| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the corrosion or clogging of a heat transfer tube of an exhaust gas heat recovering instrument without increasing the dust exhaust amount from a stack. SOLUTION: A system comprises a dust collector 3 for removing dust in boiler exhaust gas, an exhaust gas heat recovering instrument 4 with a heat transfer tube 8 for recovering a part of exhaust gas heat exhausted from the dust collector, a wet exhaust gas desulfurization equipment 5 for desulfurizing exhaust gas exhausted from the exhaust heat recovering instrument, an exhaust gas reheater 6 with a heat transfer tube 9 for heating exhaust gas exhausted from the exhaust gas desulfurization equipment and heating medium circulating pipes 10 and 11 for circulating the heating medium between the heat transfer tube 8 and the heat transfer tube 9. In that case, a heating medium heater 12 for keeping at least either one of the tube wall temperature of the heat transfer tube 8 of the exhaust gas heat recovering instrument 4 or the internal heating medium temperature at 80 deg.C or over is provided.</p> |
