Particle processing

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein processing the particles comprises controlling gas-solid contact time by adjusting the spacing and size of gas bubbles, so that the linear span of the area-based distributions of the bubble size and the horizontal spacing between adjacent bubbles in the fluidized bed may be less than 1.5 and 1.75, respectively.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein a time averaged exchange rate between an emulsion phase of the bed and a bubble phase of the bed is between 0.1 and 500 litressolid particles/m2s.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein processing the particles comprises controlling the stress experienced by each particle by adjusting the spacing between and size of gas bubbles, so that the standard deviation of stress experienced by each particle in the bed is less than 50% of the median stress.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein the bed is provided with one or more baffles that divide the bed into a plurality of vertical particle bed portions, wherein each bed portion has a thickness, normal to the baffle and less than twice the horizontal spacing between bubbles.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• introducing solid particles to the bed while the bed is fluidized, and/or recovering processed particles from the bed while the bed is fluidized,
• wherein the fluidized bed is rectangular, and solid particles are added in a central region of the fluidized bed, and/or lateral positions following the advection of particles from the centre outwards and/or processed particles are recovered at an edge region of the fluidized bed.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein processing particles comprises adjusting a gas flow to manipulate the flow regime of bubbles in the fluidized bed to vary the conditions of particle processing;
• and wherein processing particles further comprises a first phase with a first set of process parameters that cause a first configuration of the fluidized bed, and a subsequent second phase with a second set of process parameters that cause a second configuration of the fluidized bed that is different from the first configuration.

A method of operating a gas-solid fluidized bed, comprising:

• flowing a pulsating gas flow upwards through a bed of solid particles from a distributor to cause a dynamically structured bubble flow;
• and
• processing particles using the fluidized bed,
• wherein the gas flow is pulsed at a frequency f between 1.5 and 5 times the natural frequency fn of the bed, and the pulsed gas flow has a minimum superficial gas velocity that is below the minimum fluidization velocity, and a maximum superficial gas velocity that is above the minimum fluidization velocity.