Carbonaceous feedstock gasification power generation facility, and method for regulating drying gas carbonaceous feedstock

Patent metadata

Field	Value
Publication number	US-11084995-B2
Application number	US-201716097903-A
Country	US
Kind code	B2
Filing date	May 10, 2017
Priority date	May 20, 2016
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A carbonaceous feedstock gasification power generation facility, and a method for regulating a gas for drying gas this carbonaceous feedstock, are disclosed with which it is possible to expand the range of the types of carbonaceous feedstocks that can be used. High-temperature exhaust gas, low-temperature exhaust gas and extreme high-temperature exhaust gas are bled from the furnace respectively at a high-temperature bleed position, a low-temperature bleed position and an extreme high-temperature bleed position. When these exhaust gases are mixed, the flow volume of the extreme high-temperature exhaust gas supplied to at least one of the exhaust gases, that is, the high-temperature exhaust gas or the low-temperature exhaust gas, is adjusted such that the temperature of at least one of these exhaust gases, that is, the high-temperature exhaust gas or the low-temperature exhaust gas, reaches a prescribed temperature.

First claim

The invention claimed is:

1. A carbonaceous feedstock gasification power generation facility, comprising:
a pulverizing device that pulverizes a carbonaceous feedstock to produce a pulverized fuel;
a gasifier that gasifies the pulverized fuel to generate a raw syngas;
a gas turbine that is driven by a combustion gas obtained by combusting the raw syngas;
a generator that is connected to the gas turbine and driven by the gas turbine;
a heat recovery steam generator that introduces an exhaust gas being discharged from the gas turbine, is provided with an upstream-side heat exchange portion made up of one or more heat exchangers, an in-furnace denitration device which is a denitration device provided in the gasifier, and a downstream-side heat exchange portion made up of one or more heat exchangers in a furnace in this order from an exhaust gas upstream side, and generates a steam by recovering heat from the exhaust gas in the upstream-side heat exchange portion and the downstream-side heat exchange portion;
a high-temperature exhaust gas line that bleeds a high-temperature exhaust gas from the furnace at a high-temperature bleed position which is set on an exhaust gas downstream side of the in-furnace denitration device and supplies the high-temperature exhaust gas to the pulverizing device as a drying gas the carbonaceous feedstock, the high-temperature exhaust gas which is bled from a bleed position which is set on the downstream side of the upstream-side heat exchange portion and the in-furnace denitration device and the upstream side of the downstream-side heat exchange portion;
a low-temperature exhaust gas line that bleeds a low-temperature exhaust gas from the furnace at a low-temperature bleed position which is set on the exhaust gas downstream side of the high-temperature bleed position and set so as to sandwich at least a part of the downstream-side heat exchange portion between the high-temperature bleed position and the low-temperature bleed position and supplies the low-temperature exhaust gas to the high-temperature exhaust gas line or directly to the pulverizing device, the low-temperature exhaust gas is bled from a bleed position which is set on the downstream side of the downstream-side heat exchange portion;
an extreme high-temperature exhaust gas line that bleeds an extreme high-temperature exhaust gas from the furnace at an extreme high-temperature bleed position which is set on an exhaust gas upstream side of the high-temperature bleed position between an exhaust gas outlet of the gas turbine and the in-furnace denitration device which is a denitration device provided in the gasifier and set so as to sandwich at least a part of the upstream-side heat exchange portion between the high-temperature bleed position and the extreme high-temperature bleed position and supplies the extreme high-temperature exhaust gas to at least one exhaust gas line of the high-temperature exhaust gas line and the low-temperature exhaust gas line, the extreme high-temperature exhaust gas is bled from a bleed position which is set on the upstream side of the upstream-side heat exchange portion; and
temperature adjustment damper that is interposed in the extreme high-temperature exhaust gas line and adjusts a flow rate of the extreme high-temperature exhaust gas being supplied to the at least one exhaust gas line so that a gas temperature in the at least one exhaust gas line reaches a prescribed temperature.

2. The carbonaceous feedstock gasification power generation facility according to claim 1 , further comprising:
a drying gas discharging line that discharges the drying gas used to dry the carbonaceous feedstock from the pulverizing device;
a NO x sensor that detects a nitrogen oxide concentration of the drying gas in the drying gas discharging line; and
a flow rate adjustment valve that adjusts a supply amount of a reducing agent being supplied to the in-furnace denitration device according to a detection signal from the nitrogen oxide concentration detection means.

3. The carbonaceous feedstock gasification power generation facility according to claim 1 , further comprising:
a drying gas discharging line that discharges the drying gas used to dry the carbonaceous feedstock from the pulverizing device,
wherein the drying gas discharging line is connected to the furnace on the exhaust gas upstream side of the in-furnace denitration device.

4. The carbonaceous feedstock gasification power generation facility according to claim 3 , further comprising:
a temperature adjustment damper in the drying gas discharging line,
wherein, in a case in which a temperature of the drying gas detected using the temperature detection means is lower than a reference temperature set on the basis of a maximum efficiency temperature of the in-furnace denitration device, the maximum efficiency temperature is the temperature at which the denitration efficiency of the denitration device is maximized, an opening degree of at least one of a water supply valve that controls an amount of water being supplied to the heat recovery steam generator and a steam valve that controls an amount of a steam from the heat recovery steam generator is decreased.

5. The carbonaceous feedstock gasification power generation facility according to claim 1 , further comprising:
an external denitration device which is a denitration device provided outside the gasifier, in the extreme high-temperature exhaust gas line.

6. A method for adjusting a drying gas being used to dry a carbonaceous feedstock in a carbonaceous feedstock gasification power generation facility including a gasifier that gasifies a carbonaceous feedstock to generate a raw syngas, a gas turbine that is driven by a gas for combustion obtained by combusting the raw syngas, a generator that is connected to the gas turbine and driven by the gas turbine, and a heat recovery steam generator that generates a steam by recovering heat from an exhaust gas in being discharged from the gas turbine, in which the heat recovery steam generator is provided with an upstream-side heat exchange portion made up of one or more heat exchangers, an in-furnace denitration device which is a denitration device provided in the gasifier, and a downstream-side heat exchange portion made up of one or more heat exchangers in a furnace in this order from an upstream side in a circulation direction of the exhaust gas,
the method comprising:
bleeding a high-temperature exhaust gas from the furnace at a high-temperature bleed position which is set on a downstream side of the in-furnace denitration device in the circulation direction, the high-temperature exhaust gas which is bled from a bleed position which is set on the downstream side of the upstream-side heat exchange portion and the in-furnace denitration device and the upstream side of the downstream-side heat exchange portion;
bleeding a low-temperature exhaust gas from the furnace at a low-temperature bleed position which is set on the downstream side of the in-furnace denitration device and the high-temperature bleed position in the circulation direction and set so as to sandwich at least a part of the downstream-side heat exchange portion between the high-temperature bleed position and the low-temperature bleed position, the low-temperature exhaust gas is bled from a bleed position which is set on the downstream side of the downstream-side heat exchange portion;
bleeding an extreme high-temperature exhaust gas from the furnace at an extreme high-temperature bleed position which is set on an exhaust gas upstream side of the high-temperature bleed position between an outlet of the exhaust gas from the gas turbine and the in-furnace denitration device and set so as to sandwich at least a part of the upstream-side heat exchange portion between the hig

Assignees

• Mitsubishi Hitachi Power Sys Ltd
• Mitsubishi Power Ltd

Inventors

• Sakamoto Koichi
• Ishii Hiromi
• Fujii Takashi
• Yoshida Shogo

Classifications

• C10J2300/1678

  with air separation · CPC title

• C10J2300/0906

  Physical processes, e.g. shredding, comminuting, chopping, sorting · CPC title

• C10J2300/1687

  with steam generation · CPC title

• F23K1/04

  Heating fuel prior to delivery to combustion apparatus · CPC title

• C10J2300/0959

  Oxygen · CPC title