Limitation and separation of domestic solid waste and bio-recyclable organic waste 3- The effect of consecutive fermentation, C: N ratio and rock phosphate enrichment at the recycling of solid organic waste produce organic fertilizers

Abstract

Amount of domestic solid organic waste were collected from some of Erbil city locations, during 2014 for the purpose of recycling it to produce organic fertilizers and estimate the product, two organic waste mixture was prepared from separated waste which collected from the houses in some locations of Erbil city, first mixture with a C: N ratio 1:40, using the organic waste components as they are, second mixture prepared with C: N ratio 30:1 by enriching waste with urea fertilizer. Each mixture will fermented by aerobic and anaerobic methods, after inoculated each of them by 5% of active soil inoculation taken from the surface and soil depth, which was added to the mixtures suit to the fermentation method, a plastic bottles size 25 liters used for a period of 60 days.Then completed with second fermentation stage, using the outputs of fermentation parameters for the first phase (4 treatment), and equipped with two levels of 10% and 20% of the raw rock phosphate (RP), then 8 treatments will fermented with aerobic and anaerobic methods, to become 16 treatment, after being inoculated each of them by 3% of active soil inoculation by using bottles of plastic, according to the fermentation method for the second stage. The important results:Decrease the amount of carbon and increase the nitrogen concentration in the mixtures components after the end of the second fermentation stage , the treatment of aerobic fermentation and 20% RP of the mixture resulting from the anaerobic fermentation of C:N ratio 30:1 in the first fermentation stage interference treatment of 30:1 ratio and anaerobic fermentation recorded highest rate formation of humic and fulvic acid 9.14 and 19.48 g kg-1 sequentially, the lowest rate of phenolic acids formation was 2.95 mg kg-1 with aerobic fermentation method and 30:1 ratio , while the highest rate of formation was 18.64 mg kg-1 with treatment of anaerobic fermentation and 40:1 ratioThe results showed increasing in the total of microbial content, fixing nitrogen and dissolving phosphorus bacteria after the fermentation process, and disappeared of Coliform presence from mixtures with anaerobic fermentation method, and the Salmonella spp. presence disappeared completely in all treatments. Treatment of anaerobic fermentation and 20% RP from mixture C:N ratio 30:1 fermented anaerobically in first stage showed highest rate of available phosphorus concentration 12.93 g P kg-1 , as the treatment given the highest concentration of (DTPA extract ) : 773 , 63.3 , 112, 12 , 32 and 7.3 mg kg-1 of iron , zinc and copper, sequentially .