Risk Assessment and Safety Analysis on Power Generation Boiler At PT.Petrokimia Gresik,Indonesia

Transcription

1 Risk Assessment and Safety Analysis on Power Generation Boiler At PT.Petrokimia Gresik,Indonesia Ronny D. Noriyati 1, Septian H. Pradana 2, Silvana R.Dacosta 3, Ali Musyafa 4, Adi Suprijanto 5 1,2,3,4, Jurusan Teknik Fisika, 5 Jurusan Teknik Elektro, Fakultas Teknologi Industri, Institut Teknologi Sepuluh Nopember (ITS), Jl. Arief Rahman Hakim, Surabaya Indonesia onny@ep.its.ac.id, septianharipradana@gmail.com, sdacosta@pertamina.com, musyafa@ep.its.ac.id, adisup@ee.its.ac.id. Abstract Level of safety and risk petrochemical process industry must be guaranteed. Instrument as a safeguard should be able to guide and provide protection against worker safety, environmental and corporate assets. So that the necessary hazard studies and risk management assessment of the plant that has been operating in a relatively long period. PKG industry is one of the largest fertilizer producer in Indonesia supported the important equipment and need serious attention. Boilers are at risk and danger equipment relatively high. So it is necessary to study. Danger level measurements performed with HAZOP studies with determination nodes consisting of; economizer, steam drum, superheated, and burner system which is the main constituent components of the boiler By evaluating the systems supporting documents consisting of Process Flow Diagram (PFD), P & ID and historical maintenance data for the period scheduling. That components having the highest risk of harm is Pressure Indicator Inlet steam drum, Temperature Indicator (TI-6211) and Temperature Superheated Outlet Indicator (IT-6214), with the level of risk is worth 5 (extreme) refers to the standard AS / NZS 4360: Each of the other nodes in the boiler has a SIL 1, with a risk reduction factor = 50 for economizer, steam drums = 39.1 and superheated and burner system = 30. Based on the value of the boiler system has a relatively low reliability level indication. Decrease risk and increase system reliability is done with care and instrument calibration routine, the increase of redundant instruments (sensors, transmitters, controllers and final control elements) should be maintained strictly. Potential hazards occur on all nodes in the form of fire. So that emergency response plans (ERP) and management measures need to be updated. Key word Risk Management, boilers, HAZOP, emergency response plan, SIL I. INTRODUCTION Potential occupational accidents have such levels of workplace accidents mild to severe accidents. Potential work accidents can happen as blast boiler system. Equipment in the plant can cause unsafe conditions for workers and the probability of danger arising resulting in disability and even death. The failure of the system that occurs affects the inconvenience operational equipment operators, the environment and assets. Damage that occurs in one component will cause greater damage to the entire plant. Damage to plant danger workers and communities around the plant. Security and safety of operating the plant can be met if the existing system in the plant is functioning in accordance with the standards and specifications that have been determined (AZ/NZS, 1999). Boiler unit (B-6203) is one of the important equipment in petrochemical production process. Functioning boiler unit generates heat system with mecanism changing production material from the liquid phase to vapor through the heating process. Boiler system failure caused not only by the process that occurs in the boiler system, but also due to instrument failure. The failure of the boiler unit will hamper the sustainability of the process production resulting in financial losses, accidents and safety of the operator. If the failure to achieve such high level of dangerous fires, the losses suffered by the company is very large, including the reputation, (Depat.Mnj. Risiko 2014). With this research activity, then any potential hazards that would arise detection can be anticipated as early as possible and, from this study are expected to be given recommendations regarding the proper maintenance of the system so that the system components to function properly. In the boiler unit identified operational process systematically, identify the device whatever, and distorted, what encourages potential hazards and accidents. Further analysis through the development of risk management and emergency response plan, emergency respond in case of danger and accidents in equipment and company plant. Unit B-6203 boiler used to produce steam which serves for the generation of electricity in the plant III PT. Petro Kimia Gresik. Part boilers include: economizer, boiler systems equipment used to preheat boiler feed water from Water Pump before entering the combustion cycle. Steam drum, the equipment in the boiler system that serves to place the vapor

2 phase separation with water. Down corner, the pipe from the steam drum is used to drain water to the water wall., the wall in the form of vertical pipes surrounding the furnace (combustion chamber) as a water heating boiler. Superheated, change the saturated steam into hot steam up. Furnace, the room is used to heat the boiler pipes (water wall) so that the water will turn into steam. Boiler used is a boiler with a boiler-type tubers corner. Here is the specification of boiler B in accordance with that shown in Table 1. Tabel 1. Spesifikasi Boiler B-6203 Tag Number Specification B-6203 Capacity Design pressure : 52 MT/h : 35 Kg/cm 2 Design Temperature : 408 o C Fuel : Heavy Oil Type : Steam Atomizing Drum : ASTM SA515 Gr60 Tube : ASTM SA 192 Superheater : ASTM SA 192 Economizer : ASTM SA 192 (source: Dokumen PT Petrokimia Gresik, Depat.Mnj. Risiko 2014). II. MATERIAL AND METHODS Steps being taken in the study and operational hazards (HAZOP) and risk management are as follows; A. Procces Study Research activities began with the study of the production of steam which is then used for the generation of electricity in the plant III PT.Petrokimia Gresik. Specifically conducted a study on the characteristics of the boiler is also used to support the activities of the unit at the factory Sulfur III, the activities undertaken to get understanding associated with next research. The data collection of process daily for one month duration full range of data each time kidnapping one hour. (Arnljot, H. d. 1994). B. Data Accusation Data were sampled in this study include the following documents flow sheet of the boiler unit (B-6203) Sulfuric Acid Plant III, PT Petrokimia Gresik. These documents include process flow diagram (PFD), List of instruments, maintenance of data or data playing time to failure of each component contained in the steam boiler and process data on any boiler components are fully operational throughout the day. These data were taken in the duration of one month of the date of 1 to 31 March The data sampling every hour per 24 hours/day. Data are then used in the study of risk assessment, risk analysis on each component of the boiler unit. The method used in hazard identification and analysis method Hazard Operability Analysis (HAZOP). The stages of hazard identification using HAZOP method as complete. Determine the node / point of study based on data P & ID. In this study, the node is determined based on the major components that make up the boiler system, the economizer, steam drum, superheated, and consistent burner. At each node specified any components contained at that point, which affects the quality of the process from input to output. For each loop starts from the flow transmitters, temperature transmitters, pressure transmitters, control until the safety valve and supporting components that support the process. Determination of the component is based on the components installed on the P & ID and DCS screens boiler. Determine guideword using process data taken on each of the components for a month with a control chart, then look at the trend data that has been constructed from the graph to determine the deviation of the process variable. Control charts are built with the following equation; UCL = x + A 3 s (1) CL = x (2) LCL = x - A 3 s (3)

3 L is a coefficient that indicates the level of trust units. Analyze the causes of the deviation that has previously been determined and the consequences arising and what safeguards are owned by the boiler unit in a single node. (Dhillon, B. 2005). C. Risk Estimation Risk estimation is done by analyzing the two components of the probability and consistent, namely: Likelihood is the probability of a risk that can occur in a component in a given period. Likelihood estimation is calculated by using the data report diaries control room and the data of each component failure at a certain period, nex find the value of Mean Time To Failure (MTTF), the average time that a component failure. Likelihood value obtained from the comparison between the amount of the daily operations of the MTTF value overall production period, in one day running the production company for 24 hours. Furthermore, the likelihood is determined level. Overall operating time period used for 7 years, so the likelihood calculation follows the following equation: Likelihood = / MTTF (4) As for the components that are not available in the data maintenance, MTTF value is calculated from the data failure rate contained in the database Offshore Reliability Data. The equation used is as following, (Oreda 2002). MTTF = 1/ failure rate (λ) (5), are determined based on the reading of the transmitter and indicator deviation from the average value observed at the level of control achieved by the data limit. Overview associated with the level of damage to components, effects on humans and the level of costs incurred due to the danger posed with lost due loose cost of production due to the process. Referenced standard is the standard Australian / New Zealand, (AS / NZS 4360: 2004). Risk Analysis Analysis of the risk carried out by combining the likelihood and that have been obtained in the estimation stage. The combination is obtained by using a risk matrix which refers to the standard AS / NZS 4360: 2004 standards adequate for PKG shown in Table 2. Table 2. Risk Matrix Standard AS/NZS 4360:2004 Likelihood Insignificant Minor Moderate Major Catastrophic A (Almost certain) H H E E E B (Likely) M H H E E C (Moderate) L M H E E D (Unlikely) L L M H E E (Rare) L L M H H D. Safety Integrity Level (SIL) Analysis of safety integrity level is done to look at a system lies in a certain security level. SIL is determined by finding the average PFD value adjusted by the SIL table shown in Table 3.(Ebeling, C. E. 1997). Tabel 3. Table safety integrity level Safety Integrity Level Probability of Failure on Demand Risk Reduction Factor 4 0,0001 0, ,001 0, ,01 0, ,1 0,

4 E. Analysis Emergency Response Plan (ERP) ERP analysis was done by determining the most likely risks and the most profound impact on the system. The most influential risk is determined based on the results of analysis on HAZOP table. Furthermore, identified safeguards and evacuation measures as would be done in case of danger, how the response and the responsibility of the relevant divisions are directly affected (Occupational Safety and Health. 2004). III. ANALYSIS AND DISCUSSION Limits used in the study of risk analysis, systems division into four nodes are analyzed by dividing into; economizer, steam drum, superheated and burner systems Economizer Economizer supports preheating (pre heat) boiler feed water before it goes into the steam drum. There are 5 components contained in the economizer instrumentation that flow valve 6212 (FV-6212), flow transmitter 6212 (FT-6212), the level indicator 6212 (LI-6212), the level transmitter 6212 (LT-6212), and pressure indicators 6213 (PI-6213). In the FV-6212 components are not logged data sheet, because the flow that flows into the economizer is a free variable that follows the state of the process is shown in Figure 1. Figure 1. Paping and Iinstrument Drowing of Economizer Guide Word and the deviation are shown in Table 6. Figure 2. Control chart x -s for PI-6213 From Figure 2 that the number of data obtained from the reading of the indicator is above the average value whose value is 9.48 psig, with an average deviation of So your word used high with high pressure deviation. In addition to the data used to determine your word can also be used to determine the, from Figure 2, the data reaches the boundary line, and consequently worth 2. Guide economizer word shown in Table 4. Table 4. Guide Word and Deviaton on Economizer No. Guide word Deviation 1 Flow Transmitter (FT-6212) Less Less Flow More More Flow 2 Level Transmitter (LT-6211) Less Less level 3 Pressure Indicator (PI-6213) High High Pressure Likelihood Estimation Likelihood estimation is done based on data taken daily report [2]. Likelihood is determined by the equation 4 is shown Table 5. Table 5. Likelihood criterion on Economizer node Tag Number MTTF Likelihood Likelihood criterion FT ,87 E (1) LT ,94 C (3) PI ,50 C (3)

5 3.2. Steam Drum There are four components in the steam drum instruments that help process therein that the level transmitter 6212 (LT- 6212), flow transmitter 6212 (FT-6212), 6213 pressure indicator (PI-6213), and 6220 pressure indicator (PI-6220) as shown Figure 3. Figure 3. Paping and Instrument Drowing of Steam Drum Guide Word and the deviation are shown in Table 6. Tabel 6. Guide Word on Steam Drum No. Guide word Deviation 1 Flow Transmitter (FT-6212) Less Less Flow 2 LevelTransmitter (LT-6212) Less Less level 3 Pressure Indicator (PI-6220) Low Low Pressure 4 Pressure Indicator (PI-6213) High HighPressure Estimasi Likelihood shown Table 7. Table 7. Likelihood criterion on Economizer node Tag Number MTTF Likelihood Likelihood criterion FT ,87 E (1) LT ,50 C (3) PI ,35 E (1) PI ,50 C (3) 3.3. Superheater There are four components of instrumentation that work on the superheated control systems that flow transmitter 6213 (FT-6213), a pressure indicating controller 6221 (PIC-6221), temperature indicator 6211 (IT-6211), and a temperature indicator 6214 (TI-6214) shown in Figure 4. Figure 4. Paping and Instrument Drowing of Superheater Guide Word and the deviation are shown in Table 8. Table 8. Guide Word on Superheater No. Guide word Deviation 1 Flow Transmitter (FT-6213) Less Less Flow 2 Pressure Indicating Controller (PIC-6221) High High Pressure 3 Temperature Indicator (TI-6211) Low Low Temperature High High Temperature 4 Temperature Indicator (TI-6214) Low Low Temperature High High Temperature

6 Estimasi Likelihood shown on Table 9. Table 9. Likelihood Criteria on superheated node Tag MTTF Likelihood Likelihood criterion FT ,94 E (1) PIC ,46 E (1) TI ,35 E (1) TI ,54 E (1) 3.4. Burner System Burner serves to provide heating to a high temperature in the furnace (furnace). There are several components that are contained in the burner, but the components contained in the log sheets are only 4 are flow indicator (FI-6217), indicating flow controller (FIC-6219A), pressure indicator (PI-6217), and temperature indicator (TI 6217) shown in Figure 5. Figure 5. Paping and Iinstrument Drowing of Burner system Guide Word and the deviation are shown in Table 10. Tabel 10. Guideword on Burner No. Guide word Deviation 1 Flow Indicator (FI-6217) Less Less Flow 2 Flow Indicating Controller (FIC-6219A) Less Less Flow More More Flow 3 Pressure Indicator (PI-6217) High High Pressure 4 Temperature Indicator (TI-6217) As Well As As Well As Temperature Likelihood estimation shown on Table 11. Analsis of Risk Matrix Table 11. Likelihood criterion on Burner node Tag MTTF Likelihood Likelihood criterion FT ,99 E (1) FIC-6219 A ,99 E (1) PI ,56 1,21 E (1) TI ,52 0,39 E (1) Economizer shown in Table 12. Table 12. Risk Matrix on Economizer base Plant Standard Likelihood class C1 Componen t class B2 class B3 class A4 1 (Brand New/Excellences). L (2. L (1) 2. (Very good/good Serviceable) 3. (Acceptable/Barely Acceptable). L (1).. M (1). 4. (Below standard/poor) 5. (Bade or Unusable) class A & L5

7 Steam Drum shown on Table 13. Likelihood Table 13. Risk Matrix on Steam Drum base Plant Standard Compone Componen class C1 nt class class B3 t class A4 class A & L5 B2 1 (Brand New/Excellences). L (2. L (1). M(1). 2. (Very good/good Serviceable) 3. (Acceptable/Barely Acceptable). L (1).. M(1). 4. (Below standard/poor) 5. (Bade or Unusable) Superheater shown on Table 14. Table 14. Risk Matrix on Superheater base Plant Standard Likelihood class C1 class B2 class B3 class A4 class A & L5 1 (Brand New/Excellences). (1).. (1). L (1). M (4). 2. (Very good/good Serviceable) 3. (Acceptable/Barely Acceptable) 4. (Below standard/poor) 5. (Bade or Unusable) Burner System is shown in Table 15. Table 15. Risk matrix on Burner System base plant standard Likelihood class C1 class B2 class B3 class A4 1 (Brand New/Excellences). (4).. L (1). 2. (Very good/good Serviceable) 3. (Acceptable/Barely Acceptable) 4. (Below standard/poor) 5. (Bade or Unusable) class A & L5 Safety Integrity Level (SIL) Based on data from failures that occur in each of the components in the boiler, it can be determined Safety Integrity Level (SIL) to determine the level of reliability of a system. In addition, to determine how the Probability of Failure on Demand (PFD) system that is currently installed. Value test interval used was two months, because based on historical data; the most frequent interval test performed two months. From the table it can be seen that the node economizer has SIL criteria 1, it indicates that the reliability of the system is still low. There may be a danger is still quite large. Value Risk Reduction Factor (RRF) is worth 50 shows that the rate of decrease in the risk is low. This is due to the performance test is rarely done on each of the components in the node instrumentation economizer. The greater the chance of failure is shown in Table 16. Table 16. SIL on node economizer Failure rate (λ S ) Test Interval hour PFD PVD avg. SIL Risk Reduction Factor Sensor 2.46 x x x Transmitter 1.52 x x 10-2 Final element control 9.87 x x 10-3 From the above table it can be seen that the steam drum node has a SIL 1 PFD average value of Risk reduction resulting value is 39.1 which indicate that the steam drum node failure occurs more potential than node economizer. To increase the value of SIL can be done by performing a test interval for each component 1 month is shown Table 17.

8 Table 17. SIL on steam drum node Failure rate (λ S ) Test Interval hour PFD PVD avg. SIL Risk Reduction Factor Sensor 5.75 x x x Transmitter 1.98 x x 10-3 Final element control 9.87 x x 10-3 Superheated node has criteria with SIL 1 PFD average worth Risk reduction is 30 shown enormous potential hazards on superheated nodes shown in Table 18. Table 18. SIL on superheated node Failure rate (λ S ) Test Interval hour PFD PVD avg. SIL Risk Reduction Factor Sensor 4.59 x x x Transmitter 3.16 x x 10-2 Final element control 9.87 x x 10-3 Node of burner has SIL 1 RRF value of 30, it indicates that a very large potential hazard considering burners operate at high temperatures, so one way to improve the reliability of the system is installing redundant on each component, or by increasing the interval test 1 month shown in Table 19. Table 19. SIL on Burner system node Failure rate (λ S ) Test Interval hour PFD PVD avg. SIL Risk Reduction Factor Sensor 4.59 x x x Transmitter 3.16 x x 10-2 Final element control 9.87 x x 10-3 Analysis of Emergency Response Plan is shown in Figure 6. Scene fires,,explosion,leakage The control of the danger level I Investigation, Evaluaton and Recomendation Control of the early Succed No Succed Control of continued Contributed to the people or require contributiod outsiders Rehabilytation and Contruction Succed No No The control of the danger level 1 fair to succed Reported and actioned further as industrial accidents The control of the danger Level II Status safe No Contributed to the people or require contributiod outsiders Figure 6. Flow Genesis Prevention State of Emergency IV. CONCLUSION s with high risk in the fourth node occur in the boiler steam drum inlet pressure indicator, temperature indicator (TI-6211) and the superheated outlet temperature indicator (TI-6214). Both components have a likelihood criterion E or 1, which means less than 2 times in 5 years and the consequences criterion 5, so the risk is worth Extreme Risk. To decrease this risk, can be done by performing routine maintenance, routine calibration transmitter and the addition of redundant transmitter, so the reliability of the system increases and the potential hazards can be reduced. The danger with the greatest risk to the boiler is fire. Therefore it needs to make emergency response plan or procedures for handling emergency fire hazard when it occurs in the boiler, includes the responsibility of each division, preventive measures, and measures taken. Based SIL analysis done, all the nodes in the boiler has SIL criteria 1, with a risk reduction factor ranging between which indicates that the reliability of the system is still low.

9 References [1] Arnljot, H. d , System Reliability Theory. The Norwegian Institute of Technology: John Wiley & Sons Inc. [2] Australian Standard/ New Zealand Standard 4360: Risk Management. Australian Standard. [3] Depat. Manajemen Risiko Kriteria Profil Risiko Pabrik III Gresik: Dep. Produksi III dan Dep. Pemeliharaan III PT. Petrokimia Gresik [4] Dhillon, B , Reliability, Quality and Safety for Engineers. USA: CRC Press. [5] Ebeling, C. E , An Introduction to Reliability and Maintainability Engineering. Singapore: The McGraw HillCompanies. [6] Elliott Company , Multi-Stage Centrifugal Compressors, Reliably serving the energy industries, Ebara Group 901 North Fourth Street Jeannette, PA , USA [7] Musyafa, A. et al , Risk Management and Safety System Assessment from Power Plant Steam Boiler in Power Systems Unit 5, Paiton -Indonesia. Australian journal of Basic and Applied Science (AJBAS), (ISSN: Published Sept [8] Musyafa, A. et al , Risk Management Using HAZOP Study Method Base Fault Tree Analysis on Emergency Shutdown System-Vacuum Distillation Unit, PT.PQR, Dumai, Indonesia, Asian Transactions on Engineering (ATE ISSN: ) Volume 03 Issue 05. [9] Musyafa, A. et al , Reliability and Maintainability Assessment of the Steam Turbine Instrumentation System for optimization Operational Availability System at Fertilizer Plant Australian journal of Basic and Applied Science (AJBAS), ISSN: Published August & Journal home page: [10] Montgomery, Douglas C.1999., Introduction to Statistical Quality Control 6 th Edition. United States of America. [11] Occupational Safety and Health Principal Emergency Response and Preparednes. U.S. Department of Labor. [12] Oreda Pasticipants Offshore Reliability Data. SINTEF Industrial Management [13] Sudarta , Evaluasi Reliability Pada Sistem Crusher Untuk Memperbaiki Kinerja Maintenance Di PT. Semen Gresik. [14] SINTEF , Industrial Management. Offshore Reliability Data Handbook 4 th Edition. OREDA Participants,2000 [15] Unido , Compressor Air System, Unido Patner and prosperity UNEP, (January, ), Compressors and Compresssed Air System, Energy Efficiency Guide for Industry in Asia