Study On Mechanism Of Situ-control On The Nitrogen Loss During Aerobic Composting

It was about 30% to 50% of nitrogen loss during aerobic composting and was primary components of effluviums. Situ-decreasing nitrogen loss has important theory and practice significance in improving quality of compost and reducing effluviums releasing. This paper based on the nitrogen loss law during aerobic composting, the effects of nitrogen fixation of different materials were studied as follows:Results of nitrogen fixation tests showed that better materials and dosages were wormcast(7.32%), turf(8.99%), FeCl₃(1.94%), A1C1₃(5.60%), Fe₂(SO₄)₃(5.60%), Al₂(SO₄)3(3.80%), KAl(SO₄)₂(3.80%)and superphosphate(5.60%) respectively. Mixtures of Magnesium hydroxide and Phosphoric acid were significant and the maxium rate of nitrogen fixation reached to 98%.FeCl₃, superphosphate, mixture of FeCl₃ + superphosphate and G₁, G₂, G₃ which were made of Magnesium hydroxide and Phosphoric acid with 1:2, 1:3 and 1:4 proportion, which were all studied on nitrogen fix during laboratory compsting. Results indicated that maxium nitrogen fix rate of superphosphate was 85%, but mixture of FeCl₃ + superphosphate was 62%. Besides, nitrogen fix effects of G₁, G₂ and G₃ were notable, all treatments were reached to more than 65%, and maxium was 95.5% by batches of adding. Fixative of G₁was fit for adding at initial stages, G₂ and G₃ were fit for high temperature period.Studied on Fixztives of mixture of FeCl)3 + superphosphate by 10% + 10%(Treatment A), 15% + 15%(Treatment B) added to initial materials, and G₁(5%), G₂(4.4%), G₃(3.4%) added at initial materials, high temperature stages, fall temperature stages respectively during composting. Which results showed that mixture of FeCl₃ + superphosphate can reduce pH of initial materials, content of total nitrogen enhanced 1.42% and 1.17% according to CK respectively. Furthermore, it was likely to forming composite of organic acid-Fe-P. At the same time, effect of mixtures of Magnesium hydroxide and Phosphoric acid was marked, and content of total nitrogen enhanced 1.45% according to CK. It was obtained that a kind of organic-inorganic compound fertilizer contained Magnesium-ammouim-Phosphate.