Publications by authors named "S G J Heijman"

Sodium hypochlorite (NaClO) is widely used for the chemical cleaning of fouled ultrafiltration (UF) membranes. Various studies performed on polymeric membranes demonstrate that long-term (>100 h) exposure to NaClO deteriorates the physicochemical properties of the membranes, leading to reduced performance and service life. However, the effect of NaClO cleaning on ceramic membranes, particularly the number of cleaning cycles they can undergo to alleviate irreversible fouling, remains poorly understood.

View Article and Find Full Text PDF

There is a global need for optimizing the use of water that has resulted from increased demand due to industrial development, population growth, climate change and the pollution of natural water resources. One of the solutions is to use reclaimed water in industrial applications that do not require water of potable quality, such as cooling water. However, for cooling water, (treated) wastewater's hardness is too high, apart from having a high load of suspended solids and organic matter.

View Article and Find Full Text PDF

This work investigates the enhancement of antifouling properties of ceramic nanofiltration membranes by surface modification atomic layer deposition (ALD) of TiO. Feed solutions containing bovine serum albumin (BSA), humic acid (HA) and sodium alginate (SA) were used as model foulants. The classic fouling mechanism models and the modified fouling indices (MFI) were deduced from the flux decline profiles.

View Article and Find Full Text PDF

Ceramic membranes have drawn increasing attention in oily wastewater treatment as an alternative to their traditional polymeric counterparts, yet persistent membrane fouling is still one of the largest challenges. Particularly, little is known about ceramic membrane fouling by oil-in-water (O/W) emulsions in constant flux filtration modes. In this study, the effects of emulsion chemistry (surfactant concentration, pH, salinity and Ca) and operation parameters (permeate flux and filtration time) were comparatively evaluated for alumina and silicon carbide (SiC) deposited ceramic membranes, with different physicochemical surface properties.

View Article and Find Full Text PDF
Article Synopsis
  • This study is the first detailed analysis of how ceramic membranes can effectively remove natural organic matter (NOM) from drinking water in South Africa, focusing on various organic fractions like biodegradable dissolved organic carbon (BDOC) and fluorescent dissolved organic carbon (FDOM).
  • Ceramics showed impressive results, removing over 80% of dissolved organic carbon (DOC) from coastal water sources and between 60%-75% from inland sources, with more than 85% removal of BDOC and high removal rates of hydrophobic fractions.
  • The research highlights that UV removal rates closely correlate with the removal efficiency of NOM, indicating that using UV levels can help predict how well ceramic membranes can filter out organic contaminants in existing water treatment plants.
View Article and Find Full Text PDF