Calculate the dose of diminishing return

dose_of_diminishing_returns(
  dose,
  DOC_final,
  molar_mass = 297,
  threshold = 0.3/10
)

dose_for_criterion(dose, DOC_final, criterion)

Arguments

dose: The coagulant metal concentration (Al3+ or Fe3+) in mmol/L.
DOC_final: The final DOC concentration, probably modeled using fit_edwards_optim() or fit_edwards() and coagulate_grid().
molar_mass: The moalr mass of the coagulant, in grams per mol Al or Fe.
threshold: The point of diminishing return threshold, in mg/L DOC per mg/L dose. Often this is taken to be 0.3 mg/L DOC per 10 mg/L dose (Brantby 2016).
criterion: A desired final DOC concentration in mg/L

Value

The dose (in mmol/L) of diminishing returns.

References

Bratby, J. 2016. Coagulation and Flocculation in Water and Wastewater Treatment. IWA Publishing. https://books.google.ca/books?id=PabQDAAAQBAJ

Examples

dose_curve <- coagulate_grid(fit_edwards("Low DOC"), DOC = 4, UV254 = 0.2, pH = 5.5)
dose_of_diminishing_returns(dose_curve$dose, dose_curve$DOC_final)
#> [1] 0.08960449
dose_for_criterion(dose_curve$dose, dose_curve$DOC_final, criterion = 3)
#> [1] 0.03415216