I would also like to know just as Endashaw Workie

Life cycle assessment

The unit cost of pollutant removal is largely determined by the kind of pollution and by the conversion process.

EUR/kgCOD is indeed a good key performance indicator (KPI) for mainly organic wastewaters. However if 90% or more of this COD is converted to biomethane (CH4) instead of only carbondioxide (CO2), then this cost gets negative when the renewable biomethane is used to replace non-renewable fossil fuels. In other words the investment in this kind of COD conversion is paid back by the savings in fossil fuel (and shrinking of the climate footprint) as proven at full-scale over the last 40 years.

The price of the reagents used;

the cost of the wastewater treatment structure; the quantity of COD/BOD to be removed (USD/kg COD removed)

  the treatment stage: primary, secondary, tertiary

The cost of wastewater treatment depends on the water outputs resulting from these processes, the extent to which the pollutants are removed, and to what purpose this water will be used. By assessing these points, we can estimate the treatment cost

As above, it is very dependent on the compounds requiring treatment, the standards they are treated to, the selected process(es), and resulting desired outcomes.

It also depends on the size of the wastewater treatment plant and the treatment system

Specify. Dependent on country

Wastewater treatment depends on the volume of wastewater, treatment procedures, reagents used and other related factors.

You can use LCA to check the suitability of your treatment technology if you know the costs of all components used for WW treatment viz. chemicals, energy, estimated manpower expenditures etc.

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Article Environmental and economic feasibility study of a total wast...