Rheological Analysis of Mud: Towards an Implementation of the Nautical Bottom Concept in the Port of Hamburg

The nautical bottom (the level at which contact with a ship’s keel causes either damage or unacceptable effects on controllability and manoeuvrability of a ship) should be associated to a measurable physical characteristic. Bulk density is typically used as a criterion for nautical bottom by many ports worldwide. However, the rheological...

Why do settling and yield stress of mud differ in european ports?

In some ports and waterways, hindered (delayed) settling of mud suspended in the water phase can be detected. Hindered settling phenomena are typically linked to a combination of sediment properties, suspended sediment concentration or density, hydrodynamic conditions, presence or absence of organic bridging between mud particles and the...

Tuning the rheological properties of kaolin suspensions using biopolymers

Kaolin based suspensions have wide range of applications such as slurry wall, drilling fluids, adhesives, cosmetics, refractories and pharmaceuticals, due to their abundance in nature, low cost and non-swelling nature. On the other hand, the unique properties (i.e., biodegradability) of biopolymers make them suitable candidate for variety of...

From fundamentals to implementation of yield stress for nautical bottom: Case study of the Port of Hamburg

The nautical bottom (i.e., the level at which contact with a ship’s keel causes either damage or unacceptable effects on controllability and manoeuvrability of a ship) should be associated to a measurable physical characteristic. Bulk density is typically used as a criterion for nautical bottom by many ports worldwide. However, the rheological...

Effect of organic matter degradation in cohesive sediment: A detailed rheological analysis

Purpose<br/>The presence of organic matter in cohesive sediment results in the formation of clay-organic flocs, which eventually impart complex rheological behavior including shear-thinning, viscoelasticity, thixotropy and two-step yielding to mud. In this study, the influence of microbial degradation of sediment organic matter on the...

Rheology and yielding transitions in mixed kaolinite/bentonite suspensions

Kaolinite suspensions are known to have quite fast settling behaviour and Newtonian character, particularly at low concentrations, due to the non-swelling nature of their constitutive particles. On the other hand, bentonite is known for its swelling and interacting nature, which leads to the formation of a network structure, even at low...

Rheology of Mud: An Overview for Ports and Waterways Applications

Mud, a cohesive material, consists of water, clay minerals, sand, silt and small quantities of organic matter (i.e., biopolymers). Amongst the different mud layers formed by human or natural activities, the fluid mud layer found on top of all the others is quite important from navigational point of view in ports and waterways. Rheological...

Bigels and multi-component organogels: An overview from rheological perspective

Background: Polymeric gels, an important class of soft matter systems, are widely used for commercial applications particularly in food products (i.e., saturated fat replacement). The efficiency of the product for a particular application can be directly linked to its rheological signature. However, the rheological imprint of these structured...

Flocculation of clay suspensions by anionic and cationic polyelectrolytes: A systematic analysis

The characteristics of clayey suspensions, majorly composed of quartz microparticles, in the presence of anionic and cationic polyelectrolytes were investigated using different techniques. A wide range of clay concentrations was used, i.e., from 0.07 to 1000 g/L for different experimental techniques, based on the fact that the clay...

Interfacial and bulk stabilization of oil/water system: A novel synergistic approach

Oil/water emulsions are usually stabilized either by interfacial modification using nanoparticles and surfactants (stated as pickering emulsion or bijels) or by bulk stabilization with the help of low‐molecular‐weight or polymeric gelators (known as bigels) in response to some external stimuli (e.g., pH, temperature). Both these approaches...

Yield stress measurements of mud sediments using different rheological methods and geometries: An evidence of two-step yielding

Yield stress materials have a wide range of commercial applications. Yet, the suitable way of determining the yield stress values of a given material has been the subject of many studies and debates. Yield stresses are dependent on the material (shear) history and composition, which implies that robust protocols should be developed to study...

Rheological analysis of mud from Port of Hamburg, Germany

Purpose: An innovative way to define navigable fluid mud layers is to make use of their rheological properties, in particular their yield stress. In order to help the development of in situ measurement techniques, it is essential that the key rheological parameters are estimated beforehand. Is there only one yield stress? In which shear rate...

Is density enough to predict the rheology of natural sediments?

Mud is a cohesive material which contains predominantly clay minerals, water, organic matter and some amounts of silt and sand. Mud samples can have complex rheological behaviour, displaying viscoelasticity, shear-thinning, thixotropy and yield stress. In this study, influence of organic matter on the rheological behaviour of different mud...

Rheology of Pure Ionic Liquids and Their Complex Fluids: A Review

Ionic liquids (ILs) are liquid salts at ambient or lower temperatures and consist of ions and short-lived ion pairs. They are potential alternatives to toxic, hazardous, highly flammable, and volatile solvents for preparing solutions, dispersions, gels, composites, and polymeric melts. ILs have some very interesting and unique characteristics...