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A novel approach is proposed for applying cool thermal storage to reduce the on-peak demand of a water-cooled chiller. By charging the store at night via a cooling tower, and using this water to supply the condenser of a chiller during on-peak hours, cooler than normal water is supplied to the chiller. A feasibility study of this system was conducted using TRNSYS — a transient simulation modeling program examining varying capacities of cooling tower and thermal store volumes. These systems were tested using geographic weather data that demonstrated conducive diurnal changes in wet-bulb temperature (Twet). Results suggest that the use of cool water thermal storage in this way can reduce both on-peak energy demand and on-peak power use by as much as 35%. System optimization is dependent on the thermal storage efficiency, the capacity of the cooling tower, and the diurnal change in Twet. 相似文献
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采用抽芯、换芯等方法对发生泄漏的丙烯冷凝器进行快速修复后 ,设备重新投用 ,为同类冷凝器的快速修复提供一可借鉴的思路。 相似文献
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《International Journal of Hydrogen Energy》2023,48(50):19279-19296
Hydrogen-enriched natural gas (HENG) has attracted widespread attention due to its lower pollutant emissions and industrial decarbonization in the past decades. HENG combustion boosts the water content in the flue gas, which is highly favorable for condensing boilers to recover additional latent heat. The energy saving and thermal performance of a condensing boiler burning HENG were evaluated at a constant heat load of 2.8 MW in this study. The variations in combustion products and boiler efficiency were investigated based on the material balance and energy conservation. The heat transfer calculations were employed to evaluate the thermal performance of boiler heating surfaces. The energy recovery performance of the condenser was assessed via a thermal design method. Results show that H2 enrichment enhances the radiation intensity of the flame due to the incremental triatomic gases with higher emissivity in the furnace. The heat absorption ratio increases with H2 enrichment in the radiative heating surface, while it shows a reverse tendency in the convective heating surface. The condensing boiler efficiency based on lower heating value increases from 101.83% to 110.60%, the total heat transfer rate of the condenser increases from 2.77 × 105 W to 4.61 × 105 W, and the total area required decreases from 46.45 m2 to 42.16 m2, as the H2 enriches from 0 to 100% under the exhaust flue gas temperature of 318 K. Although the amount of recoverable heat in the exhaust flue gas increases considerably after H2 blending, the original condenser with natural gas as the designed fuel could meet the requirements of the heat recovery for HENG without increasing the extra heating surface. When the H2 fraction is enriched from 0 to 100%, CO2 emission intensity drops from 6.05 × 10−8 kg J−1 to 0. This work may offer some theoretical references for the application and generalization of HENG condensing boilers. 相似文献