Introduction to Desalination. Louis Theodore

health or the environment is often very low. Many emerging contaminants, for example PFAS (per- and polyfluoroalkyl substances) are very persistent in the environment and in the human body, and there is evidence that exposure to PFAS can lead to adverse human health effects. The drinking water health advisory for two of these PFAS compounds, PFOA and PFOS, is 70 parts/trillion or 70 ng/L. For these two PFAS compounds, determine the following: (1) what is their daily dose at the health advisory limit if the average adult water consumption rate is 1 L/d? (2) if a desalination plant is treating combined brackish water and recharged treated wastewater at a ratio of 50 to 1 on a volume basis, the concentration of PFOA + PFOS in the treated wastewater is 8 ng/L, and the plant is expected to provide 98% PFAS removal, what is the margin of exposure (MOE = NOEL/Actual Dose, g/d) if the health advisory limit dose from (1) is assumed to be the no-observed-adverse-effect level (NOEL)? (3) If the MOE is recommended to be > 100, comment on the MOE for this facility and indicate any corrective action or modified operating conditions that should be implemented to ensure the safety of this produced water supply.

      References

      1 Abulencia, P. and Theodore, L. (2007). Fluid Flow for the Practicing Chemical Engineer. Hoboken, NJ: John Wiley & Sons.

      2 Dupont, R.R., Ganesan, K., and Theodore, L. (2016). Pollution Prevention, Industrial Ecology, Green Science and Engineering, and Sustainability. Boca Raton, FL: CRC Press/Taylor and Francis Group.

      3 Felder, R. and Rousseau, R. (1986). Elementary Principles of Chemical Processes, 2nd Edition. Hoboken, NJ: John Wiley & Sons.

      4 Green, D.W. and Perry, R.H. (2008). Perry's Chemical Engineer's Handbook, 8th Edition. New York, NY: McGraw-Hill.

      5 Kauffman, D. (1992). Process Synthesis and Design, a Theodore Tutorial. East Williston, NY: Theodore Tutorials. Originally published Research Triangle Park, NC: USEPA/APTI.

      6 McCabe, W., Smith, J., and Harriot, P. (1993). Unit Operations of Chemical Engineering, 5th Edition. New York, NY: McGraw-Hill.

      7 Prochaska, C. and Theodore, L. (2018). Introduction to Mathematical Methods for Environmental Engineers and Scientists. Salem, MA: Scrivener/Wiley.

      8 Reynolds, J. (1992). Material and Energy Balances, a Theodore Tutorial. East Williston, NY: Theodore Tutorials. Originally published Research Triangle Park, NC: USEPA/APTI.

      9 Theodore, L. (2011). Heat Transfer for the Practicing Chemical Engineer. Hoboken, NJ: John Wiley & Sons.

      10 Theodore, L. (2014). Chemical Engineering: The Essential Reference. New York, NY: McGraw-Hill.

      11 Theodore, L. and Behan, K. (2018). Introduction to Optimization for Chemical and Environmental Engineers. Boca Raton, FL: CRC Press/Taylor and Francis Group.

      12 Theodore, L. and Ricci, F. (2010). Mass Transfer Operations for the Practicing Engineer. Hoboken, NJ: John Wiley & Sons.