EP-4741747-A2 - APPARATUS FOR REMOVING MOISTURE FROM PARTICULATE MATERIAL

EP4741747A2EP 4741747 A2EP4741747 A2EP 4741747A2EP-4741747-A2

Abstract

Moisture is removed from particulate material using an apparatus comprising a dryer having a drying chamber for directing a flow of gas-entrained particulate material between first and second ends of the drying chamber. The dryer is configured for directing gas under pressure into the drying chamber, for interacting with a flow of gas-entrained particulate material within the drying chamber. The dryer comprises a body of modular construction, which defines a plurality of guide passages arranged for fluid communication between the drying chamber and a source of gas under pressure. The body of modular construction comprises a plurality of discrete annular elements, arranged in series, one adjacent another, each having a body defining a central aperture, and wherein the annular elements are arranged together with the central apertures aligned.

Inventors

FOSS-SMITH, PATRICK
ANDERSON, PETER

Assignees

Coomtech Limited

Dates

Publication Date: 20260513
Application Date: 20171102

Claims (15)

Apparatus for removing moisture from particulate material, the apparatus comprising a dryer having a drying chamber for directing a flow of gas-entrained particulate material between first and second ends of the drying chamber; and wherein the dryer is configured for directing gas under pressure into the drying chamber, for interacting with a flow of gas-entrained particulate material within the drying chamber; wherein the dryer comprises: a body, which defines a plurality of guide passages arranged for fluid communication between the drying chamber and a source of gas under pressure; a first type of guide passage in fluid communication with said drying chamber, wherein said first type of guide passage is configured to direct a blade or shaft of gas into the drying chamber for the purpose of intersecting the flow of material travelling through the drying chamber, between said first and second ends of the drying chamber; and a second type of guide passage in fluid communication with said drying chamber, wherein said second type of guide passage is configured to direct gas into the drying chamber in a direction intended to travel about the longitudinal axis within the drying chamber, in order to create a spinning effect, between said first and second ends of the drying chamber.
Apparatus according to claim 1, wherein the dryer comprises a plurality of said first type of guide passage, in an array along a length of the drying chamber.
Apparatus according to claim 2, wherein the first type of guide passage has an outlet which is continuous through 360 degrees.
Apparatus according to any previous claim, wherein the dryer comprises a plurality of said second type of guide passage, in an array along a length of the drying chamber.
Apparatus according to any previous claim, wherein the dryer is configured such that one or more of said second type of guide passage is arranged in series downstream of at least one of said first type of guide passage.
Apparatus according to any previous claim, wherein the first type of gas guide or guide passage is of a type configured to direct gas under pressure in a radial direction with respect to a longitudinal axis of the drying chamber, or in a radial direction with respect to a general direction of flow of gas-entrained particulate material.
Apparatus according to any previous claim, wherein the second type of gas guide or guide passage is of a type configured to direct gas under pressure in a tangential direction with respect to a longitudinal axis of the drying chamber, or in a tangential direction with respect to a general direction of flow of gas-entrained particulate material.
Apparatus according to any previous claim, wherein said first type of gas guide or guide passage and/or said second type of gas guide or guide passage is configured for directing a flow of gas into the drying chamber in a plane perpendicular to the direction of flow of material within the drying chamber, or at an angle to the perpendicular.
A method of removing moisture from particulate material, comprising the steps of: providing a drying chamber having first and second ends; directing a flow of gas-entrained particulate material between said first and second ends of the drying chamber; directing gas under pressure into the drying chamber, in order to interact with the flow of gas-entrained particulate material within the drying chamber; wherein the drying chamber defines a longitudinal axis; wherein a first type of gas guide or guide passage is of a type configured to direct a blade or shaft of gas into the drying chamber for the purpose of intersecting the flow of material travelling through the drying chamber (e.g. in a radial or axial direction with respect to said longitudinal axis); and wherein a second type of gas guide or guide passage is of a type configured to direct gas into the drying chamber in a direction intended to travel about the longitudinal axis within the drying chamber, in order to create a spinning effect, wherein the first type of gas guide is different to the second type of gas guide.
The method according to claim 9, wherein the second type of gas guide or guide passage is used downstream of the first type of gas guide or guide passage
Apparatus for removing moisture from particulate material, the apparatus comprising: a dryer having a drying chamber with a first end and a second end, wherein the apparatus is configured to create a helical flow of particulate material passing along the drying chamber between said first end and said second end in a first rotational sense; and wherein the drying chamber includes one or more gas guides or guide passages for directing gas under pressure into the drying chamber, for interacting with a flow of gas-entrained particulate material within the drying chamber, wherein said one or more gas guides or guide passages are configured to direct gas in a generally tangential or rotational manner, in a second rotational sense which is counter to said first rotational sense, in order to create a reverse spin effect within the flow of gas-entrained particulate material.
Apparatus according to claim 11, wherein the one or more gas guides or guide passages are configured for directing the gas flow into the drying chamber in a plane perpendicular to the direction of flow of material within the drying chamber, or in a direction at an angle to the perpendicular.
A method of removing moisture from particulate material, comprising the steps of: providing a drying chamber having first and second ends; directing a flow of gas-entrained particulate material between said first and second ends of the drying chamber; directing gas under pressure into the drying chamber, in order to interact with the flow of gas-entrained particulate material within the drying chamber; wherein the flow of gas-entrained particulate material is directed to follow a helical flow path in a first rotational sense from said first end of the drying chamber to the second end of the drying chamber; and wherein gas under pressure is directed into the drying chamber at a first location between said first and second ends of the drying chamber, in a rotational or tangential manner with respect to the direction of travel of the particulate material between said first and second ends, but in a second rotational sense which is counter to said first rotational sense, in order to shock the flow of particulate material moving between the first and second ends of the drying chamber.
A method according to claim 13, wherein gas under pressure is directed into the drying chamber at a second location between said first and second ends of the drying chamber, wherein said second location is downstream from said first location, and wherein said gas at said second location is directed in a rotational or tangential manner with respect to the direction of travel of the particulate material between said first and second ends, but in said first rotational sense, in order to re-promote the direction of helical flow of particulate material moving between the first and second ends of the drying chamber.
A method according to claim 13 or 14, wherein the first rotational sense is clockwise, and the second rotational sense is anti-clockwise.

Description

FIELD OF THE INVENTION The present invention relates to apparatus for removing moisture from particulate material, such as coal or biomass. BACKGROUND OF THE INVENTION Wet coal causes significant inefficiency in coal-fired power generation boilers and supercritical water heaters. More coal has to be burned to reach the target electrical output than would be needed if the coal was dry. In addition, atmospheric emissions could be significantly reduced if the moisture content of coal could be significantly reduced. Wet coal, and other particulate material, is traditionally dried using thermal processes to remove moisture, in particular surface moisture. However, this is very energy intensive, and so non-thermal methods are of huge value to industry. One such method is disclosed in previous patent application GB2494370, which describes an apparatus for removing moisture, in particular surface moisture, from coal or other solid particulate materials. The apparatus described uses cold air to dry organic and inorganic feedstocks. Trials of this system have indicated, however, that maintaining a high level of drying performance and efficiency, with high levels of throughput, is very difficult to achieve under all conditions. It has been found that different materials often have different requirements to ensure that effective and efficient drying is achieved. SUMMARY OF THE INVENTION According to a broadest aspect of the invention, there is provided an apparatus for removing moisture from particulate material, the apparatus comprising a dryer having a drying chamber for directing a flow of gas-entrained particulate material between first and second ends of the drying chamber. The dryer is configured for directing gas under pressure into the drying chamber, for interacting with a flow of gas-entrained particulate material within the drying chamber. The dryer may comprise a body of modular construction, which defines a plurality of guide passages arranged for fluid communication between the drying chamber and a source of gas under pressure. Using a modular construction allows the configuration of the dryer body to be readily adjusted, e.g. to optimise the drying efficiency of the dryer for any given type of particulate material to be processed (or level of surface moisture content to be processed for a given type of particulate material). For example, it may be possible to lengthen or shorten the dryer body, in order to increase or decrease the amount of time that material is present within the drying chamber. In exemplary embodiments, the configuration of the guide passages is adjustable. For example, the size of the guide passage may be adjusted, such as by increasing or decreasing the width of the guide passage. Such adjustability can be used to influence the performance parameters of the gas which flows into the drying chamber via the guide passages. As such, the configuration of the dryer body can be adjusted, to optimise the drying efficiency of the dryer for any given type of particulate material to be processed (or level of surface moisture content to be processed for a given type of particulate material). The body of modular construction may comprise a plurality of discrete elements arranged in series, one adjacent another. Accordingly, one or more elements may be replaced and or the array of elements may be reorganised, in order to suit a desired configuration of dryer required for processing a given type (or level of surface moisture content) of particulate material. In exemplary embodiments, the discrete elements are configured to cooperate in pairs, one element adjacent another. In exemplary embodiments, a surface from each discrete element in the pair defines at least part of a wall of the drying chamber (i.e. at a location between the first and second ends of the drying chamber). In exemplary embodiments, one or more pairs of said plurality of elements, or each pair of said plurality of elements, defines at least one guide passage extending between first and second elements of said pair, and configured for directing gas under pressure from between said pair and into the drying chamber. In exemplary embodiments, the drying chamber is arranged radially outboard of the body of modular construction. For example, the dryer may comprise a housing with said body of modular construction located within the housing, and with the drying chamber defining an annulus around the body of modular construction, e.g. between a radially outer surface of the body of modular construction and an internal surface of the housing. In such embodiments, the guide passages will be arranged for directing a flow of gas under pressure in a radially outward direction, into said drying chamber. In exemplary embodiments, the dryer comprises a first type of guide passage in fluid communication with said drying chamber, wherein said first type of guide passage is configured for directing gas under pressure in a radial direction with respec