| 摘要 |
PURPOSE:To make a corrosion-resistant surface-treatment and a neutralizer for condensed water unnecessary for the heat exchanger part and the exhaust part of a burner, by using a burner of which generation rate of NOx is below the specified value as a combustion burner, and by decreasing the acid concentration in condensed water produced during combustion in combustion gas. CONSTITUTION:Fuel is burnt in a combustion chamber 2 by two stage firing burner of which generation rate of NOx is below 2ppm, and combustion gas is heat-exchanged for water by a primary heat exchanger 3, through which a hot water feed pipe 10 is penetrated. Then, the combustion gas, passing through the bent part 4 of a heat exchanger, is fed into a secondary heat exchanger 5 to give water the condensation latent heat from it. The water condensed in the secondary heat exchanger 5 is collected into a condensed water collecting part 7, being led to a drain directly, by a connecting pipe 8. With such an arrangement, a neutralizer is unnecessary to the condensed water, and a material to treat surface is also unnecessary to the other parts, although heat-resistant material is necessary to treat the surface of a primary heat exchanger 3. |
