Fate of contaminants during treatment of H‐coal process wastewaters

Abstract

and a culture adapted to leachate. The build-up of butyrate indicates a breakdown of other, larger organic species in the leachate. This was not observed when a similar experiment was performed using a culture selected for volatile fatty acid degradation. Apparently, the organisms responsible for the formation of butyrate from higher compounds are not present in this culture.Inhibition of methane occurs when the leachate adapted culture is dosed with leachate, presumably because of sulfate reducers. This problem could be eliminated by removing the sulfuric acid step from the pretreatment scheme or selecting a culture from a seed that does not contain sulfate reducers. The rate controlling step is probably acetate removal, hence the formation of methane. This is typical of anaerobic digestion systems [ I ] . Current research is using higher concentrations of leachate to study the effects on the microbial population. The degradation of other compounds in the leachate is being studied also.The ultimate fate of the components present in the process wastewaters produced by coal liquefaction and gasification facilities is of interest to those developing effective treatment strategies. Conversion processes generate wastewaters containing relatively high concentrations of phenol, ammonia, cyanide, and hydrogen sulfide, as well as other organic and inorganic compounds [ I ] . These components are not unique to coal conversion process Reference i n this report to a n y specific commercial product. process, or aervice IS to facilitate understanding and doel not necessarily imply Its endorsement or favoring b y the United States Departnrent of Energy. 26February , 1985 wastewaters and are also found in various combinations in wastewaters of the petroleum, steel, and chemical process industries, among others. The bulk of the contaminants must be removed from the wastewater prior to reuse or discharge to the environment. aper reports the results of a treatability study of H-Coal Yiquefaction process wastewater. Previous investigations have demonstrated the applicability of conventional treatment technology in controlling the wastewater from gasification and li uefaction pilot plants [2, 3, 41. It can be concluded from &es, earlier studies that no single treatment operation is capable of reducing all of the This

Catalytic Wet Oxidation of Phenol: Kinetics of the Mineralization Rate

“…Among these harmful compounds, phenol and phenolic substances have warranted more attention in the field of industrial wastewaters in the past two decades, because of their toxicity and the frequency of industrial processes producing waters contaminated by phenol. − Moreover, phenol is considered to be an intermediate product in the oxidation pathway of higher-molecular-weight aromatic hydrocarbons; thus, it is usually taken as a model compound for advanced wastewater treatments.…”