Reaktörde Kompostlaştırma: II. Çim Kırpıntıları

Abstract

In the present study, in-vessel aerobic composting was evaluated in terms of impact on stabilization of grass clippings (GC). The composting period was 22 days. The temperature, carbon (C), total Kjeldahl nitrogen (TKN), C/N ratio, cellulose, volatile solids (VS), moisture, pH, electrical conductivity (EC), total coliform (TC), fecal coliform (FC), heavy metals and radioactivity were investigated and the kinetics of degradation of organic matter was found during composting. The reaction rate constant of degradation of VS was found as 0.0372 day - 1 (R 2 = 0.99). The VS decreased from 88.78 % to 83.51 % at the end of the process. The GC reached maximum temperature of 62°C within 1 day. C decreased from 49.32 % to 46.39 % while TKN decreased from 2.94 to 2.69 %. C/N ratio that was 16.78 at the beginning increased to 17.25. Cellulose increased after 22 days. pH inc- reased from 5.97 to 8.26 and EC decreased from 1006 to 942 S/cm. Coliforms decreased during composting. The obtained composts contained heavy metals under the standards related to heavy metal. At the end of the composting process α-radioactivity greatly decreased and also the β-radioactivity decreased. 40 K and 137 Cs con- centrations were also determined. In-vessel aerobic composting was effective to reduce TC, FC, α-and β- radioactivity in GC used. According to these parameters, if such composts are used in soil, a risk for human health could not arise.