Sacramento County Department of Waste Management and Recycling - - PowerPoint PPT Presentation

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Oct 28, 2022 310 likes •557 views

Tim Israel, P.E. Sacramento County Department of Waste Management and Recycling Jeremy Zuber, E.I.T. Sacramento County Department of Waste Management and Recycling Tom Morjig Kurz Instruments Drivers Flow Meter Basics Biogas Flow

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Tim Israel, P.E. Sacramento County Department of Waste Management and Recycling Jeremy Zuber, E.I.T. Sacramento County Department of Waste Management and Recycling Tom Morjig Kurz Instruments

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 Drivers  Flow Meter Basics  Biogas Flow Metering Issues  Flow Meter Types  Kiefer Landfill  Use of Wet Gas Meters at Kiefer  Conclusions

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 Federal GHG Inventory  State Inventory  Local Permit Metering Requirements  Energy Project Development  Air District Fees and Title V designation

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 Variable Flows

Flares are designed with up to a 10:1 turndown

 Variable Quality

CH4 Quality can range from 30% to 50%
2% change in CH4 translates into 1% flow error

 Saturated Gas

Big impact on mass flow measurements

 Dirty Conditions

Affects the accuracy of the measuring device

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 Requires Mass Flow Measurement  High Turndown  Can Operate in Dirty Environments  Low O&M Cost

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 Differential Pressure (Orifice

e Plates, es, Pitot t Tubes, s, Venturis ris)

 Thermal  Turbine  Vortex  Ultrasonic  Coriolis

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 Typically an Orifice Plate Type  Consists of an orifice in a straight length of pipe

which creates a pressure drop

 Static pressure, density, temperature and

differential pressure are measured

 Measures Volume  Easy to field-service and have no moving parts  Issues: Poor flow turn down, poor tolerance to

water and dirt, higher operational cost due to large pressure drop

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dP P T Orifice Plate

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 Measures the Heat Transfer From a Heated

Probe to the Flowing Gas

 Easy to Install  Minimal Obstructions and No Moving Parts

Dirt tends to blow past sensor
Ideal for dry gas flow measurements

 Directly Reads Mass Flow  Accuracy Reduced in Wet Conditions (high

reads)

Thermal sensor will read false high from varying

water moisture levels entrained in the gas flow.

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Heated Sensor 5 to 75 °C above process T Process T sensor

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 Owned and Operated by Sacramento County  Part of the County’s Vertically Integrated

System

 Opened in 1967  Approximately 30,000,000 Tons of Refuse in

place

 History of LFG Migration and Groundwater

Impacts

 Aggressive LFG Collection and Control

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 LFG Migration Discovered in Early 90s  High Concentrations Found over 2,000 Feet

From Footprint

 Original System Began Operation in 1997  Flare Station and 15 Megawatt Power Plant  LFG Collection Both Internally and on

Perimeter

 Current Flowrate of 7,000 SCFM  Remnants of Original LFG “Cloud” Remain

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 Achieve Full Backup Capacity In Case of

Energy Plant Shutdown

 Added Second Flare  Upgraded Controls and Added VFDs  New Standard Thermal Flow Meters for Energy

Plant Intakes and New Flare

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 Energy Plant Meters Reading Inconsistent

~20% High

 Spikes in Readings  Attributed to Condensing Gas on Probe

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 Kurz Replaced Standard Meter With Their Wet

Gas Meter (WGF)

 300 °C Overheat Thermal Meter  Eliminated the Condensing Gas Issue  Wider sensor stings to avoid water bridging  Capable of reporting wet and dry gas

flowrates (rates

tes with h or w without

ut H2O gas contribut

ributio ion)  Accuracy Verified Through Onsite Field

Calibration

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Heated Sensor 300 °C above process T Process T sensor

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