化工制药工艺残渣燃烧过程固氯研究

Immobilization of chlorine during combustion of chemical residues

采用管式固定床反应器对化工制药工艺残渣的燃烧分解进行了实验研究,进一步通过加入氧化钙/碳酸钙来防止燃烧过程残渣中氯的释放。实验结果表明,残渣在燃烧时氯主要以氯化氢形式排出,加入固氯剂后能有效地抑制氯化氢的生成,且固氯效果随着钙化物投加量的增加而明显提高。当氧化钙/残渣比(质量比)达到0.8时,固氯率可达97%以上;当碳酸钙/残渣比(质量比)提高到2.0时,固氯率为76%。与此对应的Ca/Cl摩尔比分别为30和40。继续增加钙投加量,固氯效果基本不变。同时发现添加一定量的木屑在助燃的同时有助于提高固氯效果。

A study on chlorine immobilization during combustion of a pharmaceutical waste （chemical residue containing 1.12% of Cl by weight, heating value = 3 631 kJ/kg） was performed using a fixed bed tubular reactor. The experimental results show that most chlorine in the waste residue was converted to HCl during the combustion. Release of HCl. was significantly inhibited by the addition of CaO or CaCO3 in the feed to capture the HCl （to form CaCl2）. The best dechlorination performance was achieved at a combustion temperature 〈700 ℃ ;a higher temperature would result in more release of HCl from decomposition of CaCl2. CaO was a more effective additive capturing 〉 97% of HCl at a CaO/residue of 0.8 （Ca/Cl molar ratio of 30） vs. 2〉76 % captured at a CaCO3/residue of 2.0 （Ca/ Cl molar ratio of 40）. No substantial increase in HCl capture was observed at a still higher dose of CaO or CaCO3. Adding a quantity of wooden waste （heating value = 7 091 kJ/kg） increased the overall heating value and enhanced the HCl capture.