Littlejohns Jennifer V, Daugulis Andrew J
Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada.
Biotechnol Bioeng. 2009 Aug 15;103(6):1077-86. doi: 10.1002/bit.22343.
This investigation characterizes a novel 11 L airlift two-phase partitioning bioreactor (TPPB) for the treatment of gases contaminated with a mixture of benzene, toluene, ethylbenzene, and o-xylene (BTEX). The application of the TPPB technology in an airlift bioreactor configuration provides a novel technology that reduces energy intensity relative to traditional stirred tank TPPB configurations. The addition of a solid second phase of silicone rubber beads (10%, v/v) or of a liquid second phase of silicone oil (10%, v/v) resulted in enhanced performance of the airlift bioreactor relative to the single phase case, with 20% more BTEX being removed from the gas phase during an imposed transient loading. During a 4 h loading step change of three times the nominal loading (60 g m(-3) h(-1)), overall removal efficiencies for the airlift TPPBs containing a liquid or solid phase remained above 75%, whereas the single phase airlift had an overall removal efficiency of 47.1%. The airlift TPPB containing a silicone rubber second phase was further characterized by testing performance during steady-state operation over a range of loadings and inlet gas flow rates in the form of a 3(2) factorial experimental design. Optimal operating conditions that avoid oxygen limitations and that still have a slow enough gas flow rate for sufficient BTEX transfer from the gas phase to the working volume are identified. The novel solid-liquid airlift TPPB reduces energy inputs relative to stirred tank designs while being able to eliminate large amounts of BTEX during both steady-state and fluctuating loading conditions.
本研究对一种新型的11升气升式两相分配生物反应器（TPPB）进行了表征，该反应器用于处理被苯、甲苯、乙苯和邻二甲苯（BTEX）混合物污染的气体。在气升式生物反应器配置中应用TPPB技术提供了一种新技术，相对于传统的搅拌釜TPPB配置，该技术降低了能源强度。添加10%（v/v）的硅橡胶珠固相或10%（v/v）的硅油液相，相对于单相情况，气升式生物反应器的性能得到了增强，在施加瞬态负荷期间，气相中BTEX的去除量增加了20%。在将标称负荷提高三倍（60 g m(-3) h(-1)）的4小时负荷阶跃变化期间，含液相或固相的气升式TPPB的总去除效率保持在75%以上，而单相气升式的总去除效率为47.1%。通过以3(2)析因实验设计的形式在一系列负荷和入口气体流速下测试稳态运行期间的性能，对含硅橡胶第二相的气升式TPPB进行了进一步表征。确定了避免氧气限制且气体流速足够慢以实现BTEX从气相到工作体积充分转移的最佳操作条件。新型固液气升式TPPB相对于搅拌釜设计减少了能源输入，同时能够在稳态和波动负荷条件下消除大量BTEX。
