Gypsum Aging Experiment
Preparation of α-High Strength Gypsum from Flue Gas …
2 Experimental 2.1Materials FGD gypsum was produced for FGD system at a plant in Tianjin, China. Sodium chloride (NaCl), ... 3.1 synthesized crystals are completely transformed to Pretreatment of FGD gypsum The hydrothermal-aging method was employed to pretreat the washed FGD gypsum. As shown in Fig.2(a), the washed FGD gypsum was ...
The aging of gypsum in underground mines
The aging properties of gypsum extracted from two underground mines in France (Livry–Gargan and Grozon) have been highlighted by means of observation performed using scanning electron microscopy ...
Determination of Young's Modulus of Gypsum Blocks …
where l is the length of the gypsum block, m is the mass of the gypsum block, f is the fundamental longitudinal resonant frequency of the gypsum block, b is the width of the gypsum block and t is the thickness of the gypsum block. Fig. 3 The measurement line – control notebook, vibration control station Bruel&Kjaer Front-end 3560-B-
Influence of the Calcination Temperature of Synthetic Gypsum …
During the experiment, the particle diameter distribution of aqueous suspensions of building and synthetic gypsum particles (before and after calcination) was determined using the Fraunhofer laser ...
Impact of accelerated climatic aging on the behavior of gypsum …
Based on previous work on a lime-straw composite [12], four mixtures using two water/binder (W/B = 1.1 and 1.6) and three straw/binder (S/B = 0.2, 0.3, 0.4) ratios were tested to find the optimal composite with the lowest thermal conductivity and mechanical strength under its own weight in accordance with the European standard. Three sample preparation methods for …
Effects of various gypsum on early-age hydration …
and contents of gypsum were incorporated into MOCP, and their early-ages exotherm characteristics were tested and analyzed. Meanwhile, the hydration kinetic parameters of gypsum-modied MOCP were calculated, and the inuence mechanism of gypsum on the hydration process of MOCP was discussed. Experimental details Materials LBM, gypsum, MgCl 2
Mechanism of mercury vapor release from flue gas desulfurization gypsum
DOI: 10.1016/J.FUPROC.2016.10.015 Corpus ID: 99005274; Mechanism of mercury vapor release from flue gas desulfurization gypsum @article{Zhu2017MechanismOM, title={Mechanism of mercury vapor release from flue gas desulfurization gypsum}, author={Zhen-wu Zhu and Yuqun Zhuo and Yaming Fan and Zhi-Peng Wang}, journal={Fuel Processing Technology}, …
Insights into active and passive carbon sequestration and …
Batch experiments were conducted to collect data for obtaining insights into the chemical mechanisms and kinetics of red mud neutralization by both atmospheric (passive treatment) and injected CO2 (active treatment) in the absence and presence of gypsum. Active treatments allowed effective sequestration of CO2 within 1 h. A mixing ratio of gypsum to red …
Experiments on ageing effect of gypsum rock induced by …
To investigate the water-induced ageing effect on gypsum rock, different water environment conditions were simulated in the laboratory, including different air humidity conditions and saturated ...
The dissolution kinetics of natural gypsum: a case study of …
The dissolution kinetics of different varieties of natural gypsum samples with different porosity and content of insoluble impurities are experimentally investigated under unsaturated conditions. The main goal of this work is to verify whether and how the petrophysical and petrographic nature of gypsum influence its dissolution rate. Gypsum samples were taken …
Insights into stable strontium isotope fractionation in marine gypsum …
The age of the gypsum sample is 1600–1650 years B.P. (Rouwendaal, 2017), ... Ca/Sr ratios of both marine aragonite and the fluid inclusions are distinctly lower than those of the gypsum, and the experimental gypsum samples broadly fit the trajectory of such mixing. However, to explain the composition of the samples, one would have to assume ...
Influence of the Calcination Temperature of …
The paper assesses the influence of the calcination temperature of synthetic gypsum binder 14 on the binding properties of innovative gypsum pastes, as well as on masonry and plastering mortars.
Influence of the Calcination Temperature of …
During the experiment, the particle diameter distribution of aqueous suspensions of building and synthetic gypsum particles (before and after calcination) was determined using the Fraunhofer laser method.
Physical and mechanical properties of gypsum-based …
In this study, building gypsum was the β-hemihydrate gypsum (β − CaSO 4 ⋅ 0.5 H 2 O) form Jiangsu Nanjing Efful Science and Technology Co., Ltd., China. The 2 h compressive strength and 2 h flexural strength are 7.0 and 3.2 MPa, respectively [5]. The cement used in the experiment was ordinary Portland cement P·O 42.5 from Conch Cement Co ...
Gypsum | Properties, Formation, Uses and Deposits
Gypsum is a valuable mineral resource used in construction, agriculture, industry, and various other applications. Its wide distribution ensures a steady supply for these diverse uses around the world. Application and Uses Areas of Gypsum. Gypsum is a versatile mineral with a wide range of applications in various industries.
Effects of various gypsum on early-age hydration behavior …
The early-age compressive strength of the gypsum-modified MOCP is reduced due to the reduction in the reaction product (5-phase), but NG can act as a micro-aggregate to alleviate its negative impact on the sample strength. ... Experimental method. Table 3 shows the mix proportions of gypsum-modified MOCP. The molar ratio of MgO/ MgCl 2 ·6H 2 O ...
From atom level to macroscopic scale: Structural mechanism …
First study of gypsum single crystal dehydration using X-ray absorption tomography. Evidence and mechanism of a multi-scale crack pattern due to structure change. How stress …
Tuning the growth morphology of gypsum crystals by …
Characterization of gypsum microstructures formed in the presence of 1000 ppm PVP-co-PAA in slow precipitation experiments at a dosing rate of 0.25 mL/min: (a) PXRD pattern of the product (blue) compared to reference data for pure gypsum from the literature (black) [39], (b) IR spectrum, and (c) thermogram showing the mass loss upon heating ...
Preparation of α-High Strength Gypsum from Flue Gas …
The synthesis of α -calcium sulfate hemihydrate ( α -CSH) from flue gas desulfurization (FGD) gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtain α -CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was …
Experimental Study on Physical and Mechanical Properties of Gypsum …
In order to study the physical and mechanical properties of gypsum rock samples in three states (natural, high-temperature dehydration and hydration time), natural gypsum rock was put into high-temperature condition of 220°C for dehydration treatment, and then the high-temperature dehydrated gypsum rock was treated with different hydration time, and the …
Adhesion of Gypsum Plaster Coatings: Experimental Evaluation
Nearly 95% of the Brazilian production of natural gypsum comes from the state of Pernambuco, from the Araripe Gypsum Center. Of the 95%, that is to say, of the 1.3 million ton/year production, 61% is allotted to the making of blocks and plates, 35% for coverings, 3% for ceramic moulding, and 1% for other uses.
Response of Groundnut Treated Seed to Accelerated Ageing …
An investigation was carried out to study the effects of accelerated aging on treated seed with gypsum and lime (lime sludge) to seed crop of groundnut variety TAG-24 on seedling parameters ...
(PDF) Improvement of Local Gypsum Plaster …
Abstract:- An investigational study had been done in this research to improve the setting time of Local Gypsum Plaster by using two additives, namely : Tree Glue Powder (TGP) and Polyvinyl...
DEVELOPMENT OF A MULTICOMPONENT GYPSUM CEMENT …
An active 3-factor experiment was planned. The fol-lowing were studied: the compressive strength of hardened gypsum-cement binder samples in 2 hours of hardening – R comp2 (Y 1 ); at 28 days of age – R comp28 (Y 2 ); as well as the mobility of the gypsum–cement mixture – P (Y 3 ) and the timing of the beginning of setting - T (Y 4 ).
Mercury release and fraction transformation during …
The results indicated that mercury could be released from desulfurization gypsum during aging process and the release process could be promoted via ultraviolet irradiation.
Impact of accelerated climatic aging on the behavior of …
Freezing-thawing and wetting-drying accelerated aging tests are considered to simulate outdoor conditions. Two straw-gypsum plaster composites were designed. Long-term …
Impact of aging on the hydration of tricalcium aluminate (C3A)/gypsum
Figure 13: Powder XRDanalysis of the 3 days aged C3Ac/gypsummix before initial ettringite formation (top) and before (middle) and after (bottom) final ettringite crystallization, shown in the 2θ range of 5–30°. - "Impact of aging on the hydration of tricalcium aluminate (C3A)/gypsum blends and the effectiveness of retarding admixtures"
Naica's crystal cave captivates chemists
The researchers found that gypsum crystals form via an unexpected type of nucleation: they grow from nanoclusters of CaSO 4 that coalesce rather than form a tiny starting crystal of gypsum, as ...
Insights into active and passive carbon sequestration and …
Batch experiments were conducted to collect data for obtaining insights into the chemical mechanisms and kinetics of red mud neutralization by both atmospheric (passive treatment) and injected CO2 ...
Impact of accelerated climatic aging on the behavior of gypsum plaster-straw material for building thermal insulation
In this work, the improvement of the setting time (S.T.) of the Plaster of Paris produced from gypsum deposits of Jabal Mulaih, in Tafila, south Jordan, was investigated. The setting time of …
The aging of gypsum in underground mines
The aging properties of gypsum extracted from two underground mines in France (Livry–Gargan and Grozon) have been highlighted by means of observation performed using scanning electron microscopy on samples taken along horizontal boreholes drilled through to the middle of several pillars. ... Experimental Investigation on the Mechanical ...
Mercury release and fraction transformation during desulfurization
The results indicated that mercury could be released from desulfurization gypsum during aging process and the release process could be promoted via ultraviolet irradiation. The release amount increased with the irradiation time and intensity (up to 25.1% of the total initial amount). ... This work was kindly co-funded by the National Natural ...
Impact of aging on the hydration of tricalcium aluminate (C3A)/gypsum
Figure 3: Mass increase of binary C3A/gypsum mixtures resulting from aging at 90% relative humidity (RH) and 35 °C. - "Impact of aging on the hydration of tricalcium aluminate (C3A)/gypsum blends and the effectiveness of retarding admixtures" ... this experiment was conducted to prepare gypsum-based sandless self-leveling (PGSL) … Expand. PDF.