Removing phenol from coal gas wastewater by ozone-immobilized biological activated carbon

When engineering bacteria that can effectively degrade phenol are immobilized on activated carbon, immobilized biological activated carbon (IBAC) comes into being. A combinatorial process of ozone and IBAC is applied in treating coal gas wastewater. Under the condition that the ozone dose is 18 mg/L and the ozone oxidation time is 20 min, the oxidation contributes little to the removal of total organic carbon (TOC), while it changes the characteristics and the structure of the organic substance in the wastewater. Making use of ozone-IBAC treatment, when the inflow contains 500 mg/L COD and 95 mg/L phenol, their removal rates are higher than 80% and 92%. After 6 months of operation, the engineering bacteria density keeps above 6.1 × 10³ cfu/g carbon and in dominant status, moreover, the engineering bacteria distribute uniformly on the activated carbon. The long-term steady viability and high biodegradation efficiency of the engineering bacteria are discussed in terms of the theory of ecological place.