tidywater (version 0.10.0)

chemdose_toc: Determine TOC removal from coagulation

Description

This function applies the Edwards (1997) model to a water created by define_water to determine coagulated DOC. Model assumes all particulate TOC is removed; therefore TOC = DOC in output. Coagulated UVA is from U.S. EPA (2001) equation 5-80. Note that the models rely on pH of coagulation. If only raw water pH is known, utilize chemdose_ph first. For a single water use chemdose_toc; for a dataframe use chemdose_toc_df. Use pluck_cols = TRUE to get values from the output water as new dataframe columns. For most arguments in the _df helper "use_col" default looks for a column of the same name in the dataframe. The argument can be specified directly in the function instead or an unquoted column name can be provided.

Usage

chemdose_toc(
  water,
  alum = 0,
  ferricchloride = 0,
  ferricsulfate = 0,
  coeff = "Alum",
  caoh2 = 0
)
chemdose_toc_df(
  df,
  input_water = "defined",
  output_water = "coagulated",
  pluck_cols = FALSE,
  water_prefix = TRUE,
  alum = "use_col",
  ferricchloride = "use_col",
  ferricsulfate = "use_col",
  caoh2 = "use_col",
  coeff = "use_col"
)

Value

chemdose_toc returns a single water class object with an updated DOC, TOC, and UV254 concentration.

chemdose_toc_df returns a data frame containing a water class column with updated DOC, TOC, and UV254 concentrations. Optionally, it also adds columns for each of those slots individually.

Arguments

water

Source water object of class "water" created by define_water. Water must include ph, doc, and uv254

alum

Amount of hydrated aluminum sulfate added in mg/L: Al2(SO4)3*14H2O + 6HCO3 -> 2Al(OH)3(am) +3SO4 + 14H2O + 6CO2

ferricchloride

Amount of ferric chloride added in mg/L: FeCl3 + 3HCO3 -> Fe(OH)3(am) + 3Cl + 3CO2

ferricsulfate

Amount of ferric sulfate added in mg/L: Fe2(SO4)3*8.8H2O + 6HCO3 -> 2Fe(OH)3(am) + 3SO4 + 8.8H2O + 6CO2

coeff

String specifying the Edwards coefficients to be used from "Alum", "Ferric", "General Alum", "General Ferric", or "Low DOC" or data frame of coefficients, which must include: k1, k2, x1, x2, x3, b

caoh2

Option to add caoh2 in mg/L to soften the water. Will predict DOC, TOC, UV254 using a modified equation (see reference list). Defaults to zero.

df

a data frame containing a water class column, which has already been computed using define_water_df. The df may include a column named for the coagulant being dosed, and a column named for the set of coefficients to use.

input_water

name of the column of water class data to be used as the input for this function. Default is "defined".

output_water

name of the output column storing updated water class object. Default is "coagulated".

pluck_cols

Extract water slots modified by the function (doc, toc, uv254) into new numeric columns for easy access. Default to FALSE.

water_prefix

Append the output_water name to the start of the plucked columns. Default is TRUE.

See Also

chemdose_ph

Examples

water <- define_water(ph = 7, temp = 25, alk = 100, toc = 3.7, doc = 3.5, uv254 = .1)
dosed_water <- chemdose_ph(water, alum = 30) %>%
  chemdose_toc(alum = 30, coeff = "Alum")

dosed_water <- chemdose_ph(water, alum = 10, h2so4 = 10) %>%
  chemdose_toc(alum = 10, coeff = data.frame(
    x1 = 280, x2 = -73.9, x3 = 4.96, k1 = -0.028, k2 = 0.23, b = 0.068
  ))

# \donttest{
example_df <- water_df %>%
  define_water_df() %>%
  dplyr::mutate(FerricDose = seq(1, 12, 1)) %>%
  chemdose_toc_df(ferricchloride = FerricDose, coeff = "Ferric")

example_df <- water_df %>%
  define_water_df() %>%
  dplyr::mutate(ferricchloride = seq(1, 12, 1)) %>%
  chemdose_toc_df(coeff = "Ferric", pluck_cols = TRUE)
# }