How much flash vapor can be generated by reducing the pressure of 0.8Mpa saturated condensate to 0.3Mpa? How much value does this portion of flash steam have?

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Calculation formula = (Enthalpy of saturated condensate at 0.8 Mpa – Enthalpy of saturated condensate at 0.3 Mpa) / Enthalpy required to convert saturated condensate at 0.3 Mpa into saturated steam. Parameter 1: The enthalpy of saturated condensate at 0.8 Mpa is 743 kl/kg. Parameter 2: The enthalpy of saturated condensate at 0.3 Mpa is 605 kl/kg. Parameter 3: The enthalpy required to convert saturated condensate at 0.3 Mpa into saturated steam is 2738 kl/kg. Calculation formula = (743 – 605) / 2738 ≈ 0.05. In other words, when saturated condensate at 0.8 Mpa is reduced to 0.3 Mpa, 0.05 kilograms of steam can be produced per kilogram of condensate; the flash rate is 5%, which means approximately 5% reduction in the amount of fresh steam required at 0.3 Mpa. When other energy-saving measures are taken into account, the actual savings rate ranges from 8% to 10%. 【Conclusion】: Accurately calculating the flash volume is rather complicated, as it requires reference to tables of enthalpy values for steam condensate. A common simplified method used in the industry is that for every 1° decrease in condensate temperature, the flash volume increases by 0.15%. Using the data from above as an example, the simple calculation formula gives: (176–143) × 0.15% = 0.0495; the deviation from the precise calculation is only 1%. ● What is the value of recovering flash steam? Flash steam recovery holds great economic value; recovering 1 ton of flash steam can save 1 ton of fresh steam! Taking the example above, assuming a steam consumption of 6 tons per hour at 0.8 Mpa and a steam cost of 180 yuan per ton, then—the value of the recovered flash steam (at 0.3 Mpa) per month is: 6 tons/hour × 0.05 × 180 yuan/ton × 24 hours × 30 days ≈ 40,000 yuan. The value of the recovered flash steam and other waste streams per month is: 6 tons/hour × 0.08–0.1 × 180 yuan/ton × 24 hours × 30 days ≈ 62,000–78,000 yuan. ● When the pressure of the flash steam is too low to be directly reused in the steam supply pipeline, auxiliary \"waste steam pressure-boosting\" techniques are required to maximize the utilization of the flash steam. If you, dear readers, have any further insights on this matter, feel free to get in touch with the editor to discuss it!