The article presents the directions of foundry waste management, mainly used for spent foundry sands (SFS) and dust after the reclamation of this waste. An important aspect of environmental protection in foundry production is the reduction of the amount of generated waste as a result of SFS regeneration. The advantage is the reuse of waste, which reduces the costs of raw materials purchase and environmental fees for landfilling. Non -recycled spent foundry sands can be used in other industries. SFS is most often used in road and construction industries as well as inert material in closed mines (Smoluchowska and Zgut 2005; Bany-Kowalska 2006). An interesting direction of using SFS is its application in gardening and agriculture. The article presents the advantages and disadvantages of such use. It was found that spent foundry sands can be useful for the production of soil mixtures for many agricultural and horticultural applications. Due to the possibility of environmental pollution with heavy metals and organic compounds, such an application is recommended for the so-called green sands, i.e. SFS with mineral binders. In addition, an innovative solution for the energy use of dusts after spent foundry sands reclamation with organic binders has been discussed and proposed by some researchers. It was shown that dust from reclaimed SFS with organic binders can be used as an alternative fuel and raw material in cement kilns, due to the high percentage of organic substances which determine their calorific value and silica.
The article discusses the problem of the supply of a by-product, which is synthetic gypsum produced as a result of flue gas desulphurization in conventional power plants. The state of production and forecast for the future are presented. Currently, synthetic gypsum is almost entirely used as a raw material in the gypsum products plant located in the immediate vicinity of the power plant. Since the mid-1990s, in Poland, an increase in the production of synthetic gypsum associated with the construction of a flue gas desulphurization installation in Polish conventional power plants has been observed. In the near future, the upward trend will continue in connection with the construction of new coal units in power plants. Significant surpluses of this raw material will appear on the market, which will not be used on an ongoing basis in the production of gypsum components. However, due to the EU’s restrictive policy towards energy based on coal and lignite, within the next few decades, the share of conventional power plants in energy production will be gradually reduced. As a consequence, the supply of synthetic gypsum will also gradually decrease. Therefore, it is advisable to properly store the surplus of this raw material so that it can be used in the future. Taking this into account, it is already necessary to prepare methods for storing the expected surpluses of synthetic gypsum. For this purpose, post-mining open pits are particularly suitable, especially in mines of rock raw materials. The article proposes a legal path enabling the post-mining open pits to be transformed into a anthropogenic gypsum deposit.
One of the purposes of the application of chemically modified inorganic binders is to improve knocking out properties and the related reclamability with previously used in foundry inorganic binder (water glass), which allowing the use of ecological binders for casting nonferrous metals. Good knocking out properties of the sands is directly related to the waste sands reclamability, which is a necessary condition of effective waste management. Reclamation of moulding and core sands is a fundamental and effective way to manage waste on site at the foundry, in accordance with the Environmental Guidelines. Therefore, studies of reclamation of waste moulding and core sands with new types of inorganic binders (developed within the framework of the project) were carried out. These studies allowed to determine the degree of recovery of useful, material, what the reclaimed sand is, and the degree of its use in the production process. The article presents these results of investigation. They are a part of broader research programme executed under the project POIG.01.01.02-00- 015/09 "Advanced materials and technologies".
In the process of extraction and enrichment of coal waste, considerable quantities of waste material are produced, mainly the gangue and coal sludge, considered as waste or raw material. The main directions of the management development of the waste rock are the production of aggregates, the production of energy products and the liquidation works in hard coal mines and the filling of excavations. The paper proposes the extension of these activities to the use of waste material. The possibility of using aggregates or extractive waste to fill open-pit excavations has been proposed, also in areas within the reach of groundwater and the possibility of building insulation layers of waste material and the production of mixtures of hard coal sludge and sewage sludge to produce material with good energy properties. The analysis was based on the author’s own research and literature data related to selected parameters of waste material. This paper presents our own preliminary studies on the amount of combustion heat and the calorific value of coal sludge combined with other wastes such as sewage sludge. The proposed methods and actions are part of the current directions of development, but they allow the extension of the scope of use of both extractive waste and products produced on the basis of gangue or coal sludge. Due to the frequent lack of the stable composition of these materials, their current properties should be assessed each time before attempting to use them. The fact that it is important to continue research to promote existing economic use and to seek new activities or methods has been concluded.
This paper presents the results of research which is part of studies carried out under the project POIG.01.01.02-00-015/09 "Advanced Materials and Technologies", one of the aims of which is to introduce new, environment-friendly, inorganic binders to the production of castings from non-ferrous metals. The paper presents the results of research on the management of waste moulding sands prepared according to the new technology, including their multiple reclamation and management of post-reclamation waste. Studies of multiple reclamation are a continuation of the preliminary research described earlier. The programme of the studies described in this paper also included validation of the results under industrial conditions.