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Apart form main product output, the side products having the second raw materials and industry wastes status are being created in metallurgy plant technological process. Dust outlets, waste gases, technological liquids and particularly slags represent main metallurgy industry wastes. Metallurgy plant with closed production cycle and annual capacity of 5 millions tons of steel yearly produces about 1 million tons of blast furnace slag, 0.5 million tons of steelmaking slag and 0.05 million ton of secondary metallurg...

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 ...

Biosorption of Cd(II) ions from aqueous solu tions has been studied and determined to adsorption capacity. The expe rimental data obtained from batch equilibrium tests have been analyzed by three two-parameter (Fre undlich, Langmuir and Temkin) isotherm models, four three-parameter (Redlich-Peterson, Sips, Toth and Khan) isotherm models and kinetic models including the pseudo-f irst order and pseudo-second order. The adsorption data fit well with Temkin isotherm for orange peel and Freundlich isotherm for walnut a...

The production of pulps and paper has a variety of negative influence on the environment. There are some technologies which can moderate the negative impacts and they have also a positive economical ef fect (e.g. paper recycling). It causes the paper alterations, which results in the degr adation of their physical and mechanical properties. The recycling causes a chemi cal, thermal, biologi cal and mechanical destruction, or their combination. The aim of this work was to investigate changes of macromolecular weigh...

The paper presents the results of column adsorption of Cu 2+ metal ions from synthetic solution (concentration up to 200 mg dm -3) onto beech sawdust and wheat straw. Adsorption ability of the chosen type of adso rbent is considered as a function of the initial pH of solution. The breakthrough curv es are presented as a function of the aqueous phase volume passed through the colu mn allowing getting an insight in the column adsorption features. A very high adsorption degree – higher than 99% was achieved in thes...

The main emphasis of the research is on the utilization of plastic wastes and there are described findings from production and applic ation of synthetic aggregate made from waste polyethylentereftalate (PET), replacem ent of natural aggregate with PET grit, production of lightweight concrete with melamine and production of modern composite materials utilizing bonding compounds based on P ET. The study describes results from the research of application of suitable treated PET beverage bottles for the production of ...

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’...

Recycling is the method used to reduce the environmental impact of large volumes of materials, the sparing use of resources is another relevant factor here. The waste materials which occur in the foundry and st eel industry alongside the target products most be used elsewhere or returned to the foundry and steelmaking processes. The result will be that the need to dispose of material s will be greatly reduced , so alleviating the demand for landfill capacity. In addition, raw material depo sits will be conserved a...

The goal of a recycled paper or board manufacturer is to make a product that meets customersО„ specification and requirements. At the present utilization rate, using recycled fibres in commodity grades such as newsprint and packaging paper and board has not caused noticeable deterioration in product quality and performance. The expected increase in recovery rates of used pa per products will require a considerable consumption increase of recycled fibres in higher quality grades such as office paper and magazine pa...

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 paper presents some results of research and development, obtained by the institute and its partners, to promoting advanced technologies and equipment for wood waste recycling, in order to obtain the ecological compost used for developing a sustainable and ecological agriculture. At the beginning, there is presented mobile wood chipper equipment, for fragmentation and shredding of wood branch es resulting from activities of grooming / trimming of trees and shrubs in agricultural areas, orchards and forestry. In...

Castings production from gray cast iron is 55% of castings production around the world. Cupola furnace is the most used melting furn ace for the cast iron production. There is a counter current heat excha nge during melting process in the cupola furnace. Gases proceed upwards and charge and coke downw ards where they are heated. During this process the emission creation. These emissions come from coke and metallic parts of the charge. Another sources of contamination are particles created by abrasion of charge on ...

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...

The foundry industry, itself, is one of the wo rldВґs first recyclers. Foundries have been making new metal objects by remelting old ones. An estimated 15 to 20 million tons of scrap metal that would otherwise be sent to overcrowded landfills are being remade into new castings each year. As with most industries, the foundry industry generates its own by-products. Typical by-product streams from the foundry indus try include foundry sand, foundry slag, baghouse dust, and furnace and ladle refractory. In order to co...