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A felszín alatti hidrogéntárolás kőzetalkotó ásványokra gyakorolt hatása a Pannon-medencében

Effect of subsurface hydrogen storage on rock-forming minerals in the Pannonian Basin

Scientia et Securitas
Authors:
Orsolya Gelencsér
,
Péter Tóth
,
Tibor Németh
,
Zsuzsanna Szabó-Krausz
, and
György Falus

Összefoglalás.

Az energiaigény és a megújuló energiaforrásokból származó kínálat között fennálló szezonális eltérés áthidalható a hidrogéngáz bevezetésével az energiaellátásba. A nagy léptékű energiatárolás hidrogén formájában a felszín alatti térben lehetséges. Azonban a kőzet pórusterében az injektált hidrogén hatására végbemenő reakciók nemcsak a kitermelendő hidrogén mennyiségét és minőségét csökkentik, de a kőzet hosszabb távú állékonyságát is ronthatják. A Kárpát-Pannon régióban jelentős mennyiségben találhatók porózus kőzetek, amelyek hidrogéntárolásra is alkalmasak lehetnek. Ugyanakkor, ezek a kőzetek változatos ásványos összetételük miatt reakcióba léphetnek a hidrogénnel. Vizsgálatunk célja, hogy megismerjük a kőzetalkotó ásványok viselkedését pórusvíz és hidrogén jelenlétében, amely elengedhetetlen a rezervoár tárolási potenciáljának felméréséhez.

Summary.

One of the key substances in the modern-day energy transition is hydrogen, which can be utilized as an energy storage chemical substance. To store hydrogen on the scales required for global hydrogen economy, porous geological formations should be considered. However, geochemical challenges associated with hydrogen storage in sedimentary formations are still not well understood. Mineral dissolution and precipitation, as a result of hydrogen injection into the rocks not only can decrease the quality and the quantity of the stored hydrogen but may have an impact on the rock integrity as well. The Carpathian Pannonian region is rich in porous rocks, which could serve as hydrogen storage sites. However, many of them show various mineralogical compositions, which could behave differently under high hydrogen partial pressure. The main objective of our study is to predict geochemical reactions among rock-forming minerals, pore water and hydrogen. For this purpose, we apply analytical techniques and geochemical modeling.

The subject of this research is the Late Miocene Szolnok Sandstone Formation located in the Pannonian Basin, Carpathian-Pannonian Region. In the future this Formation can play a significant role in hydrogen storage, due to its favorable reservoir geological and petrophysical characteristics.

X-ray diffraction analyses were carried out, polished and thin sections were prepared for petrographic and geochemical analyses. The collected data were used in the PHREEQC modeling environment. In the first stage, equilibrium batch models were made to assess the potential long-term impacts of hydrogen on the reservoir rock and the effect of the geological environment. The modeling results of the project showed that hydrogen almost does not react with silicates (e.g., quartz). Possible hydrogen loss can occur due to redox reactions. Pyrite (FeS2) can react with hydrogen producing hydrogen sulfide (H2S) and since petrography has revealed that the studied sandstones have pyrite as accessory mineral.

Open access

Abstract

To overcome the problems of seasonality and geographical location in fruit production and processing, the production of aseptic semi-finished juice is an excellent solution. Even without refrigeration, aseptic pressing has a shelf life of more than a year, making it possible to produce finished products all year round. The production technology involves the addition of ascorbic acid to the pulp to fix or preserve colour. There is an increasing customer demand for ascorbic acid substitutes on the international market. In Hungary, one of the most important exports is aseptic sour cherry juice. In our work, ascorbic acid used for colour fixation was replaced by acerola concentrate. The anthocyanin content and colour coordinate values (L*, a*, b*, H, C) of aseptically filled sour cherry juice were determined and compared with the control sample during the 12 months of storage.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Viktória Zsom-Muha
,
Lien Le Phuong Nguyen
,
László Baranyai
,
Géza Hitka
,
Zsuzsanna Horváth-Mezőfi
,
Gergő Szabó
, and
Tamás Zsom

Abstract

Among improper harvest and/or postharvest storage conditions, the effect of direct sunlight plays an important role in quality degradation of potato resulting in the development of green surface color based on chlorophyll formation associated with the formation of poisonous chemicals – glycoalcaloids – known as α-chaconine and α-solanine. Yellow skinned and fleshed potatoes with or without visible initial marks of green surface color were stored at normal room temperature under direct natural (sun)light conditions for almost two months. The aim of this study was the preliminary investigation of the sunlight induced formation of chlorophyll related compounds in potato indirectly by the detection of chlorophyll development. This attempt was based on nondestructive determination of chlorophyll related spectral and fluorescence indices for both sunlight exposed and unexposed potato sides. For both potato groups the chlorophyll content related DA-index® and chlorophyll fluorescence characteristics (F0, Fm, Fv and Fv/Fm) increased during the storage period representing chlorophyll formation. In the case of Fm, Fv and Fv/Fm values, the yellow samples reached the values of the initial spotted green samples by the 7th–9th days. From this time, the chlorophyll fluorescence values changed only minimally. After storage day 34, in the case of both at day 0 yellow and green spotted potatoes, the sunny side's F0 value was lower than that of shaded side. Close relationship was found between the results of Walz monitoring-PAM (Pulse Amplitude-Modulated) chlorophyll fluorometer and the PSI (Photon Systems Instruments) chlorophyll fluorescence imaging device (e.g. Fv R2 = 0.7226). According to our preliminary results, the Vis/NIR DA-meter®, the monitoring-PAM and the chlorophyll fluorescence imaging fluorometers were found to be suitable nondestructive devices for further investigations concerning the postharvest chlorophyll formation based greening phenomena, which is associated with solanine development in potato.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Zsuzsanna Horváth-Mezőfi
,
Emese Bátor
,
Gergő Szabó
,
Mónika Göb
,
Zoltán Sasvár
,
Lien Le Phuong Nguyen
,
Koppány Majzinger
,
Karina Ilona Hidas
,
Anna Visy
,
Géza Hitka
, and
Tamás Zsom

Abstract

Ethylene has key roles in triggering and speeding up ripening processes, which in tomatoes take the form of various qualitative changes. Tomatoes, just like all climacteric fruits, need a continuous ethylene exposure to accelerate ripening. Therefore, it is possible to use ripening regulators preventing ethylene binding. According to some studies, chlorophyll fluorescence measurements can be used at least as efficiently as tristimulus colorimetry classifying tomatoes based on maturity. Measurements were carried out by treating fresh tomatoes with 1-MCP (1-methylcyclopropene) at six different stages of ripening and studying the changes in chlorophyll content related quality characteristics (e.g. surface colour, chlorophyll fluorescence) during postharvest storage (two-week refrigerated storage at 15 °C followed by a two-week shelf life). According to our results, chlorophyll content and photosynthetic activity of the treated samples decreased much less than those of untreated ones. Additionally, anti-ripening treatment proved to be more effective on tomatoes at an earlier stage of ripening.

Open access