Water-containing solid fuel drying apparatus and drying method

Patent metadata

Field	Value
Publication number	US-9518736-B2
Application number	US-201013319865-A
Country	US
Kind code	B2
Filing date	May 25, 2010
Priority date	May 28, 2009
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

A water-containing solid fuel drying apparatus that can efficiently dry with low energy consumption by effectively utilizing sensible heat and latent heat of a heating medium for drying, etc. is provided. A drying apparatus ( 10 ) that dries water-containing solid fuel includes a dryer ( 20 ) that injects scavenging gas into the interior of a drying vessel ( 21 ) in which a heat transfer pipe ( 22 ) is disposed; a dust collector ( 13 ) that removes microparticles from microparticle-containing mixed gaseous fluid that has flowed out of the drying vessel ( 21 ); a compressor ( 30 ) that compresses vapor-containing mixed gaseous fluid; a vapor heat exchanger ( 31 ) that preheats low-pressure mixed gaseous fluid with high-pressure mixed gaseous fluid compressed at the compressor ( 30 ); and a gas-liquid separator ( 14 ), in which the high-pressure mixed gaseous fluid is employed as drying gas that radiates heat by passing through the heat transfer pipe ( 22 ), that performs gas-liquid separation of water-containing scavenging gas that has flowed out of the heat transfer pipe ( 22 ) while containing condensed water of vapor generated due to heat radiation, wherein the water-containing solid fuel is dried by heating the water-containing solid fuel in the drying vessel ( 21 ) utilizing latent heat and sensible heat of the mixed gaseous fluid.

First claim

The invention claimed is:

1. A water-containing solid fuel drying apparatus, comprising:
a dryer that dries water-containing solid fuel by heating the water-containing solid fuel with drying gas, the dryer including a drying vessel into which the water-containing solid fuel and scavenging gas is injected and a heat transfer pipe for flowing the drying gas, the heat transfer pipe being disposed in the drying vessel;
a dust collector, into which the scavenging gas that has flowed out of the drying vessel is introduced in a form of first mixed gaseous fluid that contains vapor evaporated from the water-containing solid fuel and microparticles of the water-containing solid fuel, for removing the microparticles from the first mixed gaseous fluid and generating second mixed gaseous fluid that contains the vapor and the scavenging gas;
a compressor that compresses the second mixed gaseous fluid introduced thereinto and generates the drying gas;
a turbine that is used as a driving source for operating the compressor;
a heat exchanger that preheats the second mixed gaseous fluid with the drying gas that has been compressed at the compressor and has higher pressure than pressure of the second mixed gaseous fluid and that supplies the second mixed gaseous fluid that has been preheated to the compressor, the heat exchanger introducing the second mixed gaseous fluid from the dust collector and introducing the drying gas from the compressor; and
a gas-liquid separating device that performs gas-liquid separation by introducing water-containing scavenging gas which flows out from the heat transfer pipe, the water-containing scavenging gas being gas that contains moisture formed through condensing of vapor contained in the drying gas, the gas-liquid separating device supplying the scavenging gas separated from the water-containing scavenging gas to the turbine, wherein
the scavenging gas generated by removing the moisture from the water-containing scavenging gas at the gas-liquid separating device circulates while undergoing repeated phase changes through the first mixed gaseous fluid, the second mixed gaseous fluid, the drying gas, and the water-containing scavenging gas, in this order, the water-containing scavenging gas is reused upon returning to the scavenging gas, and the water-containing solid fuel is dried by heating the water-containing solid fuel with latent heat of vapor contained in the drying gas and sensible heat of the drying gas.

2. A water-containing solid fuel drying apparatus according to claim 1 , wherein a fluidized bed is employed in the drying vessel and the scavenging gas serves as fluidizing gas.

3. A water-containing solid fuel drying apparatus according to claim 1 , further comprising
a primary-drying heat exchanger that is disposed between the drying vessel and the gas-liquid separating device and that preheats the water-containing solid fuel before being injected in the drying vessel with the water-containing scavenging gas that flows out of the heat transfer pipe.

4. A water-containing solid fuel drying apparatus according to claim 1 , further comprising
a pressure-release mechanism that reduces the pressure of the scavenging gas that has been separated at the gas-liquid separating device, before being injected into a vessel bottom portion of the drying vessel.

5. A water-containing solid fuel drying apparatus according to claim 4 , wherein the pressure-release mechanism is the turbine that is coaxially connected to the compressor as the driving source of the compressor and that is driven by the scavenging gas.

6. A water-containing solid fuel drying apparatus according to claim 4 , wherein the pressure-release mechanism is a pressure-release valve.

7. A water-containing solid fuel drying apparatus according to claim 1 , further comprising
a preheating heating portion that heats the scavenging gas separated at the gas-liquid separating device and that injects the scavenging gas into the drying vessel.

8. A water-containing solid fuel drying apparatus according to claim 1 , further comprising a start-up heating portion that heats the scavenging gas separated at the gas-liquid separating device and/or the water-containing solid fuel before being injected into the drying vessel.

9. A method of drying water-containing solid fuel, comprising:
forming a fluidized bed by injecting fluidizing gas from a bottom portion of a drying vessel in which a heat transfer pipe for flowing drying gas is disposed;
drying water-containing solid fuel injected into the drying vessel by heating the water-containing solid fuel with the drying gas;
generating second mixed gaseous fluid that contains vapor and the fluidizing gas by removing microparticles of the water-containing solid fuel from first mixed gaseous fluid that contains the vapor evaporated from the water-containing solid fuel and the microparticles of the water-containing solid fuel;
generating the drying gas by compressing the second mixed gaseous fluid at a compressor;
preheating the second mixed gaseous fluid with the drying gas that has been compressed at the compressor and has higher pressure than pressure of the second mixed gaseous fluid by introducing the second mixed gaseous fluid and the drying gas into a heat exchanger, the second mixed gaseous fluid that has been preheated being supplied to the compressor;
generating the fluidizing gas by removing moisture from water-containing fluidizing gas which flows out from the heat transfer pipe, the water-containing fluidizing gas being gas that contains the moisture formed through condensing of vapor contained in the drying gas;
supplying the fluidizing gas to a turbine that is used as a driving source for operating the Compressor;
forming a circulation system, in which the fluidizing gas repeatedly undergoes phase changes among initial fluidizing gas, the first mixed gaseous fluid, the second mixed gaseous fluid, the drying gas and the water-containing fluidizing gas, in this order, and the water-containing fluidizing gas is reused upon returning to the fluidizing gas; and
drying the water-containing solid fuel by heating the water-containing solid fuel with latent heat of vapor contained in the drying gas and sensible heat of the drying gas.

10. A water-containing solid fuel drying apparatus, comprising:
a dryer that dries water-containing solid fuel by heating the water-containing solid fuel with drying gas, the dryer including a drying vessel into which the water-containing solid fuel and scavenging gas is injected and a heat transfer pipe for flowing the drying gas, the heat transfer pipe being disposed in the drying vessel;
a dust collector, into which the scavenging gas that has flowed out of the drying vessel is introduced in a form of first mixed gaseous fluid that contains vapor evaporated from the water-containing solid fuel and microparticles of the water-containing solid fuel, for removing the microparticles from the first mixed gaseous fluid and generating second mixed gaseous fluid that contains the vapor and the scavenging gas;
a compressor that compresses the second mixed gaseous fluid introduced thereinto and generates the drying gas;
a turbine that is used as a driving source for operating the compressor;
a heat exchanger that preheats the second mixed gaseous fluid with the drying gas that has been compressed by the compressor and has higher pressure than pressure of the second mixed gaseous fluid and that supplies the second mixed gaseous fluid that has been preheated to the compressor, the heat exchanger introducing the second mixed gaseous fluid from the dust collector and introducing the drying gas from the compressor;
a gas-liquid separating device that performs gas-liq

Assignees

• Yokohama Katsuhiko
• Kosaka Kenichiro
• Matsumoto Keigo
• Kawamoto Noboru
• Yamaguchi Yoshiki
• Kinoshita Masaaki
• Ohura Koji
• Tsutsumi Atsushi
• Kaneko Shozo
• Mochizuki Kazuhiro
• Fushimi Chihiro
• Kansha Yasuki
• Mitsubishi Heavy Ind Ltd
• Univ Tokyo

Inventors

• Yokohama Katsuhiko
• Kosaka Kenichiro
• Matsumoto Keigo
• Kawamoto Noboru
• Yamaguchi Yoshiki
• Kinoshita Masaaki
• Ohura Koji
• Tsutsumi Atsushi
• Kaneko Shozo
• Mochizuki Kazuhiro
• Fushimi Chihiro
• Kansha Yasuki

Classifications

• F26B23/004

  by compressing and condensing vapour in exhaust gases, i.e. using an open cycle heat pump system · CPC title

• C10L9/08

  by heat treatments, e.g. calcining · CPC title

• F23K1/04 Primary

  Heating fuel prior to delivery to combustion apparatus · CPC title

• Y02P70/405

  Cross-Sectional Technologies · mapped topic

• F23K2201/20

  Drying · CPC title