Methods for Adding Additives and Calculating Additive Quantity

The system provides five methods for adding additives and calculating the additive quantity:

• Fixed quantity.

  You add a fixed quantity of the additive to the vessel and lot.

• Targeted Parts Per Million (PPM).

  The system calculates how much additive quantity to add to the vessel or lot based on a targeted concentration of the active ingredient. The concentration is expressed as parts per million (PPM) of an active ingredient: PPM = 1 milligram ÷ 1 liter.

  You must select the ingredient to be targeted within the grid, specify the targeted PPM, and click the Calculate button. The system calculates the quantity of the additive that is necessary to meet the targeted PPM.

• Rate

  The system calculates the total quantity of an additive based on a specified rate. For example, you might want to add 10 grams of an additive every 10 minutes for the duration of the operation (two hours). The system calculates the total additive quantity for the operation to equal 120 grams. Specify the rate quantity and rate interval when using this method.

• Flow

  The system calculates the total quantity of an additive based on a flow. For example, you might want to add 10 grams of an additive for every 100 gallons in the vessel. If the vessel contains 2000 gallons, the system calculates the amount of additive that you must add during that operation (in this case, 200 grams). Specify the flow quantity and per volume quantity when using this method.

• Total Vessel Volume

  Note: The Total Vessel Volume method is enabled only in the Additive Workbench.

  When you select the Total Vessel Volume option, you can add additive quantities based on the total volume of the group of vessels that you select. For example, if you select three vessels to which you want to add a total of 10 pounds of an additive, the system adds a portion of the 10 pounds to each vessel in proportion to the total volume of each vessel. Note that the system calculates the proportion in relation to the volume, which is the amount in the vessel, and not in relation to the capacity, which is the maximum volume that the vessel can hold.

  The purpose of the total vessel volume calculation method is to add a proportionate amount of the additive to multiple vessels. The system enables you to use the total vessel volume calculation when you select only one vessel to which to add an additive. However, because the proportion of the additive for only one vessel is 100%, the effect of using the total vessel volume method for one vessel is the same as the effect of selecting the fixed calculation method.