Co-Composing of Municipal Waste and Sawdust for Preservation of Compost Moisture and Preventing Loss of Nitrogen From the Pile

In Zahedan, about 0.8 ton sawdust generates in each day. This sawdust is landfilled despite their good effects on composting process. The aim of the present study was to reuse these serviceable wastes for improving C/N ratio, preventing nitrogen loss from the piles and investigating the effect of sawdust on moisture content of composting piles. Four composting piles were prepared with 0% (blank), 16%, 32% and 70% sawdust admixture. Once sampling was done in each week and samples were analyzed for the C/N ratio, moisture, nitrogen and carbon content. The percent of decrease in moisture content was 33% in blank treatment, whereas this decrease was 15, 15 and 10% for 16, 32 and 70% respectively. Loss of moisture was decreased with sawdust addition and this is very important for arid and hot area because of water sources shortage. The optimum C/N ratio was observed in 16% treatment and loss of nitrogen was decreased with sawdust addition. The percent of decrease in nitrogen content was 30, 7, 7 and 15% for blank, 16, 32 and 70% respectively. The maximum amount of nitrogen in final piles was observed in 16% treatment. Based on experimental data obtained, it can be concluded that sawdust caused water and nitrogen preservation in composting piles and it also improved undesirable and low initial C/N ratio. 16% treatment was shown more desirable effects on composting process and compost quality among other experimental treatments.