Boiler system and power plant including the same

A boiler system comprising:

• a boiler that burns fuel containing at least sulfur content, chlorine content, and water content, a weight percent concentration of the sulfur content being lower than 8.0%, a weight percent concentration of the chlorine content being lower than 0.1%, and a weight percent concentration of the water content being lower than 20.0%, to generate a combustion gas;
• a removal section that is arranged on a downstream side of the boiler and that removes sulfur oxide and nitrogen oxide contained in the combustion gas;
• a desulfurizing absorbent supply section that mixes a desulfurizing absorbent for removing sulfur oxide contained in the combustion gas into the combustion gas on an upstream side of the removal section;
• and
• a denitrating reagent supply section that mixes a denitrating reagent for removing nitrogen oxide contained in the combustion gas into the combustion gas on the upstream side of the removal section,
• wherein the removal section has a dry desulfurization function, and a temperature of the combustion gas flowing into the removal section is higher than 200° C. and 350° C. or lower.

An operation method for operating a boiler system including a boiler that burns fuel containing sulfur content at a weight percent concentration of lower than 8.0%, chlorine content at a weight percent concentration of lower than 0.1%, and water content at a weight percent concentration of lower than 20.0% to generate a combustion gas, the method comprising:

• a desulfurizing absorbent supply step that mixes a desulfurizing absorbent for removing sulfur oxide contained in the combustion gas into the combustion gas;
• a removal step that removes the sulfur oxide contained in the combustion gas and removes smoke dust contained in the combustion gas by using a removal section that removes the sulfur oxide contained in the combustion gas and removes the smoke dust contained in the combustion gas;
• a denitrating reagent supply step that mixes a denitrating reagent for removing nitrogen oxide contained in the combustion gas into the combustion gas;
• and
• a denitration step that removes the nitrogen oxide contained in the combustion gas from which the sulfur oxide has been removed by the removal step,
• wherein the removal step performs dry desulfurization, and a temperature of the combustion gas in the removal step is higher than 200° C. and 350° C. or lower, and
• the combustion gas from which the sulfur oxide has been removed by the removal step flows into the denitration step without being heated.

An operation method for operating a boiler system including a boiler that burns fuel containing at least sulfur content, chlorine content, and water content, a weight percent concentration of the sulfur content being lower than 8.0%, a weight percent concentration of the chlorine content being lower than 0.1%, and a weight percent concentration of the water content being lower than 20.0%, to generate a combustion gas, the method comprising:

• a desulfurizing absorbent supply step that mixes a desulfurizing absorbent for removing sulfur oxide contained in the combustion gas into the combustion gas;
• a denitrating reagent supply step that mixes a denitrating reagent for removing nitrogen oxide contained in the combustion gas into the combustion gas;
• and
• a removal step that removes the sulfur oxide and the nitrogen oxide contained in the combustion gas by using a removal section that removes the sulfur oxide and the nitrogen oxide contained in the combustion gas,
• wherein the removal step performs a dry desulfurization, and a temperature of the combustion gas in the removal step is higher than 200° C. and 350° C. or lower.