Waste plastics make up approximately 20% of the volume of landifill material and almost 10% of the weight. These products contain substantial energy recovery value, and also represent a potentia!iy valuable source of feedstock raw material for additional plastics production. Controlled pyrolysis offers a method of converting raw, mixed waste plastics back into feedstock grade liquids by the application of heat in the absence of oxygen. However, chlorine from the thermal degradation of polyvinyl chloride (PVC) can contaminate the reclamed liquids making them more difficult and expensive for processing, and also produce a corrosive atmosphere which makes processing more expresive. This paper reports on a study of the impact of PVC on the thermal degradation rates other plastics including polypropylene (PP), polystyrene (PS), low-density polyethylene (LDPE), high-density polyethylene (HDPE) and polyethylene terephthalate (PET) in a thermogravimetric analyzer (TGA). Commodity plastics were mixed at various ratios with PVC and analyzed by means of their degradation rates to determine the kinetic rate constants which were compared to the rates obtained for the pure plastics. The values of the kinetic parameters for the pure compounds were all very close to, or within the ranges obtained from the literature. The results indicated that the decomposition behavior of the mixtures differed from those of the pure polymers. These deviations were greatest for mixtures of PVC with polyethylene terephthalate where it was determined that the dehydrochlorination step of PVC catalyzes the decomposition of PET. Pyrolysis of mixtures of PVC and polysteryne at temperatures between 200° C and 350° C result in incomplete dehydrochlorination. This results in more chlorinated compounds being released at higher temperatures.

The definition of environmental engineering and its goals as a technical scientific discipline are given in the study. Against this background the importance of momentum, heat and mass transfer processes in further development of this scientific field is mentioned.

Analysis of lead and cadmium concentrations in the air comparing concentration values difference between heating and summer seasons was carried out in the paper. Relevant procedure was adopted to find out if the concentration values in these two seasons differed in kind. The concentration seasonal difference was not found in case of cadmium but it was found for lead. It was proved in further part of the paper that the analysed mean 24-hour Pb concentrations for heating season could be presented as a sum of the mean annual background concentration and the concentration values resulted from Pb emission from sources active only in the heating season. In the area where the measurements were carried out residential furnaces were this kind of sources. The cumulative distribution function of the mean 24-hour lead concentration resulted from Pb emissions in the heating season was determined using two-layer neural network. It was found according to this approach that Pb concentration as the result of Pb emissions from residential furnaces, for 145 days, i.e. 80% of the heating season period, were at least two-fold lower than the lead concentration values as the result of Pb emission from the all year active sources. Only for 14 days emission sources active in the heating season produced Pb concentrations higher than Pb mean annual background concentration.

Model for simulation of reburning process was built using FLUENT computer code. The work was performed in two steps. At the beginning simplified chemical reaction scheme without reburning was applied in order to describe character of the process in the reactor. In the second step nine chemical reactions describing reburning process were selected. In both cases pressure fluctuations in reaction region were generated causing process intensification. Despite of the assumed simplification, good agreement of simulation and experimental results was acquired. Obtained spatial flow patterns, propagation of reactants and rates of chemical reaction allow for rational and effective modifications of the investigated process.

In 1995- 1997 and 1998-1999 floristical investigations were carried out within the projected ,,Dolina Sztoły" Landscape Protected Area, located in the Olkusz district (north-eastern part of the Silesian Upland). The occurrence of 413 taxa of vascular plants was reported. Out of 23 legally protected species, 16 are strictly and 7 are partly protected. Among vascular plants there are 28 regionally rare and endangered taxa, Medicinal materials used in Polish oflicinal medicine can be derived from 46 species. Eleven species (2,6% of vascular flora) represent mountain element. The richest group are hemicryptophytes (49,4%), while woody chamaephytes are represented by 3,4% of species.

Field measurements of the near-ground odorant concentrations were made in surrounding of the mechanical sewage treatment plant with separated digestive chamber. The concentrations downwind the pollutants plume in several different meteorological situations were the basis for the estimations by a process of trial and error. The estimations encompassed the total emission of odorants and emission rates related to the volume of the purified sewage, to the amount of the removed pollutants and to the area of the unorganized emission sources during the autumn. Parallel research concerning other seasons and different surface sources of odorants are planned.

The results of first investigation (from the formation in 1939) Gliwice Channel of polycyclic hydrocarbons concentration in bottom sediments was given. PAHs is a very important element of pollution for point of view of bottom deposits utilisation. From the Gliwice Harbour during the channel concentrations of PAHs are reduce. The most polluted is section of first 10 km. The highest concentration (7528 μgfkg) was determined in the bottom sediments of Kłodnica River, on the water intake to the channel. The smallest concentration was determined on the section from 19 to 28.9 km of channel (175 to 700 μg/kg ). The section from chemical factory Blachownia to Kozie Harbour has concentrations 946.88 μgfkg to 2254.915 μgfkg. During the every flood-gate-sections the PAHs concentrations were increased. The hydraulic conditions are the agent determining the distribution of PAHs by influent on the organic suspended solids sedimentation.

This paper summarized results of estimation of concentrations of pollutants (chemical and bacteriological) in a barrier lake on the river Łęg (Wilcza Wola near Raniżów, subkarpatian province). The second goal of the research was aimed at a trial of forecasting the pollution of apparently stagnant water (as the test bed the barrier lake mentioned was used) applying pattern recognition method in a variant called ,,look-ahead-and-back-KNN" [8, 9]. It was found, that concentrations of some contaminating species can be predicted with satisfactory accuracy. The approach tested allows to develop a dense grid, partly consisting of nodes with real (experimentally estimated) results, and partly consisting of nodes with these values predicted. Additionally, our research has been recently augmented with results achieved using data mining methodology based on virtual visualization [12].