General Process Information
The coal goes through a moderate grinding process and then is stored in a coal bunker. afterwards the coal is typically delivered to a power plant via rail or conveyor belt.
The coal is transported by conveyor and tripper cars to coal hoppers / silos.
These hoppers feed ball mills which is turn fedd the pulverized coal to the boilers.
There will be at least one hopper for each boiler.
Typically there are two boilers per unit. If a coal hopper were to be completely empty, the boiler would need to be shut down.
Limestone is utilized as an ingredient for Sulfur removal in the scrubber and is also utilized as a blending agent with coal in fluidized bed boilers.
Both the pollution control and fluidized bed applications are viewed as important applications. The light ash that comes off the top of the boiler is captured in fly ash hoppers.
The contents of the fly ash hopper are pneumatically conveyed to a fly ash storage silo. The silo is emptied to trucks that then haul the fly ash off for use in other applications.
The heavy ash that comes off the bottom of the boiler is collected in an underwater vessel below the boiler. This vessel is emptied to the bottom ash storage vessel. The bottom ash storage vessel allows the bottom ash to be dewatered and then stored.
The fly ash storage vessel is emptied to trucks that then haul the bottom ash off for use in other applications. The material is considered hazardous waste.
In all stages of the above process it is highly important to accurately control the content of the stored material to allow the power plant to operate continuously. prevent over spilling and assure continuous feed to the furnace.
Dust, filling noises, hot temperature caracterize the entire process in addition to the low density in the fly ash state.
APM Technology is the best fit and the optimal solution for the Coal Fired Power Plant :
The 3DLevelScanner is unaffected by the type of materials being stored, avoiding the need for special calibration, or by environmental conditions, such as dust, filling “noise”, humidity, or temperature.
Three factors combine to make the technology an innovative one and the best-of-class solution for accurate measurement of bulk solids, particularly those in dusty environments:
1. Low frequency of transmitted signals (under 4 kHz)
2. A 3-antenna system that measures not only elapsed time between transmission and receipt of acoustic echoes but also the phase between the echoes
3. Proprietary algorithms enabling precise 3-D mapping of the contents inside the silo or storage bin