污泥与煤共热解过程中磷元素的挥发规律研究

污泥灰分中磷元素含量明显高于煤,其中主要的晶体态含磷化合物为磷酸铁钙和少量的磷酸铝。利用高频加热反应装置考察了污泥-神府煤混合物快速热解过程中磷元素挥发规律。结果表明,污泥-神府煤混合物热解后磷元素主要存在于热解焦中。磷元素挥发比例随污泥添加比例的增加先升高后降低,随热解温度的升高而增加。热解温度不高于1 100 ℃时,混合物中以有机磷的挥发为主,磷元素挥发比例不高于3.2%。热解温度高于1 200 ℃后无机磷中磷元素挥发明显,1 300 ℃下最高有33.0%的磷元素随热解气体挥发出。

Volatilization of phosphorus during co-pyrolysis of sewage sludge and coal

The phosphorus content of sewage sludge ash is higher than that of Shenfu coal, and its main phosphoric crystalline minerals are calcium iron phosphate and a certain amount of aluminum phosphate. The volatilization of phosphorus during co-pyrolysis of sewage sludge and Shenfu coal was studied with a high frequency furnace reactor in laboratory scale. It has been found that after pyrolysis most of the phosphorus in fuels is deposited in char. The volatilization ratio of phosphorus increases at first and then decreases with the increase of sewage sludge ratio in fuels. And it monotonically increases with the pyrolysis temperature. Organophosphorus compounds make up the main part of volatized phosphorus when pyrolysis temperature is less than 1 100 ℃ and its volatilization ratio is lower than 3.2%. Inorganic phosphorus does not volatilize obviously until 1 200 ℃, and the highest volatilization ratio of phosphorus is 33.0% at 1 300 ℃.