9. Simulation and optimization

Simulation and optimization are the act of obtaining the best result under given circumstances. Optimization can be defined as the process of finding the conditions that give the maximum or minimum value of a function. Process optimization is the discipline of adjusting a process so as to optimize some specified set of parameters without violating some constraints. The chemical industry has undergone significant changes during the past 25 years due to the increased cost of energy,

We have set the reboiler temperature at 70°C which is close to boiling point of methanol. However it varies as the reaction proceeds. The composition of methyl acetate obtained experimentally is 96%. The pressure of the top stage varies between

108 and 163 mmHg and that of reboiler varies between 249 and 300 mmHg.

Contents Characteristics and conditions No. of stages 10 including reboiler and condenser

Catalyst Amberlyst-15 (Acidic ion-exchange)

) 0.99

Feed Methanol Acetic acid

3 50°C Atmospheric 0.03

6 50°C Atmospheric 0.03

Rectifying section 7–8 Reactive section 3–6 Stripping section 1–2 Packing used HYFLUX

Catalyst granularity 10–100 μm Average particle diameter (m) 7.4 <sup>10</sup><sup>4</sup>

Macro porosity of catalyst 0.32 Condenser type Total condenser

Reflux ratio 5

Characteristics of packed reactive distillation column.

Figure 4.

Pilot-scale reactive distillation column.

Distillation - Modelling, Simulation and Optimization

Apparent density (g/cm3

• Feed stage • Feed temperature • Feed pressure • Feed flow rate (L/min)

Table 2.

100

increasingly stringent environmental regulations, and global competition in product pricing and quality. One of the most important engineering tools for addressing these issues is optimization. Modifications in plant design and operating procedures have been implemented to reduce costs and meet constraints, with an emphasis on improving efficiency and increasing profitability. Optimal operating conditions can be implemented via increased automation at the process, plant, and company levels, often called computer-integrated manufacturing. Computers and associated software make the necessary computations feasible and cost-effective [22–25].
