Three Mactenn (a sister company of Macawber Engineering Inc. in the U.S.) dense-phase pneumatic conveying systems were supplied to convey bed ash between 5t/h for the two smaller conveying systems and 56t/h for the larger system 3. Material transfer distances are between 48.158 m and 70.104 m. The ash systems use 2 x 0.113 cubic meter vessels with 101.6 mm pipe lines and system 3 uses a 0.8495 cubic meter vessel on a 254 mm pipe line.

All dense-phase pneumatic conveying systems are located under feed hoppers with start and stop controlled in automatic by the feed hopper and silo reception level probes to maintain empty feed hoppers and full reception silos. System 1 is used on the Economizer line with a water cooled top plate and dome filling component to withstand the high temperatures. System 2 and 3 are standard in that no additional equipment is required to handle high temperature up to 198.9°C material temperature.

Other MultiAshflo (known as Ashveyor in U.S.) equipment supplied were switch type diverter valves, isolation high temperature knife gate valves, wear resistant bends and end diverters placed on top of the reception silos. System 3 conveyed the ash material directly in to the fluid bed of the boiler.

MATERIAL CHARACTERISTICS

Bed Ash 0.1016 mm to 2.032 mm
Bulk Density 69 lb/ft³
Temperature 198.9 °C to 348.9°C
Moisture Content Dry
Condition Free Flowing

SYSTEM OBJECTIVES

  1. Dense phase low velocity conveying
  2. Reliable operation.

SYSTEM PERFORMANCE

Transfer Capacity 5 – 56t/h
Conveying Distance 48.1584 m to 70.104 m
Reception Points 1 feed and 1 reception point per system.

IMPROVEMENTS ACHIEVED

  1. Increased transfer rate.
  2. Reduced compressed air requirements.
  3. Spillage free conveying.
Spillage-Free Bed Ash Pneumatic Conveying Systems