Producing polytetrafluorethylene membranes and laminating them on textile backings

This paper discusses a variety of experiments related to the manufacturing of polytetrafluorethylene (PTFE) membranes and laminating them on textile backings. Due to the fact that the PTFE membrane production process is protected by international patent law, making the PTFE technology somewhat inaccessible ([6] and [7]), the author of this paper used innovative production processes and techniques to conduct the pilot PTFE membrane production experiments. In the field of PTFE membrane lamination, another step forward was made by patenting an innovative production process [5]

Theoretical and experimental foundations for the manufacturing of mechanical insulation foams

This paper deals with the theoretical conditions necessary for the formation of stable mechanical insulation foam. In addition to this it gives concrete proposals for the formation of mechanical foam and its application to surfaces in the field of civil engineering. Mechanical foam is formed relatively easily, provided suitable conditions are present. The insulating character is provided by finely distributed air bubbles in the insulation layer Similar characteristics can be found in various products made of foamed concrete as well as foamed polystyrene, which are not manufactured on site but in manufacturing plants. The main objective is the formation of a porous mechanical foam on the construction site and its application onto construction elements. The foam must be stable enough to be applied to the construction surface and then solidify

Measurement and modelling of process impacts of substrates and filter media to the operation of wastewater treatment plants with fixed biomass

Substrates and filter media are built in wastewater treatment plants in various ways, and can have a high impact on their operation effect. As such, they can either only intensify the treatment processes, or they can act as a main treatment carrier. The specific treatment effects, which can be achieved by substrates or filter media application, were until now rarely exploited in the wastewater treatment plants design. The usual reason for this was insufficient knowledge about these materials as well as the high costs of membrane filtration technology. Especially interesting are those technological solutions that use the biological treatment processes in a combination with various substrates and filter media. This can be also seen from the research results provided in this paper. The relatively easy removal of phosphorus and heavy metals from the wastewater, via suitable substrates, can, for example, take place in the percolators and constructed wetlands. It was found that some substrate types provide much more suitable conditions for the development of bacterial communities than others. If the membrane filter is included into the treatment process, then the treatment efficiency of the wastewater treatment plant can be significantly improved, although its size remains the same. Using these techniques, relatively easy removal of viruses, bacteria, and some heavy metals can also be achieved

Effective pre-treatment of dairy wastewaters\ud

Milk processing effluents typically present a considerable burden to the environemnt. The level of burden can be determined with the use of ATV (Allgemeine Technische Vertragsbedingungen), VDI (Verein Deutscher Ingenieure) and BAT (Best Available Techniques) standards, or via operational monitoring. Water emissions from dairy plants are associated with high water pollution costs. In our survey of dairy processing plants, we found water emissions in excess of ATV and BAT standard predictions. As dairy plants are usually connected to public sewer systems with centralized water treatment facilities, the economic viability of installing effective waste water pre-treatment plants is an important issue to examine. In Slovenia, dairy\ud plants pay water pollution fees and contribute to clean-up costs in centralized water treatment plants. This regime is similar to that in many other European countries. A preliminary test of the efficacy of flotation pretreatment\ud plants exhibited sufficient cleaning effects to reduce total anual burden by more than half. This level of cleaning efficiency could greatly lower the cost of water pollution. An investment in installing pretreatment\ud plants under such conditions would likely become cost-effective in a few years

Using porous ceramics as a substrate or filter media during the cleaning of sewage

Our research has shown that porous ceramics are good holders of biomass in biological water-treatment plants. They can also be used as an air-blowing system or as the filter media on a membrane filter in combination with a biological water-treatment plant. Individual tests have shown very positive results, and for this reason we are convinced such materials have good possibilities for more frequent use in biological water-treatment plants

Možnosti odstranjevanja ogljikovega dioksida iz zraka

Excessive atmospheric greenhouse gas concentrations currently represent an insolvable problem, as their quantities being emitted into the atmosphere far exceed the planet’s ability to extract them. In the realm of politics and the industry, management of this issue (eco-management) is being handled in what is a completely one-sided manner. The emphasis is almost entirely placed on ways to lower greenhouse gas emissions into the atmosphere, while the possibilities of extracting excess greenhouse gases from the atmosphere are being overlooked. As a consequence, resources are being predominantly devoted to the development of new technologies that generate lower greenhouse gas emissions. While these technologies can provide immediate relief, there is no reason to believe they are the most economically efficient options available. There are myriad new technologies in various stages of development that will be capable of extracting excess greenhouse gas emissions from the atmosphere, much like water treatment plants extract excess pollutants from water.Previsoka vsebnost toplogrednih plinov v zraku predstavlja trenutno nerešljiv problem, ker jih narava ni sposobna tako hitro odstranjevati iz ozračja, kot se v ozračje sproščajo. Upravljanje z okoljem (eko-management) na političnem in gospodarskem nivoju se ukvarja s tem vprašanjem povsem enostransko. Poudarek je skoraj izključno na tem, kako zmanjšati emisije toplogrednih plinov v ozračje, skoraj popolnoma pa je zanemarjen vidik odstranjevanja le-teh iz ozračja. Posledično se predvsem podpira razvoj novih tehnologij, pri katerih nastanejo bistveno manjše emisije toplogrednih plinov. To so trenutne rešitve, za katere pa ni nujno, da bodo v prihodnosti tudi ekonomsko najučinkovitejše. V razvoju so namreč nove tehnologije, ki bodo odstranjevale odvečno količino toplogrednih plinov iz zraka, podobno kot to počnejo čistilne naprave z onesnaževali v vodi

Postupci recikliranja tekstilnog otpada

U komunalnom okolišu i gospodarstvu svake godine nastaje velika količina tekstilnog otpada. Iako se taj otpad klasificira kao biorazgradljiv, takva klasifikacija nije odgovarajuća. Velik dio tekstilnog otpada je biološki slabo razgradljiv (sintetička vlakna, vuna, površinski obrađeni tekstilni materijali, vlaknima ojačani kompoziti itd.). Odlaganje tekstilnog otpada na deponije u posljednje je vrijeme ograničeno. Ako se tekstilni otpad spaljuje radi iskorištavanja topline, tada nastaju za okoliš opasni plinovi. Primjena takve tehnologije je moguća samo u dovoljno velikim postrojenjima za spaljivanje otpada, koja su opremljena učinkovitim napravama za čišćenje dimnih plinova. Stoga se preporučuje upotreba različitih postupaka reciklaže tekstilnog otpada, ovisno o vrsti otpada i proizvoda koje se želi proizvesti recikliranjem. Mogućnosti za upotrebu proizvoda od recikliranog tekstila su u građevinarstvu, automobilskoj industriji, poljoprivredi, obrtu, i sl

Recycling of textile wastewaters treated with various combinations of advanced oxidation processes (AOP)

Advanced oxidation processes (AOPs) are widely used for treatment of wastewaters containing recalcitrant\ud organic compounds from industrial and municipal wastewater; many advantages over other technologies\ud have been found and good treatment results have been obtained so far. Approaches which reduce fresh water\ud consumption are especially important for regions with shortage in fresh water resources and in high waterconsuming\ud industries. Within AOP4Water (a multinational project funded under the CORNET programme),\ud combinations of different AOP methods are being tested with the final aim to enable cost-efficient reuse of\ud AOP-treated effluents from textile industry. The key to wastewater reuse lies in increasing the efficiency of\ud AOP treatment that ensures the required water quality and decreasing operational costs. In the present study\ud a series of experiments was performed with real textile industry effluents using a single AOP method as well\ud as combinations. Following AOP treatments were applied: ozone (O3); O3+ UV irradiation (UV); O3 +\ud hydrogen peroxide (H2O2); and O3 + H2O2 + UV. The most effective combination for colour and COD\ud removal was O3 + H2O2 + UV with 75% - 86% of colour removal and 15% of COD removal

Effect of advanced oxidation processes (AOPs) on the biodegradability of municipal wastewater for its reuse in the textile industry

Reuse of treated municipal wastewater to supplement part of fresh water is becoming more and more\ud important. However, treated water can contain some pollutants that cannot be successfully removed with\ud classical biological wastewater treatment processes. Aim of the study presented was to assess whether\ud advanced oxidation processes (AOPs) and special enzymes enhance biodegradation of municipal wastewater\ud and if treated municipal wastewater can be reused in the production process of textile industry. To test\ud biodegradability we used a small-scale pilot wastewater treatment plant (PWWTP) consisting of six parallel\ud bioreactors with suspended activated sludge (CAS type). Bioreactors were supplied with untreated municipal\ud wastewater, AOP-treated municipal wastewater and AOP-treated municipal wastewater with addition of\ud special enzymes. The results showed that AOPs contributed to better biodegradation while enzymes did not.\ud Municipal wastewater treated by a combination of AOP and biological treatment was not suitable for reuse\ud in the dyeing process, but could potentially be reused in some other processes in the textile industry

Vpliv naprednih oksidacijskih procesov (AOPs) na biorazgradljivost komunalne odpadne\ud vode za njeno ponovno uporabo v tekstilni industriji

Reuse of treated municipal wastewater to supplement part of fresh water is becoming more and more\ud important. However, treated water can contain some pollutants that cannot be successfully removed with\ud classical biological wastewater treatment processes. Aim of the study presented was to assess whether\ud advanced oxidation processes (AOPs) and special enzymes enhance biodegradation of municipal wastewater\ud and if treated municipal wastewater can be reused in the production process of textile industry. To test\ud biodegradability we used a small-scale pilot wastewater treatment plant (PWWTP) consisting of six parallel\ud bioreactors with suspended activated sludge (CAS type). Bioreactors were supplied with untreated municipal\ud wastewater, AOP-treated municipal wastewater and AOP-treated municipal wastewater with addition of\ud special enzymes. The results showed that AOPs contributed to better biodegradation while enzymes did not.\ud Municipal wastewater treated by a combination of AOP and biological treatment was not suitable for reuse\ud in the dyeing process, but could potentially be reused in some other processes in the textile industry