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https://bbs.hcbbs.com/forum.php?mod=attachment&aid=MzYxMjk3OHxhNTlkNTIwZHwxNzY4MjczNDUzfDQ5MDUzMDh8NTcwOTExNg%3D%3D&noupdate=yes Steam turbines are often used in steam power generation, or to drive compressors and similar devices. The thermal efficiency of a steam turbine determines the output power as well as the amount of steam consumed. Therefore, improving the thermal efficiency of steam turbines helps companies save energy; especially under the same load conditions, it is possible to reduce steam consumption, thereby achieving energy savings and emission reductions. How can the thermal efficiency of steam turbines be improved? I. First, analyze the thermal efficiency: The operating condition of the steam turbine can be monitored and analyzed through DCS. The following indicators can be primarily analyzed: 1. Condenser negative pressure. The steam that passes through the steam turbine needs to be discharged under negative pressure via a condenser. The negative pressure in industrial steam turbine condensers is generally between 92–96 Kpa. If the negative pressure in your steam turbine is only 86 Kpa, it can be assumed with certainty that the thermal efficiency of this steam turbine is somewhat low. The negative pressure of the steam turbine is usually indicated on the DCS. 2. Exhaust temperature. The exhaust steam from steam turbines is generally cooled by circulating water; therefore, the lower the exhaust steam temperature compared to the temperature of the circulating water, the better the cooling of the steam, and the easier it is to create a negative pressure. The outlet temperature of the circulating water is generally between 30-40°C, so the exhaust steam temperature should also be as close to this value as possible. For example, if the exhaust temperature in your system is 48°C, then the temperature is certainly too high, and the thermal efficiency will likely not be good. 3. Temperature difference. For example, if the exhaust temperature is 48°C and the outlet temperature of the circulating water is 35°C, the difference between these two temperatures is the temperature difference. The difference at this end should be as small as possible; if it exceeds 10°C, that is definitely not good. Through indicator analysis, it is easy to determine whether one’s steam turbine has a high thermal efficiency and whether there is any steam waste. Secondly, preventing scaling in the condenser: A low thermal efficiency of steam turbines is largely due to poor quality of the circulating water, which causes scaling in the condenser. This reduces the heat exchange efficiency of the condenser, thereby preventing the exhaust steam from being cooled in a timely manner. If the water hardness reaches 500 mg/L, the scale thickness can reach 2–3 mm per year, and the thermal efficiency of the condenser will decrease by 20–30% or even more. At this time, scale inhibition and prevention can be achieved using microwave equipment; by installing such equipment on the inlet pipe of the condenser’s circulating water, scale inhibition and prevention can take place in real time. As the heat transfer efficiency of the condenser improves, the thermal efficiency of the turbine will also increase. (Microwave equipment inquiries: TigerPeng2014) III. Significant economic benefits: The anti-scaling function of the condenser yields the greatest economic advantage by allowing for significant savings in steam usage. Based on experience, for every 1 kPa increase in the negative pressure of the steam turbine condenser, the thermal efficiency of the steam turbine increases by 1%. In other words, this results in a savings of about 1% in steam usage. Based on the estimated annual steam cost of 40 million for the steam turbine, an increase in negative pressure of 3-5% can result in savings of around 1-2 million per year. (WeChat: TigerPeng2014)