Abstract:
Coal gasification stripped gas liquor (CGSGL) wastewater contains large quantities of complex organic and
inorganic pollutants which include phenols, ammonia, hydantoins, furans, indoles, pyridines, phthalates and
other monocyclic and polycyclic nitrogen containing aromatics, oxygen- and sulphur containing heterocyclic
compounds. Most conventional aerobic systems for coal gasification wastewater treatment are not sufficient in
reducing pollutants such as chemical oxygen demand (COD), phenols and ammonia due to the presence of
toxic and inhibitory organic compounds. The current paper reports on the degradation of aromatic compounds
and the reduction of hard COD in CGSGL using a Moving-Bed Biofilm Reactor (MBBR) system. The inoculum
contained a genetically enhanced mixed culture of Pseudomonas putida, Pseudomonas plecoglossicida,
Rhodococcus erythropolis, Rhodococcus qingshengii, Enterobacter cloacae, Enterobacter asburiae strains of
bacteria, seaweed and diatoma. Consistently high hard COD removal (>88 %) and degradation of targeted
phenolic compounds (>93 %) was achieved in the reactor with no loss of biodiversity in the consortium culture.
The performance of the reactor outside the observable range was projected using a Back-Propagation
Artificial Neural Network (BP-ANN) developed in this study.