Presentations by David A. Ladner, PhD, PE
Matches: 7
Removal of Inorganic Scale from RO Membranes using Dissolved CO2
Membrane fouling is a major operational issue in reverse osmosis (RO) desalination plants. In particular, plants treating brackish groundwater can encounter troublesome inorganic membrane scales. A novel cleaning method is proposed to remove inorganic scales from fouled RO membranes using dissolved CO2. A comparison of cleaning methods is discusse...
Aggregation of Superfine Carbon for Improved Filtration Performance
Examines the use of superfine powdered activated carbon particles as pretreatment....
Comparison of Computational Fluid Dynamics (CFD) and Experimental Data for Fouling Mitigation with Sinusoidal Reverse Osmosis Spacer
This paper describes work done on a series of novel sinusoidal spacers that can form unobstructed sinusoidal membrane channels and the performance of various novel sinusoidal spacers and the conventional mesh spacer on mitigating foulant deposition onto membrane surface. Data was evaluated both experimentally on a bench-scale RO system and numerica...
Membrane Filtration of Colloidal Activated Carbon: Considerations for Optimization of Head Loss Reduction and Small Molecule
This paper describes the use of microfiltration membrane for the filtration of colloidal activated carbon. Efforts were made to minimize head loss and small molecule adsorption. The effects of source water quality and particle size were evaluated. The presence of natural organic matter (NOM) proved to be a confounding factor. Two methods were test...
Effects of Dissolved CO2 on Organic and Inorganic Fouling and Cleaning of RO Membranes
Reverse osmosis (RO) is a membrane treatment process used to separate dissolved solutes from water. This technique has become increasingly popular due to the variety of objectives it may accomplish, including desalination of seawater or brackish water, advanced treatment for water reuse, softening, natural organic matter removal to minimize disinfe...
Concentration Polarization Modeling for Reverse Osmosis Membranes with Engineered Surface Features
Fouling has always been an issue in all membrane systems, and it is more problematic when concentration polarization (CP) is high.This research investigates how patterns can affect CP layer in a reverse osmosis (RO) or nanofiltration (NF) system by evaluating the effects of velocity, pressure drop, concentration distribution and shear stress on the...
Toward Optimized Membrane Unit Processes Via Multi-Scale Modeling
This work is at the interface of research and practice, which is ideal for the Membrane Technology Conference. We take our academic understanding of membranes and computer modeling techniques and show how it can enhance the process engineering work being done by those in the field....