EVALUATING THE VERMICAST PRODUCED FROM ORGANIC MUNICIPAL WASTE OF DUHOK CITY WITH BULKING AGENTS USING EISENIA FOETIDA EARTHWORMS

This work was took place at the laboratories of the College of Agricultural Engineering Sciences at the University of Duhok, during September 2022 - May 2023, to investigate the compost quality (CQ) produced at Kwashe Recycling Municipal Waste Factory (KRMSWF), and the effect of vermicomposting technique on composting organic municipal solid waste (OMSW), reducing time of composting, and improving the vermicast quality by Eisenia foetida earthworms, using different types and rates of bulking agents (Cow dung, wheat straw, vegetable litters and OMSW). The result showed that incorporating bulking agents of vegetable litters with OMSW and their rates in preparation the vermicomposting beds, were significantly influences on the physical traits (color, odor, water holding capacity, bulk density and porosity) of the produced vermicast and reduced the time of vermicomposting by (Eisenia foetida) at (P < 0.05). Also, significantly influenced on the properties of the produced vermicompost. the pH value of the produced vermicast increased by mixing vegetable litters and OMSW with Cow dung and wheat straw in (T4, T5, and T6) to (8.23 ±0.023, 8.25±0.012, and 8.27±0.000) respectively, in comparing with their values in (T1 and T2), with pH (6.81±0.061, and 5.43±0.057) respectively. In general, the CEC Cmolc. Kg-1 %, ash%, TOC%, OM%, TN%, and TP% were increased in comparison with compost and vermicompost produced in (T1, T2 and T3). While the EC value, TK%, and TNa% decreased in comparison with their values in (T1, T2, and T3). The C:N ratio in all treatments decreased with the exception of the % C:N ratio in T6, which increased in comparison with (T2, T3, T4, and T5). The lowest account of total heterotrophic bacteria (THB) in the produced compost and vermicompost were found to be (195×105 ± 0.88) CFUg-1 in T3, and (279×104±9.17) CFUg-1 inT6, while their higher number was recorded in T5 (298×106±15.7) CFU g-1. The highest and lowest total Coliforms and (E. Coli) bacteria were (≥1600) CFU g-1), exceeded the permissible number (1000 CFU g-1) for all treatments.