A Numerical Prediction of Stabilized Turbulent Partially Premixed Flames Using Ammonia/Hydrogen Mixture

The objective of this work is to computationally assess the performance of a carbon free ammonia-hydrogen mixture when burnt in a gas turbine like combustor. Recently, utilizing ammonia as an alternative carbon-free fuel for future power, industry applications and achieving clean energy attracted enormous interest. Pure ammonia oxidation is facing many challenges such as high NOx emissions, high ignition energy, slow reactivity and lower laminar flame speeds. Therefore, the use of ammonia/hydrogen mixture provides flame stability and increasing flame speed. In this manuscript a numerical study for a new swirl stabilized combustor for oxidizing ammonia/hydrogen mixture. Numerical two dimensional model simulations of a turbulent flame on Reynolds Averaged Navier Stokes (RANS) including a realizable k-e turbulent scheme with the aid of chemistry mechanism were performed under various conditions. Partially premixed combustion model with flame-let concept was selected and radiation effects are also considered. Validation for the predicted results showed a reasonable agreement when validated with the experimental data. The results discuss the influence of changing inlet pressure and equivalence ratio on the stability and the characteristics of unburnt NH3 and NO emissions. Results show that for constant operating conditions such as constant equivalence ratio of 0.8 that increasing hydrogen content resulted in increasing NO emission. Also, for constant ammonia/hydrogen concentrations, NO emissions increases with equivalence ratio then reduced at rich conditions and NH3 emissions are generally low. Equivalence ratio lower than 1.2 will be preferable to reduce the amount of unburnt NH3 formation.

Hydration of natural gas hydrogen mixture test equipment

The use of hydrogen as an energy source is advantageous because its combustion processes only produce water vapor, but not carbon dioxide. This excess energy can be stored in underground gas storage facilities, where it is delivered mixed with natural gas. In gas- and oil industry the formation of hydrate crystals can cause significant damages. A huge amount of hydrate crystal is formed, it can cause hydrate plugs in the pipeline. Like natural gas, hydrate formation occurs in the case of a natural gas-hydrogen mixture. The paper presents a method which can be used to study hydrate formation in natural gas-hydrogen mixture.

INVESTIGATION OF EFFICIENCY OF NATURAL GAS DRYING BY ABSORPTION AND ADSORPTION METHODS

В статье проанализированы современные методы осушки природного газа для дальнейшей переработки его в метано-водородную смесь. Приведены результаты исследования абсорбционной и адсорбционной осушки природного газа жидкими реагентами (этиленгликолями) и твердыми адсорбентами (цеолитами и бентонитами). Показано, что природные бентонитовые глины обладают сравнительно небольшой адсорбционной активностью, их активация водными растворами Na2CО3 и H2SO4 способствует повышению адсорбционной активности, и их применение в комплексе с другими адсорбентами способствует значительному повышению процессов адсорбции. Авторами показана возможность и необходимость дальнейших исследований поиска эффективных методов активации бентонитовых глин. The article analyzes modern methods of drying natural gas for further processing it into a methane- hydrogen mixture. The results of studies of absorption and adsorption drying of natural gas with liquid reagents (ethylene glycols) and solid adsorbents (zeolites and bentonites) are presented. It is shown that natural bentonite clays have a relatively small adsorption activity, their activation with aqueous solutions of Na2CO3 and H2SO4 increases the adsorption activity, and their use in combination with other adsorbents contributes to a significant increase in the adsorption processes.The authors show the possibility and necessity of further research to find effective methods of activation of bentonite clays.