Experimental study of vermicompost drying process

Abstract

Biohumus is widely used for various vegetable productions. However, its use is difficult in places such as recreation, sports, golf, and football fields. Humus uneven distribution across the field promotes grass growth at different speeds. The result is not acceptable. Therefore, to develop vermicomposting end product usability work is needed in several directions. One of the directions is to develop the possibility of humus evenly spreading across the field. It can be done developing new or improving the existing technologies, which allow doing it with minimal impact on product quality. Granular vermicompost can be called concentrated fertilizer, because the recycling process reduces the volume of material more than 10 times, due to water removal and material thickening while extruding. It is therefore necessary to examine the humus moisture content and determine the energy needed for drying it. Given that vermicompost is a biologically active material, the drying must be carried out at the lowest possible temperature. It is not recommended to increase the drying temperature above 35 °C. The aim of this research is to determine the drying rates of vermicompost in different temperatures of the drying agent and avoid overdrying. The drying rate is defined as the variation of the moisture content with respect to the time. The studies showed that the maximum of the drying speed was observed at the beginning of the process and reached 0.86 %-min-1 in the drying temperature 64 °C. Decreasing of the drying temperature decreases the drying speed to 0.59 %-min-1.