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Sustainability of gypsum products as a construction material

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  • National University of Water and Environmental Engineering
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... The development of environmental and environmental aspects of the building materials industry, green building technologies and health-saving building materials has made it possible to make a technical breakthrough in the application of gypsum binders and materials [1][2][3][4]. This is due to their compliance with all modern requirements for the safety of production, use and disposal [2]. ...
... Energy costs for obtaining semi-aquatic gypsum are significantly lower than in the case of cement or other mineral binders, which meets the solution to the problem of energy conservation. In the case of the use of finished products based on gypsum, there is also no danger to people, animals and plants, which compares them favorably with modern synthetic materials [3]. It should also be noted that the modern development of materials science allows the repeated recycling of gypsum, which until recently, in the 20th century, seemed impossible [3]. ...
... In the case of the use of finished products based on gypsum, there is also no danger to people, animals and plants, which compares them favorably with modern synthetic materials [3]. It should also be noted that the modern development of materials science allows the repeated recycling of gypsum, which until recently, in the 20th century, seemed impossible [3]. At the same time, issues of resource conservation and environmental protection are successfully resolved [4,5,6]. ...
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The possibility of using glass hollow microspheres in self-reinforced gypsum composites in the work is investigated. The need to use microspheres for gypsum products is dictated by modern high requirements for safety and environmental protection to construction sites and the building materials industry. The dispersion characteristics and grain composition of Russian production glass hollow microspheres, as well as the main component, a gypsum binder, were studied. It was established that all compositions contain particles of micro- and nanometer size. It is shown that glass microspheres provide the structure of a composite with a hardened matrix a low density while maintaining the necessary strength without the introduction of expensive and environmentally unsafe chemical additives.
... Most of them can be considered as substitutes for natural gypsum. Synthetic gypsum normally consists of calcium sulphate dihydrate, calcium sulphate hemihydrate and anhydrite [5,6]. ...
... On the other hand, the calcium sulfate source (HH or An) can be obtained from the calcination of mineral gypsum (the most abundant of the sulfate minerals) or from more than 50 sources of synthetic gypsum products (industrial wastes containing a high proportion of calcium sulfate) that are reported as able to be applied as a total or partial substitution for natural gypsum (Lushnikova et al., 2016). Examples of the latter include the anhydrite (An) from fluorgypsum as investigated in this paper; or other examples that include binders based on BFS (Escalante-García et al., 2009), phosphogypsum (Liu et al., 2019(Liu et al., , 2020, citrogypsum (Bensted, 1980), etc. ...
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2) Medicines and Drugs Technology Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil elba1996 (at) iq.ufrj.br 1 -INTRODUCTION Energy availability, supply and use play a central role in the way societies organize themselves, from individual welfare to social and industrial development. By extension, energy accessibility and cost is a determining factor for the economical, political and social interrelations among nations. Considering energy sources, human society has dramatically increased the use of fossil fuels in the past 50 years in a way that the most successful economies are large consumers of oil. However, geopolitical factors related to security of oil supply, high oil prices and serious environmental concerns, prompted by global warming -the use of petrol for transportation accounts for one-third of greenhouse gas emissions (Wyman, 1996) -have led to a push towards decreased consumption. Indeed, the world's strongest economies are deeply committed to the development of technologies aiming at the use of renewable sources of energy. Within this agenda, the substitution of liquid fuel gasoline by renewable ethanol is of foremost importance. Brazil has been a front-runner in the use of renewable fuels. The substitution of gasoline by ethanol started in 1975, when the Brazilian Government launched the "Proálcool Program" (Programa Nacional do Álcool). At the time of the first oil crisis, in the 1970s, the country imported 85% of its oil needs and the potential for ethanol production from sugarcane as a transportation fuel was in good agreement with the Government policy regarding energy supply independence. The Proálcool Program included incentives for distilleries and automobile companies that made ethanol-only cars. Although in the mid-1970s environmental concern was not a major driving force for substituting the use of gasoline, it is worth pointing out the global environmental benefits that have resulted from this policy since then. Presently, the ethanol industry in Brazil runs without government incentives and the biofuel is distributed by the Brazilian oil company Petrobras. The Brazilian fleet of 20 million cars (the total vehicle fleet including cars, light commercials, trucks and buses is around 24 million) runs on either a gasoline blend containing 22-24% ethanol or on 100% ethanol. Natural gas has also been marginally used. Ethanol consumption is forecast to increase as the number of "flex-fuel" cars, with engines able to run on both gasoline blend or ethanol, is forecast to increase from the present 4 million to 15 million in 2013 (Associação Nacional dos Fabricantes de Veículos Automotores -www.anfavea.com.br).
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The hydration of calcium sulphate hemihydrate (CaSO4·0.5H2O) leading to the crystallization of gypsum (calcium sulphate dihydrate – CaSO4·2H2O) has been the subject of several investigations over a long period and a vast amount of data is widely distributed throughout in the literature. In this review article an overall picture of the subject is presented. The properties of the two hemihydrates (α- and β-), their hydration characteristics, the mechanism of their hydration and the crystal growth of gypsum are discussed. Additives modify the microstructures of the hardened gypsum and reduce its strength. A probable mechanism is discussed.
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Paper presents the studies on characterization, beneficiation and utilization of H-acid gypsum, a waste material produced by the neutralization of free sulphuric acid collected during the formation of intermediate dyes. The waste gypsum contains impurity of organic matter like nitro compounds, naphthalene etc. The removal of impurities and improvement in colour was carried out by scrubbing with water, centrifuging and drying. The beneficiated H-acid gypsum was calcined to form β-hemihydrate plaster. The plaster was tested and evaluated for engineering properties such as compressive strength, bulk density, water absorption and porosity. These properties suggest the use of beneficiated H-acid gypsum for making building and ceramic grade plasters and for casting building blocks, board and cementitious binder. Data showed that cementitious binder of low water absorption (9.5%) and adequate compressive strength (19.6 MPa at 28 days) can be produced for use as construction material. The use of waste gypsum will definitely benefit environment and sustainable development.
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Boron ores are used in the production of various boron compounds such as boric acid, borax and boron oxide. Boric acid is produced by reacting colemanite(2CaO·3B2O3·5H2O) with sulphuric acid and a large quantity of borogypsum is formed during this production. This waste causes various environmental problems when discharged directly to the environment. Portland cement is the most important material in the building industry. This material is produced by adding about 3–5% gypsum (CaSO4·2H2O) to clinker as a set retarder. The aim of this study was to stabilize borogypsum, and to produce cements by adding borogypsum instead of natural gypsum to clinker. Concrete using cement produced with borogypsum was tested to find the mechanical properties and the test values were compared with those of concrete from cement with natural gypsum. Compressive strength of concrete from cement produced with borogypsum was found to be higher than that of natural gypsum. Also, the setting time of cement with borogypsum was longer than that of the Portland cement.
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In this study, by using UV-visible adsorption spectrophotometer, Zeta potential analyzer and X-ray photo spectroscopy, the adsorption characteristics and surface electrochemical properties of two types of superplasticizer-β-naphthalene sulfonic acid type (BNS) and polycarboxylate type (PC) and their effects on the fluidity of gypsum plaster were studied. The results show that the adsorption of BNS and PC on gypsum surface approximately conforms to Langmuir's adsorption isotherm. The adsorption of BNS belongs to physical adsorption, its adsorption heat being 14.71 kJ/mol and the thickness of adsorption layer 120 Å; while the adsorption of PC belongs to chemical adsorption, with an adsorption heat of 20.85 kJ/mol and a thickness of adsorption layer of 120 Å. The adsorption conformation of BNS is lying on the flat of gypsum surface, generating weak steric hindrance to inhibit agglomerate of gypsum particles. Its dispersion effect mainly depends on electrostatic repulsive force caused by ζ-potential, which is determined by the adsorbed amount of BNS at the first adsorption layer on gypsum surface. The adsorption conformation of PC is comb-shaped, generating strong steric hindrance by side chains of adsorption layer, thus, its dispersion ability mainly comes from a combination effect of steric hindrance and electrostatic repulsive force. The dispersion by steric hindrance is less affected by the rapid hydration of gypsum, thus, its stability is much better than that of electrostatic repulsive force, resulting in little flow loss of fresh gypsum plaster.
Article
With insufficient source separation, construction and demolition (C&D) waste becomes a mixed material that is difficult to recycle. Treatment of mixed C&D waste generates residue that contains gypsum and organic matter and poses a risk of H(2)S formation in landfills. Therefore, removing gypsum and organic matter from the residue is vital. This study investigated the distribution of gypsum and organic matter in a sorting process. Heavy liquid separation was used to determine the density ranges in which gypsum and organic matter were most concentrated. The fine residue that was separated before shredding accounted for 27.9% of the waste mass and contained the greatest quantity of gypsum; therefore, most of the gypsum (52.4%) was distributed in this fraction. When this fine fraction was subjected to heavy liquid separation, 93% of the gypsum was concentrated in the density range of 1.59-2.28, which contained 24% of the total waste mass. Therefore, removing this density range after segregating fine particles should reduce the amount of gypsum sent to landfills. Organic matter tends to float as density increases; nevertheless, separation at 1.0 density could be more efficient.
Article
Construction and demolition (C&D) debris recycling facilities often produce a screened material intended for use as alternative daily cover (ADC) at active landfills or for shaping and grading at closed landfills. This product contains soil and small pieces of wood, concrete, gypsum drywall, shingles and other components of C&D debris. Concerns have been raised over the contribution of gypsum drywall in C&D debris fines to odor problems at landfills where the product is used. To address such concerns, limitations may be placed on the percentage of gypsum (or sulfate) that can occur, and standardized testing procedures are required to permit valid compliance testing. A test procedure was developed for measuring the gypsum content in C&D debris fines. The concentration of sulfate leached in an aqueous solution was used to estimate the initial gypsum content of the sample. The impact of sample size and leaching time were evaluated. Precision and accuracy increased with increasing gypsum content. Results from replicate samples had an average relative standard deviation of 9%. The gypsum content of fines obtained from different facilities in the US varied widely from 1% to over 25%. These variations not only occurred between differing facilities, but within batches produced within a single facility.
Building Energy Data Book, 1.6.6 Embodied Energy of Interior Wall Assemblies in the
BEDB, 2009. Building Energy Data Book, 1.6.6 Embodied Energy of Interior Wall Assemblies in the U.S., pp. 1-37. Prepared for the Buildings Technologies Program. Energy Efficiency and Renewable Energy U.S. Department of Energy by D&R International, Ltd., 1.6.6 Embodied Energy of Interior Wall Assemblies in the U.S. Available at: http://static1.squarespace.com/ static/513f072ae4b0a96a24469023/t/5410b01ae4b05f0d2fb6861d/1410379802995/docs_ DataBooks_2009_BEDB_Updated.pdf.
A Cradle-to-Gate Life Cycle Assessment of ½″ Regular and 5/8″ Type X Gypsum Wallboard. Prepared for the Gypsum Association by Athena Sustainable Materials Institute, Ottawa, Final Report
  • L Bushi
  • J Meil
Bushi, L., Meil, J., 2011. A Cradle-to-Gate Life Cycle Assessment of ½″ Regular and 5/8″ Type X Gypsum Wallboard. Prepared for the Gypsum Association by Athena Sustainable Materials Institute, Ottawa, Final Report, November 2011 [December 21, 2011], 132 pp.
Building Mineral Binding Materials. Infra-Ingeneria
  • L Dvorkin
  • O Dvorkin
Dvorkin, L., Dvorkin, O., 2011. Building Mineral Binding Materials. Infra-Ingeneria, Moscow. pp. 27-90 (in Russian).
Properties of Gypsum Binders Modified With Complex Admixtures. Ibausil-Internationale Baustofftagung
  • L Y Dvorkin
  • N V Lushnikova
Dvorkin, L.Y., Lushnikova, N.V., 2009. Properties of Gypsum Binders Modified With Complex Admixtures. Ibausil-Internationale Baustofftagung, Tagunsbericht, Weimar, Institut für Baustoffkunde, Band 2, pp. 1-0701-1-0707.
Design Strategy of Foam Gypsum Proportioning
  • L Y Dvorkin
  • О L Dvorkin
  • A V Bezusyak
  • N V Lushnikova
  • I V Kovalyk
Dvorkin, L.Y., Dvorkin, О.L., Bezusyak, A.V., Lushnikova, N.V., Kovalyk, I.V., 2012. Design Strategy of Foam Gypsum Proportioning. Ibausil-Internationale Baustofftagung, Tagunsbericht, Weimar, Institut für Baustoffkunde, Band 1, pp. 1-0986-1-0992.
European Life Cycle Assessment on Plasterboard European Environmental Declaration-Explanatory Note. Scientific and Technical Committee Environment and Raw Materials Committee
ELCAP, 2010. European Life Cycle Assessment on Plasterboard European Environmental Declaration-Explanatory Note. Scientific and Technical Committee Environment and Raw Materials Committee. 5 pp. Available at: http://www.eurogypsum.org/_uploads/ dbsattachedfiles/lcaplasterboardexplanatorynote.pdf.
Environmental Product Declaration. Typical (5/8″ Type X) North American Gypsum Boards
  • Epd Nagb
EPD NAGB, 2014. Environmental Product Declaration. Typical (5/8″ Type X) North American Gypsum Boards. Declaration number: FPI/GA/01/2014 Issued May 2014 Valid until May 2019. Available at: http://www.gypsum.org/wp/wp-content/uploads/2013/12/Gypsum-2014-FINAL-May-13-.pdf.
Gypsum Materials and Products: Production and Application
  • A V Ferronskaya
Ferronskaya, A.V. (Ed.), 2004. Gypsum Materials and Products: Production and Application. ACB Publishing, Moscow. 488 pp. (in Russian).
Gypsum-Based Products: Environmental Product Declaration
  • Gbp Epd
GBP EPD, 2009. Gypsum-Based Products: Environmental Product Declaration, first ed. Bundesverband der Gipsindustrie e.V. Forschungsvereinigung der Gipsindustrie e.V. 16 pp. Available at: http://www.hunton.no/wp-content/uploads/2013/06/EPD-Gypsum-Fibreboards-EN15283-2-Produktdeklaration_E_09-06-09.pdf.
Managing Editor) 2009. Gypsum Construction Handbook, sixth ed. Construction Industry by CGC Inc., RS Means Company
  • M Greene
Greene M. (Managing Editor) 2009. Gypsum Construction Handbook, sixth ed. Construction Industry by CGC Inc., RS Means Company, Kingston, MA, 556 pp.
Rheological behaviour of gypsum plaster pastes with polyamide powder wastes. 25th Anniversary Session for ACI 228-Building on the Past for the Future of NDT of Concrete
  • S Gutiérrez-González
  • M M Alonso
  • J Gadea
  • A Rodríguez
  • V Calderón
Gutiérrez-González, S., Alonso, M.M., Gadea, J., Rodríguez, A., Calderón, V., 2013. Rheological behaviour of gypsum plaster pastes with polyamide powder wastes. 25th Anniversary Session for ACI 228-Building on the Past for the Future of NDT of Concrete. Constr. Build. Mater. 38, 407-412.
Global Industry Markets and Outlook
  • Anhydrite Gypsum
Gypsum and Anhydrite, 2014. Global Industry Markets and Outlook, 11th ed. Available at: http://www.roskill.com/reports/industrial-minerals/gypsum.
Embodied Energy and Carbon Footprint Database
  • G P Hammond
  • C I Jones
Hammond, G.P., Jones, C.I., 2006. Embodied Energy and Carbon Footprint Database. Department of Mechanical Engineering, University of Bath, United Kingdom. Available at: http://www. circularecology.com/embodied-energy-and-carbon-footprint-database.html.
Sustainable architecture module
  • J.-J Kim
  • B Rigdon
Kim, J.-J., Rigdon, B., 1998. Sustainable architecture module. In: Graves, J. (Ed.), Qualities, Use, and Examples of Materials for Architects and Builders, 2. Plaster and Board Materials, fifth ed. National Pollution Prevention Center for Higher Education, Ann Arbor, pp. 384-393.
Life-Cycle Assessment Summary. The Gypsum Association
LCAS, 2013. Life-Cycle Assessment Summary. The Gypsum Association. January, 10 pp. Available at: http://www.gypsum.org/wp/wp-content/uploads/2014/02/Life-CycleAssessmentSummary02-13.pdf.