Effects of a sidestream concentrated oxygen supply system on the membrane filtration performance of a high-loaded membrane bioreactor

To investigate the influence of high-pressure and shear effects introduced by a concentrated oxygen supply system on the membrane filtration performance, a laboratory-scale membrane bioreactor (MBR) fed artificial municipal wastewater was operated continuously for 80 days in four phases equipped with different aerations systems: (P1) bubble...

Adsorption and cake layer fouling in relation to Fenton cleaning of ceramic nanofiltration membranes

Catalytic ceramic nanofiltration (NF) is a promising technology for direct wastewater reclamation, given its high separation selectivity and reactive surfaces for oxidative removal of fouling. A better understanding of the relation between fouling types and oxidative cleaning efficacy under high organic loading conditions is of practical...

Improving MFI-UF constant flux to more accurately predict particulate fouling in RO systems: Quantifying the effect of membrane surface porosity

This study aimed to quantify the effect of membrane surface porosity on particulate fouling predicted by the MFI-UF method at constant flux. Firstly, the surface porosity of polyethersulfone UF membranes (5–100 kDa) was determined using ultra-high resolution SEM. Thereafter, the MFI-UF was measured using suspensions of polystyrene particles ...

A spatially resolved model for pressure filtration of edible fat slurries

A spatially resolved one dimensional pressure filtration model was developed for a slurry of edible fat crystals. The model focuses on the expression step in which a cake is compressed to force the liquid through a filter cloth. The model describes the local oil flow in the shrinking cake modeled as a porous nonlinear elastic medium existing...

Static and dynamic stickiness tests to measure particle stickiness

Sticking of particles has a tremendous impact on powder-processing industries, especially for hygroscopic amorphous powders. A wide variety of experimental methods has been developed to measure at what combinations of temperature and moisture content material becomes sticky. This review describes, for each method, how so-called stickiness...

Cakevr: A social virtual reality (vr) tool for co-designing cakes

Cake customization services allow clients to collaboratively personalize cakes with pastry chefs. However, remote (e.g., email) and in-person co-design sessions are prone to miscommunication, due to natural restrictions in visualizing cake size, decoration, and celebration context. This paper presents the design, implementation, and expert...

Real-time in-situ rheological assessment of sticky point temperature and humidity of powdered products

Unwanted changes in powder flow behavior can unexpectedly occur when a product is exposed to certain conditions of temperature and humidity. This can happen during production, but also during transport or storage. The work reported here demonstrates the novel approach of using an amended powder rheology set-up for measuring and predicting...

Skin friction of diaphragm walls: An experimental study based on modified direct-shear tests

This thesis aims to analyse the conservatism in the current Dutch recommendations on the external friction angle 𝛿 of diaphragm walls: 𝛿 = 𝑚𝑖𝑛[𝜙, 20°] (for curved slip surfaces) (CUR/COB, 2010), by means of an experimental investigation. Based on literature, two sources of conservatism are identified: 1) filter cake contamination by excavated...

Application of dynamic membranes in anaerobic membranes in anaerobic membrane bioreactor systems

Anaerobic membrane bioreactors (AnMBRs) physically ensure biomass retention by the application of a membrane filtration process. With growing application experiences from aerobic membrane bioreactors (MBRs), the combination of membrane and anaerobic processes has received much attention and become more attractive and feasible, due to advantages...

The evaluation of two different PAC operations in combination with submerged ceramic MF membranes in surface water treatment

Powdered Activated Carbon (PAC) has been successfully used in conjunction with membrane microfiltration (MF) to reduce taste, odour, colour and other concerns caused by organic material present in raw drinking water sources. PAC addition also significantly reduces the extent of fouling in membranes. And the operation of continuously dosed PAC...

Crossflow ultrafiltration of raw municipal wastewater: Investigations using PVDF tubular membranes

In the usual wastewater treatment schemes the application of membranes follows a biological process. However, ultrafiltration of untreated wastewater produces permeate free of particles and bacteria in one single step and could represent the starting point for new water-reuse concepts. This thesis focuses on crossflow ultrafiltration of raw...