The importance of dry and clean Compressed air
In nearly all areas of the industry compressed air is one of the indispensable working medias. The appli- cation as working, conveying, measuring, control and regulating air is just as self-evident as the appli- cation in the process technology. The atmospheric inlet air of the compressor contains harmful sub- stances and impurities. Moisture in the form of vapour is condensed out into the compressed air network. This causes expensive damages and a loss in quality. Therefore processing concepts con- sisting of filtration and drying are an integral part of every compressed air application. The drying meth- od is determined by the application. Where very low residual moisture is a requirement respectively for pressure dewpoints below 0 °C, adsorption drying is applied.
System Construction from a Single Source
Donaldson plans, designs and manufactures com- plete solutions that are tailored to individual cus- tomer’s needs. Due to the close link between technical design and manufacture, customized systems arise from a single source for the benefit of customers. Particular emphasis is placed on the ease of maintenance, by incorporating accessibility of all wearing parts in the design.
Choice of Heat Regenerated adsorption dryers
Adsorption Dryer
Climate Conditions Moderate Subtropical Tropical
Moderate Moderate Moderate Subtropical Tropical
Energy-savings Zero Purge Zero Purge Zero Purge
Regeneration • Desorption in counter current flow to the adsorption direction with externally heated blower air
- Cooling in counter cur- rent flow with partial flow (2 %) of the already dried compressed air
- Desorption in co- current flow to the adsorption direction with externally hea- ted blower air
- Cooling by blower air
- Desorption in coun- ter current flow to the adsorption direc- tion with externally heated blower air
- Cooling by blower air
- Desorption in coun- ter current flow to the adsorption direc- tion with externally heated blower air
- Closed-loop cycle (Loop Version)
adsorption dryer HRS
The desorption and cooling in the HRS system variation is also accomplished with the ambient air drawn in by the blower. Compressed air will not be used during the desorption or the cooling phase. Since the desorption occurs in counter current flow, a low energy consumption is required. The HRS is therefore the most energy efficient option.
Features and Benefits:
- Energy-saving (Zero Purge, low desorption temperature)
- Low Operating Costs
- Easy Maintenance
Energy Saving (Zero Purge)
desorption phase without consuming Compressed air: Before starting the regenerati- on, the adsorber to be regenerated is gently depres- surized. Desorption takes place in counter current flow to the adsorption direction from top to bottom with externally heated blower air. The temperature increase due to the
compression has a positive effect on the energy requirement of the downstream hea- ter. The heater heats up the blower air to the required desorption temperature. The blow- er air flows in counter current into the adsor- ber to be desorbed and evaporates the water contained in the desic- cant.
Type HRS Size 2750
pressure-Vacuum-Regeneration adsorption phase: For units of the HRS the moisture containing compressed air flows via the inlet fitting through the desiccant bed. While pass- ing the desiccant bed the water vapour is adsorbed by the hygroscopic adsorbent. The dried com- pressed air is now discharged into the compressed air network.
Cooling phase without consuming Compressed air: Up to dryer sizes 2750 the direction of rotation of the blower is switched for the cooling phase so that the ambient air is drawn through the desiccant. The cool ambient air takes up the heat from the desiccant and it is conveyed to the atmosphere. The vacuum that occurs during the suction operation
mode causes the desorption tempera- ture to drop and thus a post-desorption. The residual loading in the desiccant is reduced. A better quality is achieved with the same energy in put,
- energy can be saved while maintain- ing the same quality.
adsorption dryer HRS-L
Based on the standard HRS models, the HRS-L version is designed for processing requirements at tropical and subtropical ambient conditions. These conditions do not allow for cooling with fresh air. The characteristic feature of the HRS-L models is a closed loop cooling (Loop-Version ). A water-cooled heat exchanger cools the air stream heated by the desiccant. From there the cooling air is led back to the inlet port of the blower. Worldwide for all cli- mate zones this version offers a pressure dewpoint of -70 °C.
Tailored Customer Concepts
In decades of close collaboration with our custom- ers, we have built expertise in virtually all areas of industrial production. Donaldson therefore meets exceptional and specific customer requirements with tailored and sophisticated solution concepts.
Beyond the individual concepts, we also provide the respective services for each application
