Desalination Technology is developing globally very fast these days. More and more desalination technologies getting applied into the conventional water treatment business today. DME does follow and support this development on an international basis starting from the first idea up to commodity products.
Desalination technology is used by humans since thousands of years. Being in the desert surrounded by sand and rocks or being on the sea sailing through salty waters, always fresh water is needed every day to keep the human body in a balanced hydrate mode.
Nature started using desalination processes from the very first moment. Different concentration levels drive everything alive on our planet. Humans started using first evaporation and condensation processes to purify unusable water. In the last century the number of processes to desalinate water and other liquids has gone through a very big development. New processes have been […]
Saving material and energy per ton of water produced is the main target of all developments in desalination. Due to this basic attempt every of the today known technology has to prove its benefits against the established ones. Not pointing out every new technology three of them are selected and briefly described at this stage (2017).
Obviously an idea for a technology needs to develop. On the right hand side you can see an overview of different technologies. This sketch does illustrate the state of science knowledge and in the same way the state of Development, Technology and Art.
Legend: State of […]
Multiple-Effect Distillation (also Multi Effect Distillation or MED) is a thermal distillation technology based on evaporation and condensation processes in multiple stages, called effects, that is mainly used for desalination. In most MED plants, the seawater enters all the effects in parallel and is raised to the boiling point after being preheated on tubes. The seawater is either sprayed or otherwise distributed onto the surface of the evaporator tubes in a thin film to further rapid boiling and evaporation. The tubes are heated by steam from a boiler or some other source, which is condensed on the opposite side […]
Multi-Stage Flash (MSF) evaporation desalination plants are based on flash evaporation in a cascade of stages (effects) at different pressure levels. In the brine-recirculation mode, the brine is recirculated through the system.
In the last stage of an MSF plant, the heated feed water is led into the pressure vessel where it partially evaporates in a flashing process due to the pressure decline. The vapour is used to preheat the feed water. The part of the brine that does not evaporate is sucked into the next stage which has a lower pressure. There, the same flashing and evaporation procedure takes place […]
Membrane Distillation (MD) is a thermal desalination process in which water vapour is transported through a hydrophobic porous membrane. Due to a partial pressure difference of vapour between a liquid surface and an air or gas stream, water is vaporised although the liquid phase is much below boiling temperature. A hydrophobic membrane can separate the two phases – liquid water and either vapour or vapour-gas mixture – in order to avoid the transfer of liquid or allow compact stream arrangements. Thus, MD is a non-isothermal membrane separation process with combined heat and mass transfer over the membrane. Parallel arrangement […]
The Multiple-Effect Humidification (MEH) process for the extraction of water from salt-, brackish and well water represents a thermal method that is based on the well-known principle of evaporation (humidifier) and subsequent condensation (dehumidifier). The performance of this natural process was improved in the MEH process such that a major portion of the used evaporation energy remains within the process, permitting the low-temperature extraction of drinking water effectively and reasonably, without much waste heat, even in smaller units. The technical design of the process describes the natural water cycle, from evaporation (sea surface to atmosphere) to condensation (warm air […]