1/2011
Hydrogen production and its utilization for renewable energy sources regulation
The scope of the paper is to describe processes and economy of hydrogen production and utilization and possible future trends. Hydrogen, regarded as perspective fuel of future, should serve as a suitable energy carrier with its unique properties. The aim of the second part is to introduce hydrogen as a tool for regulation of renewable energy sources with special focus on photovoltaic energy.
Coal reserves assessment in the Czech Republic
The paper deals with coal and lignite reserves assessment using predefined criteria. According to these criteria, four categories of reserves are distinguished – geological, balance, out-of-balance, and workable. The criteria include qualitative parameters of the feedstock, geological characteristics of the deposit, and technical mining conditions. Reserves accounting, including their decrease due to extraction and other changes caused by more detailed specification of the deposit, is provided in the form of national balance.
An alternative way of hydrocarbon gases drying
Water adsorption into triethylene glycol is the most common method for natural gas drying today and the only one used in the Czech Republic. Since 1960 many patents has been accepted, many studies has been done (even as a pilot plant experiments) suggesting adsorption way of natural gas drying. Despite the fact that adsorption drying has several cardinal advantages in comparison with absorption technology, only a few hydrocarbon gas drying adsorption technologies work in the world (Sosnogorsk, Kirchheilingen, Anwil-Wloclawek). The reasons can be just historical. The submitted work explores available knowledge and technological data on adsorption drying processes of hydrocarbon gases.
Biogas treatment
Biogas from WWTP or waste site is used first of all for heat and electric production. Therefore is necessary to remove problematic compounds, especially organosilicon compounds. For dependability of cogeneration units it´s necessary to install technology for removing siloxanes from biogas. At WWTP in Prague – Bubeneč was built special pilot unit in 2009 for testing of varies industrial produced adsorbents to siloxane removal from biogas. This unit works with real biogas with the aim – to find the optimal adsorbent for capture of siloxanes from biogas.
Trends of the air quality in North-Western part of Czech Republic since 1990
Since 1990 a significant transformation of the ambient air quality of North-Western part of Czech Republic proceeded. For examination of that process a data set comprising concentration of criteria pollutants (SO2, NO2, CO, ozone, suspended particle matter and arsene) was evaluated. Those data were collected by Czech Hydrometeorological Institute during 1990-2008 period in automatic air quality monitoring system network (AIM) as the main data source the database Air Quality Information System (ISKO). Nine stations of that system included in the data set represent the air quality of NW part of Czech Republic and two stations were used for characterization of the Central part of Czech Republic during the time period. The ambient air quality in NW part of Czech Republic significantly improved during this period and became almost identical with the ambient air quality of the other parts of Czech Republic except capital and/or Ostrava industrial zone. The main sources of the air pollution of the NW part of Czech Republic are the road traffic and domestic heating units operation.
Separation of CO2 from biogas
The biogas must be purified from undesirable compounds before its using as a fuel in engines. First of all the CO2 separation is necessary. Furthermore some other undesirable substances, such as hydrogen sulfide and organic silicon compounds, which can damage the engine, have to be removed from biogas. At the Waste Water Treatment Plant Prague – Bubeneč were carried out tests using adsorption apparatus for CO2 separation from biogas. The regeneration of saturated adsorbents was carried out using vacuum. The breakthrough curves for CO2 onto varies commercially produced adsorbents were measured and the loadings capacities for CO2 were conseguently calculated.