湿热水解处理餐厨垃圾氮素转化规律

为了研究餐厨垃圾湿热水解过程中氮素的变化规律，设计了10、30、60、90和120℃5个温度水平以及30、60、90、120、150和180min6个加热时间水平，进行了30组完全实验，对不同湿热条件下餐厨垃圾粗蛋白、TN、NH4＋-N、NO3-N、有机氮及氨基酸等氮的不同存在形式的变化规律进行实验研究。结果表明，10、30及60℃条件下蛋白质的高级结构不会改变，利于粗蛋白的积累，且在温度120℃，加热时间90min条件下粗蛋白百分含量最高，占干物质的31．34％；随温度的升高和加热时间的延长TN、NHf-N和有机氮含量均上升；当温度达到120℃，由于水解反应，各温度处理下NHf．N浓度超过有机氮浓度，而NO3-N始终维持较低水平。氨基酸总量随温度的升高和水解时间的延长呈上升趋势，当温度达90％，加热时间达180min时，处理后餐厨垃圾总氨基酸百分含量最高，达164％，但温度达到120℃时，随着处理时间的延长，餐厨垃圾总氨基酸含量明显降低。

Rule of nitrogen transformation in hydrothermal process for treatment of restaurant wastes

In order to study the nitrogen forms transformation of restaurant garbage during hydrothermal process treatment, 30 testing groups were selected and trials were conducted under temperature levels of 10, 30, 60, 90, 120℃ and heating intervals of 30, 60, 90, 120, 150, 180 rain. The experiment is to analyze the varia- tion of forms of nitrogen such as crude protein, TN, NH4＋-N, NO3-N, organic nitrogen and amino acid. The re- sults shows that the advanced protein secondary structure did not change its form under temperature condition of 10, 30 and 60℃ in which it benefit the accumulation of crude protein. The optimal crude protein content of the treated waste was obtained at 120℃ after 90 minutes heating and the crude protein content was 31.34%. As temperature and heating interval increase, the contents of TN, NH4 -N and organic nitrogen increase. When the temperature reaches 120℃, the content of NH4＋-N exceeds that of organic nitrogen due to hydrolysis reaction. However, nitrate content has remained at a low level. When the temperature and heating interval are adjusted to be 90℃ and 80 minutes respectively, the percentage content of total amino acid reaches 164%, which is the highest during the hydrothermal process, however, it begins to decline significantly as the treatment time extends after the temperature reaches 120℃.