BOILER SCALE REMOVING METHOD FOR BOILER FACILITY AND WASHING DEVICE

PROBLEM TO BE SOLVED: To perform an efficient removal of sulfur oxide scale and non-water soluble scale such as rust adhered to an outer surface of a heat transmission pipe of a waste heat recovery boiler, a water wall pipe to which boiler combustion gas is contacted, a superheater tube, a coal saving pipe, an air heater and an electric dust collector and the like.SOLUTION: A boiler plant is washed with water to remove scale of sulfur oxide. A circulation washing is carried out under application of the washing water used for removing scale of sulfur oxide to peel off and remove non-water soluble scale such as rust with circulating washing water of pH acid. Not only sulfur oxide scale adhered to the boiler plant but also non-water soluble scale such as rust can be efficiently removed only through circulation of the washing water without using any chemical solution, without requiring any complex cleaning device and without being restricted by a cleaning location.SELECTED DRAWING: Figure 1 【課題】排熱回収ボイラの伝熱管外面、ボイラ燃焼ガスが接触する水壁管、過熱器管、節炭器管、エアヒーター、電気集塵機等に付着した硫黄酸化物スケールと、錆などの非水溶性のスケールとを効率的に除去する。【解決手段】ボイラ設備を水洗して硫黄酸化物スケールを除去する。この硫黄酸化物スケールの除去に用いた水洗水を用いて循環洗浄を行うことにより、ｐＨ酸性の循環水洗水により、錆等の非水溶性のスケールを剥離除去する。ボイラ設備に付着した硫黄酸化物スケールのみならず、錆等の非水溶性のスケールをも、薬液を用いることなく、複雑な洗浄装置を必要とすることなく、また、洗浄部位に制約を受けることなく、水洗水を循環させるだけで、効率的に除去することができる。【選択図】図１