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Further to the global trend of using wastes as secondary resources, also in the Czech and Slovak Republic there is an emphasis on the new benefication of wastes in terms of their further utilization and recycling in technological processes. The utilization of wastes does not only broaden the raw material base, but it also helps to save the primary sources of minerals as well as there are lower costs of waste transport, dumping and disposal thanks to their complex utilization. The paper deals with the application o...

The paper deals with the issue of separating biodegradable PLA (polylactic acid) bottles from conventionally used packaging materials such as PET (polyethylene terephthalate). The separation of these materials is especially important because each of the plastics has a different cycle at the end of its secondary use. Recycling PET bottles the quality of the granulate may be degraded due to the occurrence of PLA material, while the occurrence of PET is undesirable during composting the biodegradable plastics PLA as ...

Waste management is pressing harder with the alarming signal warning the industry. The success of local recycling programmes is reliant upon households’ participation. Recycling of solid wastes is considered as the only method to recover the waste generated. In recognition of this, doorstepping approach is used as one the main driver tools towards increasing households partic ipation. This study was based on selected residential areas (different level incomes) within Kuala Terengganu town (Malaysia). Questionnai...

Recovery of gold and other valuable metals from electronic scrap involves a complex metallurgical flow sheet and requires state- of-the-art recovery technologies that are available in large-scal e, integrated smelter-refinery opera tions. At the end of their use, electronic and other el ectrical product scrap offer an important recycling potential for the secondary supply of gold and silver into the market. With gold concentrations reaching 200-250 g/t for computer circuit boards, this scrap is an ‘urban mine’...

The paper presents the main factories which determine the environment pollution at hot dip galvanization process of steel sheet and developing of recycling technologies of zinc by-product, with a view to recovering metal zinc or different sub- products, and returning them in the production cycle. By th e recycling of zinc by- products the prime material consumption is reduced and enviro nmental protection is improved. Industrial wastes generated in the hot dip galvanization pr ocess of steel sheet are: zinc ash, d...

In the world, over 18 million vehicles are rejected annually from operation. The spent catalysts are obtained from th e vehicles at the end of their life cycle as well as the vehicles which do not meet the prescribed st andards in the ECO test respected to the composition of exhaust gases. The basis of each catalyst is a ceramic monolith with deposited valuable platinum metals. The spent catalysts are solid waste and also the rich raw material for recovery of precious metals. The aim of this paper is a separation ...

Zinc is a widely applicable metal and therefore the different composition and form of zinc waste is generated. The most important waste material generated in production and processing of zinc is scrap metal of zinc and its alloys, as well as slag, dust and sludge from the production and processing of cat hode zinc and zinc alloys. In terms of processing technology, there are different app lied procedures depending on the type of raw material. The processing of waste zinc a nd its alloys is pyrome tallurgical and i...

The power plants produces hundreds tones of fly ashes yearly. From this amount is really used in the reason only 10 % with out the any treatment in the industrial production. The rest of this ashes are de posited on dumps and settling pits, that have many negative influence on the environment. Following the previous results from the extensive treatment research was proposed the waste less technology of the complex treatment and utilization of black coal fly ash. The final products of this technology are the produc...

It is proposed to process gold mine man-made wastes through ultrasonic activation of source materials in water, then in an alkaline solution with subsequent cyanidation of gold-impregnated cakes, or direct cyan idation and sorption conditioning of gold multicomponent solutions with nano-structured anionite an av erage radius of pores of which is within 600-700 Зє that contains no more than 6-8% of strong-base groups. A preliminary withdrawal of elements accompanying gold ensures obtaining of good- quality target m...