Gas analysis and gas flow measurement in a biogas plant

1. Energy from Biomass and Biogas Gas analysis and gas flow measurement in a biogas plant Ho Chi Minh City, 16 September 2013

2. Gas analysis and gas flow measurement in a biogas plant • Introduction company BINDER • Thermal dispersion mass flow measurement • Typical challenges and solutions • Summary and conclusions

3. Binder Group Binder Group AG Finance Holding Binder Engineering GmbH Sales & Service Companies in DE / F / CH / NL / B / Singapore, China BINDER GmbH Manufacturing Company for Gas Flowmeter, Gas Analyzer and Control Systems with followingproducts: COMBIMASS®/ VACOMASS® / CAMASS® INSTRUM AG Manufacturing Company for Stainless Steel Pressure Regulators and Valves BETA B.V. Manufacturing Company for Pressure and Temperature Switches www.bindergroup.info

4. BINDER Gas flow measurement

5. BINDER Gas analysis

6. Basics of thermal dispersion technology The principle: Gas flows by a heated sensing element and causes cooling down of the element by the mass flow (molecules) direct mass flow measurement, unaffected by gas pressure and temperature changes Measurement is based on a PT 100, an additional non-heated sensor is used as a reference. The amount is directly related to the mass flow.

7. Typical challenges in biogas applications • Outdoor installation – operation for years under the sky – rain, direct sun light, snow, ... • biogas is highly corrosive • big plants – long distances between the measuring points • ignition potential of methane-air-mixture • the concentration of methane is changing in the biogas • biogas has a high percentage of water vapour (at the top of the digester 100% relative humidity) and contains beside others H2S and NH3

8. Typical challenges and solutions • Outdoor installation – operation for years under the sky – rain, direct sun light, snow, ... • biogas is highly corrosive • Rugged stainless steel design • Sensors are corrosion-proof and resistant against moisture and dirt • No mechanical moving parts

9. Typical challenges and solutions • The concentration of methane is changing in the biogas • (e.g. density changes can cause 2…3% failure) • In combination with a gas analyser station the changing gas composition can be corrected in the flow signal

10. Typical challenges and solutions • biogas has a high percentage of water vapour (at the top of the digester 100% relative humidity) • Humidity correction by either 1. Temperature Method 2. Dew-Point Method

11. Humidity Correction 1. Temperature Method Based on temperature of the biogas and assuming a relative humidity of 100% the water contents can be calculated by standard method – can be used only directly after the digester. Even if a gas cooler is used to dry the gas, directly after the gas cooler the gas is 100% water damp saturated. But gas temperature mustn't be increased due to blowers, direct sun light etc. In these cases temperature method will calculate a wrong (too high) water damp portion. 2. Dew-Point Method Using a special probe, the relative humidity and so the water contents can be determined. The probe is sensitive against H2S, therefore it can be used only after the filter at very low H2S-concentrations.

12. Summary and Conclusions • Conditions in biogas plants request solid and reliable designed products for a safe and stable operation • Thermodynamic and Chemical properties of biogas require sophisticated measurement & control equipment • Combination of gas flow and gas analyser ensures an efficient, reliable and profitable operation of the biogas plant

13. Questions / Remarks? We are happy to receive your feedback, questions and remarks. Jan Talkenberger Manager International Sales jan.talkenberger@bindergroup.info +49 1733069903 Binder GmbH Buchbrunnenweg 18 89081 Ulm, Germany Eddy Eng Manager South East Asia binder.engrg@pacific.net.sg +65 96748286 Binder Instrumentation Pte.Ltd 25 International Business Park, # 04-06 German Centre Singapore 609916