ELINATING UNPLANNED FLARRING CO2 REMOVAL PLANT DUE TO VOLTAGE DIPS THROUGH ADITECH INNOVATION (ANTI DIPS TECHNOLOGY) ON VACUUM PUMP CONTROL PANEL AT CO2 REMOVAL PLANT PERTAMINA EP ZONE XYZ
Ratno Tri Prima Wahyudi1, Dwi Hardi Prasetyo Ananto2,
dan Aditya Bakti Priahutama3
1 Pertamina
EP Subang Field, Subang, Indonesia, ratno.wahyudi@pertamina.com,
dwi.ananto@pertamina.com, aditya.priahutama@pertamina.com.
ABSTRAK
Subang Field has several structures among them is the Big Bamboo
Structure (BBS) where the BBS structure is the backbone that contributes 40% of
the production of Subang field with a production of 1250 Bopd and 18 MMscfd.
Source power at SP BBS uses PLN capacity 725 KVA and backup uses DEG (Diesel
Engine Generator) Capacity 875 KVA. Obstacles to Unplanned Shutdown in the CO2
Plant Removal process (plant shutdown occurred from January 1, 2023 to August
2023) as many as 26 times with LPO 3,467 MMSCFD or equivalent to IDR
527,280,000.00 due to voltage dips in the PLN network.
Therefore, the Technology Modification of Starting Vacuum Pump CO2
Removal Using Inverter (Aditech method) was carried out in CO2 Removal SP.BBS
to solve the problem of unplanned shutdown in CO2 Removal SP BBS system..
From the results of this modification, in 2024
there were 41 incidents of voltage dips from PLN's Relay Network, but they did
not shut down the CO2 Removal plant, thus avoiding the LPO amounting to 5,477
MMSCFD or equivalent to IDR 831,480,000.00 and reducing emissions by 2,559 tons
of CO2 Eqv which should have arisen as a result of flaring during the CO2
Removal System Shutdown.
Keywords: PLN Voltage Dips, LPO from Flarring, Dealing with Dips, CO2 Removal Plant
1. 1. Background of the Problem
Associated Gas in SP.BBS comes
from LP Well of 3 mmscfd (High Impurities CO2, Low Pressure) so that it
requires a gas compressor and CO2 Removal Plant so that the gas can be sold to
the open access network. When the CO2 Removal is shutdown, the gas of 3 mmscfd
will be flared and there will be LPO gas sales of 0.8 mmscfd. The process
sequence of shutdown and running of the CO2 Removal Plant takes 4 hours.
The vacuum pump in the BBS CO2 Removal Plant functions to vacuum the PSA Package from 15 psig to -15 psig to the Vent Stack. If there is an anomaly in the vacuum pump, it will result in the entire CO2 Removal system being shut down and gas to flarring.
2. Problem Analysis
Like other plants at Pertamina EP which are close to the PLN high
voltage network, we use electricity power source from the PLN network because
more economic and more less maintenance. Most of Pertamina EP's plants are
located in areas on the edge of rice fields and forests, the potential for dips
is greater especially power source to SP BBS which is PLN Network has many
manuver because of same grid with many industry in Karawang Area.
According to the European standard EN 50160, a voltage dip is
defined as a sudden drop in the effective voltage value to a value between 90%
and 1% of the specified value, followed by a direct restoration of this
voltage. The duration of the voltage dip is between half a period (10 ms) and
one minute. If the effective value of the voltage does not fall below 90% of
the set value, this is considered normal operating status. If the voltage falls
below 1% of the set value, this is considered an interruption.
Figure 3. power failure explanation
Voltage dips
can lead to the failure of computer systems, PLC systems, relays, and frequency
converters. In critical processes, even a single voltage dip can result in high
costs, and continuous processes are particularly affected by this. And in this
case the process of starting the vacuum pump motor, it uses a soft starter
system where when there is a dip in the PLN power, the MCCB will trip if there
is no power coming in, even if only for a split second and this will cause the
vacuum pump to shut down so that the gas that should be able to flow to the vacuum
pump will be blocked and a high-high alarm will appear on the suction side of
the pump and the SDV will automatically open the pressurized gas to the flare
line to be burned.
Voltage Dips has recorded in the SP BBS more than 26 times a year with LPO gas flaring caused by dips which then result in plant shutdowns more thanof 3,867 MMSCFD. PT Pertamina EP Subang Field is committed to reducing flare gas throughout the Subang Field work area in line with ESDM Regulation Number 17 of 2021 concerning the Implementation of Flare Gas Management in Oil and Gas Business Activities.
3. DiscusionSolution Problem Solven
There are 3
alternative solutions being studied to overcome the problem of voltage dips at
SP BBS Subang Field. The 3 alternatives are using static UPS, DRUPS, and the
Aditech method.
Figure
4. Table comparison of 3 alternatives
Based on the
comparison of costs, time and operations, it was concluded that using the
Aditech method had the most positive results, so this alternative was chosen.
On the
selected solution, we designed the VSD installation as a replacement for the
soft starter by using a series that has a capacitor so that it can store
current to withstand motor torque when dips occur.
Figure
5. MCC CO2 Removal SP.BBS Electrical Circuit
4.
The following working
principle of the Aditech method
Design and
selection the VSD module installation as a replacement for the soft
starter in the SP BBS CO2 Removal system by using a series that has a DC capacitor
as DC Link Bus so that it can store current to maintain the voltage to the
electric motor vacuum pump when a power failure or voltage dips occur.
If the
inverter brakes the motor, the kinetic energy of mechanical load is converted
to electric energy to be transmitted into the inverter circuit. This
regenerative energy is often consumed in so-called braking resistors as heat.
An ACR (AC Reactor or Inverter ) is effectively used when the power
supply is unstabilized (excessive interphase voltage unbalance) or in DC link
bus operation (shared PN operation) requiring stable DC power. It is also used
for power supply matching and for correction of voltage waveform and input
power factor.
Figure 6. Voltage wave form correction when capacitor is applied
The inverter
recognizes a momentary power failure upon detecting the condition that DC link bus
voltage goes below the undervoltage level, while the inverter is running. If
the load of the motor is light and the duration of the momentary power failure
is extremely short, the voltage drop may not be great enough for a momentary
power failure to be recognized, and the motor may continue to run
uninterrupted. Upon recognizing a momentary power failure, the inverter enters
the restart mode (after a recovery from momentary power failure) and prepares
for restart. When power is restored, the inverter goes through an initial
charging stage and enters the ready-to-run state. When a momentary power
failure occurs, the power supply voltage for external circuits such as relay sequence
circuits may also drop so as to turn the run command OFF.
Figure 7. inverter working process when power failure
Based on the study of the Aditech methode, it was decided to
design and install an inverter with a type that has a DC capacitor with a
wiring diagram as below.
Figure
8. conncetion example residual current protection device
5.
Installation Process
And here is the flowchart for installing the ADITECH method:
Starting from
studying related to single line diagram SP BBS, wiring diagram MCC and CO2
Removal control panel unplanned shutdown simulation is done to find out the
main cause of CO2 Plant unplanned shutdown followed by designing the aditech
method then the procurement process. After the material arrives, the
installation and commissioning process, monitoring results and standardization
are continued.
Figure
9. Flowchart Modifikasi ADITECH
Figure
10. Before Intalation figure
11. After Instalation
6. Result
Figur 12.
Grafik Frekuensi shutdown CO2 Removal sebelum dan sesudah pemasangan ADITECH
From the results graph above, it can be seen that before the
ADITECH technology was installed, the CO2 Removal Plant shutdown always
occurred when there was a PLN voltage dip, but after the ADITECH technology was
installed, when the PLN voltage dip occurred, it would not cause the CO2
Removal system shutdown at SP BBS.
It can be concluded that since the installation of ADITECH technology on the CO2 Removal vacuum pump, the frequency of plant shutdowns due to PLN voltage dips can be eliminated.
Since Instalation in 2024 there were 41
incidents of voltage dips from PLN's Relay Network, but they did not shut down
the CO2 Removal plant, thus avoiding the LPO amounting to 5,477 MMSCFD or
equivalent to IDR 831,480,000.00 and reducing emissions by 2,559 tons of CO2
Eqv which should have arisen as a result of flaring during the CO2 Removal
System Shutdown.
7.
Thank you and Support
Thank you to Mr. Ndirga Andri Sisworo, Mr.
Emond Winarto, Mr. Eko Tri Wahyudi, for their support and direction so that
this journal and innovation can be completed and become an alternative solution
option for solving the PLN Dips problem at SP BBS in particular and hopefully
can be used elsewhere at PT Pertamina EP in general. Thank you to the entire
Subang Hebat Team for their cooperation in completing the Aditech innovation on
the vacuum pump control panel at the SP BBS CO2 Removal Plant.
8.
DAFTAR PUSTAKA
· International
Standard IEC 61000-4-30 : Testing and
measurement techniques – Power quality measurement methods.
· International
Standard IEC 60038 : IEC standard
voltages, defines a set of standard voltages for use in low voltage and high
voltage AC and DC electricity supply systems.
· International
IEEE Standard 1159-1995 : Recommended Practice for Monitoring
Electric Power Quality
· European
Standard EN 50160 – Voltage
Characteristics of Public Distribution Systems
· Ian K.P. Ross, MIEE, VOLTAGE SAGS AN EXPLANATION CAUSES, EFFECTS AND
CORRECTION, https://www.janitza.com/knowledge-database/voltage-dips-and-interruptions.html , 2023.
·
Fuji electric inverter
frenic installation dan manual shop.
·
https://www.ashleyedison.com/2021/12/30/top-5-solutions-to-solve-voltage-drops/
· Freeman Chiranga, Lesedi Masisi, Variable Speed Drive DC-Bus Voltage Dip Proofing, School of Electrical and Information Engineering, University of the Witwatersrand, Johannesburg, 2000.
9. 9. ABOUT THE AUTHOR
Ratno Tri Prima Wahyudi, born in Lumajang,
March 25, 1987. Educational background: He has taken Diploma 3 in Mechanical
Engineering at the Malang State Polytechnic, then continued bachelor degree in
the Department of Mechanical Engineering at Mercubuana University. Currently a
professional career as a Senior Supervisor of Production BBS & CCH at PT.
Pertamina EP Subang Field, Regional 2 Zone 7. Total experience of 16 years in
Oil & Gas Company.
Dwi Hardi Prasetyo Ananto, born in Ngawi on August 9, 1976. With a background in Field Mechanical Engineering from Akamigas Cepu and S1 Management, Experience working in the world of Oil and Gas mechanics since 1994 in Onshore and Offshore maintenance Gas Ccmpressor, Genset, Pump, Crane, Gas Turbine Generaor, Hottaping and other blogs. Oil and Gas Industry Mechanic.
Aditya Bakti, born in Magelang, October 29,
1988. Background of Strong Current Electrical Engineering Education, Diponegoro
University, Semarang. After being unfortunate in various work locations, PT
Pertamina EP is currently in the OSF Zone 7 engineering section of PT Pertamina
EP. Total experience 11 years in Oil & Gas Company.