Process for recovering heat from stack or flue gas

Patent · Tue Jul 20 00:00:00 EDT 1982

OSTI ID:6669710

Ben-shmuel, D; Zacuto, P

A method and apparatus are disclosed for efficiently recovering heat from a gas stream such as discharged flue gas. The gas stream is countercurrently contacted with a liquid medium in two stages. A first countercurrent contact stage is between a partially cooled gas stream and cold liquid medium in a bed of packing through which the cold liquid medium flows downwards and the partially cooled gas stream flows upwards, so that a warmed liquid medium and fully cooled gas stream are produced. The second countercurrent contact stage is between the warmed liquid medium derived from the first contact stage and the hot initial gas stream in a plurality of parallel vertically oriented passages. The warmed liquid medium flows downward on the inner walls of the vertically oriented passages as a thin liquid film, while the hot initial gas stream flows upwards within the vertically oriented passages, so that a fully heated liquid medium and the partially cooled gas stream are produced. The second contact stage accomplishes high direct contact heat transfer with low mass transfer, so that minimal heat is lost as heat of vaporization of liquid medium evaporated into the gas stream. The fully heated liquid medium is passed in indirect heat exchange with a fluid, so that the liquid medium is cooled and the fluid, which may be water, air, or a process fluid stream, is heated.

• Assignee: EDB-83-017000
• Patent Number(s): US 4340572
• OSTI ID: 6669710
• Resource Relation: Patent File Date: Filed date 19 May 1978; Other Information: PAT-APPL-907667
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
01 COAL, LIGNITE, AND PEAT
02 PETROLEUM
FLUE GAS
HEAT RECOVERY
AQUEOUS SOLUTIONS
CORROSION PROTECTION
COUNTERFLOW SYSTEMS
HEAT TRANSFER
PARTICULATES
SULFUR DIOXIDE
SULFURIC ACID
WASTE HEAT UTILIZATION
CHALCOGENIDES
DISPERSIONS
ENERGY RECOVERY
ENERGY TRANSFER
GASEOUS WASTES
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MIXTURES
OXIDES
OXYGEN COMPOUNDS
PARTICLES
RECOVERY
SOLUTIONS
SULFUR COMPOUNDS
SULFUR OXIDES
WASTE PRODUCT UTILIZATION
WASTES
320305* - Energy Conservation
Consumption
& Utilization- Industrial & Agricultural Processes- Industrial Waste Management
010800 - Coal
Lignite
& Peat- Waste Management
020800 - Petroleum- Waste Management