, and to assess compost quality as organic fertilizer from a mixture combination of NDCSS, SCB, and RHC through growth and yield of bok choy mustard (Brassica rapa L). Experiments were carried out in greenhouses from March to September 2019. The research treatment consisted of 7 treatments mixture combination of NDCSS, SCB, and RHC for the composting process, and each treatment was repeated 4 times. The composting process is carried out by anaerobic or fermentation methods. The research layout was used as a randomized complete block design (RCBD). The NDCSS can produce compost with the highest N content, while the RHC will produce compost with the highest P. The mixture combination of NDCSS, SCB, RHC, and the mixture combination of SCB and RC will produce compost with the highest K content. Compost from NDCSS produces the best organic fertilizer because it is able to make the best biomass wet weight and dry weight of bok choy mustard biomass.