| 摘要 |
The invention relates to a method for producing nitric acid from ammonia and oxygen containing gas applying the single pressure or dual pressure process characterized in that during the start up and/or shut down of the nitric acid plant a process gas is flowing through a process gas cooler (3) and/or a feedwater preheater (2) which process gas is heated in the process gas cooler (3) and/or in the feedwater preheater (2) and is conveyed through at least one heat exchanger (5 4) located downstream of the process gas cooler (3) and/or the feedwater preheater (2) in order to transfer thermal energy from the heated process gas to a residual gas. The invention further relates to a device for carrying out the method. By means of said methods and/or devices a freezing of the residual gas turbine can effectively be prevented. |
