In the compressed air and gas industry, there are many uses for dryers and dehydration applications that are unique. Very rarely are there two applications with the exact same conditions or specifications, unless there is a design for such a use and it is to be repeated. Recently I came across a customer that was using a standard dryer downstream of their air compressor. It was installed in a heated building, with our Dry-O-Lite desiccant and sized accordingly for their applications. They were having terrible freeze ups with the lower winter temperatures and were losing production time because of it. They called me and asked me to come to their site, since the system was setup as recommended and still causing issues.
Upon arrival to the customer site, I verified the installation of the dryer and filters and proceeded to ask questions about where the system was freezing. Here comes the unique part, the compressor was in a silo room, about 400 ft from the end point of where they were having freeze ups. They were transporting the air along a large outdoor conveyor, to the out building to run gates and mixing valves, that were pneumatically operated. The dryer was lowering the dew point and drying the air, but not enough to compensate for the ambient temperature outside. There was a cooling effect going on that was dropping liquid water out of the air in the lines. Not abnormal, but when the liquid started to run downhill, with the travel of the conveyor, the airlines come up vertically into the mixing valve manifold, which caused a bad freeze point. Anywhere compressed air slows in velocity, as in an elbow or tee, or any orifice that causes a change in direction, the liquid in the air will freeze.
So after determining the problem, we began talking about the solutions. An easy answer was to change to one of our better grade of desiccants and lower the dew point even more. After talking over with them on the demand of the dryer, we found that in the winter they have very light requirements for the air and running the better grade was not cost effective all year. The summer months they don’t notice an issue, because the ambient temperature is higher and will not condense liquid out of the air. They wanted to continue using the Dry-O-Lite, due the cost of the desiccant and they already had the approval to purchase the item. So how would we fix this issue, using the same desiccant grade and the same conditions?
Use the ambient outside air to our advantage and install the dryer outside. In the gas industry, this is done all the time. If there is a heated building and a pad outside…. You install the dryer outside to use the cooling effects of ambient air to lower the dew point even further. Running air through the dryer outside, lowers the dew point low enough to not condense liquid out of the air, until the air is used at the manifold without freeze ups.
Single tower deliquescent dryers, with our several grades of desiccant, can meet almost any application. With the understanding of the application, many solutions can be reached. If you think, your application isn’t a good fit, give us a call or schedule a visit. There may be a simple solution, that can save valuable downtime and system damage from happening to your compressed air or natural gas applications.
Ask the Compressed Air Experts, call us at 1-800-840-9906 today!