Apparatus and method of enhancing the quality of high-moisture materials and separating and concentrating organic and/or non-organic material contained therein
The present invention harvests and utilizes fluidized bed drying technology and waste heat streams augmented by other available heat sources to dry feedstock or fuel. This method is useful in many industries, including coal-fired power plants. Coal is dried using the present invention before it goes to coal pulverizers and on to the furnace/boiler arrangement to improve boiler efficiency and reduce emissions. This is all completed in a low-temperature, open-air system. Also included is an apparatus for segregating particulate by density and/or size including a fluidizing bed having a particulate receiving inlet for receiving particulate to be fluidized. This is useful for segregating contaminants like sulfur and mercury from the product stream.
1. An open air apparatus for segregating particulate material by density and/or size to concentrate a contaminant for separation from the particulate material feed stream, comprising:
(a) a fluidizing bed having a receiving inlet for receiving the particulate material feed, an inlet opening for receiving a fluidizing stream, a first discharge outlet for discharging a fluidized particulate material product stream, and a second discharge outlet for discharging a non-fluidized particulate material stream;
(b) a source of fluidizing stream at a temperature of about 300° F. or less operatively connected to the inlet opening for introducing the fluidizing stream into the fluidizing bed to achieve separation of the fluidized particulate material product stream from the non-fluidized particulate material stream;
(c) a conveyor means located within the fluidized bed for transporting the non-fluidized particulate material from inside the fluidized bed to the outside of the fluidized bed through the second discharge outlet; and
(d) wherein the fluidized particulate material product stream contains a reduction in the contaminant relative to the particulate material feed stream, and the non-fluidized particulate material stream contains an increase in the contaminant relative to the particulate material feed stream.
2. The particulate material segregating apparatus of claim 1 , wherein the particulate material is coal.
3. The particulate material segregating apparatus of claim 2 , wherein the coal material is lignite coal.
4. The particulate material segregating apparatus of claim 2 , wherein the coal material is subbituminous coal.
5. The particulate material segregating apparatus of claim 2 , wherein the contaminant is selected from the group consisting of fly ash, sulfur, mercury, and ash.
6. The particulate material segregating apparatus of claim 5 , wherein the non-fluidized coal particulate material stream contains about 21-46% of the mercury originally contained in the coal particulate material feed stream, which is removed from the fluidized coal particulate product stream.
7. The particulate material segregating apparatus of claim 5 , wherein the non-fluidized coal particulate material stream contains about 19-36% of the sulfur originally contained in the coal particulate material feed stream, which is removed from the fluidized coal particulate product stream.
8. The particulate material segregating apparatus of claim 5 , wherein the non-fluidized coal particulate material stream contains about 23-43% of the fly ash originally contained in the coal particulate material feed stream, which is removed from the fluidized coal particulate product stream.
9. The particulate material segregating apparatus of claim 2 , wherein the coal of the fluidized particulate material product stream, when combusted, produces a flue gas having a reduction in SO x of about 4%.
10. The particulate material segregating apparatus of claim 2 , wherein the coal of the fluidized particulate material product stream, when combusted, produces a flue gas having a reduction in NO x of about 10%.
11. The particulate material segregating apparatus of claim 1 , wherein the fluidizing stream is air.
12. The particulate material segregating apparatus of claim 1 , wherein the fluidizing stream is steam.
13. The particulate material segregating apparatus of claim 1 , wherein the fluidizing stream is an inert gas.
14. The particulate material segregating apparatus of claim 1 , wherein the fluidizing stream is heated by a heat source prior to its introduction to the fluidizing bed.
15. The particulate material segregating apparatus of claim 14 , wherein the heat source is a principal heat source.
16. The particulate material segregating apparatus of claim 14 , wherein the heat source is a waste heat source.
17. The particulate material segregating apparatus of claim 16 , wherein the waste heat source is selected from the group consisting of hot condenser cooling water, hot stack gas, hot flue gas, spent process steam, and discarded heat from operating equipment.
18. The particulate material segregating apparatus of claim 1 further comprising a collection chamber operatively connected to the non-fluidized particulate material stream second discharge outlet for receiving the non-fluidized particulate material stream, the collection chamber including a second fluidizing bed and means for directing a second fluidizing stream through the non-fluidized particulate material contained within the collection chamber for separating fluidizable particles therefrom to further concentrate the contaminant within the non-fluidized particulate material stream.
19. The particulate material segregating apparatus of claim 18 , wherein the fluidizable particles separated from the non-fluidized particulate material stream in the collection chamber are returned to the fluidizing bed by a second fluidizing stream.