Search

At the present time, almost every area needs using of secondary raw material sources. This trend is most obvious in the industry, mainly in the area of materials production, when there is a possibility of economic effectiveness increasing during production. Also, the contribution of secondary raw material using is not negligible in the area of living environment protection, since it can use the waste of industrial production again. The task of this contribution is an economic evaluation of using a geopolymer from coal combustion as a possible alternative raw material. The basic input is the cost of materials for the manufacture of concrete using of Portland cement with fly ash as a substitute for cement and fly ash as an additive to concrete. Evaluation is carried out based on analysis of the possibilities to reduce the total price of material costs for the production of 1 m(3) of concrete, with possible using in the industry. The main method for economic evaluation of using geopolymer is the classical cost calculation. The results of the analysis show possible reducing of cost, which is possible through replacement of cement by fly ash more than 18 % of the material. Web of Science 21 2 145 139

Unconventional crude oil sources are geographically extensive and include the tar sands of the Province of Alberta in Canada, the heavy oil belt of the Orinoco region of Venezuela and the oil shales of the United States, Brazil, India and Malagasy. High production costs and low oil prices have hitherto inhibited the inclusion of unconventional oil resources in the world oil resource figures. In the last decade, developing production technologies, coupled with the higher market value of oil, convert large quantities of unconventional oil into an effective resource. From the aspect of quantity and technological and economic recoverability are actually the most important tar sands. Tar sands can be recovered via surface mining or in-situ collection techniques. This is an up-stream part of exploitation process. Again, this is more expensive than lifting conventional petroleum, but for example, Canada's Athabasca (Alberta) Tar Sands is one example of unconventional reserve that can be economically recoverable with the largest surface mining machinery on the waste landscape with important local but also global environmental impacts. The similar technology of up-stream process concerns oil shales. The downstream part process of solid unconventional oil is an energetically difficult process of separation and refining with important increasing of additive carbon production and increasing of final product costs. In the region of Central Europe is estimated the mean volume of 168 million barrels of technically recoverable oil and natural gas liquids situated in Ordovician and Silurian age shales in the Polish-Ukrainian Foredeep basin of Poland. Web of Science 21 3 257 247

Sintering process is a summary of physical, thermal, and physical-chemical processes taking place simultaneously in a given time interval, but in particular order within a time sequence. The input raw materials of the sintering process include a number of negative elements, which can later affect the course of the blast furnace process. The key point is to monitor the amount of these raw materials and purposefully try to reduce their amount. The article deals with the content analysis of selected harmful substances entering the sintering process in order to reduce their amount that later continues into the blast furnace process. Web of Science 54 4 652 649

Reserves of brown coal in the Czech Republic are, in the long term view, still recognized as the main domestic fuel and energy resource. The biggest issues, concerning the use of these domestic resources, are, according to the authors, the existence of the “Resolution of the Government of the Czech Republic No. 444” of 30 October, 1991 together with the new State Energy Concept, which was approved in May this year, and which states that the CR will export three out of four key fuels and energy resources, namely oil, gas and nuclear fuel. Brown coal is, therefore, the only domestic energy resource that allows a long-term guarantee leading towards reducing the energy dependence. Web of Science 20 4 310 298

The ability to optimize costs plays a key role in maintaining competitiveness of the company, because without detailed knowledge of costs, companies are not able to make the right decisions that will ensure their long-term growth. The aim of this article is to outline the problematic areas related to company costs and to contribute to a debate on the method used to determine the amount of fixed and variable costs, their monitoring and follow-up control. This article presents a potential use of regression analysis as an objective tool of economic management in metallurgical companies, as these companies have several specific features Web of Science 54 3 596 594

In July 2018, measures of the European Commission regarding the Circular Economy Package (CEP) came into force. All EU Member States have two years since to implement these measures into their national legislations. The aim of the authors is, using available resources, to evaluate current conditions in the Czech Republic in the areas affected by this legislation. It is primarily the area of waste management, which has set values within the CEP that must be achieved within those two years. The article offers an analysis of the circular economy penetration into the Czech legislation. The procedure for introducing changes in legislation is presented through the Waste Management Plan (WMP) for the period 2015-2024. The aim of the article is to verify whether whether the Czech Republic is able to meet the EU and WMP's requirements in the current development of waste management. The authors are first to use the analysis of secondary data from national and transnational sources, from which they created unique and original outcomes for the given issue. After the analysis, they introduced the measures that could be used for the greater motivation of the target groups in order to meet the goals of the Czech Republic. The authors address the concrete impacts of CEP implementation within the Czech Republic and also present Czech examples of good practice. Web of Science 24 4 375 366