Cyanobacterials (Cyanophyta) belong to phytoplancton. In normal stale concentration of cyanobacterial cells in water rangs between a few hundreds to a few thousands in I drn' of water but while blooming may be increased even to one million in I dm3. At this time water has characteristic color, depending on dominated species. Also characteristic smell is the results of the presence ofcyanobacterial and phytoplankton cells producing odour substances. The cyanobacterial blooms are very important hygienic problem for both human and animal health. While blooming they form foams and head coating on water surface. Also cyanobacterial toxins are huge problem. Cyanobacteria may produce acute toxins such as hepatotoxic peptides (microcystins, nodularins and cylindrospermopsin) and neurotoxic alkaloids (anatoxin-a, anatoxin-a(s), homoanatoxin and aphanotoxins). Cyanobacterial toxins are very dangerous substances which can intoxicate hepatocytes and the nervous system in humans and animals. In this situation it is very important to remove them effectively in water pretreatment processes. In the present paper have been presented for the first time in Poland data on removing cyanobacterial toxins from water in pretreatment process with application of chlorine dioxide and ozone on the example of Sulejów - Łódź water pipe system. In period I 998-200 I the effectiveness rnicrocystin-LR removal ranged between 74--92% while for other izoforms they were between 45-94%.

The production of biohydrogen from food waste (FW) by dark fermentation (DF) is a promising technology for commercialisation, as it is both a clean fuel and a suitable means of sustainable waste management. The described experiments compared the biohydrogen production yields obtained after the use of inoculum from two different sources: digested sludge from the wastewater treatment plant (WWTP) in Lodz and sludge from the anaerobic treatment of dairy industry wastewater (DIW) (unconcentrated and double-concentrated). In addition, the effect of different temperatures (70, 90 and 121°C) of inoculum pretreatment on the biohydrogen production in DF was tested. The process was carried out batchwise at 37°C. The highest yield of hydrogen production was obtained after the inoculum pretreatment at 70°C. In addition, a higher amount of hydrogen could be obtained by using sludge from the WWTP as the inoculum (96 cm3 H2/gTVSFW) than unthickened sludge from the DIW (85 cm ³ H ₂/g _TVSFW). However, after thickening the sludge from the dairy industry, and at the same time balancing the dry matter of both sludges, the hydrogen production potential was comparable for bothsludges (for the WWTP sludge – 96 and for the DIW sludge – 93 cm ³ H ₂/g _TVSFW). The kinetics of hydrogen production was described by modified Gompertz equation, which showed a good fit (determination coefficient R2 between 0.909 and 0.999) to the experimental data.

The paper projects the potential of agricultural waste Saraca indica leaf powder (SILP) in biosorbing chromium from aqueous system. The influence of pH, contact time, metal concentration, biomass dosage and particle size on the selectivity of the removal process was investigated. The maximum sorption efficiency of SILP for Cr(lll): 85.23% and Cr(VI): 89.67%was found to be pH dependent giving optimum sorption at pH 6.5 and 2.5 respectively. The adsorption process fitted well to both Freundlich and Langmuir isotherms. Morphological changes observed in Scanning Electron Micrographs ofmetal treated biomass confirm the existence of biosorption phenomenon. Fourier Transform Infra-red Spectrometry confirms that amino acid-Cr interactions contribute a significant role in the biosorption of chromium using target leafpowder. The successful applications of easily abundant agricultural waste SILP, as a biosorbent have potential for a low technological pretreatment step, prior to economically not viable high-tech chemical treatments for the removal of Cr from water bodies.

The parenchyma cellulose isolated from bagasse pith was used as an alternative resource for preparation of water-soluble cellouronic acid sodium salt (CAS). The influence of ultrasound treatment on the cellulose was investigated for obtaining CAS by regioselective oxidization using 4-acetamide-TEMPO and NaClO with NaClO2 as a primary oxidant in an aqueous buffer at pH 6.0. The yield, carboxylate content and polymerization degree (DP) of CAS were measured as a function of ultrasonic power, agitating time and cellulose consistency by an orthogonal test. The ultrasound-treated conditions were further improved by discussion of ultrasonic power, the most important factor influencing the yield and DP. An optimized CAS yield of 72.9% with DP value (DPv) of 212 was found when the ultrasonic strength is 550 W, agitating time is 3 h and cellulose consistency is 2.0%. The oxidation reactivity of cellulose was improved by ultrasonic irradiation, whereas no significant changes in crystallinity of cellulose were measured after ultrasonic treatment. Moreover, the ultrasound treatment has a greater effect on yielding CAS from parenchyma cellulose than from bagasse fibrous' one. The CAS was further characterized by Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM).

Poppet valves made from high-frequency heat-treated SUH3 steel have insufficient durability, and scratches appear on the valve face in prolonged use. It is necessary to develop surface treatment technology with excellent durability to prevent the deterioration of engine performance. Therefore, a surface treatment technology with higher abrasion resistance than existing processes was developed by direct metal deposition to the face where the cylinder and valve are closed. In this study, heat pretreatment and deposition tests were performed on three materials to find suitable powders. In the performance evaluation, the hardness, friction coefficient, and wear rate were measured. Direct metal deposition using Inconel 738 and Stellite 6 powders without heat pretreatment were experimentally verified to have excellent durability.

Nowadays, actions allowing for a reduction of anthropogenic mercury emission are taken worldwide. Great emphasis is placed on reducing mercury emission from the processes of energochemical coal conversion, mainly from the coal combustion processes. One of the methods which enable a reduction of anthropogenic mercury emission is the removal of mercury from coal before its conversion. It should be pointed out that mercury in hard coal may occur both in the organic and mineral matter. Therefore, a universal method should allow for the removal of mercury, combined in both ways, from coal. In the paper, a concept of the hybrid mercury removal process from hard coal was presented. The idea of the process is based on the combination of the coal cleaning process using wet or dry methods (first stage) and the thermal pretreatment process at a temperature in the range from 200 to 400 °C (second stage). In the first stage, a part of mercury occurring in the mineral matter is removed. In the second stage, a part of mercury occurring in the organic matter as well as in some inorganic constituents characterized by a relatively low temperature of mercury release is removed. Based on the results of the preliminary research, the effectiveness of the decrease in mercury content in coal in the hybrid process was estimated in the range from 36 to 75% with the average at the level of 58%. The effect of the decrease in mercury content in coal is much more significant when mercury content is referred to a low heating value of coal. So determined, the effectiveness was estimated in the range from 36 to 75% with the average at the level of 58%.

Pretreatment is aimed at making lignin structures, which in turn causes decrystallisation and depolymerisation of cellulose. This treatment allows to increase the energy potential of substrates. A properly selected method allows for obtaining larger amounts of biogas with a high content of biomethane. The aim of the study was to analyse selected pretreatment methods (ultrasonic and hydrothermal) for biogas yield, including biomethane, and to demonstrate the effectiveness of obtaining additional electricity and heat from these methods. It was based on the literature data. On basis the study, the following information was obtained: average yield of biogas and biomethane before and after treatment, difference in yield of biogas and biomethane after treatment, and the effect of treatment on the substrate used. Moreover, an estimate was made of the effectiveness of obtaining additional electricity and heat from selected pretreatment methods compared to hard coal. Based on the analysis of the ultrasonic treatment analysis, it was shown that the best result was obtained with the ultrasound treatment of the mixture of wheat straw and cattle manure with the following parameters: frequency 24 kHz, temperature 44.30°C, time 21.23 s. This allowed a 49% increase in biogas production. The use of pretreatment would therefore allow the production of more electricity and heat capable of replacing conventional heat sources such as coal.