Donaldson DC 0020 AB-0850 AB Buran Air Dryer with Filters

A refrigeration dryer with the pre- and after-filter already inside

The Donaldson Buran DC 0020 AB to DC 0850 AB is a refrigerated compressed air dryer sold as a complete purification package. Inside the cabinet sit a V-grade pre-filter that protects the dryer from contamination and a UltraPleat M after-filter that removes oil aerosols and particles, plus a level-controlled UFM-D condensate drain at the heat exchanger, so no extra pipework or separate filter housings are required.

Seventeen sizes serve intake flows from 20 to 850 m3/h at ISO 7183 conditions. Operating pressure is 2 to 16 bar(g) up to DC 0085 AB and 2 to 14 bar(g) for DC 0105 AB and larger, and the pressure dew point is +3 C at the nominal conditions.

Technical specifications

Sizes, filters and pressure drop

• DC 0020 AB: Flow m3/h 20; Pressure drop bar incl. filters 0.04; Cooling air m3/h 200; Power kW 0.14; Filter housing and element DF-0120, M 0070
• DC 0065 AB: Flow m3/h 65; Pressure drop bar incl. filters 0.13; Cooling air m3/h 300; Power kW 0.24; Filter housing and element DF-0120, M 0070
• DC 0125 AB: Flow m3/h 125; Pressure drop bar incl. filters 0.39; Cooling air m3/h 300; Power kW 0.45; Filter housing and element DF-0120, M 0120
• DC 0225 AB: Flow m3/h 225; Pressure drop bar incl. filters 0.18; Cooling air m3/h 380; Power kW 0.76; Filter housing and element DF-0320, M 0210
• DC 0360 AB: Flow m3/h 360; Pressure drop bar incl. filters 0.49; Cooling air m3/h 450; Power kW 0.89; Filter housing and element DF-0320, M 0320
• DC 0550 AB: Flow m3/h 550; Pressure drop bar incl. filters 0.15; Cooling air m3/h 1,900; Power kW 1.11; Filter housing and element DF-0750, M 0600
• DC 0850 AB: Flow m3/h 850; Pressure drop bar incl. filters 0.33; Cooling air m3/h 3,300; Power kW 1.70; Filter housing and element DF-0750, M 0750

The pressure drop in the sheet is quoted including the pre- and after-filter.

Selecting a size

Correct the compressor intake flow with the sheet factors: operating pressure (0.49 at 2 bar(g), 1.00 at 7 bar(g), 1.33 at 16 bar(g)), air inlet temperature (1.20 at 25 C down to 0.37 at 70 C), cooling air temperature (1.00 at 25 C to 0.60 at 50 C) and pressure dew point (1.00 at +3 C to 1.37 at +10 C). The sheet example takes 100 m3/h intake at 40 C inlet, 35 C cooling air, 9 bar and +3 C dew point, multiplies 0.88 x 1.06 x 0.94 x 1.00, and arrives at 114 m3/h and DC 0125 AB.

Typical use is central compressed air purification where dry, oil-free and particle-free air is wanted, and paint shop air in the automotive industry. In overload the dryer only switches off above a dew point of +20 C.

Key features of the Buran DC AB series

• Complete treatment in one cabinet: pre-filtration, drying, after-filtration and condensate removal are combined, which shortens installation time and reduces the number of joints in the air line.
• Protected heat exchanger: the V-grade pre-filter keeps solid particles and bulk contamination out of the aluminium heat exchanger, helping it stay clean and efficient.
• Oil aerosol removal downstream: the UltraPleat M after-filter cleans the dried air before it reaches the distribution network.
• Level-controlled drain: the UFM-D drain discharges condensate only when it has collected, avoiding the compressed air losses of timer-controlled drains.
• Informative controller: dew point indication, operating hours and alarm displays, plus a potential-free error contact for connection to a building or plant control system.

Selecting a size for real operating conditions

The nominal flows in the table refer to ISO 7183 reference conditions. In practice the capacity of any refrigeration dryer falls as inlet air temperature and ambient temperature rise, and increases slightly with higher operating pressure. Donaldson publishes correction factors for these conditions in the product documentation. To choose a size, take the compressor free air delivery, apply the correction factors for the worst summer condition at the site, and select the model whose corrected capacity still covers the demand.

Ambient temperature is critical in the Gulf region. The dryer is rated up to the upper ambient limit shown in the specifications, but compressor rooms without adequate ventilation can exceed this in summer. A well-ventilated room, ducting of warm cooling air away from the dryer and an aftercooler on the compressor all help the dryer achieve its rated dew point.

Pressure drop and energy

Every bar of pressure drop in the treatment line has to be made up by the compressor. The table shows the pressure drop including filters for each size; choosing a model with some margin, rather than one running at its limit, generally reduces pressure loss and protects the dew point when demand peaks.

Installation and service

Install the dryer downstream of the compressor and air receiver, on a level floor, with free space around the cabinet for cooling air and service access. Provide a bypass line with isolation valves so the dryer can be serviced without stopping the plant. Lead the condensate drain to an oil-water separator rather than directly to the drain, as required by environmental rules in most GCC countries.

Routine service includes replacing the V and M filter elements at the intervals Donaldson recommends or when the differential pressure indicates, checking the drain for correct operation, and cleaning the condenser fins so that cooling air passes freely. Dust in compressor rooms builds up quickly on condensers and reduces the dryer’s performance on hot days.

Typical applications in Oman and the GCC

The range covers small workshop compressors through to central plant air systems. Typical users include manufacturing plants, food and beverage packaging, pharmaceutical secondary packaging, automotive workshops, instrument air in utility plants, and pneumatic conveying where moisture would cause blockages or corrosion.

What to include in an RFQ

• Required dryer model, or compressor free air delivery and operating pressure.
• Maximum ambient temperature in the compressor room and inlet air temperature.
• Power supply voltage and frequency at site.
• Required air quality class or dew point.
• Spare filter elements and drain service kits needed for the first year.

Documents and quotation

Seven Star LLC can quote DC 0020 AB-0850 AB to order. Use Donaldson Buran DC 0020 AB to DC 0850 AB refrigeration dryer data sheet (F119003, 06/2018) (attached) to confirm the intake flow, working pressure and ambient temperature, then contact us. Similar equipment: Compressors.