气液固三相流载气蒸发的抗垢性能

SCALE INNIBITION OF GAS-LIQUID-SOLID THREE-PHASE GAS CARRYING EVAPORATION

分析了化工设备换热面上碳酸钙碱性污垢生成及其影响因素,认为液体在加热壁面上的过热是导致碳酸钙碱性污垢沉积的重要原因,降低料液在加热壁面上的过热度可收到明显的防垢抗垢效果。在蒸发器加热管内引入少量的惰性气体(载气)与流态化固体颗粒,使之形成气液固三相流载气蒸发,可显著强化传热,降低料液在加热壁面上的过热度。以碳酸钙模拟工业硬水的实验结果表明,气液固三相流载气蒸发过程表现出明显的防垢抗垢效果,且具有一定的在线清洗作用。

The formation CaCO3 scale on heat transfer surface is analyzed. The superheat of liquid on heating wall is considered as one of the key factor. Heat transfer and scale inhibition were studied of gas-liquid-solid three-phase Gas Carrying Evaporation (GCE) which was formed by introducing a small amount of inert gas (the carrying gas) and solid particles into flow boiling liquid. The experimental results show that heat transfer is much enhanced and the superheat of liquid at heating wall is evidently lowered with the introduction of carrying gas and fluidized solid particles. Scaling and fouling problems can be effectively inhibited in the three-phase GCE process and 'on-line cleaning' of the heating surface can be realized.