As you know, we are a company dedicated to compressed air and everything connected with it. One of our finest, most demanding and most complex projects so far was a nitrogen generation station for a well-known domestic coffee producer. The client’s requirement was crystal clear and precise from the start, and left no room for improvisation or deviation:
“We need 260 m³/h of nitrogen at 99.9% purity in all weather conditions! Can you commit to that in a contract and accept all the consequences if the agreed result is not achieved?”
Anyone familiar with compressed air, from production to use on site, knows exactly what they meant. Apart from the pressure we compress it to, the properties of compressed air change with ambient conditions – temperature, the amount of moisture it can carry, the amount of contaminant particles. So our task was to deliver exactly what the client asked for on their production line, regardless of the “world around us” – that is, regardless of the weather.
We all know that even though we are in a continental climate, for at least 7–10 days a year we have so-called “tropical conditions”, with temperatures above 40 °C and relative humidity of up to 80%. Those 10 “tropical” days can cause real chaos in nitrogen generation, resulting in poor purity readings, poor product quality, scrap, costs and losses.
01What we were working with
First, the world around us – climate conditions we cannot influence, however much we would like to. Ambient air is the input element, and the conditions that matter are its temperature, moisture content and the amount of solid particles it carries.
The moment the compressor draws in the air, the situation passes into our responsibility and control. How? We know the output: the amount of nitrogen required and its purity. We know that compression raises the inlet air temperature by about 10 °C. We know the reference conditions every component in the installation needs. And the temperature of the compressed air is the common denominator of all input parameters for optimal performance. So the solution presented itself: start at the source of the potential cause of unwanted results.
02The solution
- Compressor: maximum permitted inlet air temperature 45 °C. Knowing that compression would raise it to 55 °C, we had an “alarm” right at the source – we could not cool the compressed air enough for optimal conditions at the refrigeration dryer inlet.
- What was needed: an aftercooler, i.e. additional first-stage cooling of the compressed air. Since ambient air is already too warm in extreme conditions, we ruled out an air-cooled aftercooler and chose a water-cooled aftercooler with water-glycol.
- How to provide water cooling: a closed loop with a water-cooled chiller, which lets us define the inlet temperature and set the desired outlet temperature of the compressed air – ensuring optimal conditions for the refrigeration dryers even in extreme ambient conditions.
As a result, we ensured the optimal compressed air temperature at the nitrogen generator inlet and the promised nitrogen volume and purity. Temperature was solved by this set-up, and any contaminant particles the compressor draws in from the surroundings were dealt with by Class 0 filtration (the strictest under ISO 8573-1).
The result of conditioning the conditions: flawless system operation for 2 years now! Yes, it took a lot of analysis, a lot of action and a lot of equipment – but the positive result is there, and that is what counts.
03Conditioning the conditions – in life too
Knowing how to condition the conditions in a compressor room is useful to every compressed air user, but conditioning the conditions in everyday life is just as unavoidable if we want to move forward towards our goals.
Conditioning the conditions during the pandemic: the result we want is to prevent the rapid spread of the virus, to avoid the collapse of the health system and give every current and potential patient the care they deserve. The way to achieve it: social distancing, since the virus spreads by droplets from person to person. What does the result depend on? On us… only on us!
Stay well…
