The use of ice slurries dates back many millenniums, e.g. the ancient Romans applied the cooling of snow-water and ice-water mixtures. Approximately two decades ago a breakthrough of the new technology of producing ice slurries has set in the refrigeration domain for the cooling of shops and supermarkets. After some difficulties at the beginning, it is now possible to build systems, which operate as designed. However, there is still a huge potential to lower the energy consumption and the costs of the systems. Actions in this direction are the design of new ice slurry generators, the development of new concepts for storage and mixing, etc. In this article a short review of the basic research on ice slurries is presented. Furthermore, practical problems of the application of the technology in refrigeration and process techniques are discussed.

From physical properties of ice slurries to industrial ice slurry applications

The present study reports on the performance characteristics of the centrifugal slurry pump with multi-sized particulate slurry of bottom ash and fly ash mixtures. The performance characteristic of the pump was experimentally evaluated at rotational speed 1450 rpm for bottom ash slurries with and without the addition of fly ash in the concentration range of 10% to 50% (by weight). Addition of fly ash in the bottom ash was varied from 10% to 30% (by weight). The pump total head, overall efficiency, and pump input power at different flow rates were evaluated. The performance characteristics results show that the value of head and the efficiency of the pump depend on the solid concentration. It was also observed that the performance parameter of the pump strongly depends on slurry properties. The addition of fine particles fly ash in the coarser particles of bottom ash slurry, leads to reduce the additional head losses in the pump. The pump performance in terms of head and efficiency improved with addition o...

Performance Characteristics of Centrifugal Slurry Pump with Multi-Sized Particulate Bottom and Fly Ash Mixtures

https://spectrum.library.concordia.ca/15141/1/Tamasauskas_MASc_F2011.pdf

Modeling and optimization of a solar assisted heat pump using ice slurry as a latent storage material

Flow and heat transfer characteristics of ice slurry in typical components of cooling systems: A review

This paper presents an experimental and numerical investigation of the flow of ice slurry, composed of monopropylene glycol (MPG) as an additive. The objective is to demonstrate the influence of initial concentrations of this additive and the ice fraction on the rheological behavior of the corresponding ice slurry. The ice slurry flow was modeled in a continuous approach, where the fluid is assumed to behave like a single-phase fluid. Complex fluid behavior is treated by an effective kinematic viscosity, which depends on several parameters. In the present study the rheological model of Ostwald-de Waele is applied. The results – which concern mainly the effect of velocity, ice mass fraction and solute concentration on the pressure drop – show an overall close agreement between the experimental and the numerical and analytical results.

Physical modeling, numerical simulations and experimental investigations of Non-Newtonian ice slurry flows

The characteristics of three different principles of pumps—centrifugal, side-channel and screw—were investigated. For each type, the pump characteristics at three speeds of rotation and for four different ice fractions between 0 and 25% were determined. The pump total head, overall efficiency, and electrical power input in function of the volume flow rate were continuously measured. In the case of a centrifugal- or a side channel-pump, the measured pump characteristics with ice fractions between 0 and 15% were nearly of equal value. Marked differences were observed with ice fractions of 25%. In the case of a screw pump, characteristics and behaviour were different compared to the centrifugal and side channel-pump. For increasing ice fractions, the obtained values show a gradually altering behaviour. If the pressure and the speed of rotation are constant, the volume rate of flow increases with growing ice mass fraction. The overall efficiency is significantly lower without ice particles than with ice mass fractions of 5–25%. All tested pumps were running over hundreds or thousands of hours and were suitable for ice slurry applications.

B. Frei

Papers

Characteristics of different pump types operating with ice slurry