有机化学实验室废液焚烧NO_x、SO_2和HCl的排放特性

NO_x,SO_2 and HCl Emissions of Organic Waste Liquid from Chemistry Laboratory Incinerated in Fluidized Bed

在内径120mm、高2m的流化床中焚烧处理有机化学实验室废液,研究在800～950℃烟气中氧浓度在0～1200范围内NOx、SO2以及HCl的排放特性.结果表明,废液中有机胺类化合物及微量硝酸在焚烧过程中产生NOx,其浓度最大值约130mg/m3.试验中发现950℃下NOx浓度低于900℃时的值,说明胺类有机物在950℃下还原NOx能力比900℃下强烈.焚烧过程中产生的SO2来源于有机硫化物及微量硫酸的分解,结果表明氧浓度接近零时SO2浓度最高,在此条件下温度越高,SO2浓度越高,但随着氧浓度的增加,SO2浓度迅速下降.HCl主要来源于有机氯化物的分解,在800～950℃下HCl浓度基本相同,说明有机氯基本上转化为HCl.

Waste liquid discharged from organic chemistry laboratory has lots of toxic substances, including organic-nitrogen, sulfur and chlorine compounds. Chemical oxygen demand (COD) values are in the range of 30 × 104-150 × 104 mg/L. Incineration is adopted to treating it in a fluidized bed of 2 m in height and 120 mm in diameter, to investigate NOx, SO2 and HCl emissions at 800-950°C. Experiments show that NOx mainly comes from the oxidation of organic-amine and decomposition of minim HNO3, and the maximum NOx emission reaches about 130 mg/m3. It is found NOx, emission at 950°C is lower than that at 900°C, because at 950°C the amine-compounds, such as aniline and methyl aniline in waste liquid, have stronger reducing effect on NOx than that at 900°C. SO2 from the oxidation of organic-sulfur and decomposition of minim H2SO4, which decreases very rapidly with the increase of oxygen concentration in flue gas. SO2 emission reaches the maximum at zero percent of oxygen, when it increases very rapidly with the increase of temperature at low oxygen concentration at 800-950°C, This result is probably related to the decomposition of H2SO2. HCl emission is mainly from organic-chlorine, and it is almost the same at 800-950°C, indicating organic-chlorine is almost totally converted to HCl.