A viability and environmental analysis of E-Roomie (now Room-Me), an online platform for smart real estate matchingFull description
Full description
MTE 3109
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Version 2.2: July 2012 ISBN: 978-9080179301 New Aesthetic New Anxieties is the result of a five day Book Sprint organized by Michelle Kasprzak and led by Adam Hyde at V2_ from June 17–21, 2012. A...
Descripción: New york new york big band not sinatra key
Frank Sinatras New York New YorkDescripción completa
New york new york big band not sinatra key
Descripción: Sheet Music (PDF)
Descripción: frank sinatra
New York, New York lead sheet music, Frank Sinatra arrangement
for choir
Flare Systems
Typical Relief System Vent Header
R.V.
RE/U&O Flares-2
Purpose of Flare
Define Loadings to be Handled –
–
–
Calculate loadings for all contingencies Geographic location of each source Calculate maximum load (power failure,fire case) • Fire case limited to a ground area of 230 - 460 square meters • Calculate maximum back pressure
Gas Composition Flow Rate Gas Pressure Available Initial Investment Operating Costs Gas Temperature Energy Availability Environmental Requirements Safety Requirements Social Requirements
Main Flare Standards and Recommended Practices
API RP 520: Part I – Sizing Selection and Installation of Pressure-Relieving Devices in Refineries – Part I – Sizing and Selection API RP 520: Part II – Sizing Selection and Installation of Pressure-Relieving Devices in Refineries – Part II – API RP 521: Guide for Pressure-Relieving and Depressurizing Systems API Standard 537: First Edition September 2003: Flare Details for General Refinery and Petrochemical Services RE/U&O Flares-5
US EPA Requirements – 40CFR60.18
Sizing must also comply with Federal Register (40 CFR 60.18) for maximum velocity of steam-assisted, elevated flares: Net Heating Value of Vent Stream Bv (Btu/scf) 300 300-1000 > 1000
It is standard practice to size the flare so that the design velocity of flow rate Qtot, is 80 percent of Vmax: Dmin (in) = 12*[((4/PI)(Qtot/60sec/min))/(0.8*Vmax)]^0.5 Dmin (in) = 1.95 * (Qtot/Vmax)^0.5 Where: Qtot = Q + F (measured at stream temperature and pressure) Dmin should be rounded up to the next largest available commercial size Btu/scf * 0.0373 = MJ/scm and ft/sec * 0.305 = m/s
Auxiliary Fuel Requirement
Amount of fuel required (F) is calculated based on maintaining the vent gas stream net heating value at the minimum of 300 Btu/scf (11.2 MJ/SCF) required as described in the United States Federal Register: (Q * Bv) + (F * Bf) = (Q + F)* (300 Btu/scf) Where: — Q = vent stream flow rate, scfm — Bv = Btu/scf of the vent stream — Bf = Btu/scf of the fuel stream Therefore, F (scfm) = Q * (300-Bv)/(Bf-300) The annual auxiliary fuel requirement (Fa) is: Fa (Msfm/yr) = (F scfm) * (60 min/hr) * (8760 hr/yr) Fa (Mscfm/yr) = 526 * F
Elevated Flare System Flare Tip Steam Ring Dry Seal Knockout Drum Pumpout Pump
Flare Knockout Drum
Flare Stack
PI TI Instrument Air Vent Emergency Gas Purge
Switch
LIAH
LGR
Solenoid Valve (With Manual Reset)
RO RO
Purge Gas
Gas To Pilot
PI
TAH
Grade
M
Pilot Ignition Systems Locate At Flare Knockout Drum
Normal Gas Purge Steam
Pressure Relief From Process Units
Slop To Slop Tank
PI
PC
Fuel Gas
Plant Air
Ground Flare System
Flare Knockout Drum
Knockout Drum Pumpout Pump
PI TI
LGR
LIAH
Switch
PI
Instrument Air Vent
Emergency Gas Purge
Solenoid Valve (With Manual Reset)
Ground Flare Retention Dike Burners Grade
M
Stage Header
PO PO Normal Gas Purge
Purge Gas
Main Header PC
Pressure Relief From Process Units
Slop To Slop Tank
Gas To Pilot
PI
Pilot Ignition Systems Locate At Flare Knockout Drum PC
Fuel Gas
Plant Air
Two Stage Flare System (Elevated/Ground) Flare Tip
Seal Flare Stack Flare Knockout Drum
Knockout Drum Pumpout Pump
PI TI
LGR
LIAH
Switch
PI
Instrument Air Vent
Water Seal
Solenoid Valve (With Manual Reset)
Enclosed Ground Plane
Gas To Pilot
M
Pilot Ignition Systems Locate At Flare Knockout Drum
Emergency Gas Purge RO RO
PI Normal Gas Purge
Purge Gas
Pressure Relief From Process Units
PC
Slop To Slop Tank
Water
Fuel Gas
Plant Air
Grade
Flare Stack
Structure Self Supporting Guy Supported Derrick Type
Demountable Derrick Single-Section Riser
Normal Position is “A” then can be lowered for work on the tip to position “C” Allows for easy replacement of tip
RE/U&O Flares-12
Demountable Derrick-Multiple Section Riser
Riser assembled in sections Designed to accommodate multiple risers Designed so that one flare can be taken out of service while others are still in operation
RE/U&O Flares-13
Conventional Pressure Relief Valve
RE/U&O Flares-14
Balanced-Bellows Pressure Relief Valve
RE/U&O Flares-15
Pop-Action Pilot-Operated Valve (Flowing Type)
RE/U&O Flares-16
7
Radiation Theory
6 5
Exposure Times Necessary to Reach the Pain Threshold
4 Threshold of Pain
3 2
Safe Limit
440 Btu/(hr) (ft)2
1 0
10
550 740 920 1500 2200 3000 3700 6300
30
40
Exposure Time, Sec.
Radiation Intensity Btu/hr-ft2
20
Kilowatts per M2
Times to Pain Threshold (Seconds)
1.74 2.33 2.90 4.73 6.94 9.46 11.67 19.87
60 40 30 16 9 6 4 2
50
60
Contours of Radiant Heat Intensity Safe Boundary (440 Btu/Hr/Sq.Ft.) Boundary for Radiant Heat Intensity (1500 Btu/Hr/Sq.Ft.) - Normally Fenced in with Warning Signal Protection Required for Equipment
Protection Required for Personnel Boundary for Radiant Heat Intensity (3000 Btu Hr/Sq.Ft.)
Environmentally acceptable combustion Tips normally proprietary in design Flame stability Ignition reliability Exit velocity 1 to 600 ft/s (.3 to 183 m/s) Exit velocity at 50% of sonic velocity Multiple pilot burners Surrounding windshield
Flare Tip
Flare Tip Design
Flare Tip Design Considerations Design for maximum flow rates – Design for maximum temperatures – Design for wind conditions – Design for minimum flow rates –
Pilot and Ignition Systems
Continuously burning pilots Flame front generator –
–
–
Fuel gas and air admitted to the ignition pipe in a combustible ratio Gas is ignited by an electric spark Flame travels through the pipe
Flame Front Generator Ignition System
F
Air
B
D
A To Pilot #1
H J Gas
To Pilot #2 To Pilot #3
E C
Gas To Pilots
Pilot Burners
Automatic systems may be activated by: Thermocouples – Infrared Sensor – Ultraviolet Sensor (ground flare application) –
Installation of Thermocouples Correct Installation
Incorrect Installation
Pilot Windshield
Allows pilot to operate at wind speeds greater than 100 mph Should always be specified Prevents misreading of the thermocouples
Pilot Gas Requirement
The average pilot gas consumption based on an energy-efficient model is 70 scf/hr. The annual pilot gas consumption (Fp) is calculated by: • •
Remove debris manually or by high pressure blowing
Plugged Pilot Tip
Unsaturated Fuel Hydrocarbons
Remove manually or by high pressure blowing then return to fuel gas
Damage Pilot Tip
Pilot tip has increased in size; Pressure drop in pilot decreased; Fuel/Air mixture more lean
Replace pilot tip
Incorrect Fuel
This can be determined by fuel sample; if hydrogen concentration has increased significantly then flashbacks may be audible and visible
Return to design fuel gas; Pilot modifications may include: replace pilot orifice; adjust air door; replace pilot entirely RE/U&O Flares-28
Purging
Flare purge gas –
Any gas which cannot go to dew point under any condition of operation • • •
–
Fuel Gas Inert Gas Nitrogen
Purge Rate •
•
Flare Stack — Linear velocity 1FPS to 5FPS (.3 to 1.5 m/s) Flare stack with molecular seal — 0.10 FPS to 0.20 FPS (.03 to 0.06 m/s)
Purge Gas Requirements
Prevents flashback problems Flare operates at positive pressure Purge all subheaders (upstream) .04 feet per second to 1 feet per second (.01 meters per second to 0.33 meters per second)
F (Mscf/yr) = (0.04 ft/sec)*((PI*D^2/4)/144 ft2))*(3600 sec/hr)*(8,760 hr/yr) F (Mscf/yr) = 6.88*D^2
Dry Seals
Molecular Seals
Double Seals
Fluidic Seals
Airrestors
Molecular Seal
Flare Assembly
Molecular Seal Liquid Drain
Prevents explosions Prevents entry of air Reduces purge gas Performs silently with small pressure drop
Smokeless Flare Operation Smokeless Operation
Smoking
US EPA allows smoking for Only 5 minutes per hour
Steam Requirements and Smoke Suppression Methods
In general, the following equation can be used: Wsteam (lb/hr) = Whc (lb/hr) * [0.68-(10.8/MW)]
Smoke Suppression Methods – – – –
Steam injection High pressure gas injection Low pressure air Internal energized flare
Automatic Steam Control Field Of View Steam Nozzles
Steam Control Valve
Monitor Flux Density Signal Controller Control Scheme
Automatic Steam Control
Minimizes steam consumption
Controlled by the flame appearance
Calibrated to a particular frequency in the infrared spectrum
Knockout Drums
Principle Features –
– – – –
Complete removal of either slugs or mists of liquid (300 microns to 600 microns) Recovers valuable condensed hydrocarbons Ends maintenance difficulty caused by “Wet” gases Used as the base for the flare riser Ends “Wet Gas” control problems
The allowable vertical velocity in the drum may be based on the necessity to separate droplets from 300-600 microns in diameter.
Truck Loading Vapor Control Flare
Achieve high destruction efficiencies through the loading cycle
Systems range in size from 100 BPH to 25,000 BPH
Enclosed burners can be easily tested for emissions
Troubleshooting Enclosed Flares Problem
Cause
Action
High Frequency Noise
Most likely associated with steam injection
Check steam quality and properties
Combustion Roar (low frequency)
Intense combustion
Check flare gas pressure and steam quality
Visible flame
Excess flow
Check diverting water seal or valve
Smoke
Air starvation
Check wind fence for blockage or is wind condition unusual
Smoke
Low gas pressure
Check bypass relief devices and staging valves
Smoke
Steam/support air shortages
Check steam supply or blowers RE/U&O Flares-39
Coupled Effects of Temperature and Time on Rate of Pollutant Oxidation Pollutant Destruction, %
Residence time of gases in combustion chamber calculated from: t = V/Q t = Residence Time (s) v = Chamber Volume (ft3) Q = Gas volumetric flow rate at combustion conditions (ft3/s)
Schematic of a Thermal Incinerator Fume
Fuel
Exhaust
Combustion Air (Fume)
Typical Marine Vessel Loading System Product Loading Arm Product from Storage Tanks Vapor Arm
Natural Gas/ Inerting Gas Enriching Gas Detonation Analyzer Arrestor
Vapor Mover
Hydrocarbon Vapor to Control Device
Knockout Drum(s) Discharged Vapors Sump Pump
Ship or Barge Dock Facilities
Condensate to Tanks
Shoreside Facilities
Flare Gas Recovery Compressor
Flare gas recovery compressor designed to capture flare gases and compress to fuel gas pressure Reduce natural gas purchases RE/U&O Flares-43
Flare Gas Recovery Compressor
Difficult service for a compressor Wide range in Volumetric flow and MW Dirty Service - water, rust, H2S, CO2 and HCl Corrosion and Fouling
RE/U&O Flares-44
Liquid Ring Compressor Type Operates on the rotary liquid piston principle The shaft and the impellers being the only moving parts Shaft and impeller assembly is mounted eccentrically relative to the pump casing As the impeller rotates the water (which is continually supplied to the pump), is forced outwards by centrifugal force to form a liquid ring revolving concentric to the pump casing
RE/U&O Flares-45
Source Reduction Program
Locate relief valve leaks Carryout repairs to reduce amount of gas going to flare Check each relief valve every 3 to 6 months Leakage could occur through normal wear and tear on the valve Leakage could occur due to incomplete closure RE/U&O Flares-46
Source Reduction Program
Potential Saving of $1,000,000 per year have been recorded Relates acoustic signal level to gas losses for various valve types of different valve sizes and working pressure range
Device extremely portable
Can approximate flowrates and associated dollar values
RE/U&O Flares-47
Flare Flow Meters: Ultrasonic “Time of Flight” Technology
Panametrics of Waltham Massachusetts Proprietary algorithm to determine instantaneously the molecular weight and mass flow rate of the flare gas
Meter is used to conserve energy and reduce product loss by identifying sources of leaks into the flare systems
Reduces energy usage by accurately controlling the amount of steam fed to the flare tip RE/U&O Flares-48
