Batch process: A process in which the materials or work are stationary at one physical location while
being treated is termed as batch process. eg: annealing of steel, coke making in coke ovens, furnaces in
foundries, batch reactor in chemical plants.
Batch process are most often of the thermal type where materials are placed in a vessel or
furnace and the system is controlled for a cycle of temperatures under controlled pressure for a period of
time. It is always defined by temperature, pressure or associated conditions such as compositions. Its
degree of freedom is well defined .
The purpose of such processes is to produce one or more products at
- A given composition
- A maximum amount
- Best economy( least materials, energy and time)
Example for batch Process
The batch process has the following advantages versus the continuous process:
- Flexibility when the feed water quality changes
- System recovery can be maximized batch by batch
- Cleaning is easily implemented
- Simple automatic controls
- Permeate quality can be controlled by termination of the process
- Permeate quality can be improved by total or partial second-pass treatment
- Favorable operating conditions for single (or low number) element systems, because the membranes are only in contact with the final concentrate for a short time
- Expansion is rather easy
- Lower investment costs
The disadvantages are:
- No continuous permeate flow
- No constant permeate quality
- Large feed tank required
- Larger pump required
- Larger power consumption
- Longer residence time for feed/concentrate
- Higher total running costs