2/2017
Barbora Miklová, Marek Staf, Veronika Vrbová, Lenka Jílková, Veronika Šnajdrová, Veronika Podzemná
Various technologies have been developed to capture carbon dioxide from flue gas using different principles. In recent years, properties of synthetic sorbents, based on hydrotalcite-like compounds, are tested in order to reach high performance of CO2 adsorption and stable capacity for the largest possible number of sorption/desorption cycles. This work is focused on adsorption process, which should be used in post-combustion CO2 capture technology. Based on published studies, sorbents, chemically classified as hydrotalcite-like compounds were prepared. Two different modifications of the sorbent were synthesized: HTlcs without impregnation as well as HTlcs impregnated by potassium carbonate. According to the literature the impregnation process should increase basicity of the sorbents and therefore their sorption capacities should be improved as well. Measurements of sorption capacities of HTlcs were performed in the two different apparatuses: with fixed-bed reactor and with fluidized-bed reactor. During the experiments changes in structure were monitored and the stability of BET surface as well as pore size distribution was evalu-ated after each 10 cycles. In addition all of the above mentioned parameters were compared for both apparatuses. The experiments showed that available performance of CO2 capture on hydrotalcites did not reach satisfactory high values, but, on the other hand, the achieved capacity was highly stable during all desorption and adsorption steps.
SEM photos of the material before and after its cyclical exposition to repeated desorptions/sorptions were made to answer, whether HTlcs undergo sintering or not. It was confirmed that no negative structural changes occur after ten cycles and the sorbent is therefore stable at given experimental conditions.
Eliška Purkarová, Karel Ciahotný, Marek Šváb, Siarhei Skoblia, Zdeněk Beňo
Currently a global problem is finding a solution for the enormous energy demand. Additionally worldwide there are many production plants that varnish their products. During this process are formed various types of wastewaters, which are usually hard to treat due to their chemical composition and high moisture content. One of the technologies that can utilize liquid wastes along with the production of energetically usable gases is supercritical water gasification (SCWG). This paper presents results from hydrothermal gasification of real waste streams from industrial activity, which produces radiators. These wastewaters were gasified in a vertical continuous laboratory apparatus using supercritical water as medium.
Veronika Šnajdrová, Tomáš Hlinčík, Karel Ciahotný
This article focuses on the principles and efficiency of individual storage systems for electricity produced from renewable sources. Electricity storage systems are important means of ensuring constant electricity supply to the power grid. A variety of electricity accumulation systems are used in practical applications. In this work the most commonly used technologies are described.
Marek Staf, Karel Ciahotný, Viktor Tekáč, Tomáš Hlinčík, Erlisa Baraj, Eliška Purkarová, Barbora Miklová, Martin Janák, Veronika Podzemná
The study describes actual experiences with continuous testing of high temperature CO2 sorption on limestones using a unique pilot laboratory fluidized bed reactor. The article summarizes results obtained after mathematic processing of data, collected during longer term measurements. Experiments with cyclically alternated decarbonation and carbonation phases were performed without shutting down the system. Sorption behavior of tested substrate was compared with the same parameters evaluated using two smaller-scale laboratory apparatuses. One of the laboratory apparatuses had a fixed bed reactor, while the other was equipped with quartz-made fluidized bed adsorber. The effect of different heating rates, applied in the three above mentioned apparatuses, on sample sintering of the sample was discussed and documented by appropriate SEM photos.