Chemical Equipment Sizing

Sizing of chemical equipment? Well , the common equipment required to process oil & gas, chemical & petrochemical such as Reactor, Distillation Column, Pressure Vessel/Gas Scrubber, Compressor, Pump.

How to design Reactor?
1.Perform calculation based on rate of reaction to obtain volume of reactor.
2.Key in the  data into simulation software (Hysis,Icon).
3.Determine operating parameter (e:g pressure & temperature).
4.Perform sizing calculation.
5.Perform mechanical design
6.Proced with costing , technical drawing and lastly start up & shut down procedure

How to design Distillation Column?
Distillation column separates the liquid mixtures into their components. Upper section is called rectifying section and lower one is called stripping section. The liquid having lower boiling point is obtained as a bottom 
product and the liquid of a higher boiling point obtained as a top product.

1.Choosing tray column or packed column. Tray is the common one as it is designed to handle wider range of liquid & gas flowrate, easier to clean as in the case of fouling.
2.Choosing tray either bubble cap (expensive), sieve trays (cheapest) or valve plates based on cost , efficiency and pressure drop.
3.Conduct simulation (Hysis, Icon), Select operating condition.
4.Deteremine number of equilibrium stages (Fenske Equation,MCCabe thiele method, VLE).
5. Sizing the internal column (Diameter, no of real stages).
6. Perform mechanical design (vessel & internal fittings,head, closure,shell thickness, nozzle)
7. Proced with costing , technical drawing and lastly start up & shut down procedure .

How to design Gas Scrubber?
1. Let say the input of inlet contained natural gas & water.The vessel will separate these 2 component by forces usually gravity.
2.Usually demister pad inside gas scrubber is used to improve efficiency of separation where it is use to resist the droplet of water that are not fully vapourized to enter top product.
3. Calculate the settling velocity,
4.Calculate the diameter and total height.
5. Perform mechanical design (Nozzle)

How to design heat exchanger?
1. HE is used to transfer heat between hot and cold stream.
2. Tube side preferable for fluid that has high presure, high temperature.Fluid having more corrosive nature and higher fouling factor is passed through tube side because we can easily replace the tube after maintenance but if the shell get corroded it will be more economical to replace or maintain it.
3. Cooling water will enter tube side while reactor effluent enter shell side.
4.Determine physical properties of tube and shell side (temperature, specific heat,thermal conductivity,density, viscosity)
5.Calculate heat duty Q=mcT
6. Calculate heat transfer area U=Q/AT
7. Calculate tube side velocity, shell diamter



How to design Compressor ?
1. Compressor is use to compresses gas from 1 point to another point.
2. Calculate pressure,volume & work done.
3. Calculate compression ratio.
4. Calculate power required 7 electrical power.