The document discusses a process for producing hydrogenated palm oil through the hydrogenation of palm oil using a Raney nickel catalyst. It then poses 5 questions related to various aspects of the process: 1) The immediate concern for pumping hot oil from the feed tank to the reactor is cavitation due to vapor bubbles forming under low pressure. Installing a control valve and reducing pump speed can help prevent cavitation. 2) Vacuum in the reactor is needed to prevent overpressure and reduce the flash point for safe catalyst loading. Failure of the vacuum unit poses a fire hazard. 3) A closed-loop temperature control system using a sensor and controller can maintain the reaction temperature as it increases with decreasing iod

1. By Team Inaishigi
Ashutosh Mishra Uday
Ashna Gautam
Nutesh Y
Industrial
Problem
Solving

2. A plant located at Kandla; Gujarat produces 100 TPD of Hydrogenated Palm Oil. The reaction
parameters are specified below: - Reaction Temperature: 200°C Reaction Pressure: 20 bar
Hydrogenation reaction is highly exothermic and is carried out in the presence of Raney Ni
Catalyst. The block diagram of the process is as shown below: -
The Problem Statement...

3. The feed tank (A) under skirt support, is
under partial vacuum to de-aerate the
incoming oil. The oil is heated with the help
of steam in coils. If the batch is transferred
from (A) to reactor (B) by a pump. What will
be the immediate cause of concern related
to the selection of pump and its operation?
Suggest a viable way to overcome the
same.
Question 1:

4. ➔ The immediate cause of concern would be cavitation. The existence of vapour
bubble inside the liquid stream at low pressure regions can reduce pumping
efficiency, damage the pump and make unnecessary noise.
➔ High temperature oil which is coming from the feed tank to the pump is more
prone to cavitation as in low pressure regions, oil may vapourize to form bubbles
and this cavitation is encountered.High temperatures allow vapor cavities to
form with less of a pressure drop
➔ NSPH Value: depends on vapour pressure
➔ It measures of cavitations higher the NPSH lesser prone to cavitation
➔ High temp lowers nsph value.
SOLUTION 1

5. We can installed control system on centrifugal pump and just throttle back on
the valve control.
some tips to prevent cavitation due to vaporization include:
➔ NPSHa > NPSHr + 3 ft or more safety margin
➔ Raise liquid level in suction vessel
➔ Reduce motor RPM
➔ Use impeller inducer
➔ Increase diameter of the eye of impeller
SOLUTION 1 CONTINUE...
SOLUTION TO PREVENT CAVITATION

6. Once the oil is available in the reactor (B),
catalyst is dosed, and vacuum unit
connection to this reactor is switched off.
Hydrogen is introduced in metered
quantity until the required reaction
pressure is attained. Why do we require
vacuum in this reactor? What would be the
consequence of failure of vacuum unit?
Question 2:

7. ➔ The vacuum in reactor unit is required to prevent overpressure of the
tank and reduce flash point of the oil
➔ Vacuum environment helps with catalyst loading.
➔ ( as flash point is increased by low pressure of the vacuum)
➔ If vacuum unit is not working properly then there is a potential fire
hazard inside the reactor.
➔ Overpressure may cause unnecessary strain on the reactor shell and it
may even burst
SOLUTION 2

8. Hydrogenation is carried out to reduce the
IV (Iodine Value) of feed oil. During the
reaction, with every unit drop in IV of oil,
there is possible rise in temperature by 2°C.
Suggest a control logic/algorithm by which
the reaction temperature can be
maintained.
Question 3:

9. A closed loop temperature control system can be added on the rector which reduces the
constant increase in temperature.
ALGORITHM
Control loop algorithm
A temperature sensor, usually a thermostat is connected to the reactor which constantly
measures the temperature of the reaction
A given value of the temperature is set already by us at 200c, the error is calculated as set
point - measured temperature
The controller analyses the error
if there is a positive error, then the
measured temperature is lesser than
the desired temperature, and hence a
signal to increase the reactor
temperature by the error margin is
given out by the controller to the TCV
if there is a negative error, then the
measured temperature is more than
the desired temperature, and hence a
signal to decrease the reactor
temperature by the error margin is
given out by the controller to TCV

11. After completion of batch of oil, how can
we vent the Hydrogen out from the Head
space of the reactor?
Question 4:

12. ➔ Excess amount of hydrogen gas, if discarded is vented to
atmosphere by mixing with steam, on the top head of the
reactor.
➔ However, the excess hydrogen is again fed back to use
again in the reactor for another batch of hydrogenation
reactions after going through down stream processing.
SOLUTION 4

13. The plant owner intends to reduce the load
on the boiler. Suggest a suitable scheme
for heat recovery. The temperature profiles
are as given below: -
Feed Temperature-60 degree C
Inlet Temperature to (A)- 140
Reaction Temperature in (B)-200
Filtration Temperature (C)-120
Final Product Temperature (D)-70 degree C
Question 5:

14. ➔ Heat wasted in reactor can be taken to the steam chamber
BY A JACKET SURROUNDING THE REACTOR which carries
steam to the main feed tank, thereby using this energy to
heat up the feed.
➔ We can utilize the heat of the exothermic reaction given
out, by enveloping the reactor with steam pipelines which
conduct the heat carried in the reaction
➔ This pipe can take hot steam back to the feed again to be
used.
➔ Energy which was wasted before can be utilized again and
the load on the boiler reduces.
SOLUTION 5

16. THANK YOU