Feed tray location Particularly when the number of trays is small, the location of the feed tray has a marked effect on the separation in the column. An estimate of the optimum location can be made with the Under-wood-Fenske equation (13.116), by applying it twice, between the overhead and the feed and between the feed and the bottoms.The ratio of the numbers of rectifying Nr

by using the optimum feed tray locations for each feed composi-tion can be quite significant [Luyben, 1975]. In this case, for ex-ample, the V/F ratio calculated by using the 32nd feed tray is 10% higher than that using the 24th feed tray for the feed composition of 0.4. As shown in the middle curves of Fig. 6, the optimum feed tray location of

First, steady-state analysis is carried out to find the optimal feed trays as measurable load variable varies. Then, a control structure is proposed to 

Therefore, when a mass feed stream is considered, whatever its thermal condition, such optimum feed location consideration is consequent with the assumption 

2001. 8. 5. · by using the optimum feed tray locations for each feed composi-tion can be quite significant [Luyben, 1975]. In this case, for ex-ample, the V/F ratio calculated by using the 32nd

5 Reactive Column with Optimum Feed Tray Locations DESIGN AND CONTROL OF COLUMN/SIDE REACTOR SYSTEMS [Pg.446] For the case with aago = 0.95, the lower feedstream is moved from tray 15 up to tray 29 and the upper feedstream is moved from tray 82 down to tray 68.

The MINLP minimizes the total annual cost subject to a rigorous tray-by-tray model. The solution of this MINLP yields the optimal number of trays, the optimal feed rates, and the optimal feed tray locations. The liquid holdup per tray, the reflux ratio, and the temperature and composition profiles within the column are optimized as well.

The optimum feed tray location is determined for each selected number of total trays by finding the feed location that minimizes reboiler duty. [Pg.459] LZD)jnjjj from simulations with 100

This model determines the optimum location of feed plates in a distillation column with 7 ideal stages, a total condenser and a kettle-type reboiler. 'temperature of tray i' feed(i) 'feed stream entering tray i' r 'reflux ratio' p1 'top product rate' p2 'bottom product rate'; Variable hl(i) 'molar sp.enthalpy of liquid in tray i' hv(i

trays, and the goal is to select the optimal feed tray location. Figure 1 shows that a superstructure that can be postulated is one where simply the feed is 

With careful selection of the feed tray location, significant TAC as well as energy savings for the operation of this column can be realized. Previous chapter