CD Desiccant Dryers for High Quality Air Applications презентация

Smallest - CD 2 = 2 l/s or 4.24 cfm Largest - CD 280 = 280 l/s or 593 cfm
Units available with different PDP’s, options and control systems
All variants available in both 11 bar (159 psi) and 16 bar (232 psi) versions
All variants available 50/60 Hz and 230/110V
Various pressure approvals available - CE, ASME, DIR, SQL, UDT
A Broad & Deep Range From 2-280 l/s
Range & Sizes
Range & Sizes

Desiccant Technology
Desiccant Technology
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles

Desiccant bead
Pores
Saturated air
Air with decreased moisture content
Water molecules are transported into the pores trough diffusion.
Molecules are accumulated on the pore surface due to:
Physical binding
Chemical binding
Capillary-condensation
Desiccant Adsorption Principle
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles

Air In - 39g/0.2lbs/m³
Air Out - 0,11991g/0.000lsb/m³
Water vapor transfers to the desiccant
because…
desiccant has a greater attraction for water than air.
But:
The attraction slowly decreases as the desiccant gets wet
Meaning :
that the wet layer slowly rises up the tower, as dry desiccant is more attractive than wet desiccant. After the half cycle time, the wet layer is almost at the top of the dryer.
This means:
That, the amount of water being taken out of the air is stable, and therefore a dew point -40°C is constant from the beginning to the end of the cycle.
Also:
If the dryer vessel continues to accept air, the PDP would slowly decay. After about 90 minutes it would be around -20°C. If the PDP becomes positive, the desiccant is ruined.
Finally:
For a -70°C PDP, more water attractive desiccant is needed.
The Adsorption Process
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles

Things To Remember:
The more desiccant used, the longer the vessel can keep the desire dew point.
The dryer gives the most optimum performance when the desiccant is suited to the PDP required
In order that the dryer performance to reliable and stable, we add much more desiccant than the minimum required
Crucial Parameters
If the air temperature increases, the wet layer reaches the top more quickly.
Inlet pressure effects the dryer performance.
Because:
A desiccant bed is sized for a fixed actual volume of inlet gas, meaning the higher the pressure the more FAD can be dried
Also:
The higher the nominal PDP, the less desiccant is needed for a fixed flow
The Adsorption Process
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles
Air Out - 0,11991g/0.000lsb/m³
Air In - 39g/0.2lbs/m³

l/s
Desiccant Purging
1/2 CYCLE TIME
Equalisation
The Phases Of The Purge Process
The Purge Process
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles

Important Things To Know About Purge
The actual flow rate (not FAD) of purge air through the purge nozzle is fixed, and set to remove a fixed quantity of water from the desiccant bed.
BUT
The hotter the air into the dryer, the hotter the purge air also, meaning more water can removed by the same quantity of purge air. If a dryer is resized due to high inlet temperature, the nozzle can also be resized
The higher the pressure into the dryer the more FAD is used for purge, (fixed actual flow through nozzle) although the % of dryer capacity remains constant
The Purge Process
Desiccant Absortion
Absorption process
Absorption process
Purge Process
Purge Process
Working principles

The CD Desiccant type air dryers utilize chemicals beads, called desiccant, to adsorb water vapour from compressed air. The desiccant provides an average -40°C pressure dew point performance.
The CD dryers are configured with two pressure vessels, filled with desiccant, switching valves to direct the compressed air flow and controls for proper switching of the dryer vessels. The desiccant material is a solid adsorbent which removes water vapour by physical forces which attract water vapour to the surface of the material. Solid adsorbent materials are highly porous on a microscopic scale which provides a large surface area for adsorption. Adsorption is an exothermic process and as the drying takes place heat is released and is stored in the desiccant bed and later used in the regeneration process.
CD7-60 Working principal
CD7-65 Working
CD7-65 Working
CD65-280 Working
ICD65-280 Working
Working principles

The basic operation of a the CD dryer consists of one drying cycle and one regeneration cycle, which is continuously repeated.
For example, a 4 minute cycle consists of a 2 minute drying cycle and a 2 minute regeneration cycle. During the drying cycle, compressed air, at full pressure, flows through one desiccant vessel. As the air flows through the desiccant bed, microscopic pores on the surface of the desiccant beads "strips" the water vapor and lubricant molecules from the air, thereby reducing the relative humidity of the air. The relative humidity of the dried air is equivalent to a pressure dew point of -40°C or lower.
CD7-60 Working principal
CD7-65 Working
CD7-65 Working
CD65-280 Working
ICD65-280 Working
Working principles

CD7-60 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Purge nozzle
Build-up & Function

CD65-280 Working principal
CD7-65 Working
CD7-65 Working
CD65-280 Working
ICD65-280 Working
Working principles
CD65-280CDAnimation.exe

CD65-280 Working principal
CD65-280ICDAnimation.exe
CD7-65 Working
CD7-65 Working
CD65-280 Working
ICD65-280 Working
Working principles

CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

CD65-280 Build up & Function
Nozzle
Non Return valve
Dew Transmitter
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
Cleaning of sensor only with Aceton
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
Vessel “A” under pressure
Vessel “B” regenerating
Warning : sensor error
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
Warnings
Dewpoint Failure
No dewpoint
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
Service
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD7-65 Build up
Build-up & Function

CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

CD65-280 Build up & Function
Symptom
Possible cause
Corrective action
The dryer has not had the time to
regenerate completely.
Close the valve installed between the dryer
and the application (if permitted) and have
the desiccant regenerated.
The drain is not working correctly
Check the drain valve of the filter.
The air flow through the dryer is too
high.
Check for correct application.
The outlet pressure is too low.
Check whether the compressor provides
enough air for the application.
The PDP temperature is too high
The inlet temperature is too
high.
Check the compressor after cooler.
Dryer produce a lot of noise
Check the silencer and its fixation to
the unit.
Replace the silencer if necessary or
correct its fixation.
Insufficient air leaves the dryer
Too much purge air escapes.
Check the
condition of the solenoid valve
and replace it if necessary. Also check the
pneumatic valves and the 3
-
way valve.
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

Increase Inlet Temperature (but nothing else)
Desiccant beds become saturated more quickly
Either pressure dew point suffers or Inlet flow must be reduced.
Increase in purge air temperature means that the same amount of purge air can remove more water.
If the inlet flow to the dryer is not reduced, the desiccant becomes “extra” wet, meaning that a -40°C/F PDP is not maintained. This “extra” wetness can be removed because the purge air is also warmer and therefore has greater water holding capacity
If you de-rate the dryer due to an increased inlet temperature, there is no extra wetness in the desiccant bed. However, the purge air flow remains constant (fixed nozzle) and is warmer, meaning that it has more water removal capacity. Theoretically this means that purge flow could be reduced.
What Does This Mean…...
What Happens In Hot Ambients
CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

Decrease Inlet Pressure (but nothing else)
The capacity of a dryer is based on the actual flow at inlet, not FAD. Therefore the lower the inlet pressure the less FAD can be processed
The purge nozzle allows a fixed actual flow, regardless of pressure. This means that as pressure decreases the amount of purge available, once expanded to atmospheric pressure, is less.
If the FAD inlet flow is not decreased, the actual volume of air going through the dryer will increase. Therefore the speed of the air through the dryer also increases above the nominal speed which damages the desiccant. As there is more actual air flow through the dryer, the desiccant bed becomes “extra” wet.
A lower pressure are dryer inlet also reduces the amount of purge air available, with the result that not even a normally wet bed can be regenerated. An extra wet bed will cause the dew point to crash even quicker. The dryer must be de-rated to account for this reduction in purge air.
What Does This Mean…...
What Happens In Hot Ambients
CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

Increase Required PDP (but nothing else)
When air passes through a regenerated desiccant bed, the PDP is -40°C. This is fixed due to the properties and amount of the desiccant in the vessel
The purge flow is fixed so that at nominal conditions it will remove a fixed amount of water from the desiccant bed.
If nothing else changes, increasing the PDP will not facilitate an increase in flow through the dryer. Although with a PURGED version it will increase the “waiting time” between the vessel changeover.
In the event that there is also a higher inlet temperature, an increased PDP will mean a smaller correction factor.
What Does This Mean…...
What Happens In Hot Ambients
CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

Using Correction Factors - Do’s and Don’ts
DO
Remember that for inlet temperatures greater than 50°C, you must use molecular sieve desiccant instead of activated alumina.
Take into account that to a certain degree you can balance a high dryer inlet temperature with a worse pressure dew point. That is, the “de-rating” factor does not have to be so big, if a worse PDP can be tolerated.
Remember that a dryer must be de-rated if the actual inlet pressure is likely to fall below the nominal inlet pressure.
Use the sizing program when it’s released
DON’T
Allow the inlet flow, for any model, to exceed the nominal flow
Forget that a worse PDP does not allow an increase in inlet flow, except where the inlet flow is at a higher than nominal temperature
Recalculation For HA Conditions
CD65-280 Build up & Function
CD7-65 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
CD65-280 Build up
Build-up & Function

CD7-60 Improvements
O-ring rolled in piston inlet-outlet valve
Starting from serial number AIQ 556 570
And 1x AIQ 510 874
Material of nipples change into Brass nickel plated
Between Solenoid valve and inlet base
CD7-17 :0603 5105 03 replaced by 0603 4100 17
CD24-60: 0603 4104 03 replaced by 9740 2021 44
Old : Steel
New : Nickel plated
Improvements

CD7-60 Service tools
CD24-60 for plug 1617 6181 00 (old) and 1617 6225 00 (new)
CD7-17 for plug 1617 6180 00
CD7-60
CD-60
CD7-60
CD65-280
Service

CD7-60 Service tools
Valve seat CD7-60
2903 0014 01 is for CD7-17
2903 0014 02 is for CD24-60
To protected valve seat tool
2903 0043 00 is for CD7-17
2903 0044 00 is for CD24-60
CD7-60
CD-60
CD7-60
CD65-280
Service

CD7-60 Service Kits
Service kits
CD7-60 Tools
CD-60 Tools
CD7-60 Kits
CD65-280 Kits
Service

CD65-280 Service Kits
CD65-80-100 4000Hrs 2901 1000 00
CD65-80-100 40000Hrs 2901 1001 00
CD140 4000Hrs 2901 1002 00
CD140 40000Hrs 2901 1003 00
CD170 4000Hrs 2901 1004 00
CD170 40000Hrs 2901 1005 00
CD230-280 4000Hrs 2901 0995 00
CD230-280 40000Hrs 2901 0996 00
Kit 4000Hrs consist of Silencer 1617 6164 03 2x + Filter elements DD/PD.
Kit8000Hrs consist of kit 4000Hrs + Recalibration dew point sensor ECB AII0120
Kit 40000Hrs consist of 4000Hrs kit + Dessicant
CD2 till 6 there are no kits available
Download of software can be found were you find the MKIV software
Service kits
CD7-60
CD-60
CD7-60
CD65-280
Service

Trouble shooting
1/ Dew point too high : Electrical Problem
2/ Dew point too high : Mechanical Problem
1.1 Connected Electrical ?
1.2 Check working of the solenoid
1.3 Mitchell sensor (if available)
2.1 Check the diameter of the air inlet
2.2 Check air flow over the Mirchell sensor (if available)
1.4 Check Timer card (if available)
2.3 Check all vavles
2.4 Check silencers and connections of the tubes (if available)
2.5 Check all needle valves
2.6 Check the installation on set up
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD7-280
Check if the power supply is connected
This is for the CD65-280 purge control
Check if the power supply is connected
This is for the CD65-280 standard and
CD7-60
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD7-280
The working of de solenoid can be checked to put a metal piece or srewdriver on the electrical vale .
The valve is working ( blow off air on the silencer ) if you feel some magnet with a metal piece. (see figure)
The other valve is not electrical “on”so you don’t feel a magnet
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD65-280
Check also the electrical connection , if one of the wires is grounded you can expect a bad read out
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD7-280
How to check te working of the time card :
Connect with the correct tension , one of the solenoid connnections have the same tension as the power supply , the other has no tension , after the fixed time the tension of the solenoids will switch. This is an example of 220V 50Hz
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD7-280
Check if the the right in-outlet connetion is foreseen ( for the correct figures see instruction book)
Trouble shooting
Electrical Conn
Solenoid
Mitchell Sensor
Timer Card
Connections Airinlet

Trouble shooting CD65-280
There must be a small air flow going over the sensor , you can check this with your hand hold under the tube and you will feel some air flow. ( +/-4a5L/min)
If the is no air flow a bad reading out on the electronikon can be expected
It there is to much air flow you have also to much loss air ( no warning or indication is seen on the display)
The regulation can be set by the needle valve
Trouble shooting
Flow Sensor
Valves Sensor
Silencers
Needle valves
Installation

Trouble shooting CD65-280
Valves must be open , in case on of them is closed a bad reading out of the dew point on the electronikon
Trouble shooting
Flow Sensor
Valves Sensor
Silencers
Needle valves
Installation

Trouble shooting CD7-65
Check the right connections of the tubes ( see intrustion munual)
Ckeck the silencers on dirt inside , when the silencers are blocked a lower dew point can be the cause)
Trouble shooting
Flow Sensor
Valves Sensor
Silencers
Needle valves
Installation

Trouble shooting CD65-280
Check the needle valves , a closed needle valve means no switching of the towers the exhaust valve is blocked.
Regulate the needle valve as follows , turn with screw driver the screw complete to the right (closed) then 2 turns back to the left , blocked the counter screw and ½ turn to the left
A complete open valve give a full pressure on the exhaust valve and open immediately the exhaust valve , the regulation is to slow down the open time
Trouble shooting
Flow Sensor
Valves Sensor
Silencers
Needle valves
Installation