Industrial wastewater

    Industrial wastewaters can be simply defined as wastewater discharged from industrial and commercial sources [1].

    Besides conventional inorganic pollutants, they may also contain some toxic organic compounds such as polychlorinated biphenyls(PCBs) and persistent organic pollutants(POPs) detected in many major industries. With closer regard to the effluent of one of the major industries, pulp and paper industry, its typical content include about 500 different chlorinated organic compounds and absorbable organic halogens(AOX)[2].

    Due to the toxicity, mobility and loading of industrial pollutants, industrial wastewater may potentially do more harm to water resources, human health and the environment than the actual volume of wastewater[2].

Halogenated organics

    Halogenated organics or organohalides are organic compounds to which have halogen atoms covalently attached.

    Their physical and chemical properties vary greatly depending on their molecular structures and weight, type of halogenation and the number of halogen atoms. In general, the more complex, the heavier, the more halogen atoms, the more toxic and the poorer biodegradability these organohalides are.

    Over the recent years, emerging reports and studies have gradually shown their adverse impact on human health and ecosystems. However, in addition to their wide distribution in the production process, their acute toxicity and poor biodegradability also make them one of the most troublesome pollutants in industrial wastewater treatment. Safe, efficient and economical solutions are urgently needed to deal with them.

Industrial wastewater treatment

    Industrial wastewater treatment covers the mechanisms and processes used to treat industrial wastewater.

    According to the latest World Water Development Report, the ratios of treated municipal and industrial wastewater to untreated differ greatly in the light of different-level-income countries. And globally, it's commonly estimated that over 80% of all wastewater is discharged without treatment[2].

    Different types of contamination of wastewater require a variety of strategies to remove the contamination. Here we focus on the organic ones. Concerning to the remaining organic recalcitrants, conventional processes including chemical precipitation and membrane filtration have some disadvantages, e.g. high plant operation, maintenance cost and accumulation of concentrated sludge and their disposal problems. Advanced treatment methods and specialized microbial strains are needed to be employed for the removal of those persistent organic recalcitrant[3].

References