Evaluation of the Maturity of the Compost Produced at the Compost Production Site of the NGO ENPRO in Lomé (Togo) Using the UV-Visible Spectroscopy

摘要

Composting is a method of recovery of household solid waste. But to be useful to agriculture the compost resulting from this process must be mature. The objective of this study is to evaluate the maturity of three types of composts produced on the garbage composting unit of the NGO ENPRO in Lomé. Three types of compost (garbage, fruit waste, animal litter) were made in windrows for at least 3 months. The maturity of the composts was determined according to the basic chemical analysis, by UV-Visible spectroscopy. UV-visible spectroscopy performed on the three types of compost at the end of the 3rd and 4th months of composting shows a decrease in the E4/E6 ratio (465 nm/665 nm), Q2/Q6 (280 nm/664 nm) and Q4/Q6 (472 nm/664 nm) for two types of composts characteristic of increasing humification of organic matter. The data from the various elementary analyzes and particularly from UV-Visible spectroscopy show that composts N°1 and N°2 can be considered ripe after 3 months of composting. But the values of the various elementary analyzes clearly show that compost N° 3 is not yet ripe. UV-Visible spectroscopy is a relatively effective method for evaluating the maturity of compost.