Evaluation of the effect of cocopeat in continuous thermophilic composting (CTC) of kitchen waste

Abstract

Effective waste management is important in reducing the negative environmental impact caused by urbanization, industrialization, and population growth. Like most other developing countries, less attention is paid to waste treatment in Sri Lanka, while the focus is mainly on waste collection. Most municipalities of Sri Lanka practice the collection of kitchen waste (KW) separately at the household level but the collected KW mainly end up in a neglected composting yard and no further steps were taken to utilize KW in producing value-added product/s [1]. The conversion of biodegradable waste into compost has been practiced worldwide for decades now [2]. However, the production and application of composting has two major problems, longer processing time, and nutrient status dependency on the method of composting and on the composition of the initial substrates used. Over the years, many solutions have been proposed for these issues [3, 4]. One simple efficient method to accelerate the composting process is Continuous Thermophilic Composting (CTC) in which the waste is incubated in moderately high temperatures, synthetically creating the thermophilic composting phase throughout the process. According to literature, CTC can reduce the composting cycle of KW to 14 days while a regular cycle can be last up to 60 days [3]. However, the drawback of artificially accelerated composting processes is the lowered quality or maturity of the product. Cocopeat is abundantly available in Sri Lanka for a low cost. As a bulking agent in composting, cocopeat increases the porosity of the substrate thereby promotes the aeration, while its high water-holding capacity supports to maintain optimal moisture content. The addition of cocopeat promotes microbial growth and accelerates the aerobic digestion of substrates. The current study proves that the integrated thermophilic composting process with cocopeat as an additive valorizes KW into high-quality compost via a rapid and economically feasible route.