Pressure drop and controlling system pressure

As you may know maintaining pressure drop is important way to make the compressed air system energy efficient.

Pressure drop is a difference between pressure after the compressor and presure that comes to the actual user of the compressed air, for example, the laser cutting machine. Pressure drop is thus undesirable and is an indirect cost for your cleint that results in higher electricity bill and higher production price of the end goods.

It occurs due to improper sizing of air treatment equipment as well as due to insufficient maintenance of the equipment. The rule of good practice say that properly designed system should have a pressure drop less than 10% of the compressor’s discharge pressure, measured from the receiver tank output to the user (machine or tool).
 
The problem with pressure drop is even worse during times when the airflow and temperature are at highest. With the higher temperatures of the summer months and increased humidity, more water comes into compressed air system. Filters are affected by this additional moisture and when pressure drop rises compressor running costs are higher. Therefore, it is advisable to replace the filter elements at that time.

How can Omega Air products contribute to lower pressure drop?

SELECT CORRECT FILTERS AND SEPARATORS 
  • When selecting filters please remember that they will gradually saturate. For your convenience we provide the information about pressure drop when the element is dry and when is wet. Please adress to our product datasheets for this information. 
  • Pressure drop of our 3 micron cartridges marked P or /P is just 10 mbar in dry condition making it very effective and energy saving.
MAINTAIN FILTERING ANG DRYING LEVEL
  • Wet conditions are undesirable for compressed air system. Not only corrosion but also higher pressure drop appears. Thoughtful choice of drying technology furthemost depends on the required dew point. For many applications refregirant dryer is enough.
  • OMD series pressure drop starts at 150 mbar.
  • For stable quality and low cost filtration it is recommended to replace filter element after 12 month in operation (6 months for A element) or when pressure drop exceeds 350 mbar.

Altogether the information above is not new, but here is the animation for you to see the clear picture. The animation demonstrates how the pressure drop is developing when the cartridges are clogged. 
 

Below is the example of calculation of savings that can be done if the cartridges are changed at high pressure drop of 500 mbar. How much will you save in 1 year?
 
 COMPRESSOR
90
Kw
 
 TOTAL POWER CONSUMPTION
108
Kw
 
 COMPRESSOR OUTPUT @ 7,5barg
918
Nm3/h
 
 ELECTRICITY COST
0,1
€/kWh 
 COMPRESSED AIR COST0,011764706
€/Nm3
 
 OPERATING HOURS
5000
h
 
 ANNUAL COMPRESSED AIR COSTS
54000
€
 
 
ENERGY LOSSES 
 Pressure drop on filters R S   
 *pressure drop in saturated state is around 500 mbar
1000
mbar
 
 Advised pressure drop change at 350 mbar, R S
700
mbar
 
 
Pressure drop on filters R S
*pressure drop of new R grade is 40 mbar, of new S stage is 190 mbar
  230 
 
mbar
 
 
ENERGY LOSSES COSTS
 Pressure drop on filters R S
5400
€/y
 
 Pressure drop on filter at 350 mbar
3780
€/y
 
 Pressure drop on new filter elements
1242
€/y
 
 Difference in cost of pressure drop 500/350 per element
1620
€/y
 
 Difference in cost of operation of the new elements compared to 350 mbar per element 
1396
€/y
 
 General difference in costs of changing the new element
3016
€/y
 
 Gross Price of the filter element 51090 R S
260
€/y
 
 Saving per 2 filters R S
2756
€/y