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Construction and demolition waste (C&D waste) is one of the most relevant waste types primarily due to large quantities and a high potential for re-use and recycle. This paper discusses the issues related to C&D waste management in the Republic of Croatia. It presents the overview of legislative changes and its impact on the C&D waste management in Croatia. C&D waste quantities per county in the period from 2001 to 2015 are given as well as the expected C&D waste quantities in the future. It is concluded that the legal framework is well established, but it is not implemented consistently. Therefore, it is necessary to plan certain activities and additional resources in order to make the C&D waste management more efficient. The paper also presents the options of C&D waste recycling and describes the recycling technology in a C&D waste recycling plant in the Republic of Croatia. Taking into account the relatively low price of recycled aggregate, long distance transport is not profitable. It is concluded that the use of mobile treatment facilities would be a good practical solution taking into account the underdeveloped infrastructure for C&D waste management.

Waste electric and electronic equipment (WEEE) has the fastest growth compared to other types of waste due to the amount and thus increasing the need for its care about it. Disposal at landfills is not desired by the fact that this type of waste contains a number of useful materials that can be used again, as well as dangerous substances for which disposal is not desirable. This paper presents laboratory tests of separating copper from telephone (UTP and STP) cables that are an integral part of electronic equipment. Testing were carried out by method of gravity concentration using Wilfley shaking table and Humphreys spiral concentrator. The results showed that these devices can be used successfully to obtain copper concentrate whereby better results were obtained at a shaking table., Zużyty sprzęt elektryczny i elektroniczny (WEEE) to najszybciej rosnący strumień odpadów w porównaniu do innych rodzajów odpadów, a tym samym powstaje zapotrzebowanie na jego skuteczne zarządzanie. Unieszkodliwianie odpadów na składowiskach odpadów nie jest pożądane z uwagi na to, że ten rodzaj odpadów zawiera wiele użytecznych materiałów, które można wykorzystać ponownie, a także substancje niebezpieczne, których składowanie wymaga spełniania rygorystycznych wymagań. W artykule przedstawiono wyniki badań laboratoryjnych separacji miedzi z kabli telefonicznych (UTP i STP), które stanowią integralną część sprzętu elektronicznego. Separację przeprowadzono metodą wzbogacania grawitacyjnego na stole wytrząsającego Wilfley i Humphreys oraz separatorze spiralnym. Uzyskane wyniki wykazały, że te urządzenia mogą być z powodzeniem stosowane do uzyskania koncentratu miedzi.

Bentonite has vide variety of uses. Sepecial use of bentonite, where its absorbing properties are employed to provide water-tight sealing is for an underground repository in granites. In this paper, bentonite processing and beneficiation are described.

Soil cleaning technologies are becoming more and more important especially in industrialized countries. Application of soil washing i.e. physical separation results in cleaned soil which can be reused at the origin or the other location. Separated impurities (metals, hydrocarbons) are considered as special waste and further processed and/or disposed on special landfills. Technologies that were originally developed for mineral processing, due to similarity of operative goals – concentration/separation of certain matter adhering to a certain class of grain collective – have a high potential for use in soil cleaning. The purpose of this paper is to give a review of mineral processing methods which can be applied in soil washing technology, and to present some of the processes successfully applied in practice.

Froth flotation is a process for separation fine solids based on differences of surface characteristics of mineral particles. Separation by flotation is a result of interaction of many variables. The recovery and selectivity depends not only on chemical variables, but also on hydrodynamics of flotation. Hydrodynamics condition in mechanical flotation cell is more turbulent than in flotation column. The paper present results obtained during initial breaking-in of laboratory flotation column on fine coal samples. Optimal dosage value of AF2 collector used in testing was approximately 700 g/t. The best results were obtained by pulp density in range from 50 to 100 g/l. Also, aeration rate should be in range from 24 to 30 l/h. Test with different bubbles sizes showed better result with smaller bubbles.

Demand for metals continuously increases so that metal collection and recycling of waste containing metal become very profitable. Firstly, it refers to steel, copper, aluminium, lead, zinc and their alloys. These metals can be collected selectively (aluminium and steel tins), collected as refuse products (old cars, household appliances, electronic waste) or mixed with other materials (municipal waste). Selectively collected metal does not contain other material impurities and it is compacted (baled) and sold as a metal. Waste which contains other materials besides metal has to be recycled. The recycling process usually includes comminution, classification and separation. Crushers and mills are used for comminution, screens for classification and magnetic separators for metal separation. There are two main types of a magnetic separators: separators with slow rotation speed (drum and belt separators) and separators with high rotation speed (eddy-current separators). The former are used for the separation of magnetic materials (steel, iron) and the latter for the separation of nonmagnetic materials (aluminium, copper, lead, etc.). The paper describes the working principle, application and efficiency of magnetic separators in the recycling of various waste.

Silica sand is an important non-metallic mineral raw material within the resources of the Republic of Croatia. Croatian silica sand reserves could meet industrial needs over the long term. The 15 exploitation fields are registered, and the average annual production in the last 10 years is about 240, 000 tonnes. Depending on quality i.e. specific physical and chemical properties (grain size distribution, chemical and mineral composition, moisture content, etc.), silica sand is used as the basic mineral raw material for many industrial applications. To meet defined chemical and physical specifications according to intended application, the raw sand often has to be subjected to extensive physical and chemical processing. The paper describes main beneficiation methods used in the processing of sand intended for industrial uses. Beneficiation procedure applied at the silica sand deposit "Jerovec" located in north-western Croatia is presented, as well as the results achieved under field conditions.

Glass recycling is the process of turning waste glass into usable products. Glass is an ideal material for recycling and in some cases can be used repeatedly without any deterioration in its physical properties. There are several types of glass entering the waste stream each with different chemical compositions and physical properties. Recycling of complex material such as a glass is a simple but hugely beneficial process which consists of several steps. The complete recycling loop can be repeated an infinite number of times and the quality of the glass will never deteriorate. The paper describes recycling cycle, recycling technology and overview of glass recycling state in EU.

Mining activity in the Republic of Croatia is based mainly on the exploitation and production of non-metallic mineral raw materials. Since carbonate rocks are predominant in the geological structure of Croatia, in the majority of quarries limestone and dolomite are exploited. Dolomite is widely used in various industries e.g. construction industry, building material industry, metallurgy, glass industry, etc. In glassmaking it is added to raw material mixture in the form of dolomite grits (- 1 mm) as one of the essential components for the input of glass modifiers that is CaO and MgO. To be used for this purpose, dolomite has to meet certain standard specifications established by the glass industry. In most cases, dolomite exploited in quarries does not satisfy demanding specifications and, therefore, its further processing is needed. The paper describes processing technology for dolomite intended for use as a raw material in container glass production. Fe2O3 content in exploited dolomite before beneficiation varies in range from 0.052% to 0.07%. By beneficiation procedure applying dry magnetic separation, dolomite grits with Fe2O3 content less than 0.05%, which meets the requirements of container glass industry, are obtained. The results presented in this paper are achieved under field conditions.

The non-metals and building materials industry accounted for approximately 8 % of the total industrial output in Croatia during year 2004. Nowadays more than 200 trading companies in Croatia deal with the exploitation of solid mineral raw materials, and almost 50 % of them exploit technical stone. In the majority of technical stone quarries, the deposits of carbonate rocks (limestone and dolomite) are exploited, whereas in only eight quarries the eruptive rocks are exploited. If raw material contain impurities, which necessitates wet processing operation, waste water must be cleaned before being let out of the processing plant or returned to the dressing process. In the paper the waste water treatment in technical stone quarry is presented.

The demand for secondary materials, primarly steel, glass and plastics, has led to the significant development and application of new techniques, equipments and plants used in recycling. The paper describes the basic techniques for solid waste comminution and presents the typical machines and equipment used for this purpose. The aim of the paper is to draw domestic industry's and contractor's attention to the production area which in spite of certain production potentials still doesn't exist in Croatia.

The Croatian non-metals industry comprises exploration, exploitation and processing of non-metallic mineral raw materials. By beneficiation of these rock standard stone sizes for the production of concrete, asphalt masses, of supporting layers in road works and railroad ballast were obtained. In most technical stone quarries, rock deposits of a carbonaceous structure are exploited, whereas just some few quarries are exploiting rock deposits of a siliceous structure. An overview of eruptive technical stone production in the Republic of Croatia is given in this paper. The technology of stone exploitation and dressing are shown on quarry Jelenje Vode.

The paper presents the results of attrition cleaning obtained by testing the samples of quartz sand under laboratory conditions. The tests were carried out in two types of laboratory attrition cell – with circular and octagonal cross section, at different values of operating parameters which are supposed to have the main influence upon the attrition efficiency: suspension density, attrition time and stirrer speed. In each type of attrition cell two series of tests were conducted on two quartz sand samples with different SiO2 i.e. impurity contents. Indicators of attrition efficiency were the content of the particles – 0.063 mm and content of main impurities (Al2O3, Fe2O3) removed through the attrition process. By comparing the results of both series of tests conducted in mentioned types of attrition cells, information on dependence of attrition efficiency on feed material composition, operating parameters and attrition cell construction were obtained.

The soil washing process is similar to one applied in mineral processing. In mineral processing the useful mineral component is separated from tailings, and in soil washing relatively small amount of highly contaminated concentrate is separated from the mass of cleaned soil. The washing process includes several stages: soil preparation (pre-screaning and possibly crushing), liberation and separation of individual components respectively, classification, sorting and dewatering. The paper describes the individual stages of washing as well as the most important machines which is used in the process. Personal expirience wtih the application of attrition and column flotation are mentioned.

Flotation is universal method to fine coal processing. Selectivity and efficiency of flotation depends not only on surface characteristics of particles, but also on hydrodynamic condition in flotation cell. The goal of the research was to compare flotation column and conventional mechanical flotation cell in coal flotation. The tests was carried out in both flotation cells in the same conditions. The results indicated that the mechanical cell has greater recovery, whereas the flotation column has a considerably better selectivity since it provides a concentrate of better quality.

The quality of quartz sand can be improved by reducing the oxide coatings on the quartz grains. In this direction, a study has been made to consider the possibility of coatings removal from quartz sand by attrition cleaning. Tests were conducted in a laboratory attrition cell at different values of operating parameters: suspension density, attrition time and stirrer speed. Indicators of attrition efficiency were the content of the particles – 0, 063 mm and content of main impurities (Al2O3, Fe2O3) removed through attrition process.

The greatest part of crushed stone, gravel and sand production is won by open pit operations, whereas gravel and sand partially also from river beds. Its obvious that such a mining activity provoke some changes in the configuration and environmental characteristics of the region, in the temporary or permament disapperance of vegetable or animal species and in the creation of noise, dust and waste water. However, mentioned mining operations shouldn't have only negative effects on the landscape and land potential, but they can discover and predetermine potential of exploited area for various communal purposes after exploitation (eg. sports and recreation centers, campsites, resorts, fish-farms, etc.). In this paper, construction aggregates production in plants located in the vicinity of Zagreb, the capital of Croatia are presented. Advantages and disadvantages of aggregates production in the urban area in the spirit of sustainable development are discused.

The quality of quartz sand can be improved by reducing the oxide coatings on the quartz grains. In this direction, a study has been made to consider the possibility of coatings removal from quartz sand by attrition cleaning. Tests were conducted in a laboratory attrition cell at different values of operating parameters: suspension density, attrition time and stirrer speed. Indicators of attritioning efficiency were the content of the particles - 0, 063 mm produced by abrasion of grain surfaces and content of main impurities (Al_2O_3, Fe_2O_3) removed through attrition process.

The production of technical stone, gravel and sand for the building industry is a very important part of the mining production regarding volume and the financial value as well. The most demanded classes are with grain sizes &#8211 ; 4 and &#8211 ; 2 mm but their production is not always simple. In addition to volume, the specific grain size composition, grain shape and minimal portion of the particles &#8211 ; 0, 09 mm (filler) usually are demanded. Until about ten years ago the portion of the impact and hammer crushers, less often cone crushers were used in the production of these classes. Nowadays the vertical impact crushers (rotor mills) are mainly applied for this purpose. In the paper are presented some of these crushers used in the quarries and gravel-pits in Croatia. Their efficiency (capacity, grain size composition, grain shape, filler portion) depending on the influence of the some technological parameters, as for example grain composition of the feed material, physical-mechanical rock properties, moisture content and etc. are analysed.

Wood is the main material for paper production and with high costs of raw material paper mills are searching for other materials for paper production. With a higher demand for paper, waste paper is being used more and more as the main material for paper production. To be able to use waste paper in paper production we must pulp it, remove all contaminants and deink. In paper recycling plants a huge problem is waste water due to the high water consumption. Waste water from paper recycling is treated in different ways then reused in the recycling process. Croatia’s waste paper recovery rate is one of the lowest in the European union and in 2010 was only 3,97 kg per person. Improving the recovery rate could be done by introducing new technologies in waste paper collection i.e. modern trucks for waste paper collection., Drvo je glavna sirovina za proizvodnju papira, te s visokim troškovima ulazne sirovine, tvornice papira su u potrazi za drugim materijalima za proizvodnju papira. S povećanjem potražnje papira, otpadni papir se sve više i više koristi kao glavna sirovina u proizvodnji novog papira. Kako bi se otpadni papir mogao koristiti u proizvodnji potrebno ga je provesti u pulpu te odstraniti sve nečistoće i tintu. Zbog velike potrošnje vode u postrojenjima za reciklažu papira veliki problem je otpadna voda. Ona se pročišćava na razne načine te se ponovno koristi u procesu recikliranja. Povrat otpadnog papira u Hrvatskoj je praktično na najnižoj razini u Europskoj Uniji, a 2010. godine iznosio je samo 3,97 kg po osobi. Unapređenje povrata starog papira moglo bi biti poboljšano uvođenjem novih tehnologija u prikupljanju otpadnog papira npr. suvremenijim kamionima za njegovo sakupljanje.