Oxygen demand costs

Continuous culture systems of aerobic treatment are likely to be more cost effective since in steady state conditions the respiration rate and hence oxygen requirement, remain constant. This report describes the effects of mean treatment time, treatment temperature and dissolved oxygen level in aerobic continuous culture systems on the removal of odorants from piggery slurry and on the heterotrophic oxygen demand during treatment. 

Molecular connectivity indices are desirable as potential explanatory variables because they can be calculated for a nominal cost (fractions of a second by computer) and they describe fundamental relationships about chemical structure. That Is, they describe how non-hydrogen atoms of a molecule are "connected". Here we are most concerned with the statistical properties of molecular connectivity Indices for a large set of chemicals In TSCA and the presentation of the results of multivariate analyses using these Indices as explanatory variables to understand several properties important to environmental chemists. We will focus on two properties for which we have a relatively large data base (1) biodegradation as measured by the percentage of theoretical 5-day biochemical oxygen demand (B0D)( 11), and (2) n-octanol/water partition coefficient or hereafter termed log P (12). 

At a site in Puerto Rico, a 30-kW Rayox-F (UV/fenton) unit was used in an industrial wastewater application to treat chemical oxygen demand (COD). The unit, which had a flow rate of 1 m /day, had an operating and maintenance cost of 44.32/m (D22279H,... 

Although many of the costs for chemical oxidation technologies will be site specific, chemical costs will generally average 15 to 30% of the total remediation costs. Factors that influence chemical costs will include the chemical oxygen demand (COD) of the contaminated media, pH, the size of the site, and initial contaminant concentrations (D22442A, pp. 19, D-1). 

The capital costs associated with wet oxidation depend on several factors such as capacity of the system, oxygen demand of the wastewater, the properties of the waste to be treated, and the materials of construction of the system. Operating costs of the system are a function of the capacity of the unit, and the external energy requirements. (D16657Y, p. 8.88). 

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