Capacitive and Infrared Gas Sensors for the Assessment of the Methane Number of LNG Fuels

Liquid Natural Gas (LNG) is an energy source that is becoming more important in energy transition, as the world is facing lower the CO2 emissions and backup sources for wind and solar energy are needed. LNG is becoming a major player not only as fuel for power plants, but also in transport and mobility. However, the composition of LNG varies significantly between the various production locations around the world, and the layering of hydrocarbons with different molecular weights takes place even in LNG containers. This is especially critical for LNG engines, in which the ignition properties of the gas depend heavily on the fuel quality or Methane Number (MN) of the gas. For optimized engine operation and motor management, this fuel quality should be measured regularly, preferably online and by a small and low-cost sensor. This paper presents two sensor solutions for the assessment of the full gas composition. For both sensors, the standard deviation in the composition of the relevant hydrocarbons was low enough to calculate the Methane Number with an accuracy of approximately 1 MN unit. It was demonstrated that the electronic capacitive sensor was better suited to assess the higher hydrocarbons, whereas the infrared sensor showed higher selectivity for the lower hydrocarbons

Monitoring grondgebondenheid melkveehouderij: 2015-2017

Toen de Algemene Maatregel van Bestuur Grondgebonden melkveehouderij op 1 januari 2016 van kracht werd, verkeerde de Nederlandse melkveehouderij in een expansiefase. Naar aanleiding van de groeiende mestproductie kondigde de overheid in juli 2015 de invoering van fosfaatrechten voor de melkveehouderij aan. Voordat dit stelsel per januari 2018 daadwerkelijk werd ingevoerd, zijn in 2017 via het fosfaatreductieplan ingrijpende maatregelen getroffen om de melkveehouderij onder het nationale sectorplafond van de fosfaatproductie te brengen. De genoemde ontwikkelingen hebben hun weerslag gehad op de grondgebondenheid van de melkveehouderij in de periode 2015-2017

Multiparameter Sensor Array for Gas Composition Monitoring

In the energy transition from fossil to renewable resources, gas is foreseen to play an important role. However, the composition of the gas is expected to change due to a wider variation of sources. In order to mitigate potential challenges for distributors and end-users, a new low-cost gas composition sensor was developed that will be able to monitor the composition and energy content of these gas sources, ranging from biogas to liquid natural gas (LNG). Together with industrial and academic partners a gas sensor was realized that can be inserted in an existing gas grid. A first demonstrator was realized that was small enough to be used in low and medium pressure gas pipes (100 mbarg—8 barg). Adding the pressure and temperature data to the chip readings enables to determine the concentrations of methane, ethane, propane, butane, nitrogen and carbon dioxide, including small fluctuations in water vapor pressure and subsequently calculate the Calorific Value, Wobbe Index and Methane Number

A versatile capacitive sensing platform for the assessment of the composition in gas mixtures

The energy market is facing a major transition, in which natural gas and renewable gasses will play an important role. However, changing gas sources and compositions will force the gas transporters, gas engine manufacturers, and gas grid operators to monitor the gas quality in a more intensive way. This leads to the need for lower cost, smaller, and easy to install gas quality sensors. A new approach is proposed in this study that is based on the chemical interactions of the various gas components and responsive layers applied to an array of capacitive interdigitated electrodes. For Liquid Natural Gas (LNG), containing a relative high concentration of higher hydrocarbons, an array of ten capacitive chips is proposed, that is sufficient to calculate the full composition, and can be used to calculate energy parameters, such as Wobbe Index, Calorific Value, and Methane Number. A first prototype was realized that was small enough to be inserted in low and medium pressure gas pipes and LNG engine fuel lines. Adding the pressure and temperature data to the chip readings enables the determination of the concentrations of the various alkanes, hydrogen, nitrogen, and carbon dioxide, including small fluctuations in water vapor pressure. The sensitivity and selectivity of the new sensor is compared to a compact analyzer employing tunable filter infrared spectrometry

Security of Supply in Gas and Hybrid Energy Networks

Reliable energy supply becomes increasingly complex in hybrid energy networks, due to increasing amounts of renewable electricity and more dynamic demand. Accurate modeling of integrated electricity and gas distribution networks is required to quantify operational bottlenecks in these networks and to increase security of supply. In this paper, we propose a hybrid network solver to model integrated electricity and gas distribution networks. A stochastic method is proposed to calculate the security of supply throughout the networks, taking into account the likelihood of events, operational constraints and dynamic supply and demand. The stochastic method is evaluated on a real gas network case study. The calculated security of supply parameters provide insight into the most critical parts of the network and can be used for future network planning. The capabilities of the coupled hybrid energy network simulation are demonstrated on the real gas network coupled to a simplified electricity network. Results demonstrate how combined simulation of electricity and gas networks facilitate the control design and performance evaluation of regional hybrid energy networks

Monitoring grondgebondenheid melkveehouderij : 2018-2019

Toen de Algemene Maatregel van Bestuur Grondgebonden melkveehouderij op 1 januari 2016 van kracht werd, verkeerde de Nederlandse melkveehouderij in een expansiefase. Naar aanleiding van de groeiende mestproductie kondigde de overheid in juli 2015 de invoering van fosfaatrechten voor de melkveehouderij aan. Voordat dit stelsel per januari 2018 daadwerkelijk werd ingevoerd, zijn in 2017 via het fosfaatreductieplan ingrijpende maatregelen getroffen om de melkveehouderij onder het nationale sectorplafond van de fosfaatproductie te brengen. De genoemde ontwikkelingen hebben hun weerslag gehad op de grondgebondenheid van de melkveehouderij in de periode 2015-2019