| Summary: | 碩士 === 國立高雄第一科技大學 === 環境與安全衛生工程系 === 89 === Over the years it is generally agreed that biological degradation of aqueous wastes is the most economical and efficient means for eliminating pollutants. In the mid-1900’s, suspended growth systems became popular, in which microorganisms were constantly dispersed throughout the wastewater by mechanical and/or air agitation. Recently, fixed film bioreactors（FFR）, in the form, for example, of rotating disks or packed beds, are re-emerging as configurations of great efficiency and stability, especially when a very high degree of degradation is desired. Biological treatment of industrial oil refinery wastewater is a well-established method for remediation of these wastes. We have designed a new bioreactor system to increase the efficiency of biological treatment system by（1）allowing greater organic loads,（2）minimizing production of sludge waste by-product, and（3）increasing process stability and resistance to shock loading.
A fixed film bioreactor system was constructed with a highly porous polyurethane foam to incubate microorganism concentration up to 8,000mg/L.The support frame of bioreactor system was build from cylindrical plastic pall rings to form a packed bed of mixed-media. The frame support provides a high surfaced area-to —volume ratio（210ft2/ft3）,which reduced potential problems of plugging and channeling, distribution of air and water, and mass-transfer limitation.
The studies clearly demonstrated the highly effective nature of this biologically- based fixed film reactor for degrading the pollutions present in the process wastewater stream. Performance data for fixed film bioreactor , COD removal rates were consistently above 80﹪,and at times exceeding 90﹪,at HRT of 8-hours for the pilot system. In addition, all the data received indicated that any phenol present has been completely removed in the FFR system and is below detectable levels. Almost all biodegradation occurred within the first chamber. Therefore , more than 80﹪of COD degradation was consistently achieved with an actual HRT of 2-hours. Furthermore, the pilot system will be expected to decreased the sludge formation and land area usage by 2/3 compared to the traditional technology.
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