Discharge and pneumatic conveying of fluorinated derivatives

Processed powders: fluorinated derivatives: ammonium bifluoride, sodium fluoride, potassium fluoride, magnesia

Ethanol production

This customer is a specialist in the processing of oilseeds for biofuel processes.
his new plant must introduce fluorine derivatives into its production and has therefore been forced to design a dedicated production skid. These ingredients are delivered in bags.

Objectives of the project
Production requirements: once a week, fill a 3,000-litre buffer hopper with dry bulk material. This buffer hopper itself feeds a 1,200-litre dilution tank, while retaining a high concentration of this bulk material in the water.
This concentrate is diluted in the final phase in a 10,000-litre tank with a simple suspension of the dissolved solution.
This batch manufacturing process makes it easier to dilute fluorinated derivatives, due to the small size of the first dilution tank, and avoids investing in a very powerful and therefore expensive industrial mixing system.
The major imperative was to minimize the dimensions of the system, risks for operators and to respect the process demands.

In order to limit operator tiredness and poor posture, Palamatic Process has installed a bag manipulator to handle bags from 25 to 50 kg without any effort (weightlessness) up to the discharge point.
Once the bag is placed on the screen of the manual bag emptying station, the operator closes the door of this station. A blade operated by a cylinder then cuts the bag to its width, the operator opens the door and finishes emptying the bag manually without having to use a cutting tool.
Once the bag is emptied, the operator then throws it directly into the adjacent bag compactor without having released this potentially polluting container into the atmosphere because the fines tend to fly away when released into the atmosphere.
The empty bags are extruded directly into a polyethylene sheath that ensures the containment and compaction.

The bottom of the discharge station is equiped with a flat-bottomed anti-bridging system that itself feeds a pneumatic conveying in the dense vacuum phase. The advantage of this technology is that it allows the bulk material to be elevated at a lower cost and at a lower speed (limiting degradation).
The pneumatic conveying system is supplied by an air/product separation cyclone which is installed directly with a flexible connector on the first 3,000 liters buffer hopper.
This hopper, mounted on load cells, is provided with a dehydration system in order to limit the material's moisture recovery as much as possible.
In the lower part of this hopper, a flat-bottomed anti-bridging device is used to feed a conveying screw that feeds the dispersion tank used to produce the concentrate. The dosing is carried out by the servo control of the screw and the anti-bridging device with the load cells.
Dispersion is carried out by a profiled helix shaft which allows the dry bulk material to dissolve rapidly at room temperature. The HDPE manufacturing tank (avoiding any risk of corrosion) is supplied with an anti-vortex system.
The resulting concentrate (which was therefore obtained in masked time) is then vacuumed on demand of the final liquid storage tank.

Results
This system allows, by its design, to make a long-lasting buffer before a dilution phase and therefore avoids a disproportionate investment in view of the small daily quantities of mixture used.