An agent-based modelling and simulation framework to support strategic cargo airlift evaluation

When there is a need to move cargo across the world in the fastest possible manner, airlift is the prime solution. Due to the potential extreme requirements of airlift, aircraft have to be capable of performing in a myriad of operational environments. To support future aircraft design loops, this work proposes a framework which couples aircraft...

Effects of micro-bubble aeration on the pollutant removal and energy-efficient process in a floc-granule sludge coexistence system

To investigate energy-saving approaches in wastewater treatment plants and decrease aeration energy consumption, this study successfully established a floc-granule coexistence system in a sequencing batch airlift reactor (SBAR) employing micro-bubble aeration. The analysis focused on granule formation and pollutant removal under various...

Alleviating mass transfer limitations in industrial external-loop syngas-to-ethanol fermentation

Mass transfer limitations in syngas fermentation processes are mostly attributed to poor solubility of CO and H₂ in water. Despite these assumed limitations, a syngas fermentation process has recently been commercialized. Using large-sale external-loop gas-lift reactors (EL-GLR), CO-rich off-gases are converted into ethanol, with...

Kinetics of different bioreactor systems with Acidithiobacillus ferrooxidans for ferrous iron oxidation

The relative performance of two biofilm-based airlift reactors using different kinds of packing materials and one fixed bed biofilm reactor with a homemade packing material of high specific area (~ 1000 m²/m³) was addressed. The bioreactors operated under ferrous iron loading rates in the range of 8–120 mol Fe(II)/m<sup...

Modelling of the drilling rates for large diameter offshore foundation piles

In a world where the awareness of global warming and climate change increases, the shift towards sustainable energy is essential. In the upcoming years, an increasing number of offshore wind farms is expected. Over the past years, all the 'best spots' are taken and the new locations in tougher soil conditions or even rock have to be overcome....

A finite element model for high enthalpy two-phase flow in geothermal wellbores

This paper introduces a computational model for transient high enthalpy fluid flow through geothermal wellbores. The drift-flux model is utilized to formulate the physical behavior of fluid, and the constitutive relationships are described using relevant equations of state and empirical relationships. The governing equations are solved using...

Thermally destratifying lakes against blue algae with rising air bubbles

Mixing systems are used in deep lakes to prevent blue algae from rapidly growing. Air bubbles rise from the bed, dragging water from below upwards. The resulting vertical circulation suppresses blue algae growth. However, these systems demand electricity of about €25,000 per km2 per year. The airlift promises to mix the water more efficiently,...

Continuous Membrane-assisted Airlift Crystallization

In previous research, batch experiments with an airlift crystallizer on ammonium sulphate, adipic acid and L-ascorbic acid have shown significant reduction of secondary nucleation compared to conventional stirred crystallizers. Furthermore, the crystal size distribution (CSD) achieved by the airlift crystallizer is almost 60% narrower than the...

Technologies for Optimisation and Control of Nucleation and Growth for New Generations of Industrial Crystallizers

The scope of this thesis is to study new methods for control of the most important phenomena in crystallization processes: nucleation and crystal growth. In order to achieve this, novel process equipment, which utilize alternative driving forces, were developed. It was proven that primary nucleation for solution crystallization can be controlled...

Vertical Transport Methods in Deep Sea Mining

A comparison between 4 different transport methods which could be used for transporting offshore mined resources between sea floor and surface: multiple centrifugal pumps, positive displacement (diaphragm) pump, mechanical lifting and airlift.

Development of a task-based design approach for solution crystallization processes

Crystallization is historically one of the most important separation and product formation technologies in chemical industry. The future impact of crystallization is expected to increase as new high-added value products are often in crystalline form and need to comply with increasingly stringent product quality requirements. This calls for...

Crystal Growth in a novel airlift crystallizer

Crystal growth in a high electrolyte and ionic shear enviroment, minimizing attrition and maximizing control over crystal growth and size.