Mixtures of coal/waste tires, coal/waste plastics and coal/waste cotton were pyrolyzed in the laboratory pyrolytical unit built in IRSM AS CR Prague. Non-caking hard coal (mine Lazy) and its mixtures with some organic wastes were pyrolyzed in a quartz reactor inserted in a vertical tube furnace. The main product yields (coke, tar, gas and reaction water) documented exhibit entirely different influence of added waste. Results demonstrated that co-pyrolysis is meaning full in case of waste tiers and plastics. However, in case of co-processing with waste cotton (natural textile), the results are not promising., Vlastimil Kříž and Zuzana Brožová., and Obsahuje bibliografii
The two stage co-pyrolysis method for obtaining of hydrogen is described. In the course of the heating of the mixture of bituminous coal with polyisoprene and styrene-butadiene polymers (co-pyrolysis), a considerable amount of hydrogen and hydrocarbons is released in dependence on the process conditions. The experiments proved that the amount of hydrogen increased already with slightly increased heating rate (5 K min-1 ) in comparison with the amount obtained at a common heating rate (3 K min-1) and, further, with the addition of the second (cracking) stage for further thermal splitting of release d hydrocarbons into hydrogen (and carbon), preferably at a temperature of 1200 ºC., Pavel Straka and Vlastimil Kříž., and Obsahuje bibliografické odkazy
A mineralogical study of the weathering crusts rich in P and Mn from the locality Hodušín - Božetice at Milevsko is presented. The locality belongs to the central part of the variegated group of Sušice and Votice in the Moldanubian Unit. From the analytical methods used, the IR-spectroscopy yielded satisfactory results. The main crust components subjected to weathering are apatite (of a CarHap B - dahllite type) and Mn-minerals (massive black psilomelane, the needle-aggregates probably comprise a poorly recrystallized psilomelane). Disintegrated rocks consist of a mixture of clay minerals, calcite and relicts of primary minerals (quartz, K-feldspars, albite, pyroxene and rutile). The origin and the source material of these crusts rich in P and Mn can not be unambiguously determined. Apatites without CL-effects indicate that the weathering crusts have originated in a strongly oxidative environment. Well documented neighbouring occurrences of phosphate minerals in the variegated group of Sušice and Votice are associated with graphitic rocks. Optical and quantitative chemical analyses of the rocks suggest that the source of apatite could possible be calc-silicate rocks (erlans) close to the graphitic rocks. Hypothetically, the metaphosphorite layers in the variegated Moldanubian Unit can also be considered a possible source of phosphorus., M. Brož, M. Kovářová, Z. Losos, M. Linhartová and V. Vávra., and Obsahuje bibliografii
In the near future, hydrogen will become an important fuel which may be able to resolve local problems connected with air quality. Hydrogen-propelled transport means are being developed and are already used in the automobile industry. Since the combustion of hydrogen does not produce any emissions of carbon oxides but only water, hydrogen is considered as a key fuel of the future. Hydrogen is abundantly present all over space and can be obtained from a number of resources, be they renewable or non-renewable. Global production has so far been dominated by hydrogen production from fossil fuels, with the most significant contemporary technologies being the reforming of hydrocarbons, pyrolysis and co-pyrolysis. Plasma cracking is still in the developmental stage. The preferred method of hydrogen production on an industrial scale is steam reforming of natural gas for its low operational and production costs. When the operational costs of steam reforming and partial oxidation are compared, partial oxidation seems to be a more acceptable process, but the subsequent shift makes this process more expensive. Pyrolysis processes have acceptable investment costs and besides the production of hydrogen also satisfactory yields of oils. Two-stage co-pyrolysis is suitable considering its acquisition of a high amount of hydrogen from mixed charges. It is apparent that the co-pyrolysis of organic materials with coals is a process for hydrogen production capable of competing. It can therefore play a significant role in the future., Olga Bičáková and Pavel Straka., and Obsahuje bibliografii