Depending on customer and individual requirements, we specialise in storing combustible dusts such as pulverised lignite.
Carbotechnik silo systems are the most economical solution for storing pulverised lignite in compliance with the strict ATEX safety standards. The technical safety recommendations from Rheinbraun and Vattenfall Europe are also considered during design of the silo.
Silo equipment for explosion hazard areas according to ATEX:
General description of pulverised lignite silos:
A coal dust fired burner on a boiler system or a hot gas generator is equipped with a coal dust silo, in order to provide the dosing system and thus the burner with a continuous supply of fuel.
The silo, with a nominal capacity of up to 3000 m^3, is designed to be shock pressure resistant and is equipped with a pressure relief system (e.g. blowback flap or bursting disc). The size of the silo primarily depends on the the period over which it must be possible to supply the system from the silo.
The dust is delivered with a silo truck (road or rail transport) and blown into the silo system pneumatically. The conveying air is monitored and passed through a cooler. Operation of the downstream systems (e.g. dosing system and burner) can continue without a problem during the loading process.
An external filter with compressed air cleaning system is installed on the roof of the silo. It serves to remove dust from the carrying air which is generated during loading of the silo. This filter can also be used to dedust the fluidisation air if a separate dosing system filter isn't installed.
The silo outlet (silo cone) is designed so that even the pulverised lignite with the poorest flow characteristics can be unloaded without a problem. The outlet design is geometrically optimised, and compressed air nozzles are also installed in the cone to promote the flow of material for improved unloading (loosening of the lignite).
The silo is designed with a supporting base frame. This is where, for example, the Carbotechnik dosing system and all required unloading and shut-off systems are installed. A rotary feeder is used to unload the pulverised lignite. Gates with actuators (electrical, pneumatic, hand wheel) are provided in order to be able to close of the silo for maintenance purposes and the like.
The silo fill level is monitored by level sensors and/or continuous measurement. Overfilling is prevented and a need for refilling is indicated.
Several temperature sensors and, if necessary, a CO measurement system are also installed as safety systems, in order to be able to detect a smouldering fire in the silo as quickly as possible so that suitable countermeasures (e.g. inertisation) can be initiated.
Design principle of a 120 m³ pulverised lignite silo