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Hydrogen-methane mixtures draw attention due to an idea of injection of hydrogen into natural gas network, thus lowering the need of huge investing in development of hydrogen infrastructure. Extraction of hydrogen from dilute mixtures with natural gas differs from traditional separations, since hydrogen concentration is low. Due to selective absorption of hydrogen from the feed, epy metal hydrides purification achieves high values of separation efficiency. We have experimentally demonstrated successful separation of the hydrogen (10%) - methane (90%) mixture at inlet pressure 9.5 bar by the LaNi4.8Mn0.3Fe0.1 intermetallic compound in one step with roundtrip (absorption/desorption) hydrogen recovery 74% and absorption hydrogen recovery 76%.

Reversible metal hydrides are efficient solution for energy storage for distributed and autonomous power. Heat transfer is the major limiting factor for performance of metal hydride devices. Exothermic hydrogen absorption creates significant temperature gradients due to low effective thermal conductivity of powdered metal hydride beds. As the result of a strong dependence of absorption equilibrium pressure on temperature, this gradients lead to heat and mass transfer crisis and compositional inhomogeneities with high concentration of hydride phase near heat sinks and low concentration in the hot core of the bed. Development of the compositional inhomogeneities is accompanied by significant pressure drops over the bed, which can be measured experimentally. We performed experiments on hydrogen absorption in 1 kg metal hydride bed of of La0.9Ce0.1Ni5 inside a water cooled reactor during charge at constant hydrogen flow within the range of 10-30 st.L/min at 0.59 MPa. Results show that heat and mass transfer crisis starts, when pressure in the reactor near hydrogen inlet becomes close to supply pressure, while pressure on the other side of the bed is lower by 0.15-0.25 MPa. These results confirm development of the hot core inside the bed, where reaction almost stops due to high temperature.

The paper presents a system of regional data assimilation prepared and functioning at the Hydrometcenter of Russia for the COSMO-Ru short-range weather prediction system. It describes the assimilation methods used: both the nudging and latent heat nudging methods incorporated into the model and the developed surface temperature correction module. An optimal scheme for preparing the analysis fields and the assimilation cycle for obtaining refined initial data is also described. The presented scores of numerical experiments with and without assimilation show that the use of the detailed analysis allows improving the skill of the model very-short-range forecast, including the nowcasting interval, for the fields of temperature, humidity, wind, cloud cover, and precipitation. It is shown that the assimilation of precipitation based on radar data also makes it possible to simulate associated convective phenomena, including severe ones, much more accurately.

Extraction of hydrogen from dilute mixtures with natural gas differs from traditional separation processes, since hydrogen is the minor component with low partial pressure. Metal hydrides absorb hydrogen selectively and can be used for purification. Exergy analysis shows that the metal hydride separation of binary mixture of a gas with hydrogen has a maximum at hydrogen content of 5-15%, and the main factors affecting efficiency are the need to spend heat to compensate the reaction enthalpy and pressure losses of methane during filtration through the metal hydride bed. We have experimentally demonstrated successful separation of the hydrogen (10%) - methane (90%) mixture at inlet pressure of 9.5 bar by the LaNi4.8Mn0.3Fe0.1 intermetallic compound in one step with roundtrip (absorption/ desorption) hydrogen recovery of 74% and absorption hydrogen recovery of 76%, which is close to the value of 77% calculated based on the thermodynamic analysis.

The paper presents experimental results of thermal processes investigations in flow type metal hydride hydrogen storage and purification reactor RSP-8(I). Thermal processes in the reactor during hydrogen separation from carbon dioxide are studied. Optimal operation parameters for hydrogen purification and performance efficiency of metal hydride reactor RSP-8(I) are defined experimentally. Investigations of heat and mass transfer inside a vertical metal hydride reactor RSP-8(I) with 1 kg of LaFe0.1Mn0.3Ni4.8 show considerable non-uniformity of pressure inside the bed. If the reactor is charged from the top, the hydrogen pressure at the bottom is lower by 0.2-0.3 MPa, which results in earlier occurrence of heat and mass transfer crisis.

The results of the experimental research of thermal, mass exchange and dynamical characteristics of processes inside the low temperature metal hydride (MH) thermal energy storage system are presented. Single stage pressure driven MH heat storage system of closed cycle concept was studied and tested. Intermetallic compound (IMC) LaFe 0.1 Mn 0.3 Ni 4.8 in the quantity of 5 kg was used as main hydrogen storage/heat emitter element in the reactor. Nominal maximum hydrogen capacity of the reactor is 850 st.l. with though resulting effective volume of cycled hydrogen ended up to be around 240-250 st.l. The reactor type and intermetallic alloy, which were used in the series of experiments, proved to be somewhat suitable for the task, but more advanced heat exchange design along with selection of different type of IMC promise to increase the cycled effective volume along with the system dynamics, resulting in greater thermal energy power output.

The results of the development of metal hydride (MH) reactors for the storage and purification of hydrogen of various types are presented. Two methods of metal hydride purification of hydrogen are presented. The use of the MH method of flow-through purification of hydrogen has high hydrogen recovery rates at high volume contents of hydrogen in the mixture (⩾10% vol.), while the method of periodic evacuation of accumulated impurities is most effective at low hydrogen contents in the mixture (<10% vol.).

We present a simple lumped mathematical model of hydrogen absorption in a metal hydride reactor with a constant flow rate (sub-critical regime) and use it to predict a heat and mass transfer crisis in the reactor. To verify the model we compare calculations with the experiment on hydrogen absorption in the reactor filled with 5 kg of LaNi4.8Mn0.3Fe0.1 alloy with a hydrogen flow rate of 60 stL/min. The analytical model predicts the heat and mass transfer crisis with good precision.

One of the tendencies in mechanical engineering is the transition from sliding friction to rolling friction in part joints moving under load, motor assemblies and machinery. For the present time, planetary roller screws (PRS), which are rolling mechanisms, possess the biggest potential as converters of rotational motion to linear motion. However production of high-precision parts for PRS requires special expensive equipment. The emerging world tendency for reduction of technological costs is to develop nutless roller screws (NRS), which is the most complex PRS part to manufacture. Its production requires an additional machine tool or a universal grinding machine for external and internal grinding. The new rolling NRS has been developed in line with this tendency. This paper focuses on the design and operation of the mechanism and on theoretical studies. A test model and a testing rig have been developed to confirm the results of the theoretical studies and to determine operation parameters of the new NRS. The experiments showed that the newly developed NRS loses to PRS in some parameters, while outperforming it in other. It is also simpler and cheaper to produce and after additional studies and tests rational applications for the newly developed NRS can be found.

Cu-containing and Ce-modified OMS-2 catalysts were prepared at various calcination temperatures using the hydrothermal method and tested for low-temperature CO oxidation. The structure, chemical compositions, and physical–chemical properties of the catalysts were characterized using XRD, N2 physisorption, XRF, Raman spectroscopy, SEM, high-resolution TEM with EDX, TPR-H2, and XPS. The incorporation of Cu into the Ce-OMS-2 sample facilitated the transformation of pyrolusite into cryptomelane, as confirmed by Raman spectroscopy data. In the light-off mode, the Cu/Ce-OMS-2-300 and Cu/OMS-2 samples exhibited higher activity in low-temperature CO oxidation (T90 = 115 and 121 °C, respectively) compared to sample Cu/Ce-OMS-2-450. After a long-run stability test, the Cu/Ce-OMS-X samples demonstrated excellent performance: the T80 increased by 16% and 7% for the samples calcined at 300 °C and 450 °C, respectively, while the T80 for the Cu/OMS-2 increased by 40%. The Cu/OMS-2 and Cu/Ce-OMS-2-300 samples were found to have an increased content of nanodispersed copper sites on their surfaces. These copper sites contributed to the formation of the Cu2+-O-Mn4+ interface, which is responsible for the CO oxidation. The presence of Ce3+ in the catalyst was found to increase its stability in the presence of water vapor due to the higher reoxidation ability in comparison with Ce-free sample Cu/OMS-2.