All the Things we Dry

When drying wet objects, whether after wet cleaning carpet and upholstery or in a flooded structure, there are a couple things that must happen.


1. Extract the Excess Water (liquid)

2. Change the Liquid to a Vapor - Evaporate   energy 


The 1st step is critical, no matter what or why something is wet. Carpet and upholstery, that was just wet cleaned, or a flooded structure, extraction is the fastest way to get rid of the moisture. There are many ways to extract , the bottom line being, extract as much as possible. Don’t leave a lot to evaporate. It is a WHOLE LOT slower than extraction.

The 2nd step is to cause evaporation.


Free or “surface” water is relatively easy. It responds well to airflow. The molecules are separated and wind energy gets to the vapor molecules causing relatively fast evaporation.


Bound water is the moisture “in” the molecular structure of the wet item. This is harder to reach. The best energy for this, harder to reach, moisture is heat. Heat makes molecules move at higher speeds. Temperature is the measure of that speed. The more speed, the more vapor pressure and the more escaping vapor molecules from the “hold” the drop has on them. We now have single vapor molecules in the surrounding space……vapor. 


An example of surface moisture that dries quickly is a micro fiber polyester fabric. Polyester is relatively non-absorbent. It can be very heavy from all the liquid “between the thousands of micro fibers”, not “in” the fibers. Air flow causes micro fiber to dry surprisingly fast. It is full of surface moisture that responds well to wind energy. So, in this case, increase airflow..... quicker drying.

An example of bound, or liquid “in” the fiber, is cotton jacquard. This thick fabric absorbs lots of water. The liquid is “in” the fiber. Air flow has much less affect on it, when attempting to dry. Heated air flow applied to this fabric (test for shrinking) will cause much faster evaporation than just airflow. More airflow here.....better evaporation, but not, nearly, as much as you will get by combining heat, with it.

The idea, when cleaning upholstery is to get it dry ASAP, before bad things happen. You can, sometimes, dry past potential problems getting the item dry fast.


The same holds true when drying flooded structures. Surface water responds well to air flow while bound water, the moisture "in" the structure of the wet item, does not. Heat “energy” is a much more effective option. It gets into the vapor molecules better than air flow and makes the escape of the vapor molecule, from the drop, MUCH faster.

Heat is something that other industries have been using for decades. This includes Shaw Carpet Mill, which dries it's wet carpet, during production, in an oven. The cleaning and restoration industry has missed some of its benefit, until recently.


If you need to dry something, within a certain time frame……put some heat on it!


                MAKE MONEY!


                Dennis Klager
                IICRC Instructor






Copyright 2012 by Dennis Klager