tidywater (version 0.9.0)

ozonate_bromate: Calculate bromate formation

Description

Calculates bromate (BrO3-, ug/L) formation based on selected model. Required arguments include an object of class "water" created by define_water ozone dose, reaction time, and desired model. The function also requires additional water quality parameters defined in define_water including bromide, DOC or UV254 (depending on the model), pH, alkalinity (depending on the model), and optionally, ammonia (added when defining water using the tot_nh3 argument.) For a single water use ozonate_bromate; for a dataframe use ozonate_bromate_chain. Use pluck_water to get values from the output water as new dataframe columns. For most arguments in the _chain 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

ozonate_bromate(water, dose, time, model = "Ozekin")
ozonate_bromate_chain(
  df,
  input_water = "defined_water",
  output_water = "ozonated_water",
  dose = "use_col",
  time = "use_col",
  model = "use_col"
)

Value

ozonate_bromate returns a single water class object with calculated bromate (ug/L).

ozonate_bromate_chain returns a data frame containing a water class column with updated bro3.

Arguments

water

Source water object of class "water" created by define_water

dose

Applied ozone dose (mg/L as O3). Results typically valid for 1-10 mg/L, but varies depending on model.

time

Reaction time (minutes). Results typically valid for 1-120 minutes, but varies depending on model.

model

Model to apply. One of c("Ozekin", "Sohn", "Song", "Galey", "Siddiqui")

df

a data frame containing a water class column, which has already been computed using define_water_once. The df may include a column named for the applied chlorine dose (cl2), and a column for time in minutes.

input_water

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

output_water

name of the output column storing updated parameters with the class, water. Default is "ozonated_water".

Details

For large datasets, using fn_once or fn_chain may take many minutes to run. These types of functions use the furrr package for the option to use parallel processing and speed things up. To initialize parallel processing, use plan(multisession) or plan(multicore) (depending on your operating system) prior to your piped code with the fn_once or fn_chain functions. Note, parallel processing is best used when your code block takes more than a minute to run, shorter run times will not benefit from parallel processing.

Examples

example_dbp <- define_water(8, 20, 66, toc = 4, uv254 = .2, br = 50) %>%
  ozonate_bromate(dose = 1.5, time = 5, model = "Ozekin")
example_dbp <- define_water(7.5, 20, 66, toc = 4, uv254 = .2, br = 50) %>%
  ozonate_bromate(dose = 3, time = 15, model = "Sohn")


library(dplyr)

example_df <- water_df %>%
  slice_head(n = 6) %>%
  mutate(br = 50) %>%
  define_water_chain() %>%
  mutate(
    dose = c(seq(.5, 3, .5)),
    OzoneTime = 30
  ) %>%
  ozonate_bromate_chain(time = OzoneTime, model = "Sohn")

# \donttest{
# Initialize parallel processing
library(furrr)
# plan(multisession)
example_df <- water_df %>%
  mutate(br = 50) %>%
  define_water_chain() %>%
  ozonate_bromate_chain(dose = 4, time = 8)

# Optional: explicitly close multisession processing
# plan(sequential)
# }