浸出车间汽提预冷凝器设计及节能效果分析Stripper pre-condenser design and energy-saving analysis in leaching plant

Abstract

节能降耗对提升浸出车间生产线竞争力具有重要的意义。汽提塔气相温度可达95 ℃，其中含有49%的水蒸气和51%的正己烷。研究汽提塔气相冷凝特性发现，在操作压力为35 kPa下，温度从95 ℃下降至40 ℃的过程中，正己烷不会发生冷凝，水蒸气从70 ℃开始冷凝，温度降至54 ℃时，冷凝率可达88%。据此，通过增加汽提预冷凝器可对冷凝产生的热量进行回收，以日处理1 000 t 大豆浸出车间为例，通过换热器设计软件EDR对汽提预冷凝器进行设计、选型、校核，同时对节能效果进行评价。结果表明，通过设计、选型，换热面积为55 m2、型号为BEM 500×4 500 mm的列管换热器可以将新鲜溶剂温度从48 ℃加热至58 ℃。分析节能效果发现,浸出车间增加汽提预冷凝器，吨大豆可节约蒸汽8.2 kg、节约电量0.1 kW·h，具有很高的投资价值。 Energy-saving and cost-reducing have great significance for improving the leaching plant production line competitiveness. The temperature of stripper vapor could reach 95 ℃， which including 49% water steam and 51% n-hexane. By studying condensation characteristics of the stripper vapor, it found that n-hexane did not condense when the temperature reduced from 95 ℃ to 40 ℃under the pressure of 35 kPa, while water steam begined to condense at 70 ℃and the condensation rate could reach 88% as the temperature reduce to 54 ℃.Therefore, the heat generated by condensation could be recovered by adding a stripper pre-condenser. The stripper pre-condenser was designed, selected and calibrated by the heat exchanger design software EDR with the daily processing of 1 000 t soybean leaching plant as an example, and the energy-saving effect was also evaluated.The results showed that through the design and selection, the column heat exchanger with a heat transfer area of 55 m2and the model of BEM 500×4 500 mm could heat the fresh solvent from 48 ℃ to 58 ℃.Adding the stripper pre-condenser in leaching plant could reduce the steam and electricity of 8.2 kg and 0.1 kW·h, respectively, which had great investment value.

Keywords

• 汽提预冷凝器;蒸汽耗量;edr;节能降耗
• stripper pre-condenser；steam consumption； edr；energy-saving and cost-reducing