| 摘要 |
<p>A method of minimising combustion operation losses includes measuring (40) a load index for the combustion operation which is proportional to the fuel demand or the output thereof, measuring an amount proportional to the air heating losses of the combustion operation and measuring an amount which is proportional to the fuel loss of the operation. The air heating loss is measured by multiplying (34) a flue temperature (30) by an amount of unburned oxygen in the flue gas. This quantity is multiplied (42,44) by a cost factor for such air heating and the load index. The fuel loss is obtained by measuring (46, 48, 50) an amount of by-product in the flue gas as well as the opacity of the flue gas. These are multiplied (56, 58, 60) by appropriate cost factors which in the case of opacity is proportional to a fine that would be due for violating certain limits for the opacity. Minimum values are found for the fuel loss and air heating loss quantities, as air demand to the combustion operation is changed. A minimum for the sum of the fuel and air heating losses is also obtained with the air demand of the combustion operation being set so that all of the losses are as low as possible. In this way the costs of undesired air heating, unburned by-products as well as potential violation of flue gas characteristic limits are utilised in determining the most economical air demand for the combustion operation.</p> |
