Coking wastewater contains various organic matter including polycyclic aromatic hydrocarbons (PAHs), phenolics, benzene and other substances. Phenol is the main component of COD in coking wastewater and the main carbon source for the microbial utilization in biological treatment process. In order to enhanced the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in coking wastewater treatment process, activated sludge was collected from an anaerobic tank of a coking wastewater treatment plant to studied the enhanced biodegradation and kinetics of benzo [a] pyrene (BaP) with phenol, glucose, sodium acetate, TritonX-100, and their combinations as cometabolic substrates, respectively. Moreover, the effects of the mentioned four substrates on the degradation processes of the mixtures of naphthalene, phenanthrene, anthracene, fluoranthene, pyrene and BaP were also investigated. The results showed that the addition of enhanced substrates promote the degradation of BaP and there were significant differences occurred in the degradation rates in the presence of different co-substrates. Sodium acetate demonstrated the highest enhancement of degradation for BaP while 39.9% of BaP can be degraded in 30 days. However, 27.1% of BaP were removed by phenol which was the slowest among the four different substrates; Compared to single substrate group, the combination of phenol and sodium acetate group had the best performance on the biodegradation of BaP and the degradation rate is 50.0%. In different systems, the biodegradation of BaP are followed the first order reaction kinetics model. In the presence of the six PAHs, sodium acetate still had the best enhancement effect, Within 20 days, the biodegradation rates of naphthalene, phenanthrene, anthracene, fluoranthene, pyrene and BaP are 66.1%, 60.7%, 43.2%, 22.0%, 15.5% and 14.7%, respectively. Coking sludge prefer to biodegrade low molecular weight PAHs, such as naphthalene, phenanthrene, anthracene. For high molecular weight PAHs, such as fluoranthene, pyrene and BaP, could be removed relatively less. This study results show that the addition of enhanced substrates had significant promoting effect on PAHs degradation and it is a potential method to realize high efficient biodegradation of PAHs by adding sodium acetate or other substrates in the process of actual coking wastewater treatment.%实际焦化废水中，存在的有机物种类繁多，含有多环芳烃（Polycyclic aromatic hydrocarbons，简称PAHs）、酚类、苯类等物质，苯酚是构成焦化废水COD的主要组成部分，也是生物处理过程中微生物主要利用的碳源。为强化焦化废水处理过程中PAHs的生物降解，采集某焦化废水处理厂厌氧池活性污泥，选择苯酚、葡萄糖、乙酸钠、曲拉通（TritonX-100）及其基质组合作为苯并[a]芘（benzo[a]pyrene，简称BaP）的代谢基质，研究了不同共基质降解组BaP的降解情况及其降解动力学。同时考察了4种易降解基质分别与萘、菲、蒽、荧蒽、芘和BaP 6种混合PAHs的共基质降解。结果表明：加入易降解基质能够促进污泥对BaP的降解，不同基质作用下污泥对BaP的降解率有差异。添加单一基质降解体系下，乙酸钠的促进作用最明显，经过30 d的培养，BaP能被降解39.9%，苯酚促进效果最弱，为27.1%；添加苯酚与另一种易降解基质构成的基质组合相比单一基质对BaP的降解效果更佳，其中苯酚与乙酸钠的基质组合效果最优，其对BaP的降解率为50.0%，各降解体系BaP浓度与时间符合一级反应动力学。6种PAHs存在条件下，乙酸钠组的效率依然最高，在20 d的时间内，萘、菲、蒽、荧蒽、芘和BaP的降解率分别为66.1%、60.7%、43.2%、22.0%、15.5%和14.7%。焦化污泥会优先降解萘、菲、蒽等低分子量PAHs，高分子量如荧蒽、芘和BaP则只有少量降解。研究结果表明，易降解基质对PAHs的降解有明显促进作用，可以利用这种方法在实际焦化废水处理过程中添加乙酸钠等基质，实现废水中PAHs的高效生物降解。
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