초록 ▼

A cascading bed retorting process and apparatus in which cold raw crushed shale enters at the middle of a retort column into a mixer stage where it is rapidly mixed with hot recycled shale and thereby heated to pyrolysis temperature. The heated mixture then passes through a pyrolyzer stage where it

A cascading bed retorting process and apparatus in which cold raw crushed shale enters at the middle of a retort column into a mixer stage where it is rapidly mixed with hot recycled shale and thereby heated to pyrolysis temperature. The heated mixture then passes through a pyrolyzer stage where it resides for a sufficient time for complete pyrolysis to occur. The spent shale from the pyrolyzer is recirculated through a burner stage where the residual char is burned to heat the shale which then enters the mixer stage.

대표청구항 ▼

A method for retorting oil shale, wherein the oil shale particles are not uniform in size, and can include fines, comprising: burning residual char in particles of spent shale to heat the shale to a temperature greater than the pyrolysis temperature of raw shale; producing a continuous cascading gra

A method for retorting oil shale, wherein the oil shale particles are not uniform in size, and can include fines, comprising: burning residual char in particles of spent shale to heat the shale to a temperature greater than the pyrolysis temperature of raw shale; producing a continuous cascading gravity-flow of a non-fluidized layer of particles of cold raw shale and hot burned shale; segregating the particles by size in the flowing layer with smaller particles moving to the bottom of the layer and larger particles to the top; inverting the layer of particles so that the smaller particles are on the top of the layer and larger particles on the bottom; wherein the steps of producing a flowing layer, segregating the particles in the layer and inverting the layer are produced by flowing the particles down a series of downwardly sloped alternately opposed stationary baffles comprising a first segment having a slope, measured from the horizontal, in the range of about 24°-60°and a second segment joined to and above the first segment, the slope of the second segment being greater than the slope of the first segment, the series of baffles being arranged so that the lower tip of one baffle extends laterally to and above about the junction between the first and second segments of the next baffle; repeating the steps of segregating the particles in the layer and inverting the layer a sufficient number of times in a period of time of less than about 30 seconds to produce intimate mixing of the particles in the layer which allows later heat transfer to raise the temperature of the raw shale to the pyrolysis temperature; and producing a continuously moving packed-bed of the heated shale mixture after mixing has occurred, for a sufficient time to produce substantially total heat sharing in the mixture to raise the temperature of the raw shale to the pyrolysis temperature and to allow complete pyrolysis to occur.