AD.15.03.02 Extreme Sampling: Flare Gas Hans-Peter Visser - PowerPoint PPT Presentation

AD.15.03.02 Extreme Sampling: Flare Gas Hans-Peter Visser Analytical Solutions and Products BV (ASaP) Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Content  Problems with current installation, effects and root cause.  Design criteria.  Design considerations.  Tests and field results. Slide 2 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Problems with new flare gas installation • Problems direct after start-up; – Plugging of narrow bore sample paths. – Severe fouling of wetted parts in analyzer installation. Slide 3 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Effects • Probe – Green crystals found. • Sample Conditioning System – Green/gray deposits on filters. • Analyzer – Particles in GC valves. Slide 4 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Root cause QT • Undersized process seal drums Slide 5 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

“Forgotten” first step 1. REASON AND PURPOSE OF MEASUREMENT Reason of measurement Yes/No Purpose of measurement Yes/No Criticality analyser Yes/No client (external/internal) / Trending / Safety / legalisation / monitoring / Process / product quality / control / Environment / energy efficiency / alarm / Quality / environmental / trip / Not critical / safety / management / Safety Integrety Level N/A process reliability / REMARKS: • Cycle time existing GC: 4 minutes. Slide 6 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Analytical requirements and existing installation Slide 7 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Requirements in a nutshell • Eliminate fouling and plugging. – Increase total system reliability. – Reduce maintenance. • Proper sampling. – Even at upset conditions with process velocity up to 100 m/s. – Lower water content/ water dewpoint without condensing hydrocarbons. Slide 8 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Conceptual thoughts • A combination of applied fluid dynamics and existing sampling techniques Slide 9 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Process conditions (worst case) ID Item Description Symbol Value Unit Remarks Reference 20 Pressue P p 0.076 BarG 21 Temperature T p 60 °C 22 Reference Pressure P ref 1.01325 BarG 23 Reference Temperature T ref 15 °C 24 Mol Weight Mw 25.85 kg/kmol Process Data kg/m 3 r Pp&Tp 25 Density @ Process P & T 1.009 kg/m 3 r Pref&Tref 26 Density @ Reference P & T 1.098 h 27 Dynamic viscosity 0.0000137 Pa.s @ Tprocess m 3 /hour f vol 28 Flow 61.51 29 Velocity V process 97 m/s 30 Reynolds Number Re process 6,418,316  x i ] 31 Composition See Tap " Input " @ BarG /  C f v, Fast Loop 32 Given/required Fast Loop Flow 4.59 l/min 0.076 60 • Extreme fluid velocity and Reynolds Number Slide 10 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Flow separation Slide 11 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Fluid dynamics Probe entrance • Supercritical Reynolds number (6.7 x 10 5 ) • Project case Re 6.4 x 10 6 Slide 12 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Stokes Law V F 18 ∗ h ∗ V f D H = r P − r F ∗ g V P Hence: D H : µm ; Liquid droplet or particle larger than D H will fall out. h : Pa.s ; Dynamic viscosity. V f : m/s ; Fluid velocity. r P : kg/m3 ; Density particle and/or droplet. r F : kg/m3 ; Density fluid. g : m/s2 ; Gravitational constant Slide 13 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Inclined orientation V V = V F ∗ SINα V F V v  18 ∗ h ∗ V f ∗ SIN  V h D H = V P r P − r F ∗ g Hence: V f : m/s ; Fluid velocity. V v : m/s ; Fluid velocity vertically. V h : m/s ; Fluid velocity horizontally.  :  ; Angle probe Slide 14 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Gravity separation ID Item Description Symbol Value Unit Remarks Reference 60 Fall-back tube OD OD FBT 1.05 Inch 3/4" Nominal Bore 61 Tube wall thickness TWT FBT 0.083 Inch Sch 10 62 Fall-back tube factor 20 Min.16xID or 400 mm 2 Stokes Law Falling Section 63 Total length fall-back tube L FBT 449.07 mm  64 Probe angle FBT angle 60 Falling from top downwards 65 Volume wetted parts Vol FBT 0.1778 L 66 Velocity V FBT 0.19 m/s 67 Reynolds Number Re FBT 320 1: page 81, (Table II.2) 68 Flow type Laminar 69 Pressure drop dP FBT 0.08 Pa Darcy equation 70 Lag time @ process conditions LT FBT 2.32 s 71 Lag time @ reference conditions LT FBT,ref 2.13 s kg/m 3 r el 72 Density entrained liquid 998 Water "particles" µ m 73 Particle seperation D H 49 Particles smaller than D H will pass r el kg/m 3 72 Density entrained liquid 2170 Salt particles µ m D H 73 Particle seperation 33 Particles smaller than D H will pass r el kg/m 3 72 Density entrained liquid 1800 Sulphur particles µ m D H 73 Particle seperation 37 Particles smaller than D H will pass Slide 15 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Self draining Slide 16 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Pressure drop and lag time ID Item Description Symbol Value Unit Remarks Reference 40 Insertion depth in process line Ins probe 100 mm 10.94% of ID main line 41 Probe diameter OD probe 1.05 Inch 3/4" NB 42 Schedule TKN probe 0.219 Inch Sch 160 43 Total length L probe 276.60 mm  44 Probe angle Pr angle 60 Falling from top downwards Probe 45 Volume wetted parts V w p,pr 0.052 L 46 Velocity V probe 0.40 m/s 47 Reynolds Number Re probe 462 1: page 81, (Table II.2) 48 Flow type Laminar 49 Pressure drop dP probe 0.20 Pa Darcy equation @ BarG /  C 50 Lag time @ process conditions LT probe 0.69 s 0.076 60 @ BarG /  C 51 Lag time @ reference conditions LT probe,ref 0.63 s 1.01325 15 Slide 17 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Design flare gas probe Slide 18 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

CFD Analysis by VSL Dutch Metrology Institute Probe entrance P= 108,000 Pa Reduced pressure; suction effect Slide 19 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Sample extraction Slide 20 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Proof of principle 1 Slide 21 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Proof of principle 2 Slide 22 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016

Mission accomplished Quote: “I forgot to specify. Obviously I meant filters clean in presence of several upsets. We had 3 upsets and several small discharges since the installation .” unquote. Slide 23 Analytical Solutions by the Sea The 61 st Annual Symposium of the Analysis Division Galveston Island Convention Center, Galveston, Texas, USA; 24 th – 28 th April 2016