Effect of Boiling Point

Recently, major synthetic oil producers in Western Canada have switched from atmospheric bottoms to vacuum resids for processing bitumen. This raises the question of what impact this change might have on the coke induction period during thermal processing of these materials. To address this question, Athabasca bitumen (+343°C) was fractionated using Distact distillation into four distillates and resids.The selected boiling point cuts were 525°C, 575°C, 625°C, and 675°C. The coke induction periods of bitumen 

Fig 7a Semicoke formation from asphaitenes Fig 7b Semicoke formation from resins 

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The specific heat capacity may be taken as constant at 4.18 kJ/kgK, and the effects of boiling point rise and of hydrostatic head may be neglected. 

A salt solution at 293 K is fed at the rate of 6.3 kg/s to a forward-feed triple-effect evaporator and is concentrated from 2 per cent to 10 per cent of solids. Saturated steam at 170 kN/m2 is introduced into the calandria of the first effect and a pressure of 34 kN/m2 is maintained in the last effect. If the heat transfer coefficients in the three effects are 1.7, 1.4 and 1.1 kW/m2K respectively and the specific heat capacity of the liquid is approximately 4 kJ/kgK, what area is required if each effect is identical Condensate may be assumed to leave at the vapour temperature at each stage, and the effects of boiling point rise may be neglected. The latent heat of vaporisation may be taken as constant throughout. 

Adding an impurity to a solvent makes its liquid phase more stable through the combined effects of boiling point elevation and freezing point depression. That s why you r irely see bodies of frozen salt water. The salt in the oceans lowers the freezing point of the water, making the liquid phase more stable and able to sustain temperatures slightly below 0°C. 

Smith studied the effect of boiling point differences of various cuts of hexane on miscella (218). Smith also determined the vapor pressure of hexane-soybean oil solutions at high solvent concentrations (211). When making stripping calculations, one should be aware that the last portions of solvent to vaporize consist of higher boiling constituents in that particular cut of solvent. 

Figure 2.3.2. Effect of boiling point on solvent viscosity.

EFFECTS OF BOILING POINT RANKINGS ON THE DESIGN OF REACTIVE DISTILLATION... 

We use quaternary ideal reactive distillation systems to illustrate the effects of boiling point ranking on conceptual design. Consider the following second-order liquid-phase reversible reaction ... 

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