南方硬木化学浆漂白废水污染特性及特征污染物

Pollution feature and characteristic pollutants of bleaching effluent of southern hardwood chemical pulp

采用常规分析、红外光谱、紫外光谱、色谱、质谱等技术,分析、研究了南方硬木化学浆漂白废水的污染特性和特征污染物。结果表明,废水中含有较高浓度的溶解态有机物,可生物处理性较差,且废水存在大量的发色基团和助色基团,使废水色度很深;废水的有机物结构中含有苯环、羰基、羟基、醚基和羧基等基团,羰基是重要的发色团,羟基、醚基和羧基均是助色基团,羰基可能与苯环上的碳碳双键形成共轭,加深废水的色度;废水成分非常复杂,主要有机污染物包括酯类、苯酚类、烷烃类和有机酸类物质,芳香族化合物的峰面积相对含量为58.16%。根据废水中检测到的主要有机污染物对发光细菌的半数发光抑制率EC50,废水中主要控制的特征污染物应包括苯酚类物质、氯酚类有机物、有机氯化物和邻苯二甲酸酯类物质。

Pollution feature and characteristic pollutants of bleaching effluent of southern hardwood chemical pulp were investigated by using the data obtained from conventional analysis,infrared（IR） and ultraviolet（UV） spectrum,gas chromatography（GC）-mass spectrometry（MS）.It was found that in the effluent the concentration of dissolved organic compounds is high and its biodegradability bad,CODCr（dissolved chemical oxygen demand） and BOD5（dissolved biochemical oxygen demand） 1.5 kg·m-3 and 0.4 kg·m-3 respectively,and BOD5/CODCr 0.27.The data from IR and UV spectra indicates that the organic pollutant structures in the effluent contain benzene ring,carbonyls that are chromophore groups,and hydroxyls,ethers and carboxyls which are auxochromous groups.The deep color of effluent can be attributed to these compounds containing these groups as well as conjugation structures between carbonyl groups and CC double bonds.An analysis for the data from of GC-MS shows that there are a large number of complicated organic pollutants in the effluent,including lipoid substances,phenols,alkanes and organic acids,aromatic compounds,and their relative peak area is up 58.16%.Based on photobacterium EC50 of the major organic compounds measured,the characteristic pollutants to be controlled for bleaching effluent of southern hardwood chemical pulp should include phenols,chlorophenols,organic chlorides and phthalates.