Steam Temperature. HanPHI Catches at KNPC: Naphtha Unit. Early Warnings Generated by HanPHI

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1 HanPHI Catches at KNPC: Naphtha Unit Steam Temperature On December 10, 2013, the Naphtha unit health index dropped. The minimum tag was 17TI292, a tag measuring the IT steam tofrom unit 17 temperature. Plant KNPC System Naphtha HTU-17 Tag Name 17TI292 Description IP Steam to-from Unit Expected Value Operating Min Operating Max HanPHI generated an alarm for 17TI292 on December 10. Between March 29, 2013 and March 25, 2014,, the tag had shown a similar behavior three different times. Normally, the recycle compressor exhaust steam is at 150 psi and temperature is high compared to the 150-psi refinery header steam (IP). A de-super header is provided with the boiler feed water injection to reduce the high temperature to the refinery header temperature. There is a local TIC310 for reducing the temperature and was malfunctioning during these periods. The malfunction of the local TIC310 leads to the water hammering at the utility header. KNPC s DCS system did not have the capability to monitor this effect, so HanPHI gave the operators early warnings to act and prevent damage.

2 Vaporizer Bottom On February 10, 2014, the Naphtha unit health index dropped. The minimum tag was 17LI109, a tag measuring the vaporizer bottom. Plant KNPC System Naphtha HTU-17 Tag Name 17LI109 Description V-103 Vaporizer Bottom Expected Value 2.7 Operating Min Operating Max 2.7 HanPHI generated an alarm for 17LI109 on February 10. Between November 1, 2012 and March 25, 2014,, the tag had shown a similar behavior numerous times. The unit was under a start-up condition during the period. When the coker is heavy, it tends to collect liquid in the drum V-103. In normal operation, no liquid is present. When starting up, the reactor temperatures increase gradually and the liquid collection (heavier than the Naphtha range) and level increases. KNPC DCS alarm system is capable of observing this case, but HanPHI is capable of notifying the plant of an emergency situation due to an abnormal level build up in the V- 103 which leads to a reactor top flank leak if left unattended.

3 Inlet Temperature On November 19, 2013, the Naphtha unit health index dropped to 25.7%. The minimum tag affecting the overall health index was 17TI180, a tag measuring the sat feed E-104 inlet temperature. At the same time, the Reaction unit health index was 21.2% and the Stripper unit health index was 98.2%. Plant KNPC System Naphtha HTU-17 Tag Name 17TI180 Description Sat Feed E-104 Inlet Expected Value % Engineering Unit F Operating Min Operating Max Figure 1: Naphtha Unit Health Index This was not the first time the inlet temperature went outside of the operating range. From April 27, 2012 to February 4, 2014, the tag had shown a similar behavior five different times. Figure 2: Actual vs Expected Figure 3: Historical Trend Compressor Pressure On March 1, 2014, the Naphtha unit health index dropped to 74.99%. The minimum tag affecting the overall health index was 17PI820, a tag measuring the recycle gas pressure. At the same time, the Reaction unit health index was 68.4% and the Stripper unit health index was 98.6%. Figure 4: Naphtha Unit Health Index

4 Plant KNPC System Naphtha HTU-17 Tag Name 17PI182 Description RCY Gas Comp C-101 Suct Expected Value % Engineering Unit PSIG Operating Min Operating Max On March 4, 2014, the Naphtha unit health index was 76.67%, but by March 7, 2014, the Naphtha unit health index dropped to 46.99%. On March 7, 2014, the Reaction unit health index was 44.4% and the Stripper unit health index was 98.8%. Tag Name 17PI182 Description RCY Gas Comp C-101 Suct Expected Value Engineering Unit PSIG (March 4) (March 4) % (March 7) (March 7) 30.37% This was not the first time the pressure went outside of the operating range. From September 5, 2013 to March 28, 2014, the tag had shown a similar behavior six different times. Figure 5: Actual vs Expected Heat Rate Figure 6: Historical Trend On December 3, 2013, the Naphtha unit health index dropped to 30.2%. The minimum tag affecting the overall health index was 17TI303, a tag measuring the heater pass 2 outlet temperature. At the same time, the Reaction unit health index was % and the Stripper unit health index was 99.84%. Figure 7: Naphtha Unit Health Index Plant KNPC System Naphtha HTU-17 Tag Name 17TI303 Description H-101 HTR Pass 2 Outlet 0 Expected Value 774.3

5 0% Engineering Unit F Operating Min Operating Max On December 17, 2013, the Naphtha unit health index was 93.78%, and by December 31, 2013, the Naphtha unit health index was On December 31, 2013, the Reaction unit health index was 88.06% and the Stripper unit health index was 99.32%. Tag Name 17TI303 Description H-101 HTR Pass 2 Outlet Expected Value Engineering Unit F 0 (December 17) (March 4) 0% 0 (December 31) (December 31) 0% This was not the first time the temperature went outside of the operating range. From September 15, 2013 to April 14, 2014, the tag had shown a similar behavior four different times. Figure 8: Actual vs Expected Figure 9: Historical Trend Heater Pressure On December 28, 2013, the Naphtha unit health index dropped to 41.99%. The minimum tag affecting the overall health index was 17PI115, a tag measuring the heater convention pressure. At the same time, the Reaction unit health index was % and the Stripper unit health index was 98.67%. Figure 10: Naphtha Unit Health Index Plant KNPC System Naphtha HTU-17 Tag Name 17PI115 Description H-101 HTR Conv Section

6 1.021 Expected Value.1 0% Engineering Unit INH20 Operating Min Operating Max On January 18, 2014, the Naphtha unit health index was 42.88% and the Reaction unit health index was % and the Stripper unit health index was %. Tag Name 17PI115 Description H-101 HTR Conv Section Expected Value 0.1 Engineering Unit INH (January 18) (January 18) 4.54% This was not the first time the pressure went outside of the operating range. From November 2, 2012 to February 18, 2014, the tag had shown a similar behavior six different times. Figure 11: Actual vs Expected Figure 12: Historical Trend Vaporizer Pressure On November 26, 2013, the Naphtha unit health index dropped to %. The minimum tag affecting the overall health index was 17PC135_PV, a tag measuring the RX system pressure. At the same time, the Reaction unit health index was 8.488% and the Stripper unit health index was %. Figure 13: Naphtha Unit Health Index Plant KNPC System Naphtha HTU-17 Tag Name 17PC135_PV Description RX System Pressure

7 Expected Value % Engineering Unit PSIG Operating Min Operating Max On January 18, 2014, the Naphtha unit health index was %., and by February 1, 2014, the Naphtha unit health index decreased to %. On February 1, 2014, the Reaction unit health index was 8.452% and the Stripper unit health index was %. Tag Name 17PC135_PV Description RX System Pressure Expected Value Engineering Unit PSIG (January 18) (January 18) % (February 1) (February 1) 0% This was not the first time the pressure went outside of the operating range. From May 4, 2012 to April 24, 2014, the tag had shown a similar behavior five different times. Figure 14: Historical Trend Figure 15: Actual vs Expected

8 Main Steam Pressure On November 27, 2013, the Naphtha unit health index dropped to %. The minimum tag affecting the overall health index was 17PI255, a tag measuring the main steam pressure. At the same time, the Reaction unit health index was % and the Stripper unit health index was %. Plant KNPC System Naphtha HTU-17 Tag Name 17PI255 Description MP Steam Tonaph HTU Expected Value % Engineering Unit PSIG Operating Min Operating Max Figure 16: Naphtha Unit Health Index On January 29, 2014, the Naphtha unit health index was %., and by February 8, 2014, the Naphtha unit health index was %. On February 8, 2014, the Reaction unit health index was % and the Stripper unit health index was 99.7%. On March 22, 2014, the Naphtha unit health index had dropped again to 27.38%. Tag Name 17PI255 Description MP Steam Tonaph HTU-17 Expected Value Engineering Unit PSIG (January 29) (January 29) % (February 8) (February 8) % (March 22) (March 22) 3.706% This was not the first time the pressure went outside of the operating range. From December 7, 2012 to March 29, 2014, the tag had shown a similar behavior seven different times. Figure 17: Actual vs Expected Figure 18: Historical Trend

9 HanPHI Catches at KNPC: Reaction Unit STR Feed Due to an IP-21 network communication problem, data for the tag 17FC132_PV was not retrieved. On January 22, 2014, there was a refinery power failure, which led to data being unavailable from January No Data No Data Power Failure On Febuary 11, 2014, the same tag dropped to , but the tag low range is 0. The engineers determined that it was a result of the coker unit problem (compressor trip) that affected the coker feed. Once the coker feed was normalized, the situation corrected itself. O2 Analyzer Between December 28 December 29, 2013, 17AI101 displayed different behavior. The tag is in the recycle gas heater stack and is the O2 analyzer. This resulted from an excess analyzer as 17AI101 was calibrated and the stack damper adjusted during an energy audit period. Heater Conv Pressure

10 17PI115, the pressure of the heater conv section, fluctuated for some. It reached a maximum of IN H2O. On November 18, 2013, there was a recycle gas compressor governor problem and the heater tripped. The compressor problem was fixed, but on December 28, 2013 and January 14, 2014, the air registers and dampers were adjusted during an energy audit that resulted in 17PI115 fluctuations. On January 18, 2014, the heater conv section pressure increased to IN H2O. Reactor Temperature 17TI129, the reactor temperature, fluctuated in February The temperature dropped to F, while the expected temperature was 608 F. During the period, the ARDS feed to U-17 was stopped as a result of an ARDS upset. The feed from Crude U-11 was used. Since the low temperature was for a short duration, it did not impact the product quality.

11 RX Pressure System On February 1, 2014, 17PC135_PV fluctuated due to an upset in the plant. The tag is the RX system pressure and has a max value of PSIG and a min value of PSIG. During the period, the ARDS feed to U-17 was stopped as a result of an ARDS upset. The feed from Crude U-11 was used. Since this was for a short duration, it did not impact the product quality. Gas Component Pressure On February 1, 2014, 17PI182 fluctuated due to an upset in the plant. The tag is the pressure of a gas componenet and has a max value of PSIG and a min value of PSIG. During the period, the ARDS feed to U-17 was stopped as a result of an ARDS upset. The feed from Crude U-11 was used. Since this was for a short duration, it did not impact the product quality.

12 Vaporizer Inlet Temperature On February 1, 2014, 17TI161, the vaporizer inlet temperature dropped suddenly. The normal temperature is between F, but it dropped to F. This was a result of the coker system. The coker feed fluctuated and dropped below normal, which result in the vaporizer inlet temperature decreasing. When the coker feed normalized, the vaporizer temperature increased. Saturated Feed Flow On March 4, 2014, 17FC102_PV, the saturated feed flow, suddenly increased to , while the exepected value was This resulted from a Coker U-20 upset that increased the feed rate from the ARD (saturated feed). Steam Pressure On January 29, 2014, 17PI255, the steam pressure to Naptha HTU-17, fluctuated. The pressure initially increased to 475 and suddently decreased to 405. It was determined that there was a utilities section problem.

13 HanPHI Catches at KNPC: Stripper Section Overhead Temperature System On December 27, 2013, 17TI214, the overhead temperature system, suddenly increased to 257 F. The stripper top temperature depends on the reflux flow rate. The reflext flow rate depends on the reflux drum level, which depends on the stupper bottom temperature. The overall feed quality changes the top temperature of the stripper. Once the feed quality normalized, the normal top temperature normalized. Coker Feed On January 22, 2014, 17TC192_PV dropped suddenly as a result of a power failure. The reactor- 102 outlet stream is the heating medium for the stripper bottom. During a power failure, the unit feed is cut off and no heating medium is available, so the temperature dropped suddenly. On February 10, 2014, the tag temperature 17TC192_PV dropped again to F. In addition, 17PC148_PV pressure dropped suddenly. The max value is PSIG and the min value is PSIG. Both drops were a result of a coker unit compressor trip. The coker feed was not available so the R-102 outlet temperature dropped. As a result of the upset, the product was offspec.

14 When the coker feed normalized, the reactor conditions stabilized and stripper bottom temperature increased and returned to normal. Similarly, the pressure (top OVHD pressure) increased and returned back to normal.