Bag dumping and pneumatic conveying of activated carbon and lime

Powder processed: activated carbon and lime (with a respective bulk density of 0.5 ton/m³ and 0.6 ton/m³)

Drinking water filtration

Subsidiary specialized in public works and construction.

The customer requires a dense phase pressure conveying, at a rate of 15 tons per hour, to convey activated carbon and lime from an automatic bag discharging station Varislit® to storage silos.

Raw materials are delivered in 25 kg paper bags and are deconditioned by means of the bag automatic discharging unit VARISLIT® that is connected to an inclined belt conveyor. The operator comes to position the bag on the belt conveyor that conveys the bag to the deconditioning area.

This automatic bag discharging station Varislit® allows fast and dust-free bag emptying and operates at a rate of 6 to 12 bags per minute. The double-blade rotary system allows large bags to be processed with a high emptying rate. The entire mechanics are placed outside to avoid any contact with the processed material.

The discharged material falls into a hopper that is connected to two Maxflow® MF airlocks, a dense phase pressure conveying pneumatic conveying that operates in dense phase pressure, which then conveys it to eight storage silos. As the feeding source is unique (Varislit®), only one powder can be conveyed at a time. To change the type of powder, the main parameters to be modified are: the general compressed air supply pressure, the selection of storage silos to be filled and their associated blower lines (not to mention cutting off the supply to the others).

The dense phase pneumatic conveying system is suitable for very abrasive bulk materials. This tank is fitted with a double jacket and a special outlet bend that allows the bulk material to be gently fed into the conveying pipe.

The pressure vessel is filled from the opening of the supply headset valve and the vent line. At the end of the time-controlled filling, the valve closes and the airlock is sealed by closing the vent line and pressurizing the seat of the headset valve. Air is introduced into the pressure vessel in a controlled way to evacuate the bulk material. When the loading chamber is empty, a level detector in the lower part signals it, the compressed air is cut off and the bulk materials stops in the conveying line. Before refilling the Maxflow® conveying airlock, the contained air is discharged through a special vent valve.

The storage silos have a capacity of 150 m³ and are located outside the plant.

Metal storage silos are used for the contained storage of high-density bulk materials. They are composed of a dust filter, an expansion tank, a valve or a level probe to control the quantity contained.