On the acoustics of turbulent non-premixed flames

Gas turbines are clean, compact and eÆcient engines for electric power generation. They are used at a large scale to this end and are usually red with natural gas. A novel development is to re them with coal gas produced by a coal gasier. This opens ways to use the huge coal resources in a clean and eÆcient operation. As the combustion properties and conditions of coal gas are very dierent from those of natural gas, it is necessary to redesign the burners\ud and combustors of the gas turbine. Because of the complexity of the burners and combustors in a gas turbine, many diÆculties have to be taken care of

A modeling based study on the integration of 10 MWth indirect torrefied biomass gasification, methanol and power production

This work is focused on the process system modelling of an indirectly heated gasifier (10 MWth) using torrefied wood as feedstock and its integration with methanol and power production using Aspen Plus®. The modelling of the gasification process along with the obtained reaction kinetics were validated with experimental data found in literature. Different processing steps such as gasification, gas cleaning and upgrading, methanol synthesis and energy conversion, were modelled and their performance was optimized through a series of sensitivity studies. The results obtained were then used to investigate the effect of different technologies and the variation of operational parameters on the overall process performance. Three cases were examined: “syngas production” (case 1), “methanol production” (case 2), and “power production” (IGCC) (case 3). Case 1 and case 2 were simulated using sand and dolomite as bed materials respectively, in order to study the incorporation of Absorption Enhanced Reforming (AER) on the syngas and methanol production efficiency. For case 3 the simulation was performed for two different configurations: a conventional Integrated Gasification Combined Cycle (IGCC) and an innovative Inverted Brayton Cycle (IBC) turbine system. Dolomite was used as the bed material for both configurations. For case 1, an increase of 5% in hydrogen yield in the product gas when AER is applied was observed. For case 2, higer values of Cold Gas Efficiency and Net Efficiency (34% and 60% instead of 33% and 55%, respectively) and a slightly lower value of Carbon Conversion (96% instead of 100%) were obtained when AER was employed. Gasification temperature was lowered by 110 °C in this scenario. For case 3, a lower value of Net Efficiency was obtained when IBC was considered (43% instead of 47%), while a value of 60% was obtained for methanol production with AE. Moreover, the results of case 3, showed that the latent heat in the hot syngas is best utilised when IBC is considered. The developed model accurately predicted the composition of the produced gas and the operational conditions of all the identified blocks within the methanol synthesis and power production processes. This way the use of this model as a generic tool to compare the utilization of different technologies on the performance of the overall process was validated.Large Scale Energy StorageEnergy Technolog

Groene keuzes voor de Nederlandse basisindustrie: Klimaatneutrale productie in een circulaire economie

Dit rapport schetst hoe de Nederlandse basisindustrie in 2050 klimaatneutraal en circulair kan produceren. Het is gebaseerd op discussies binnen het Sustainable Industry Lab vanaf medio 2021. De transitie van de basisindustrie is uitdagend, maar de ligging aan de Noordzee en het netwerk van industriële bedrijven, toeleveranciers en kennisinstellingen, maken het plausibel en wenselijk dat Nederland een flinke basisindustrie behoudt. Dat vraagt echter om keuzes, waarover de meningen uiteen lopen. We schetsen daarom ook hoe verschillende sociaal-maatschappelijke toekomstbeelden deze keuzes beïnvloeden

Techno-Economic Comparison of Electricity Storage Options in a Fully Renewable Energy System

To support increasing renewable capacity for a net-zero future, energy storage will play a key role in maintaining grid stability. In this paper, all current and near-future energy storage technologies are compared for three different scenarios: (1) fixed electricity buy-in price, (2) market-based electricity buy-in price, and (3) energy storage integrated into a fully renewable electricity system. In the first part of this study, an algorithm is devised to simulate strategic buy-in of electricity for energy storage. This analysis yields a qualitative decision-making tool for a given energy storage duration and size. Building upon the first part’s findings, an integration study gives insight into expected power prices and expected storage size in a typical northwestern European fully renewable energy system. The integration study shows significant need for electricity storage with durations spanning from one to several days, typically around 40 h. Pumped Hydro Storage and Pumped Thermal storage surface as the best options. The overall levelized costs of storage are expected to be in the USD 200–500/MWh range. Integration of storage with renewables can yield a system-levelized cost of electricity of about USD 150/MWh. Allowing flexibility in demand may lower the overall system-levelized cost of electricity to USD 100/MWh

Acoustic Instabilities in Syngas Fired Combustion Chambers

Gas turbines fired on syngas may show thermo-acoustic combustion instabilities. The theory on these instabilities is well developed. From this theory it can be shown that the acoustic system of a combustion installation can be described as a control loop with a set of transfer functions. The transfer function of the flame plays a decisive role in the occurrence of combustion instabilities. It is however very difficult to predict this flame transfer function analytically. In this paper a numerical method will be presented to calculate the flame transfer function from time-dependent combustion calculations. Also an experimental method will be discussed to determine this flame transfer function. Experiments have been performed in a 25 kW atmospheric test rig. Also calculations have been done for this situation. The agreement between the measurements and CFD calculations is good, especially for the phase at higher frequencies. This opens the way to apply CFD-modeling for acoustics in a real gas turbine situation