3/2012
Laboratory testing oxidation stability of turbine oils
The article deals with monitoring of oxidation stability of turbine oils during their use. The possibility of a substitution of commonly used oxidation test RPVOT for another test was examined. The new test should be simpler and less time consuming in comparison with the common RPVOT test. Therefore, the new PetroOxy tester that is usually used to determine the oxidative stability of motor fuels, was chosen. Test conditions allowing shortening of the testing time to approximately one third compared to RPVOT test were selected and tested. Correlation of the results of oxidative stability determination in used and new turbine oils was suggested.
Flash Plastics Micro Pyrolysis
In recent time waste plastics are very perspective source for energy, fuels or petrochemical compounds production. One of the possible ways how to take advantage of that represents thermal cracking pyrolysis. The aim of published work was to develop and apply an appropriate methodology for plastics pyrolysis products evaluation and characterization using flash micro pyrolysis unit connected with GC-MS analytical device. At the same time study of production of fuel fraction in dependence on reaction condition was performed too.
Pyrolysis Technology Review
The article provides a basic overview of pyrolysis technologies, which are used for thermal processing of coal, biomass and waste on an industrial scale. The technologies are different in the type of pyrolysed raw material (coal, different types of biomass, solid municipal waste, sewage sludge, etc.), in the process conditions (pyrolysis temperature, the residence time of the products in the reactor, drainage of pyrolysis products) or in the construction of the pyrolysis reactor (type, method of heating).
Upflow and Downflow Mode in laboratory Fixed Bed Reactors
Paper deals the possible regimes of testing HDS catalysts in laboratory reactors. There are used fixed bed reactors with two feeding methods of raw materials through reactor. The aim of this paper is to compare the advantages and disadvantages of reactor setups in Up-flow & Down-flow mode. Research institute of inorganic chemistry disposes with testing facility, which allows both ways of reactor operations.
Comparison of raw materials and products from hydrotreating of straight run gas oil and light cycle
This paper deals with comparison of composition and properties of raw materials and products from hydrotreating of light cycle oil (LCO) and straight run gas oil (SRGO). Both feedstocks were hydrotreated in a laboratory trickle-bed reactor using a commercial CoMo/Al2O3 catalyst. Diaromatics content in LCO decreased from 58 wt% to 11 wt% as a consequence of their conversion mainly to monoaromatics (increase by 48 wt%). Hydrogenation of monoaromatics to saturates took place in smaller extent (increase by 9 wt%). An appreciable decrease of LCO polyaromatics and polar compounds was observed. LCO density was lowered by 37 kg·m3 and its cetane index was improved from 19 to 26 as a consequence of change in its group composition. In LCO, 75 wt% of sulfur was bounded in benzothiophenes and 20 wt% in dibenzothiophenes. In SRGO, a significant part of sulfur was bounded in nonthiophenic compounds, only 35 wt% in benzothiophenes and 15 wt% in dibenzothiophenes. It was found that sulfur bounded dibenzothiophenes with alkyl groups in the 4 and 6 positions prevailed in the deep hydrorefined LCO and SRGO.
Separation of CO2 from biogas by adsorption at higher pressures
Biogas produced in biogas stations is mostly used in cogeneration units for the production of electrical energy. At the same time the heat produced, however, often discharges into the ambient air, leading to high energy losses; the total efficiency of energy use in a biogas plant is therefore low and usually does not exceed 40 %. For this reason, technologies for the biogas upgrading to the biomethan are being developed. Such modified biogas containing methane in the concentration higher than 95 % can be used as fuel for vehicles, or may be injected to the local gas distribution network. This article is aimed at the testing of the adsorption method that is one of the methods successfully used for the separation of carbon dioxide from biogas in operational practice. The testing of the different adsorbents for the separation of CO2 from the model gas mixtures in the laboratory conditions and further testing of the same adsorbents using real biogas produced at the Central waste water treatment plant in Prague Bubeneč is described.