Phosphoric acid production

To use this category, specify the region from which the phosphate rock feedstock originates using the region drill choice. A default value for the inorganic carbon content of the phosphate based on US EPA guidelines is used. Users can override these values if appropriate (see below).

Next, specify the quantity of phosphate consumed using the mass profile item value. The returned amount represents CO₂e emissions associated with this quantity based on a default value.

To override the default carbon content set the value as a whole percentage (i.e. 0-100) using the massInorganicCarbonPerMass profile item value. If using the 'other' option from the region' drill choice, then such a value for inorganic carbon must be specified since there are no associated default values.

Time-dependent calculations

The mass profile item value can be expressed in terms of a specific period of time, by using the -Unit and -PerUnit profile item designations. In conjunction, users can set the duration for which the facility was in operation, by setting the operatingDuration profile item value. In this case, the time basis of each quantity is automatically taken into account. If users specify an operating time for the facility in terms of hours (h), and the quantity of phosphate feedstock in terms of days (day), for example, Discover will handle the necessary conversions and return a value for emissions during the specified operating time.

User should note that, in the case where all values use the same basis for time, the emissions calculation simply reflects the absolute values for consumption/recovery specified and is effectively independent of particular timeframe. This is the default condition of the calculation: all values are specified on an annual basis with the operating time assumed to be 1 year. As such, if the operatingDuration is left unspecified the returned emission simply reflects the absolute inputs.