Importance of a Liquid-Liquid Coalescing System

By Columninternals    7 / Feb / 2019    In Category Industrial


One of the issues that distillation column systems often face is to be able to efficiently separate two or more immiscible fluids. As a matter of fact, this hampers the process flow and therefore needs to be corrected at any cost. One way in which this is done is by the use of liquid coalesce. What is liquid-liquid? Generally, this system is created by using a mix of structured packaging with parallel plates and a knitted mesh. The correct combination and orientation of these elements would depend on the specific application that it would be used for.

This process can usually be done in any one of the two ways. The first and the foremost is to mix all the immiscible liquids in mechanical mixers and apply increased pressure to increase the surface free energy of each fluid, thus giving rise to the droplets. The second and the other way is to cool the saturated liquid below the solution point. This kind of procedure helps the solute phase to condense out from the solution. Once done, it helps in the formation of a second liquid phase.

The reason this is needed is that some column internals does not include adequate arrangements for the separation of liquids inside the separator drums. Many process leaders go for retrofit these vessels for achieving the desired result. But the use of a coalescing system is by far the most efficient. The elements in a liquid-liquid coalescing set up consist of the vessel, the coalescing media, liquid distributors, vortex breakers and mist eliminators. Let us look at some of the applications of such a system. 

Often, we find haze in distillates inside the column, an efficient liquid-liquid coalescing system can remove haze from the distillates. Once the product washing is done, this particular system helps to remove fluids like water, and even salts and other caustic materials. In the refineries around the world, this system is widely used. Its use is common in the effluent treatment and also in the main settler tank. Often coalescing matter is also used in the treatment of wastewater, and also in glycol and amine towers.

A liquid-liquid coalescer has several distinct advantages to take note of. When you use an efficient coalescing system, you can make do with smaller sized liquid-liquid separator vessels. This also helps in increasing the capacity of the existing drums. This also helps in providing the purest forms of the end products. There is reduced corrosion in the downstream areas of the product flow. When the coalescing of liquids is done efficiently, it prevents the unwanted loss of valuable products like glycol, amine, and other catalysts. Because of these manifold advantages, a liquid-liquid coalescing system is very widely used in several factories across the globe. In the area of compressed air purification, coalescing filters are used to separate liquid water and oil from compressed air using a coalescing effective.

Last but not least, it would be best to contact the right manufacturer to get the right system in place. But before that one must consider the requirement first so as to ensure the right purchase and installation.