A method in a pneumatic material conveying system, such as a waste conveying system, which conveying system comprises at least one feed point (61) of material, particularly of waste material, a material conveying pipe (100) which is connectable to the feed point (61), a separator device (20) in which the material being conveyed is separated from conveying air, and means (3) for providing a pressure difference in the conveying pipe (100) at least during the conveyance of the material. At least a part of the conveying piping (100) is connectable as a section of a circuit in which conveying air is circulated at least during the conveyance of the material and, in the method, conveying air circulation is connected, at least momentarily, to a reverse direction in relation to the normal conveying direction, at least in a section of the circuit, which section of the circuit is formed by at least a part of the conveying pipe (100), advantageously for removing a possible blockage.

Method and apparatus in pneumatic material conveying system

The invention is directed to a method and apparatus for establishing and maintaining a uniform mass flow rate of particulate solids and gas mixture from a container to a receiving reactor. A preferred embodiment utilizes an aeration tube suspended in the particulate mixture and serving as a fluidic valve to maintain a uniform mass flow rate. A portion of the aeration gaseous fluid may be directed upward in aid of such flow.

Aeration tube discharge control device

This invention relates to a method and apparatus for delivering particulate solids in a stream of gas to a selected delivery point. The particulate solids are entrained in a stream of gas, and controls set the desired delivery weight rate for delivery of the solids to the delivery point. The weight of the container, which encloses the entraining system and the solids, is determined continuously.

Method and apparatus for effecting pneumatic conveyance of particulate solids

Powdered particles are continuously distributed from a pressurized transporting vessel to a plurality of receiving ends such as tuyers of a blast furnace through a plurality of transporting pipes for each receiving end A speed of gas supplied to the vessel is controlled depending on a weight changing ratio of the vessel and an internal pressure of the vessel, so that the speed of gas is maintained at constant Booster gas is supplied to each of the transporting pipes A discharging rate of the powdered particles is controlled by a cascade control system for each of the pipes by individually controlling a flow rate of booster gas depending on a differential pressure in each discharge nozzle of the pipes, or on an output of solid-gas mass-flow meter in each of the pipes, or on a solid-gas ratio corresponding to each length of the pipes and a mass-flow rate of the particles in the vessel per total gas flow rate

Method and apparatus for distributing powdered particles

The invention is directed to a method and apparatus for establishing and maintaining a uniform mass flow rate of particulate solids and gas mixture from a container to a receiving reactor. A preferred embodiment utilizes a plurality of porous inserts in the walls of the container through which a gaseous fluid is forced thereby contacting particulate solids within said container and enhancing the flow of said solids.

Aerated discharge device

A pulverized fuel delivery system for a blast furnace in which pulverized coal is delivered in dense phase fluidized form into the blast furnace from gas pressurized tanks that are placed in communication, one at a time, in cyclical sequence with a pneumatic transport means. The tank gas pressure is regulated in accordance with the blast furnace wind rate to control the weight flow rate of pulverized coal into the furnace and the transport gas flow rate is regulated in accordance with the fuel weight flow rate to maintain a prescribed transport gas flow rate per pound of coal delivered to the furnace.

Elias A. Kazmierski

Papers

Pulverized fuel delivery system for a blast furnace

Gas tube vapor generator