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AssigneeConsolidated Natural Gas Service Company, Inc.
InventorsLester G. Massey, Lawrence G. Clawson, Andrew J. Syska
Estimating the term…
Gas-solids transport and heat exchange techniques are disclosed wherein solid particulate material is circulated in a "figure 8" or a circular flow path for selective contact and/or direct heat exchange with gaseous media. The particulate material is introduced into streams of gaseous media at spaced locations in the flow path and subsequently separated from the gaseous streams following contact and/or heat exchange therewith. The gaseous streams are maintained separate from one another by loose packed bed columns of particulate material formed in the flow path and used to introduce the particulate material into the gaseous streams. The flow rate of the particulate material is regulated by the controlled biasing of particulate material from each of the columns thereof directly into the gaseous streams, and the particulate material is circulated solely through the use of the gaseous media and the force of gravity. The particulate material is circulated in cocurrent relationship with each of the gaseous streams in figure 8 flow path systems and, in circular flow path systems, the particulate material is circulated in cocurrent relationship with one of the gaseous streams and in countercurrent relationship with the other of the gaseous streams. In heat exchange applications, heat transfer between the streams of gaseous media is provided as a function of the flow rate of the particulate material and the relative flow rates of the streams of gaseous media.
A method of heat exchange between gaseous media and a particulate material which provides a heat exchange surface as it is circulated between first and second vessels for direct heat transfer with gaseous media comprising respectively withdrawing said particulate material from said vessels through first and second downcomers and transferring said particulate material to associated lift lines, pneumatically conveying said particulate material to said first vessel with a first gaseous stream flowing through one of said lift lines and to said second vessel with a second gaseous stream flowing through the other of said lift lines, each of said streams undergoing a pressure drop during the pneumatic conveyance of said particulate material, cocurrently transferring heat between said particulate material and gaseous stream in each of said lift lines, separating said particulate material from each of said gaseous streams and respectively collecting said particulate material in said vessels, and transferring heat between said gaseous streams as a function of the flow rate weight ratios of said particulate material to said gaseous stream in each of said lift lines and the flow rate weight ratio of said gaseous streams.
A method of cocurrent heat exchange for direct heat transfer between gaseous media and particulate material which provides a heat exchange surface as it is circulated between first and second operating vessels comprising withdrawing particulate material from said vessels through first and second downcomers, forming a loose packed bed column of particulate material under the influence of gravity in each of said downcomers, forming an accumulation of particulate material adjacent the bottom of each of said columns to restrict the withdrawal of particulate material through said downcomers, biasing particulate material from said accumulation thereof adjacent the bottom of each of said columns into an associated lift line, pneumatically conveying said particulate material to said first vessel with a first gaseous stream flowing through one of said lift lines and to said second vessel with a second gaseous stream flowing through the other of said lift lines, cocurrently transferring heat between said particulate material and said gaseous stream in each of said lift lines and substantially completing the transfer of heat between said gaseous streams and particulate material during pneumatic conveyance, and separating said particulate material from each of said gaseous streams.
A method of heat exchange between gaseous media and particulate material which provides a heat exchange surface as it is circulated between first and second operating vessels for direct heat exchange with gaseous media in a system characterized by heat exchange operating variables including gaseous media outlet temperatures and pressure drops comprising respectively withdrawing particulate material from said vessels through first and second downcomers and transferring the particulate material to associated lift lines, pneumatically conveying the particulate material to said first vessel with a first gaseous stream flowing through one of said lift lines and to said second vessel with a second gaseous stream flowing through the other of said lift lines, cocurrently transferring heat between said particulate material and said gaseous stream in each of said lift lines, separating said particulate material from each of said gaseous streams, sensing a heat exchange operating variable of said system, and varying the area of said heat exchange surface as a function of said sensed variable by controlling the rate of withdrawal of particulate material through at least one of said downcomers to recover at least one of said gaseous streams at a preselected value of said sensed operating variable.
A method of recovering heat from process gases comprising circulating a particulate material between first and second operating vessels in a figure 8 flow pattern, respectively withdrawing particulate material from said vessels through first and second downcomers and transferring the withdrawn particulate material to associated lift lines for pneumatic conveyance, forming a stream of a primary fluid comprising a process gas from which heat is to be recovered in one of said lift lines and a stream of a secondary fluid comprising a gaseous medium to which the recovered heat is to be transferred in the other of said lift lines, pneumatically conveying said particulate material through the respective lift lines to said vessels by means of said fluid streams, cocurrently transferring heat directly between said particulate material and fluid streams during pneumatic conveyance, separating said particulate material from said fluid streams to respectively collect said particulate material in said operating vessels, recovering said secondary fluid at a preselected elevated outlet temperature and/or pressure, and controlling the flow of said particulate material through at least one of said downcomers as a function of said preselected outlet temperature and/or pressure of the recovered secondary fluid.
A method of heat exchange between separate streams of gaseous media using particulate material which is circulated along a continuous flow path for separate contact at spaced locations along the flow path with first and second gaseous streams comprising, introducing said particulate material into said first gaseous stream at a first location in said flow path for direct contact and heat transfer with the first gaseous stream as the particulate material is circulated along the flow path to a second location therein, separating said particulate material from said first gaseous stream at said second location and introducing said particulate material into said second gaseous stream for direct contact and heat transfer with said second gaseous stream as the particulate material is circulated along the flow path to said first location, separating said particulate material from said second gaseous stream at said first location and introducing the particulate material into said first gaseous stream, monitoring the pressure drop of at least one of said gaseous streams and introducing said particulate material into said at least one gaseous stream as a function of said pressure drop, and cocurrently exchanging heat between said particulate material and each of said gaseous streams during contact therewith.
A method of heat transfer between separate streams of flowing gaseous media using a particulate material which is circulated between first and second operating chambers for respectively contacting first and second gaseous streams therein, comprising:
A heat exchanger apparatus for providing heat transfer between separate streams of gaseous media comprising first and second vessels having a particulate material circulated therebetween in a figure 8 flow pattern, first and second lift lines for respectively confining said streams as each of said streams pneumatically conveys said particulate material with cocurrent heat transfer to an associated one of said vessels, downcomers respectively associated with each of said vessels, each of said downcomers having an upper inlet for withdrawing particulate material from said vessel and a lower outlet for transferring particulate material to an associated one of said lift lines for pneumatic conveyance of said particulate material from one of said vessels to the other of said vessels, each of sad downcomers having a substantially unobstructed cross sectional area including a substantially vertical portion between said upper inlet and lower outlet for confining said particulate material in a loose packed bed column and a laterally extending portion for accumulating and transferring said particulate material to said associated lift line, and separation means associated with each of said vessels for separating said streams and particulate material and collecting said particulate material in said vessels for withdrawal by said downcomers.
A method of heat exchange between separate streams of gaseous media using particulate material which is circulated along a continuous flow path for separate contact at spaced locations along the flow path with first and second gaseous streams comprising, introducing said particulate material into said first gaseous stream at a first location in said flow path for direct contact and heat transfer with the first gaseous stream as the particulate material is circulated along the flow path to a second location therein, separating said particulate material from said first gaseous stream at said second location and providing in said flow path a loose packed bed column of said particulate which terminates at a lower accumulation of particulate material in its natural angle of repose, introducing said particulate material into said second gaseous stream by biasing said particulate material from the accumulation thereof directly into said stream for cocurrent heat transfer with said second gaseous stream as the particulate material is pneumatically conveyed along the flow path to said first location by said second gaseous stream, and separating said particulate material from said second gaseous stream at said first location and introducing the particulate material into said first gaseous stream, the step of biasing said particulate material from said accumulation including monitoring the pressure drop of said second gaseous stream during pneumatic conveyance and biasing said particulate material into said stream as a function of the pressure drop to control the flow of particulate material along the flow path.
A method of heat exchange between separate streams of gaseous media in a system having heat exchange operating variables including gaseous media outlet temperatures and pressure drops, comprising circulating particulate material which provides a heat exchange surface along a continuous flow path for separate contact at spaced locations along the flow path with first and second gaseous streams, introducing said particulate material into said first gaseous stream at a first location in said flow path for direct contact and heat transfer with the first gaseous stream as the particulate material is circulated along the flow path to a second location therein, separating said particulate material from said first gaseous stream at said second location and introducing said particulate material into said second gaseous stream for direct contact and heat transfer with said second gaseous stream as the particulate material is circulated along the flow path to said first location, separating said particulate material from said second gaseous stream at said first location for introduction of the particulate material into said first gaseous stream, cocurrently exchanging heat between said particulate material and at least one of said gaseous streams during contact therewith, sensing at least one of said heat exchange operating variables, and varying the area of said heat exchange surface in accordance with the sensed variable's deviation from a preselected value by regulating the introduction of said particulate material into said gaseous streams at said first and second locations.
A method of heat transfer between separate streams of flowing gaseous media in a system having heat exchange operating variables including gaseous media outlet temperatures and pressure drops, wherein a particulate material provides a heat exchange surface as it is circulated between first and second operating chambers for respectively contacting first and second gaseous streams therein, comprising:
Dependencies are inferred from the claim text.