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PROCESS MANUAL

1.3.10

HTM SYSTEM Huitong ChemicalEngineering Technique

Co.,Ltd

This Document and all the information contained therein are and remain the intellectual property of Oerlikon

Bargmag Engineering & Huitong Chemical Engineering Technique Co Ltd. No Part of this document may be

reproduced, stored in retrieval system or transmitted in any form or any means, electronic, mechanical,photocopying, recording or otherwise, neither should it be made accessible nor brought to the knowledge of any

third party. No title, license, copyright, or any other legal rights are granted expressly or implied.

Rev 0 SAI-11154 Page 1 of 12

Table of Contents

Section Contents Page No

1.3.10 HTM SYSTEM 2

1.3.10.1 Leak Test 2

1.3.10.2 Start Up 3

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reproduced, stored in retrieval system or transmitted in any form or any means, electronic,

mechanical ,photocopying, recording or otherwise, neither should it be made accessible nor brought to theknowledge of any third party. No title, license, copyright, or any other legal rights are granted expressly or

implied.


f. After pressurizing the system with compressed air, leak hunting is to be started by

pouring soap solution on the welded joints, flanges, valve glands, open drain or vent

points and other points which are most susceptible for leakages. Soap bubbles would

be formed at the places where the leakage will be present. These are to be marked

properly with the help of chalk or other suitable method. Corrective action is to be

taken to arrest the leaks found during the leak hunting and the pneumatic dwell test

is to be repeated till satisfactory results are obtained.

g.

It is important to note here that once pressure dwell test of the all the individual

system is over the dwell test for all the systems together is to be carried out finally.

h. During the final pressure dwell test, display the system pressure on DCS as precision

of field pressure gauge is generally not enough.

i. If leakage rate is not beyond 0.5KPa /h or system pressure decrease for 24 hours is

not beyond 5%, then pressure dwell test is qualified.

1.3.10.2 Start-up

1. HTM unloading into the storage tanks

a. Arrange the HTM drums near the HTM unloading & Charge Pump.

b. Ensure that the Level Guages/ Level transmitters of the HTM storage vessel

37-VO1, HTM Expansion Tank 37-VO2 and Low Point drain vessel 37-VO3 are

lined up and the low and high level switches/ DCS alarms are functional. Also

ensure that the calibrated gauge is installed at the discharge of the HTM

charge pump 37-PO2.

c. Close the primary HTM expansion vessel 37-V02 HTM supply valve at the

discharge of pump 37-PO2 and open the valve towards HTM storage vessel

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37-VO1. Close the HTM charge pump discharge valve, Vent valve and suction

side unloading point valve. Ensure that the drain points of the all the tanks

are closed and provided with blanks.

d. Close the valve from storage tank 37-V01 to HTM Charge pump 37-PO2.

e. Close the valve from low level tank 37- V03 to HTM Charge pump 37-PO2.

f. Ensure that the air venting path of the HTM storage vessel is free of chocking

in order to diplace the air during filling of the tank.

g.

Connect one end of the flexible unloading hose to the unloading point at the

suction of HTM charge pump 37-PO2 and put other side dipped inside the

HTM drum upto its bottom. Secure both the ends of the unloading hose

firmly to avoid leakages and hose slip-out during unloading.

h. Open the unloading hose isolation valve at the suction of HTM charge pump

and start the pump.

i.

After outlet pressure of supply pump is stable, open the valves from

circulation pipeline to storage tank 37-V01.

j. During the unloading process, monitor the levels of the tanks 37-VO1,

37-VO3 and 37-VO2 to ensure that the HTM is going into tank where it is

intended.

k. After finishing unloading of one drum, close outlet valve of supply pump and

stop the pump.

l. Put the unloading hose into another drums and carry out unlading of the

drums till predetermined level is reached in the HTM storage vessel 37-V01.

m. Same procedure is also to be followed for unloading Biphenyl Ether into its

storage tank 37-VO4 with the help of the pump 37-PO5.

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2. HTM system filling

a. HTM filling is to be carried out only after the successful completion of

pressure dwell test of the whole HTM system followed by its depressurization

HTM Expansion vessel.

b. Ensure that the Level Guages/ Level transmitters, Pressure gauges/Pressure

Transmitters installed in the HTM system are in line and its functional test is

taken. Also ensure that low and high level switches/ DCS alarms are

functional.

c. Prior to starting filling of HTM, all valves of all the individual secondary

systems and the primary system are to be adjusted as directed in the

procedure. This is essential for avoiding any mishap during the filling activity.

d. Open the by-pass valve of the primary HTM header pressure control valve

PV-37221.

e.

Open all valves in primary HTM circulation after the discharge of the primary

pump and ensure that all the drain and vent valves are closed. Also ensure

that the heater outlet pressure safety valves are in line.

f. Open all the primary HTM supply valves of all the secondary systems. Also

open the return valves of these systems. Open all the valves in all the

circulating loops of all secondary HTM systems and close all the drain and

vent valves. However the high point vent valve towards the expansion tank of

each secondary system is to be left open in order to vent all the air in the

system through the expansion vessel.

g. Ensure that all sencondary systems high point vent valves common header is

free from any restriction.(Normally this is done at the time of pressure dwell

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test of individual secondary HTM system)

h. Monitor continuously all the HTM tank levels and also establish the field

monitoring. During the filling activity keep close vigil of all the tank levels as

well as continuous field patrol is necessary.

i. After ensuring HTM low point drain tank to HTM charge pump valve is closed,

open HTM storage tank 37-V01 to HTM charge pump valve

j. Start the HTM charge pump.

k.

Slowly open the outlet valve of HTM charge pump.

l. Open the filling valve in the discharge header of HTM charge pump towards

the expansion tank and start filling the expansion tank. Initially the

expansion tank level will not rise as the all the HTM charged into it will be

filled in the empty primary and secondary systems piping.

m. When all the primary and secondary HTM systems are filled with HTM liquid ,

level in HTM expansion tank will start rising. It is to be increased up to 50%,

after which stop HTM filling of expansion tank. Stop the HTM charge pump

and isolate it. Close the HTM storage tank to HTM charge pump valve.

n. Close HTM supply valves of all the secondary HTM systems and also close the

high point vent valves.

3. HTM system cold circulation

a. Ensure following

1. By-pass valve of the primary HTM main header pressure control

valve PV-37221 is open and inlet and outlet valves are closed.

2. The inlet and outlet valves of the HTM heaters primary HTM line are

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open. Its Safety valves are in line.

3. The inlet valves of HTM primary pump are open and discharge

valves are closed.

4. All the HTM tanks blanketed with nitrogen and the nitrogen valves

closed. The HTM expansion tank is released into the HTM liquid seal

tank.

5. Primary HTM supply and return valves of all the secondary systems

are closed.

b. Monitor continuously all the HTM tank levels and also establish the field

monitoring. During the heating activity, keep close vigil of all the tank levels.

Continuous field patrol is necessary to ensure that no mishap takes place

during the circulation activity.

b. Start the primary HTM circulation pump and start its current monitoring with

its discharge valve closed. As the viscosity of the cold HTM is higher the

pumps can not be run at their normal operating flow rate. The flow rate is to

be set by adjusting the pump discharge valve till the pump current is 90% of

the safe permissible limit.

c. When the outlet pressure of HTM circulation pump is stable, slowly open the

outlet valve of HTM circulation pump keeping close watch on discharge

pressure to ensure that the outlet pressure is not lower than the pump

operating pressure. (Pump Current value should also be lower than the

maximum allowable value). Estabilsh the circulation through primary HTM

header supply and return lines.

d. Switch the circulation pump when the outlet pressure of HTM circulation

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pump is decreased or cavitation is noticed in it. After switching the pump

isolate and clean the suction strainer of the offlined pump and keep it ready

for lineup.

e. Open the inlet and outlet valves of HTM primary header pressure control

valve PV-37221 and gradually close bypass valve. Now control the circulation

pressure through the control valve.

f. Using the same principle as described in the above procedure establish the

cold circulation through secondary systems one after other.

4. Heatup of the Liquid phase HTM system

(Here it is important to note that although the procedures for heatup of the Liquid

and Vapor HTMs are separated, the heatups are carried out simultaneously. The

temperature profile of the all the systems should be kept uniform while carrying

the heatup)

a.

Ensure following

1. Expansion joints, spring hangers and supports are in normal

working state.

2. The fire fighting measures are ready and all the departments have

been informed.

3. Insulation of the whole system has been completed and same has

been audited and certified. The insulation of the flanges and major

welding joints is not to be done before heatup as they are more

susceptible for developing leakages.

4. During heatup there is always a possibility that the leakage may be

developed in the piping systems. Sometimes the leakage is small

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and is not noticed until the insulation surrounding it is completely

drenched with liquid HTM. Insulation soaked in HTM always poses

threat of fire. Therefore at least one qualified person should be

present on each floor round the clock. Similarly, patrolling is to be

done in HTM side and on the piping racks as well.

5. Ensure that the reactors, vessels and pipelines are empty and the

pressure release system of the reactors, pipelines and other

vessels are established as there is always a chance of pressure

buildup during the heating. During first heatup the drains in the

reactors and vessels which will be heated as well as drains in the

pipelines are to be left open.

6. Ensure that all the interlocks of the HTM heaters and CP & Spinning

systems are functional and settings have been done as desired.

7.

Ensure that all the bolts in the HTM systems are coated with high

temperature grease and are tightened to their specified torque

limits.

8. Ensure that the seal cooling and lubrication systems of the

agitators, mechanical seals and additives lances are operational.

9. The material expands when heated up. Therefore markup the lines

and parts of the major equipments. Also leave scope for the

thermal expansion of the equipments as per guidelines in the

mechanical manual.

b. Heatup is to be started only after the chocking frequency of the primary

pumps and secondary pumps is more than 24 hrs with the cold circulation. As

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during heating the chocking frequency will increase due to loosening of the

pipe rust at elevated temperatures.

c. Open fully the secondary systems primary HTM supply control valve

bypasses. Also ensure that the secondary system return valves to primary

circuits are fully open.

d. Due to circulation the temperature of the HTM increases and the pump

discharge valve can be increased further as the current will go down. The

heaters can be fired once the flow rate is increased beyond the minimum

permissible limit.

e. During the first phase of the heatup the temperature is raised upto only 110

OC to remove the moisture and the low boilers from the circulating HTM. This

stage is called as Drying stage. The temperature is to be raised slowly and

the rise rate should not exceed beyond 10 OOO

C/hr.

f.

Pay attention to the liquid level of expansion tank and system pressure in the

process of temperature increasing. The temp is hold at 110 OC for 8 hrs to

allow all the moisture and low boilers to escape from the system.

g. After oven drying is finished, start the dehydration stage. Increase

temperature up to 150200at the rate of 10 OC/hr.

h. Hold temperature at this level at least for 8 hours and observe for the

leakages, pressure buildup and thermal expansions.

i. After dehydration is finished, and condition of the all the equipments and

piping found normal then start increasing the temperature further at the rate

of 10 OC/hr upto 300.

j. Increase the temperatures of the Reactors and other equipments with

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primary and secondary HTM and put the sencondary HTM temperature

control in auto operation after achieving the predetermined temperatures

and control the supply from primary HTM to second HTM with control valve.

k. When the temperature of final polycondensation reactor increased upto

100, rotate its agitator one time per hour, which rotates 1 1/4 rings each

time.

l. Pay attention to the expansion stress of equipment and pipeline in the

process of temperature increasing.

m. Pay attention whether there is leakage in primary and second HTM system, if

there is leakage, online treat it or stop HTM circulation for treatment

according to condition.

n. When HTM system reaches upto the predetermined temperature,

auto-operate the HTM heaters. Here it is important to note that as the load on

the HTM heaters being very low, the heaters would not run continuously and

may have to be switched ON and OFF frequently. To reduce the frequency of

switching ON and OFF the heaters ON/OFF temperature settings can be

widened suitably.

o. Carry out the hotbolting of the equipments after allowing heat soaking

soaking for 8 hours at the normal temperature.

p.

Close all process drains/vents once the primary and secondary HTM systems

are operating in stable condition.

5. Heatup of Gas phase biphenyl ether system.

a. Pump vacuum in the biphenyl ether system with liquid ring vacuum pump of

the vent system.

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b. Ensure that Biphenyl ether evaporator has been inventoried upto the

operating setpoint.

c. Open the inlet and outlet block valves of the HTM control valve for the HTM

evaporators and adjust the primary HTM flow through control valve.

d. Increase the temperature of biphenyl ether evaporator at the rate of

10/hr

e. When the temperature rising of reactor is too slow or not uniform, carry out

the venting of the low boilers.

f. When the biphenyl ether evaporator pressure reaches upto the target

temperature and pressure the temperature or pressure is auto-controlled.

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1.3.10-HTM system