# Accession Number:

## ADA043716

# Title:

## Process Design for Treating Shower Wastewater by Ultrafiltration.

# Descriptive Note:

## Final rept.,

# Corporate Author:

## ARMY MOBILITY EQUIPMENT RESEARCH AND DEVELOPMENT COMMAND FORT BELVOIR VA

# Personal Author(s):

# Report Date:

## 1977-06-01

# Pagination or Media Count:

## 177.0

# Abstract:

This report investigates curve fitting for the empirical explanation of shower wastewater treatment by ultrafiltration. A two-part model is proposed where, initially, the system is at unsteady state caused by the formation of the boundary layer. Later, the system comes to a steady state when the rates of boundary layer formation and decay reach constant values. The unsteady state portion is described by an exponential equation and the steady state portion is described by a linear equation. The model was evaluated on two separate ultrafiltration systems with each system utilizing a different membrane configuration. These configurations were the spiral-wound configuration which fit the model as stated and the hollow-fiber configuration which fit only the unsteady state portion of the model due to daily removal of the boundary layer. The study concludes that a. A single, empirical equation cannot describe permeate production by ultrafiltration of shower wastewater. b. A model based on unsteady and steady state phenomena of concentration polarization can empirically describe the ultrafiltration process. c. The hollow-fiber system can be described by a single, empirical equation of exponential order because the system as studied was never allowed to reach steady state. Therefore, the unsteady state equation described the systems operation. d. The spiral-wound membrane system can be described empirically by an exponential equation during the boundary layer formation and by a linear equation during steady state operation. Author

# Descriptors:

# Subject Categories:

- Numerical Mathematics
- Pumps, Filters, Pipes, Tubing, Fittings and Valves
- Water Pollution and Control