Conclusion
3
CHAPTER 6 CONCLUSION 6.1 Conclusion The process design, plant erection and some operational experiences of an innovative biogas upgrading plant have been presented. The plant produces approximately 100m³(STP)/h of fully-fledged natural gas substitute (biomethane) and delivers this stream to the public natural gas grid either on a local grid level (up to 3bar) or, during the summer months, to a regional grid level with up to 60 bar. The upgrading is based on the membrane separation process Gas Permeation and allows low energy consumption as well as very low methane losses. The quality of the upgraded biomethane is controlled continuously regarding various unwanted or malicious substances to assure the agreement with the quality described by Austrian laws.
description
bio
Transcript of Conclusion
CHAPTER 6
CONCLUSION
6.1Conclusion
The process design, plant erection and some operational experiences of an innovative biogas upgrading plant have been presented. The plant produces approximately 100m(STP)/h of fully-fledged natural gas substitute (biomethane) and delivers this stream to the public natural gas grid either on a local grid level (up to 3bar) or, during the summer months, to a regional grid level with up to 60 bar. The upgrading is based on the membrane separation process Gas Permeation and allows low energy consumption as well as very low methane losses. The quality of the upgraded biomethane is controlled continuously regarding various unwanted or malicious substances to assure the agreement with the quality described by Austrian laws.
The relevant legislative framework concerning the gas quality which is given by the Austrian laws OEVGW G31 and G33 has been presented and subsequently the upgrading necessities to produce such a gas have been developed. The requirements for a continuous online gas analysis system for several gaseous species have been shown.
The biogas upgrading plant commissioned in Bruck/Leitha has been presented in detail and some information on the plant behavior has been given. It has been shown that the upgrading process is very stable and continuous concerning gas quality and quantity. Finally, some conclusions on electrical power consumption and energy efficiency of the biogas upgrading process have been made.
Subsidiary, a dynamic process simulation model for the Gas Permeation plant has been developed to act as a test field for the planned control strategies. Together with some plant specific data even the parameterization of the implemented PID-controllers has been supported. Moreover, deeper insight into the dynamic phases of plant startup and shutdown has been generated.
In the near future, reliable and well-founded data on overall performance parameters will be compiled. These parameters will include power consumption and electrical efficiencies for the whole range of possible product gas flows, methane slip in the plant Offgas for several load scenarios as well as a first estimation on membrane life expectancy. The last point might be one of the most interesting questions of this new process. The dynamic process simulation model will be further evaluated using experimental data from simple and small laboratory scale plants as well as from more complex upgrading plants like Bruck/Leitha. Additionally, a detailed scientific analysis of another Gas Permeation biogas upgrading plant will be carried out. This plant is situated in Margarethen/Moos, comprising quite similar process technology, but has about a third the size of Bruck/Leitha. Besides, this plant does not feed the produced biomethane to the public natural gas grid but feeds its own Bio-CNG-fuelling station. The biomethane is compressed up to about 250bar and can be fuelled into any commercial CNG-vehicle as a 100% renewable automobile fuel. This might be a very interesting concept in times of huge discussions on the maximum blending percentages of renewable fuels to gasoline and diesel.
