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The purpose of this study was to enhance the efficiency of anaerobic co-digestion with sewage sludge using pretreatment technologies and food waste. We studied the effects of various pretreatment methods (thermal, chemical, ultrasonic, and their combination) on hydrogen production and the characteristics of volatile fatty acids (VFAs) using sewage sludge alone and a mixture of sewage sludge and food waste. The pretreatment combination of alkalization and ultrasonication performed best, effecting a high solubilization rate and high hydrogen production (13.8 mL H2/g VSSconsumed). At a food waste:pretreated sewage sludge ratio of 2:1 in the mixture, the peak hydrogen production value was 5.0 L H2/L/d. As the production of hydrogen increased, propionate levels fell but butyrate concentrations rose gradually.

Microbacterium barkeri KCCM 10507 and Paenibacillus amylolyticus KCCM 10508 were isolated and identified for the degradation of polyvinyl alcohol (PVA) contained in textile waste water. Kinetic parameters such as growth rate and substrate utilization rate were determined using a pure culture of two isolated strains. The degradation rate by a mixed culture of two isolated strains was higher than that by single strain only. Also, the effect of polymerization degree on biodegradation was negligible, but initial PVA concentration was very sensitive to biodegradation. Forty-two per cent of PVA and 55% of chemical oxygen demand in textile waste water were removed by a mixed culture of two isolated strains after 5 days.

Dyes, especially from textile industries, are significant pollutants in water and wastewater, which have become pervasive in the environs to which they are discharged. The effluents containing different types of dyes have become ubiquitous in the environment. While several treatment techniques have been developed to address the removal of recalcitrant dyes from water and wastewater, the adsorption technique is highly preferred due to its many advantages. However, selecting the appropriate alternative adsorbents with high adsorption capacity to costly activated carbon has continued to receive great attention. This book chapter reviewed the applicability of adsorptive techniques of agro-waste based adsorbents for the removal of dye pollutants from water and wastewater. The mechanisms of persistent dye pollutant removals based on the adsorption processes were adequately described. Further, the strengths, weaknesses, opportunities and threats (SWOT) of using agro-waste materials as alternative adsorbents are also accounted.

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