4/2010
The possibilities production of hydrogen biological processes
At present, hydrogen is used mainly in a chemical industry for production of ammonia and methanol. In the near future, hydrogen will become a significant fuel which can solve the local problems connected with an air quality. Because the hydrogen is most widespread component on the Earth, it can be obtained from a number of sources, both renewable and non-renewable, moreover, by various processes. This work is aimed to an evaluation of possibilities of the hydrogen production from the renewable sources by biological methods and comparison of effectiveness with the conventional methods.
Immobilization of Heavy Metals from Municipal Solid Waste Incineration Plant Solid Residuals
The article deals with utilization of solid residuals from municipal solid waste incineration with the emphasis on heavy metals immobilization. Important physico-chemical characteristics of monitored ash fractions are summarized and discussed with respect to application in construction industry. Leachability of heavy metals from the solid residuals and from the solidificates with the addition of solid residuals was analyzed and the results were compared with limits from European legislation.
Determination of hydrocarbon dew point in natural gas
Among the qualitative characteristics of natural gas, the hydrocarbon dew point is acquiring an increasingly important role. Its importance will further increase with the increasing diversification. Recent findings on the possibility of hydrocarbon dew point determination in natural gas are discussed in the article.
Experience from brown coal underground gasification in the North Bohemian basin of the Czech Repub
The paper deals with underground brown coal gasification which was tested at several sites in the North Bohemian Brown Coal Basin in the 1960’s. Based on a series of in-situ experiments carried out at that time, operating conditions were defined as well as possibilities and limits of this technology determined especially by geological structure of coal deposit, qualitative parameters of both coal seam and overlaying and underlying strata, and also by technological equipment conditions at that time.
Adsorbents testing for helium purification system of High Temperature Helium Loop in NRI Rez plc.
Within the scope of commissioning of High Temperature Helium Loop (HTHL) in NRI Řež plc. methods of helium purification and purity control are developed. In the first period the research was aimed to capacities of obtainable adsorbents for removal of impurities expected in helium in HTHL. In helium coolant of Very High Temperature Reactor (VHTR) hence in helium in HTHL are expected following impurities: CO, CO2, H2, H2O, CH4, O2, N2. Concentrations of these compounds are not range from approx. 0,1 – 1000 ppmv. During first period of experiments removal of CO, CO2, CH4 and H2O on selected adsorbents was tested in laboratory-scale apparatus. According to results of experiments good adsorbent for H2O and CO2 removal at room temperature seems to be molecular sieve (e.g. Tamis 5A from Axens, France or 13 X from Sigma-Aldrich), relative good adsorbent for CH4 removal seems to be active charcoal from CarboTech company but for good adsorption capacity achievement the adsorber has to be cooled to very low temperature. CO is difficult to retain on adsorbents but it can be effectively oxidized at temperatures higher than 170°C to CO2, which can be removed effectively on molecular sieves.
Research Fund for Coal and Steel – the opportunity for Czech companies
The paper informs about the Research Fund for Coal and Steel (RFCS), which funds research projects related to steel and coal. Both private companies and research institutes may apply. The fund may finance research, pilot, and demonstration projects outside EU Framework Program. The fund is mainly aimed at improving the competitiveness of both coal and steel related fields of industry. Among the priorities of the coal part of the program are improving the competitive position of Community, health and safety in mines, and improvement of the use of coal as a clean energy source. The projects are assessed and monitored by 12 technical groups, 3 of them are focused on coal projects. The fund co-finances successful and accepted projects from its budget in the ratio – 27.8% for coal projects and 78.2% for steel projects. The advantage of funding coal research projects from RFCS is not fully taken by Czech researchers. Mining companies as well as electricity and heat generating companies have great potential to modernize their technologies. This is exactly the right subject area for a project of international cooperation.
Low temperature oxidation of coking coal under real conditions in an open stockyard
Low temperature oxidation seriously deteriorates important coking properties of black coal even under open–air atmospheric conditions. This article deals with real study of low temperature oxidation effects on usefull technological properties of black coal intented for carbonization. Three totally different kinds of coking coal were placed in an open stockyard for four months from june to september 2009. There were relatively mild conditions during an experiment (average air temperature 17,4 °C, average monthly total rainfall 102,4 mm, average sunshine length 195,7 h). It was found that maximum fluidity (Gieseler), dilatation, volatile matters content and gross calorific value decreased significantly from the standpoint of technology. On the other hand swelling index didn´t change according to assumption. The Gieseler maximum fluidity repeatedly proved to be the most sensitive indicator of coking properties impairment in agreement with previous laboratory study. Examined coal samples were ranged based on their reactivity with atmospheric oxygen using available analytical indicators including proximate analysis, ultimate analysis, micropetrographic analysis and FTIR spectroscopy.