How much electricity can 1 ton of steam generate?
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Gentlemen, I have a question: How much electricity can be generated from 1 ton of saturated steam at 3.0 MPa (A)? (Based on current technology, no matter what method is used, such as turbines or screw expanders, how much can actually be achieved?) ) I read a description of the plan; it uses screw expanders to generate electricity, with a total power output of 140 kwh. I don’t understand how that works. I would appreciate some guidance from an expert.
1 ton of saturated steam at 3.0 MPa (A) can generate 4500----5000 KW of electricity per hour
Your claim is exaggerated; the 140kw figure mentioned earlier is more reliable
The exact amount of electricity that can be generated depends on the efficiency of the power generation equipment; it is recommended to consult the equipment manufacturer. In fact, if you are aware of the typical efficiency of power generation equipment, you can also make calculations based on the enthalpy difference between the steam inlet and outlet
1 ton of saturated steam at 3.0 MPa (A) can generate 150 KW per hour of electricity; generally, it is assumed that 6 tons of steam at 3.0 MPa can generate 1000 KW per hour.
This post was last edited by arpcd on 2015-6-16 at 14:24. It’s easy to estimate; with a basic understanding of thermodynamics, one can calculate it. By using the concept of (exergy), or available energy, Ex = (H – H0) – T0*(S – S0), where H0 and S0 are respectively the enthalpy and entropy of water in its ambient state. The so-called exergy can be understood in this way: for any heat source, the maximum amount of electricity that can be generated from it is the exergy, as the exergy efficiency of electricity is 100%. The environmental conditions can be set at 1 standard atmosphere and 45°C (for both screw compressors and steam turbines, 45°C is the lowest temperature that cooling water can reach). The values are H0 = 188.5 kJ/kg and S0 = 0.6386 kJ/kg·K. For your heat source, which is saturated steam at 3 MPaA, the values are H = 2803.3 kJ/kg and S = 6.1858 kJ/kg·K. Therefore, Ex = (2803.3 – 188.5) – 318.15 * (6.1858 – 0.6386) = 850 kJ/kg. With a steam flow rate of 1 ton, the maximum power generation possible (as this represents the thermodynamic upper limit) is: W = 850 * 1000 / 3600 = 236 kWh. In other words, one ton of saturated steam at 3 MPaA can generate up to 236 kWh of electricity. In actual steam turbines or screw compressors, the thermal conversion efficiency is effective; in other words, there is an internal efficiency, which generally ranges between 0.6 and 0.7. It is said that Americans have managed to achieve an internal efficiency of 74% for screw compressors, which is an impressive figure. When mechanical efficiency and generator efficiency are also taken into account, these efficiencies can be quite high, usually above 90%. Assuming an overall efficiency of 60% for all three factors, the final power generation amount is W = 236 * 0.6 = 142 kWh. Does this match the figures you had? It seems that the solution you saw uses American-made screw expanders, which are commonly used in China as well.
When 3.0 MPa(A) saturated steam is used in screw expanders, the thermal-to-work conversion efficiency of well-made screw expanders in China is approximately 18%, which represents the proportion of heat that can be converted into electricity. 3.0MPa (A) saturated steam enthalpy 2725 kj/kg = 2725000 kj/t. 2725000*18%/3600=136.25KW. Relatively reliable.