The Czech Republic is gradually shifting toward a low-carbon economy. The transition process requires measures that will help to contain energy production and help to reduce emissions from the coal industry. Viable measures are seen in carbon capture technologies (CCTs). The main focus is on the environmental and economic comparison of two innovative CCTs that are integrated in the operational Czech energy units. The assessed scenarios are (1) the scenario of pre-combustion CO₂ capture integrated into the gasification combined cycle (IGCC-CaL) and (2) the scenario of post-combustion capture by adsorption of CO₂ by activated carbon (PCC-A). An environmental assessment is performed through a life-cycle assessment method and compares the systems in the phase of characterization, normalization, and relative contribution of the processes to the environmental categories. Economic assessment compares CCT via capture and avoided costs of CO₂ and their correlation with CO₂ allowance market trend. The paper concludes with the selection of the most suitable CCT in the conditions of the Czech Republic by combining the scores of environmental and economic parameters. While the specific case of IGCC-CaL shows improvement in the environmental assessment, the economic analysis resulted in favor of PCC-A. The lower environmental–economic combination score results in the selection of IGCC-CaL as the more viable option in comparison with PCC-A in the current Czech energy and economic conditions.

The expected benefit of composite adsorbents generally consists in their growing applicability, thanks to the combination of the adsorption properties of individual components. Composite adsorbents were prepared as mixtures of kaolin from a Czech deposit (kaolin Sedlec, SK) and two fly ashes (FAs) from a fluidised bed boiler in Czech operations differing in fuel type. The mixtures of SK with FA in a ratio of 50:50% wt. were prepared at 20 °C, 65 °C, and 110 °C in an autoclave. The source materials and composite adsorbents were tested for the adsorption of lead as Pb²⁺, and arsenic as AsO₄³⁻ from model solutions in laboratory conditions. The adsorption of Pb²⁺ proceeded quantitatively on the source materials except SK, and on both the composites, with an adsorption yield of >97% and a low adsorbent consumption (~2 g.L⁻¹). The AsO₄³⁻ adsorption proceeded selectively only on both FAs, with an adsorption yield of >97% again. The adsorption of AsO₄³⁻ on the composite adsorbents achieved a worse yield (˂80%), with about ten times more adsorbent consumption (~20 g.L⁻¹). An increased preparation temperature did not affect the Pb²⁺ adsorption at all, but it reduced the efficiency of AsO₄³⁻ adsorption by up to 30%. The SK–FA composites proved to have promising properties, mostly as cation-active adsorbents.

The effect of adding 10% biochar (B) or sludgechar (SL) on the water regime and adsorption properties of soils was tested on composites prepared by mixing two standard soils of loamy and clay type with B or SL in a 90:10 weight ratio. Water-holding capacity was assessed as initial (2 h) and equilibrium (24 h). Water retention time was estimated by evaporation from saturated samples at 20 °C to a constant weight. The composites exhibited a 60–90% increase in water absorption compared to the individual soils, retaining water up to 3–6 days longer than the individual soils. The adsorption properties were tested for cation (Pb²⁺) and anion (Sb(OH)₆⁻) adsorption and for Pb²⁺ and Sb(OH)₆⁻ co-adsorption from model solutions under laboratory conditions. All samples showed higher selectivity for Pb²⁺, with the adsorption efficiency from 40% to 99%. Sb(OH)₆⁻ adsorption achieved a maximum efficiency of only 10%. Pb²⁺ and Sb(OH)₆⁻ co-adsorptions were efficient for Sb(OH)₆⁻ adsorption, reaching efficiency levels above 95%. At prolonged reaction times, the adsorption efficiency elevated by more than 20%. Only 10% wt. addition of biochar or sludgechar enhanced not only the water regime of soils but also their adsorption capacity for ionic contaminants.

In this article, the results of full-scale experiments on the addition of a sodium sulfide to the ${\mathrm{CaCO}}_3$ slurry circuit in a wet flue gas desulfurization (WFGD) plant are presented. Tests are performed on two comparable WFGD installations (spray tower, 4 spraying levels and two stage gypsum de-watering by hydrocyclones and vacuum belt filter) which allows the investigation of the influence of lignite composition (lignite mined in Poland and the Czech Republic are compared) on the reduction in mercury emission. Additionally, the efficiency of precipitation of metals from the slurry (Hg, Zn, Pb, Cd, Cr, Cu, Ni, Fe, Se, and Mn) is investigated as the result of sulfide addition. For both objects, mercury re-emission from absorber occurs (the concentration of mercury in the chimney is higher than that before the WFGD absorber) and the sulfide addition to WFGD slurry stops this phenomenon. The addition of sulfide works effectively (mercury removal efficiency from flue gas reaches up to 88% for Polish tests and up to 87% for Czech Republic tests). For the tests in the Poland power plant, all of measured metals are precipitated from the slurry (precipitation of metals efficiency varied from 2% for zinc to 88% for mercury), but in the case of the test in the power plant in the Czech Republic, there is no effect on manganese, iron, and lead (precipitation of metals efficiency varied from 6.5% for copper to 86% for mercury). The addition of sulfide works effectively for lignite mined in Polish and Czech power plants under the conditions of similar WFGD installations.

Carbon capture and storage (CCS) technologies are an important step to mitigate CO₂ emissions. This study focuses on CO₂ capture from biomass combustion in fluidized bed boilers using a vacuum pressure swing adsorption (VPSA) process. A pilot-scale VPSA unit was used to evaluate the dynamic adsorption behavior of zeolite 13X and clinoptilolite under realistic operating conditions. Moreover, a simplified one-dimensional isothermal mathematical model of a fixed-bed adsorption column was developed to simulate breakthrough curves to validate whether the model reproduces the observed experimental trends. Experimental results confirmed that fresh zeolite 13X exhibited the highest CO₂ adsorption capacity, while clinoptilolite showed moderate uptake. For both sorbents, a decrease in derived adsorption capacity was observed after prior use. The developed mathematical model successfully reproduced the experimental breakthrough curves, achieving coefficients of determination (R²) up to 0.99 and percentage fit (%Fit) values close to 94% for fresh sorbents, while lower correlations were observed for used sorbents. The model reliably captured the breakthrough curves, validating its applicability for process prediction. These results highlight the effectiveness of combining experimental measurements with modeling to assess sorbent performance and guide further optimization of VPSA processes under realistic flue gas conditions.