文档介绍：Replacing High-Bleed Pneumatic Devices - EPA更换高引气动装置- EPA
Pneumatic Devices
Pneumatic devices are found in everyocess Measurement
Liquid Level
Pressure
Temperature
Flow
Weak Signal Bleed
(Continuous)
Strong Signal Vent
(Intermittent)
Process Flow
Control Valve
Valve Actuator
Strong Pneumatic Signal
Weak Pneumatic
Signal (3 - 15 psi)
Regulator
100+ psi
Gas
Regulated Gas Supply
20 psi
Sources of Methane Losses
As part of normal operations, pneumatic devices release natural gas into the atmosphere
High-bleed devices bleed in excess of 6 scf per hour
Equates to >50 Mcf per year
Typical high-bleed pneumatic devices bleed an average of 140 Mcf per year
The actual bleed rate is largely dependent on the device’s design
Magnitude of Methane Losses
Major source of methane losses from the natural gas industry
Pneumatic devices are used throughout the natural gas industry
Between 90,000 to 130,000 in the transmission sector
Over 250,000 in the production sector
In the distribution sector most pneumatic devices are non-bleeding pressure regulators
Losses from Pneumatic Devices
Gas Industry Oil Industry
Production 31 Bcf 22 Bcf
Processing 16 ---
Transmission 14 ---
Total 61 Bcf 22 Bcf

Total Gas/Oil 83 Bcf/yr
Three Options for Reducing Losses
Option 1: Replace high-bleed devices with low-bleed devices
Option 2: Retrofit controller with bleed reduction kits
Option 3: Maintenance aimed at reducing losses
Option 1: Replace High-Bleed Devices
Most applicable to:
Controllers: liquid-level and pressure
Positioners and Transducers
Suggested Action: Evaluate replacements
Replace at end of device’s useful life
Early replacement
Economics of Replacement
a All data based on Partners’ experiences. See Lessons Learned for more information.
b Range of incremental costs
c Gas price is assumed to be $3/Mcf.
Economics of Retrofit
a On high-bleed controllers
b All data based on Partners’ experiences. See Les