Nature protection technologies

1.2.2. Technologies of ash collecting at TPPs

Part 1. AIR PROTECTION FROM POWER INDUSTRY EMISSIONS

1.2. Ash collecting at TPPs

1.2.2. Fly ash collecting technologies at TPPs

1.2.2.1. Inertial ash collectors

Prokhorov V.B., MPEI (TU)

Cyclones are widely used as inertial ash collectors at TPPs, in which the ash is precipitated due to centrifugal forces at rotative movement of the stream.

Part 1. IR PROTECTION FROM POWER INDUSTRY EMISSIONS

1.2. Ash collecting at TPPs

1.2.2. Fly ash collecting technologies at TPPs

1.2.2.2. Fly ash scrubbers

Prokhorov V.B., MPEI (TU)

The simplest type of scrubber ash collector is a centrifugal scrubber, in which a water film runs down the wall, so the ash, separated due to inertial forces, is better removed from the scrubber into the hopper, and ash re-entrainment from the walls by the gas flow is reduced. Scrubbers have the ash collection efficiency of 0,82 ... 0,90.

Part 1. AIR PROTECTION FROM POWER INDUSTRY EMISSIONS

1.2. Ash collecting at TPPs

1.2.2. Fly ash collecting technologies at TPPs

1.2.2.3. Electrostatic precipitators

Prokhorov V.B., MPEI (TU)

Electrostatic precipitators (ESPs) are the most widely applied at TPPs as ash collectors, since they allow to clean gases from ash with an efficiency of 0,990 ... 0,998 at the hydraulic resistance of less than 200 Pa. Capital expenditures for construction of ESPs are high, as these devices are metal-intensive, require large space, are equipped with special stepping up-rectifier units of power supply.

Part 1. AIR PROTECTION FROM POWER INDUSTRY EMISSIONS

1.2. Ash collecting at TPPs

1.2.2. Fly ash collecting technologies at TPPs

1.2.2.4. Fabric dust collectors

Prokhorov V.B., MPEI (TU)

In fabric filters filtering is performed through a flexible fabric, made from thin fibers of 100 ... 300 mm in diameter. The filters have a cylindrical shape and are called bag filters. Using fabric filters a high dust collecting efficiency - up to 99,9% can be reached.