Dry ash handling systems
During coal combustion at thermal power plants, ash, or mineral residues of fuel combustion process, is formed. Therefore, temporary or continuous disposal and transfer of ash outside the power plant is necessary. Powerz designs up-to-date pneumatic ash handling, flue ash and dry ash handling systems. We offer comprehensive design of process flow charts and automation systems, as well as delivery of equipment on a turnkey basis. We are currently putting in place several projects involving installation of dry ash handling systems in Europe and Far East.
Basic equipment of dry ash handling systems
Pneumatic chamber pump
One tank of a pneumatic chamber pump is located before each ash discharge line. All pump tanks are connected to a single transmission pipeline and are discharged simultaneously. Operating pressure used for transmission is approximately 2 bar. To provide this pressure, a compressor with a drive on each electric filter (container-type with adsorption dehumidifier, which prevents the formation of condensate in pipelines) and a set of fine cleaning air filters are installed. Closing valves are located over each tank of each pressure vessel.
Silo storage system
Silo storage systems are reservoirs made of metal or reinforced concrete; their capacity is selected based on the amount of ash retained by filters. Reservoirs are equipped with ladders, operating platforms and facilities for installing the equipment (located in the bottom part of the system).
Aeration systems of silos’ bottom
Aeration of fly ash storage systems is performed at regular intervals in order to prevent ash bedding as well as during its discharge. Only 20 to 25 percent of silos’ bottom is tiled; air pressure should be 2 to 3 atm, with the flow of 0.25 m3/min per 1 m2 of aerated surface.
Silo discharge systems
Each silo has three discharge lines: dry discharge to vehicles, wet discharge to vehicles, and ash discharge to circulation stations. Aspiration hose pipe, which is a telescopic two-channel coaxial device, is used for dry discharge of ash. Bulk material is first loaded into the tank through the internal cavity of the hose pipe, and ash coming out is sucked into the internal cavity and then transported back into the silo via an individual fan, providing total absence of dusting during unloading of material. Aspiration hosepipes with individual hose filters may also be used.
Two-roll mixing unit
Horizontal flow mixer is used for ash unloading into open top vehicles. Ash is humidified to 20-25% and to a homogeneous mass. Flow of injected water depends on flow of bulk material; the latter is controlled by impact scales mounted before the mixing unit’s entrance.
Aeration-type air slide is intended for ash feed into recirculation system’s pump. Mechanism of air slide is based on mixing of various fine materials with capillary-sprayed compressed air, which transforms the material into the state of pumped liquid.
Advantages of our equipment
Powerz are a supplier of equipment which provides a full range of design and engineering services. In doing so, we use extensive experience of our partners, offering products which fulfill all operating requirements. Production cycle of our equipment is solely situated in Russia, and this equipment is manufactured in accordance with Russian GOST and OST standards as well as international quality standards.
All equipment is licensed and certified.
Gallery of production sites