Evaporation triple effect

Figure 16. Sweetwater evaporation (triple effect with vapor compression) (11).

Type evaporator Triple effect, backward Triple effect, backward Triple effect, backward Triple effect, backward... 

Fig. 30. Flow diagram of a triple-effect caustic evaporator.

A liquid with no appreciable elevation of boiling-point is concentrated in a triple-effect evaporator. If the temperature of the steam to the first effect is 395 K and vacuum is... 

A triple-effect backward-feed evaporator concentrates 5 kg/s of liquor from 10 per cent to 50 per cent solids. Steam is available at 375 kN/m2 and the condenser operates at 13.5 kN/m2. What is the area required in each effect, assumed identical, and the economy of the unit ... 

A triple-effect evaporator is fed with 5 kg/s of a liquor containing 15 per cent solids. The concentration in the last effect, which operates at 13.5 kN/m2, is 60 per cent solids. If the overall heat transfer coefficients in the three effects are 2.5, 2.0, and 1.1 kW/m2K, respectively, and the steam is fed at 388 K to the first effect, determine the temperature distribution and the area of heating surface required in each effect The calandrias are identical. What is the economy and what is the heat load on the condenser ... 

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. 

A feed-forward triple-effect evaporator is to concentrate 5 % NaOH to 50 % NaOH. 

Fig. 21. Reordered occurrence matrix for the triple effect evaporator system illustrated in Fig. 20.

The classical procedure to solve the triple effect evaporator problem is as follows ... 

Equations and Unknown Variables for Triple Effect Evaporator... 

Figure 14.5. Forward-feed arrangement for a triple-effect evaporator...

Figure 14.8. Effect of feed temperature on the operation of a triple effect evaporator (a) Forward feed...

Reavell(17) has given a comparison of costs for the concentration of a feed of a heat-sensitive protein liquor at 1.70 kg/s from 10 per cent to 50 per cent solids, on the basis of a 288 ks (160 hour) week. These data are shown in Table 14.3. It may be noted that, when using the double-effect evaporation with vapour compression, a lower temperature can be used in the first effect than when a triple-effect unit is used. In determining these figures no account has been taken of depreciation, although if this is 15 per cent of the capital costs it does not make a significant difference to the comparison. 

WEBRE, A. L. Chem. Met. Eng. 27 (1922) 1073. Evaporation — A study of the various operating cycles in triple effect units. 

A triple-effect evaporator concentrates a liquid with no appreciable elevation of boiling point. If the temperature of the steam to the first effect is 395 K, and vacuum is applied to the third effect so that the boiling point is 325 K, what are the approximate boiling points in the three effects The overall heat transfer coefficients may be taken as 3.1, 2.3, 1.3 kW/m2 K in the three effects, respectively. 

Edmondson, K.H. Disposal of antibiotic spent beers by triple effect evaporation. Proceedings of the 8th Industrial Waste Conference, Purdue University, West Lafayette, IN, 1953 46-58. 

Figure 8.17. Forward and backward of liquid flow with respect to steam flow in triple-effect evaporators, (a) Forward flow of liquid by action of pressure differences in the vessels, (b) Backward-pumped flow of liquid through the vessels.

Fig, 1. Triple-effect evaporator used in concemraiing soda solutions and preparation of solid sodium hydroxide... 

Fig. 3. Triple-effect steepwater evaporator. The third effect (forced circulation) Is shown in background second effect (falling film, recirculating) is middle unit. The first effect vapor head is shown in foreground. (Swenson. Whiting Corp)...

The authors pose the problem as a multiple objective function problem, and, in their example, consider the two competing objectives of total evaporator heat exchanger area and steam usage. The paper is really a clever way of eliminating a number of flow patterns as never being candidates for the optimal solution regardless of the relative importance of the cost for area versus steam costs. For a particular triple effect example problem, they show that, depending on the liquid feed temperature, 3,... 

The effluent from the magnesium hydroxide process is a 25 percent calcium chloride brine. The water in the brine is boiled away with steam in triple-effect vacuum evaporators to make 32-45 percent CaCl2. Alkali chlorides precipitate in the evaporators and... 

A triple effect evaporator is designed to reduce water from an incoming brine (NaCl + H2O) stream from 25 wt % to 3 wt %. If the evaporator unit is to produce 14,670 lb/hr of NaCl (along with 3 wt % H2O), determine ... 

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