A integrated coal gasification combined cycle is the cycle aimed at higher efficiency and higher environmental performance compared with conventional coal-fired power generation by gasifying coal and combining it with combined cylinder power generation. The integrated coal gasification combined cycles has a great advantage that coal having a large amount of resources is also available. It is known that the advantage becomes greater by increasing applied kinds of coal.
Generally, the conventional integrated coal gasification combined cycles have a coal feed apparatus, a coal gasifier, a char recovery apparatus, gas purification equipment, gas turbine equipment, steam turbine equipment, and a heat recovery steam generator. Accordingly, coal (pulverized coal) is fed to the coal gasifier by the coal feed apparatus, a gasifying agent (air, oxygen-enriched air, oxygen, steam, or the like) is taken in, the coal is combusted and gasified in this coal gasifier, and product gas (syngas) is produced. Then, as this product gas is purified after the unburned coal (char) of the coal is removed in the char recovery apparatus, and is fed to the gas turbine equipment, the product gas is combusted to produce high-temperature high-pressure combustion gas to drive a turbine. The heat energy of the exhaust gas after driving the turbine is recovered by the heat recovery steam generator to produce steam, and the steam is fed to the steam turbine equipment to drive the turbine. Accordingly, power generation is performed. Meanwhile, the exhaust gas of which the heat energy is recovered is emitted to the atmospheric air via a chimney.
The char recovery apparatus in the above-described integrated coal gasification combined cycle removes contained char, using a plurality of stages of dust collectors, from the product gas produced by the coal gasifier. Then, the collected char is returned to the coal gasifier by a predetermined amount by the char feed device. That is, a bin system having a char conveyance device is applied herein. General bin systems have one bin (or a plurality of bins), a plurality of char discharge lines which discharge char collected by respective dust collectors to this bin, and a plurality of char feed lines which feed the char collected in the bin to a plurality of hoppers (or one hopper).
As a conventional bin system, for example, there is one described in the following PTL 1, and as a powder conveyance device, for example, there is one described in the following PTL 2.