Abstract: An object of the invention is to realize high-accuracy analysis of a flue gas in terms of a trace amount of ammonia so as to control the level of ammonia gas to be added to a flue gas NOx removal apparatus. Since the ammonia gas to be determined is a highly absorbable, the gas component is considerably adsorbed on a surface of the flue gas sampling tube during sampling of flue gas. When a conventional sampling method including heating a gas sampling tube is employed, the amount of sampled gas is reduced through adsorption during gas sampling, failing to obtain concentration values at high accuracy. Thus, a high-accuracy gas sampling method replacing a conventional, heating-based method includes completely washing out, with an absorption liquid therefor serving as a washing liquid, a target ammonia gas deposited on the inner wall of a flue gas sampling tube (2), whereby the gas component is thoroughly collected. Through analysis of the thus-obtained washing liquid, high-accuracy analysis can be attained.

Abstract: An object of the invention is to realize high-accuracy analysis of a flue gas in terms of a trace amount of ammonia so as to control the level of ammonia gas to be added to a flue gas NOx removal apparatus. Since the ammonia gas to be determined is a highly adsorbable, the gas component is considerably adsorbed on a surface of the flue gas sampling tube during sampling of flue gas. When a conventional sampling method including heating a gas sampling tube is employed, the amount of sampled gas is reduced through adsorption during gas sampling, failing to obtain concentration values at high accuracy. Thus, a high-accuracy gas sampling method replacing a conventional, heating-based method includes completely washing out, with an absorption liquid therefor serving as a washing liquid, a target ammonia gas deposited on the inner wall of a flue gas sampling tube (2), whereby the gas component is thoroughly collected. Through analysis of the thus-obtained washing liquid, high-accuracy analysis can be attained.

Abstract: An apparatus for automatically measuring dust concentration in flue gas includes (a) a sampling unit for sampling dust in flue gas; (b) a measuring unit for measuring a gas flow of the flue gas; and (c) a feeding and weighing unit for feeding and weighing a filter paper for filtering the sampled gas, the feeding and weighing unit including (i) a filter paper cassette for storing the filter paper, (ii) a filter paper stocker for storing a plurality of the filter paper cassettes, (iii) a cassette pusher unit for pushing a filter paper cassette out of the filter paper stocker, (iv) a filter paper ascending unit for raising the filter paper, (v) a filter paper drier for drying the filter paper, (vi) a filter paper transfer arm for transferring the filter paper between the filter paper cassette, the filter paper ascending unit and the filter paper drier, (vii) a vibration-free balance for balancing the filter paper, and (viii) a hot air generation unit.