Back mixing device for pneumatic conveying systems
View Patent ↗The present application provides a back mixing device for use with a pneumatically conveyed flow of solids having a varying flow rate. The back mixing device may include a nozzle, a chamber in communication with the nozzle, and an exit. The chamber may include an expanded area leading to a restriction such that the chamber creates a recirculation pattern in the flow of solids so as to smooth the varying flow rate though the back mixing device.
1. A pneumatic conveying system, comprising:
a source of coal;
a solids feeder in communication with and positioned downstream of the source of coal;
a high pressure feed Vessel in communication with and positioned downstream of the solids feeder;
a flow of conveying gas in communication with the high pressure feed vessel and a bypass line for bypassing the high pressure feed vessel;
a flow meter in communication with and positioned downstream of the high pressure feed vessel;
a first back mixing device in communication with and positioned between the high pressure feed vessel and the flow meter;
a gasifier in communication with and positioned downstream of the flow meter, and
a second back mixing device in communication with and positioned between the flow meter and the gasifier.
2. The pneumatic conveying system of claim 1 , wherein the solids feeder comprises a rotary, converging channel solids pressurizing and metering device.
3. The pneumatic conveying system of claim 1 , wherein the high pressure feed vessel comprises a flow of a pressure controlling gas and a flow of a fluidizing gas.
4. The pneumatic conveying system of claim 1 , further comprising a controller in communication with the flow meter and the solids feeder.
5. The pneumatic conveying system of claim 1 , wherein the first and second back mixing devices comprise a chamber with an expanded area leading to a restriction.
6. The pneumatic conveying system of claim 1 , wherein the first and second back mixing devices comprise a plurality of chambers.