controls. Spent process fluid discharged to wastewater. Product applied in aqueous process solution with negligible volatilization. Substance Use The substance maximum 10 mg/L is a At an assumed Rate use rate in a typical typical water flow rate of 10000 operation (MSPERC) is treatment m3/d, and usage 100 kg/d chemical (e.g., concentration of10 polyacrylamide) mg/L, the usage substance use rate concentration is 100 kg/d (OECD, 2004)1 Days Emitting 300 days/year Industry None knowledge* Environmental Assumed dilution factor in ERC default None Parameters for freshwater is 10. For settings2 marine assessments an Fate Calculation additional tenfold dilution is assumed, i.e., dilution factor in marine water = 100. *Assumed that water treatment chemicals are typically used consistently throughout the year. 1OECD Series on Emission Scenario Documents, Number 4. June 2004. Emission Scenario Document on Water Treatment Chemicals. 2 Characteristics of Specific ERC Justification Emission To Air 0.05 Substances purposely released Fractions to water. Likely some loss to (from the air for volatiles, thus, an process) assumed loss of 5%. Value confirmed via an air flotation unit simulated using the ToxChem+ model To 0.95 Substance purposely released Wastewater/Sewer/ to water, thus, emission factor Water courses will be near 100%.1 Value derived on basis of mass conservation, assuming 5%
controls. Spent process fluid discharged to wastewater. Product applied in aqueous process solution with negligible volatilization. Substance Use Rate The substance maximum use rate in a typical operation (MSPERC) is 100 kg/d 10 mg/L is a typical water treatment chemical (e.g., polyacrylamide) usage concentration (OECD, 2004)1 At an assumed flow rate of 10000 m3/d, and usage concentration of10 mg/L, the substance use rate is 100 kg/d Days Emitting 300 days/year Industry knowledge* None Environmental Parameters for Fate Calculation Assumed dilution factor in freshwater is 10. For marine assessments an additional tenfold dilution is assumed, i.e., dilution factor in marine water = 100. ERC default settings2 None *Assumed that water treatment chemicals are typically used consistently throughout the year. 1OECD Series on Emission Scenario Documents, Number 4. June 2004. Emission Scenario Document on Water Treatment Chemicals. 2 Characteristics of Specific ERC Justification Emission Fractions (from the process) To Air 0.05 Substances purposely released to water. Likely some loss to air for volatiles, thus, an assumed loss of 5%. Value confirmed via an air flotation unit simulated using the ToxChem+ model To Wastewater/Sewer/ Water courses 0.95 Substance purposely released to water, thus, emission factor will be near 100%.1 Value derived on basis of mass conservation, assuming 5%
21-_ESVOC_3.22a.v1_SPERCS_revised-Factsheet_Feb2013_Water_Treatment_Che....docx