Jana Müllerová

Emission Distribution and Regulation of Local Heat Source

Pollutants can be classified according to their chemical composition, harmfulness, hazardousness, risk rate and toxicity. The most monitored pollutants are particulate matter (PM), carbon monoxide (CO), nitrogen oxide (NOx), sulfur dioxide (SO2), organic substances which are in the form of gaseous phase in waste gases expressed as total organic carbon, dibenzodioxins and dibenzofurans [1-3]. Other pollutants are divided into several groups and subgroups, such as substances with carcinogenic effects (asbestos, Co, Cd, Be, Ni, As, Cr, dioxins, etc.), solid inorganic contaminants (He, Se, animony, and others) and inorganic pollutants in the form of gases (HCl, HF, ammonia, etc.), organic gases and vapours (phenol, toluene, acetone and many others) and gases causing the greenhouse effect (CO2, methane, N2O, hydrofluorocarbons, etc.). The term particulate matter, or suspended matter refers to the emissions of a wide range of wind drift solids and liquid particles of material in size from several nanometres up to 0.5 mm, which stay in the air for some time. This is a major component of atmospheric pollution, which contributes to harmful effects not only on human health but also on intensity of materials degradation. Into the atmosphere, where we can meet them, regardless of particle size and chemical composition, in the form of a complex heterogeneous mixture, they are released from burning fossil fuels and also from burning biomass-based fuels, while domestic heating accounts for about 16% of the total production of particulate matter [4,5,6]. This percentage represents a degree of imperfect combustion of fuels used in local heating. Emissions from incomplete combustion are undesirable from the point of view of human health as well as from the economic point of view, because this leads to the degradation of materials. Nevertheless, since fuel combustion is necessary for the society, emissions are still produced. This paper presents an automated method of perfect combustion control in local heating in order to minimize emissions being produced.

A New Procedure for the Determination of the Main Technology Parameters of Rolling Mills

Nowadays, approximately 90–95 % of metals are processed by cold rolling. There has been a substantial increase in demand for utility properties as well as for reducing production costs. These objectives cannot be achieved without a high degree of automation, control and monitoring throughout the manufacturing process. These qualitative changes require rather deep and comprehensive theoretical and metallurgical–technological knowledge of operators in the field of design, research and production of rolled steel sheets, which is needed for further development in rolling steel. A continuous quality control of material and surface during the rolling process is a part of these tasks and is associated with providing the full automation of rolling mills. Starting from theoretical foundations, we have developed a new procedure for the determination of main technology parameters of a rolling mill. The main difference between our proposal and current methods of calculation is as follows. Our proposal is based on the knowledge of deformation properties of materials and continuous processes of stress-deformation state and on the knowledge of reductions in different stages of rolling. Current procedures are on the contrary based on static calculations using the geometry of the system—working roll and instantaneous sheet metal thickness in a gap between the rollers. In doing so, the calculations almost ignore the real stress—deformation properties of rolled metal sheets, optimal transmission rate of deformation in the material at the given speeds of rollers and the given main rolling force. We are concerned with the optimum balanced system: main rolling force—rolling speeds, or transmission rate of deformation in the material. This procedure allows us to achieve a significant increase in operational performance as well as in rolling process quality.

A New Approach to Surface Tension According to the Surface Topographical Features in Laser Cutting Technology

Laser - cut quality is mainly characterized by a degree of accuracy in shape, size and also by surface layer conditions after cutting associated with surface roughness. An experimental determination of surface tension (or tensor components) of clean metal surfaces is very difficult and there is no direct method for its measurement. Attention was paid to numerical derivation of surface tensions according to the surface topographical features in laser cutting technology. The surface tensions and temperature dependencies of several metallic materials have been determined and confirmed by data obtained from the literature. It was found to be in very good agreement between our results and data from different sources in the literature.

Modifications of Pyrolysis Boilers to Reduce Harmful Flue Gas Emissions

In addition to emission level reduction, combustion process optimization by modifications of pyrolysis boilers is aimed at fuel cost decrease. Knowledge of fuel composition and fuel combustion properties is important to the optimum and economical combustion process. The levels of emissions caused by the process can be reduced by several designs and operational modifications. This paper deals with modifications of combustion equipment in order to reduce harmful flue gas emissions in a boiler MA 23. The hot water boiler MA 23 belongs to gasification boilers for dry lump wood combustion; it is intended primarily for the heating of family houses, cottages, small office buildings and other small buildings and has the maximum required heat output of 23 kW. The boiler was tested in several modes, based on the requirements of the standard EN 303-5 dealing with emission limits. A basic requirement was the implementation of technical measures described in the paper and a proposal of method of regulation of flue gas volumetric flow rate and of installation in order to keep emission levels below the required limit.

Comparison of Performance and Emission Parameters in Two Developmental Stages of Boilers

To meet the high demands of customers for low temperature boilers, a semi-automatic boiler MAGA PU 25 was developed. One of the main customer requirements is to get the best price-quality ratio. Another very important requirement is to meet emission standards. At the time of development of the boiler PU 25, the European standard STN EN 303-5 was valid in Slovakia. Because this boiler did not satisfy the strictest performance criteria, a new type of the boiler, i.e. boiler MAGA P 20, was designed; as a result of design modifications, this boiler fulfils these criteria. The article compares the designs and the results of testing both the boilers using a test fuel in an accredited laboratory. The article deals with testing a new biomass boiler developed to satisfy the highest safety and emission criteria. It presents the comparison of two boilers, namely the standard biomass boiler PU 20 and the latest P 20 version with specific design modifications. Laboratory tests have shown an increase in combustion efficiency to the desired level.

Infrared Monitoring of Inner Defects in Glass Laminates

In this paper, we present some distinguished methods of the digital thermograms software treatment which allows the visualization of hidden defects in glass fabric laminates, which are not usually visible in standard raw thermograms. The results of the software treatment are tested on artificial defects in glass laminate plates.