Structurally controlled synthesis of calcium sulphate dihydrate from industrial wastes of spent sulphuric acid and limestone

Kamarou, Maksim; Kuz'menkov, M. I.; Korob, Natalia; Kwapiński, Witold; Romanovski, Valentin

doi:10.1016/j.eti.2019.100582

Cited by 30 publications

(25 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Figure 3(a) shows that the shape of the crystals of synthetic anhydrite is close to the required prismatic shape, 16 however, they have more rounded corners. This can be explained by the nature of the origin of the material itselfartificially obtained using chemical synthesis.…”

Section: Resultsmentioning

confidence: 88%

“…Based on previous studies on the preparation of synthetic calcium sulfate dihydrate, 16 it was concluded that, when using a limestone suspension as a neutralizing agent, the resulting synthetic gypsum (due to its structure and size) and the shape of the particles make it possible to obtain maximum strength characteristics. The particle shape of synthetic anhydrite and particle size distribution are shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Detailed composition of used wastes is presented in paper. 16 The particle size distribution of used screening fines of limestone are shown in Fig. S1.…”

Section: Methodsmentioning

confidence: 99%

“…Previous work 16 on the production of synthetic gypsum and gypsum binders from synthetic calcium dihydrate showed that the characteristics of the precipitated crystals of calcium sulfate dihydrate and the strength characteristics of the binder based on it are influenced by the order in which the initial reagents are introduced into the reactor. As a result, it was found 16 that, at the same synthesis temperature, the use of the method of merging the components, involving the addition of sulfuric acid to the calcium carbonate suspension (direct order), is most preferable because, in most cases, it leads to an increase in the average size of the precipitated crystals of calcium sulfate dihydrate and increases the strength characteristics of a binder based on it. In addition, the implementation of the direct order of deposition simplifies the instrumentation of the technological process.…”

Section: Introductionmentioning

confidence: 99%

“…In addition, the implementation of the direct order of deposition simplifies the instrumentation of the technological process. 16 From the diagram of the CaCO 3 -H 2 SO 4 -H 2 O system, it follows that direct crystallization from sulfuric acid solutions of calcium sulfate anhydrite is possible only at a concentration of H 2 SO 4 above 52-54 wt.%. 17,18 For crystallization of anhydrite from solutions of H 2 SO 4 of lower concentration, a significant increase in temperature is required, and vice versa.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes

Kamarou

Korob

Hil

et al. 2021

J of Chemical Tech & Biotech

Self Cite

View full text Add to dashboard Cite

BACKGROUND: A high-quality anhydrite binder could be produced due to the exergy of sulfuric acid in the CaCO 3 -H 2 SO 4 -H 2 O system derived from industrial wastes. Waste of sulfuric acid derived from the production of heat-resistant fibers and wastes of limestone that was formed on the metallurgical enterprise were used for the synthesis of anhydrite. Such a product is safe from an environmental point of view and has many advantages, both operational and economic, over standard gypsum binders.RESULTS: The optimal technological parameters have been established and a technological scheme for producing anhydrite excluding the stage of calcium sulfate dihydrate formation has been proposed. Anhydrite production in the CaCO 3 -H 2 SO 4 -H 2 O system, due to the exergy of sulfuric acid, is a promising technology to replace the traditional thermal technology for producing anhydrite. This technology can reduce fuel costs because the required synthesis temperature is 95-105°С, instead of 800-1000°С in the traditional one, and this significantly reduces the cost of manufactured products. CONCLUSION:The maximum yield of synthetic anhydrite was provided by a limestone suspension taken in a stoichiometric amount. This neutralizing agent makes it possible to obtain particles of a prismatic shape, the size of which is generally more than 20 ∼m.

show abstract

Section: Resultsmentioning

confidence: 88%

Section: Resultsmentioning

confidence: 99%

“…Detailed composition of used wastes is presented in paper. 16 The particle size distribution of used screening fines of limestone are shown in Fig. S1.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes

Kamarou

Korob

Hil

et al. 2021

J of Chemical Tech & Biotech

Self Cite

View full text Add to dashboard Cite

show abstract

Gypsum Binder With Increased Water Resistance Derived From Membrane Water Desalination Waste

Romanovski,

Moskovskikh,

Tan

et al. 2024

Engineering Reports

View full text Add to dashboard Cite

A method has been developed for separating a mixture of calcium, magnesium and sodium sulfates obtained through the interaction of sulfuric acid and waste from the water purification process generated by using membrane filters. The primary goal of this method is to extract gypsum and produce gypsum‐based binders. Patterns were identified regarding how various types, ratio and quantities of additives: blast furnace slag, granite screenings, portland cement, electric steel smelting slag affect the water‐gypsum ratio, strength properties, and water resistance of high‐strength gypsum binders. It was found that adding a single‐component additive specifically to enhance water resistance does not significantly impact these properties. Complex additives have been developed based on Portland cement, granulated blast furnace slag, electric furnace slag, expanded clay dust, and granite screenings of various fractions. These additives are designed to maximize the water resistance of high‐strength gypsum binder based on synthetic calcium sulfate dihydrate. As a result, the water resistance coefficient increased from 0.45 to 0.52. Additionally, a technological block diagram of the process has been proposed.

show abstract

High Strength Anhydrite Cement Based on Lime Mud From Water Treatment Process: One Step Synthesis in Water Environment, Characterization and Technological Parameters

Kamarou,

Tan,

Moskovskikh

et al. 2024

Engineering Reports

View full text Add to dashboard Cite

In the process of water treatment from surface water sources, lime mud as waste is formed. This waste contains CaO, Ca(OH)2, and CaCO3. The article proposes a comprehensive method for processing lime mud into high‐strength anhydrite cement. The method involves the interaction of lime mud with waste sulfuric acid from the production of polymer fibers using a structure‐controlled method in the (CaO·Ca(OH)2·CaCO3)—H2SO4—H2O system at a temperature of 40°C. X‐ray diffraction analysis showed the presence of CaSO4 and CaSO4·0.62H2O phases with a purity of 99.8%. The structure‐controlled method makes it possible to control the formation and growth of calcium sulfate crystals of the required shape and size, due to which it is possible to obtain anhydrite cement with desired properties. Combined grinding of synthetic anhydrite with activator additives makes it possible to obtain anhydrite cement with a strength of up to 28.5 MPa.

show abstract

Structurally controlled synthesis of calcium sulphate dihydrate from industrial wastes of spent sulphuric acid and limestone

Cited by 30 publications

References 11 publications

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes

Gypsum Binder With Increased Water Resistance Derived From Membrane Water Desalination Waste

High Strength Anhydrite Cement Based on Lime Mud From Water Treatment Process: One Step Synthesis in Water Environment, Characterization and Technological Parameters

Contact Info

Product

Resources

About

Structurally controlled synthesis of calcium sulphate dihydrate from industrial wastes of spent sulphuric acid and limestone

Cited by 30 publications

References 11 publications

Low‐energy technology for producing anhydrite in the CaCO3–H2SO4–H2O system derived from industrial wastes

Low‐energy technology for producing anhydrite in the CaCO3–H2SO4–H2O system derived from industrial wastes

Gypsum Binder With Increased Water Resistance Derived From Membrane Water Desalination Waste

High Strength Anhydrite Cement Based on Lime Mud From Water Treatment Process: One Step Synthesis in Water Environment, Characterization and Technological Parameters

Contact Info

Product

Resources

About

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes

Low‐energy technology for producing anhydrite in the CaCO₃–H₂SO₄–H₂O system derived from industrial wastes