Search

The bottom waste obtained from bio-mass burning shows a huge variability of chemical and physical properties, depending on the kind of bio-mass, the type of a cauldron and burning parameters. The huge variability of the bottom ashes from the incineration plant and co-combustion of bio-mass makes it difficult to find any way to its management. In reality, only the bottom ashes from coal combustion and the small amount from lignite combustion are used, mainly in the building industry and in mining industry. The article presents the initial research, concerning the estimation of the properties of the bottom ashes obtained from bio-mass congestion in the fluidized-bed boiler to use them safely for the environment. To determine the influence of the tested waste on plants, a number of pot experiments have been conducted. The plants which have been used are recommended for phytotoxicity estimation, and are also used for biological reclamation.

The cement industry has been using waste as a raw material for many years. Waste is also used as alternative fuel. Cement plants are an important element of the waste management system and fit the idea of a circular economy. When waste is recovered in the cement production process, direct and indirect CO2 emissions are partially avoided. This article discusses the cement industry in Poland. The current situation in terms of the use of alternative fuels and raw materials in Poland, the different types of waste and the amount of waste used is discussed. The article discusses changes in the amount of waste (the increase in the amount of waste used as raw materials from the year 2006 to the year 2019) and the types of waste recovered in the cement production process and the possibility of closing material cycles on the plant scale (recycling to the primary process - cement kiln dust) and industry (using waste from other industries: metallurgy - granulated blast furnace slag, iron bearings; energy production - fly ash, reagypsum/phosphogypsum, fluidized bed combustion fly ash, and fluidized bed combustion bottom ash; wastewater treatment plants - sewage sludge, etc.). The analysis shows that the role of cement plants in waste management and the circular economy in Poland is important. Industrial waste from metallurgy, power plants, heat and power plants, wastewater treatment plants, and municipal waste is used as the raw material for the cement industry, leading to an industrial symbiosis. [ABSTRACT FROM AUTHOR]

The alternative waste fuels have a significant share in the fuel mix of the cement industry in Poland. The conditions inside cement kilns are favorable enough for environmentally-friendly use of waste fuels. In the article, the authors discuss the current situation concerning the use of alternative fuels in Poland, from difficult beginning in the 1990s to the present time, different kinds of fuels, and the amounts of used fuels. The use of fuels in Poland is presented against the global and EU consumption (including Central European countries and companies). The increased use of waste-derived fuels, from the level of about 1% at the end of the 1990s to the present level of about 70%, allowed for the limitation of waste storage, including avoidance of greenhouse gas emissions and consumption of conventional energy sources; those effects also contributed to the implementation of the sustainable development and circular economy conceptions. The experiences of the cement plants worldwide prove that the use of waste fuels is ecological and economical. The examples showed in the article confirm that cement plants are greatly interested in using waste fuels from waste, as they invest in the infrastructure allowing to store bigger amounts of waste and dose them more efficiently. Thus, the cement industry has become an important element of the country's energy economy and waste management system. [ABSTRACT FROM AUTHOR]

The cement production process is associated with the emission of dust. These are mainly CKD (cement kiln dust) and BPD (by-pass dust), classified as wastes from group 10 -- Wastes from thermal processes, subgroups 10 and 13 -- wastes from manufacture of cement, lime and plaster and articles and products made from them. Cement kiln dust is a waste of variable composition and properties, which makes it a difficult material to recover. The main directions of recovery presented in the world literature indicate the use of dust from cement kilns in cement, mortar and concrete production, the production of bricks and in order to improve soil quality and wastewater treatment. Factors affecting chemical and phase compositions of dust from cement kilns are the reason why each waste should be analyzed individually. The paper presents the results of the analysis of the cement kiln dust after dedusting cement kilns and two bypass dusts. Analysis of the chemical composition has shown signi- ficant concentrations of chlorine, potassium and calcium in all wastes. The content of: Si, S, Ti, V, Cr, Mn, Fe, Ni, Cu, zn, zr, Pb, and Bi has also been confirmed. The analyzed dusts were characterized by the presence of carbonates (calcite, dolomite, and arcanite), quartz, alite, belite, sylvine, anhydrite, and portlandite in their phase composition. The leachates which were characterized by an alkaline reaction. In terms of leachability, high concentrations of chlorine ions in the analyzed dust leachates were confirmed, which significantly limits their use. [ABSTRACT FROM AUTHOR]

The use of biomass in the energy industry is the consequence of ongoing efforts to replace Energy from fossil fuels with energy from renewable sources. However, due to the diversity of the biomass, its use as a solid fuel generates waste with diverse and unstable chemical composition. Waste from biomass combustion is a raw material with a very diverse composition, even in the case of using only one type of biomass. The content of individual elements in fly ash from the combustion of biomass ranges from zero to tens of percent. This makes it difficult to determine the optimal recovery methods. The ashes from the combustion of biomass are most commonly used in the production of building materials and agriculture. This article presents the elemental composition of the most commonly used biomass fuels. The results of the analysis of elemental composition of fly ashes from the combustion of forest and agricultural biomass in fluidized bed boilers used in the commercial power industry were presented. These ashes are characterized by a high content of calcium (12.3-19.4%), silicon (1.2-8.3%), potassium (0.05-1.46%), chlorine (1.1-6.1%), and iron (0.8-6.5%). The discussed ashes contained no sodium. Aluminum was found only in one of the five ashes. Manganese, chromium, copper, nickel, lead, zinc, sulfur, bismuth, titanium and zirconium were found in all of the examined ashes. The analysis of elemental composition may allow for a preliminary assessment of the recovery potential of a given ash. [ABSTRACT FROM AUTHOR]

The mineral sequestration using waste products is a method of reducing CO2 emissions that is particularly interesting for major emitters and producers of mineral wastes, such as iron and steel industries. The CO2 emissions from iron and steel production amounted to 6,181.07 kt in 2014 (PNIR 2016). The aforementioned industry participates in the EU emission trading system (EU ETS). However, blast furnace processes produce mineral waste - slag with a high content of CaO which can be used to reduce CO2 emissions. Metallurgical slag can be used to carry out direct (a one-step process) or indirect (two-stage process) process of mineral sequestration of carbon dioxide. The paper presents the degree of carbonation of the examined samples of granulated blast furnace slags defined by the six-digit code (10 02 01) for the waste and the respective two-digit (10 02) chapter heading, according to the Regulation of the Minister of the Environment of 9 December 2014 on the waste catalogue. The carbonation process used the direct gas-solid method. The slags were wetted on the surface and treated with CO2 for 28 days; the obtained results were compared with the analysis of fresh waste products. The analyzed slags are characterized by a high content of calcium (nearly 24%), while their theoretical binding capacity of CO2 is up to 34.1%. The X-ray diffraction (XRD) analysis of the phase composition of slags has revealed the presence of amorphous glass phase, which was confirmed with the thermogravimetric (DTA/TG) analysis. The process of mineral sequestration of CO2 has resulted in a significant amount (9.32%) of calcium carbonate - calcite, while the calculated degree of carbonation of the examined blast furnace slag is up to 39%. The high content of calcium, and a significant content of CaCO3-calcite, has confirmed the suitability of the discussed waste products to reduce carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

When it comes to the production of energy from renewable sources, biomass is the main fuel, burned directly or co-fired with coal, used in the professional power industry. As in the case of coal, the use of biomass in the professional power industry is accompanied by the generation of by-products of the combustion process, primarily in the form of fly ash. These wastes significantly differ from those resulting from coal combustion. Their properties depend primarily on the burned biomass and boiler type. Due to the growing pressure on the use of energy from renewable sources resulting from the E nergy Policy of Poland and the requirements imposed by the E U, more and more by-products are produced. Ashes from the co-firing of biomass are relatively well studied, especially when it comes to those resulting from the combustion in conventional boilers. The by-products of biomass combustion are of limited economic use due to their specific characteristics. The ashes resulting from the combustion in fluidized bed boilers are particularly problematic. The paper presents the research results on the basic properties of the three ashes generated from the combustion of biomass in fluidized bed boilers and one ash resulting from the co-firing of biomass with coal in pulverized coal boiler for the same biofuel type. The conducted analysis of the chemical composition has shown a high content of CaO and CaOw, SO3, and K2O and a low content of SiO2 and Al2O3 compared to ash from co-combustion of biomass. The elemental analysis indicates a high content of: P, S, C l, K, and C a and lower content of chromium and cobalt in the ashes generated from burning of biomass when compared with the ashes produced as a result of co-combustion. All the tested ashes have similar granulometric composition. Particular attention was paid to the leachability of pollutants, which is one of the most important factors determining the use of waste in mining technologies, using mainly the mixtures of fly ash and solid waste from calcium-based flue gas desulphurization (10 01 82). The pH of leachates from the analyzed ashes is the lowest for the ashes resulting from the co-combustion of biomass. The pH value of leachates was approximately 12 for all of the tested samples. The results have shown a high leachability of potassium and chlorides, which is characteristic for by-products resulting from the combustion of biomass, and a high leachability of sulphates due to the type of used boilers. The phase composition is dominated by calcium and potassium carbonates, quartz, K2SO4, halite, sylvite, CaO, MgO. [ABSTRACT FROM AUTHOR]

Abstract: The Kyoto Protocol signed by Poland obliges our country to reduce greenhouse gases emission in the period of 2008 to 2012 by about 6 below the 1990 level. One of the methods of reduction of CO2 emission is its binding via mineral carbonation. The paper presents the methodology of researches and findings on CO2 absorption by cement slurries prepared with the use of most commonly applied cement types. [Copyright &y& Elsevier]

Abstract: The ashes from lignite combustion are characterized by high CaO and free CaO contents and are a potentially interesting material for CO2 bonding, more particularly as theirs economical use is limited. The findings of CO2 absorption by suspensions prepared on the basis of ash from lignite combustion are presented in the paper. On these grounds CO2 sequestration potential via mineral carbonation in ash aqueous suspensions in Poland will be estimated. [Copyright &y& Elsevier]

There is a current focus on replacing the generally accepted conventional power generation technologies with more advanced ones that will better protect the natural environment. The need to limit CO2 emissions from power generation plants presents a problem that must be solved in many countries that use coal or lignite as basic fuels. One potential option is mineral sequestration performed using side products of fossil fuel combustion, such as fluidised bed combustion (FBC) fly ashes. Fluidised bed combustion (FBC) lignite fly ashes are characterised by a high storage capacity of 15.7%. Research conducted with the most commonly used method of direct mineral sequestration—CO2 trapping with fluidised bed combustion (FBC) ash in water suspension—has indicated a very high level of carbonation of CO2, reaching 11%. Calcite was the basic product of carbonation. The calcite content increased from 2% to 12% in the suspension subjected to treatment with CO2. Furthermore, CO2 reduced the pH and limited the leaching of impurities, such as Zn, Cu, Pb, Ni, As, Hg, Cd, Cr, Cl, and SO4. The fly ash suspensions subjected to CO2 treatment can be used in industry in the final stage of carbon capture and utilisation (CCU) technology, which will further contribute to the implementation of the circular economy. [ABSTRACT FROM AUTHOR]