| 摘要 |
PROBLEM TO BE SOLVED: To provide an once-through boiler using a biomass fuel to suppress adverse effects such as degradation of boiler efficiency and blockage of a combustion gas flow channel due to combustion ash. SOLUTION: This once-through boiler includes upper and lower headers 17, 16 respectively disposed on upper and lower sections of a combustion furnace 1 in which a combustion chamber 14 is formed, and a group of annular outer water pipes 21 disposed along an inner wall of the combustion furnace, and a group of annular inner water pipes 23 disposed inside of the group of outer water pipes at an interval in a state of being connected with the upper and lower headers at upper and lower end sections. First opening sections 25 are respectively formed between the inner water pipes 19 of the group of inner water pipes, a combustion gas flow channel 24 communicated with the combustion chamber is formed between the group of inner water pipes and the group of outer water pipes, second opening sections 26 communicating the combustion gas flow channel and an exhaust gas passage are respectively formed between the outer water pipes 18 of the group of outer water pipes, and R sections 18a gradually directing to an inner wall side upward from a connecting section with the lower header, are formed at lower end sections of the outer water pipes 18. COPYRIGHT: (C)2011,JPO&INPIT |
