May I ask about the steam consumption issue of the turbine?
Thread Content
There is a question that has been bothering me, and I would like an answer to it: Under the condition that the final parameters of the exhaust steam remain unchanged, increasing the initial parameters of the steam supplied to the turbine – that is, raising the main steam pressure and temperature before the main steam valve of the turbine – can increase power generation. That is because the pressure is increased, which is equivalent to an increase in the steam inflow (but at the same temperature, an increase in pressure results in a decrease in enthalpy). So, given a constant boiler load and thus a fixed main steam flow rate in the turbine, what is the impact of the steam inlet pressure on steam consumption or power generation?
When the boiler load remains the same, the main steam flow rate of the turbine is fixed. If the steam inlet pressure of the turbine is increased, there are mainly two effects: one is an increase in the mass flow rate of the incoming steam ； Second, it increases the inlet steam enthalpy. Since the power output of a turbine is related to the enthalpy of the steam entering it, increasing the steam inlet pressure can boost the turbine’s power generation capacity. However, if the steam inlet pressure is increased too much, it will result in more internal and thermal losses during the operation of the turbine, thereby increasing steam consumption. Therefore, when selecting the steam inlet parameters for a turbine, it is necessary to take various factors into consideration, including the technical conditions and economic benefits of the boiler, turbine, power plant, and other related elements. .
Increasing the pressure while keeping the temperature constant is equivalent to increasing the enthalpy of the main steam; with the flow rate and other parameters remaining unchanged, the enthalpy drop of the steam within the turbine increases, resulting in higher efficiency