Calcium sulfate is an important construction material. More than 1600 million square meters of interior surfaces are covered with plasterboards in Europe each year. Plasterboard manufactured by transforming mined or recycled gypsum (CaSO4 × 2 H2O) to bassanite ½H2O) a time- and energy-consuming heating process. A fast sustainable way produce solvent-assisted milling, thereby eliminating the nee...

Water being an essential component for plant growth and development, its scarcity poses serious threat to crops around the world. Climate changes and global warming are increasing the temperature of earth hence becoming an ultimate cause of water scarcity. It is need of the day to use potential soil amendments that could increase the plants' resistance under such situations. Biochar and gypsum ...

We have developed a new method for measuring the isotopic composition (δ18O and δD) of different types of bonded water (e.g., molecular water, hydroxyl) contained in hydrated minerals by coupling a thermal gravimeter (TG) and a cavity ringdown laser spectrometer (CRDS). The method involves precisely step-heating a mineral sample, allowing the separation of the different types of waters that are...

Revised version 29 November 2006 Abstract— We have performed holographic interferometry measurements of the dissolution of the (010) plane of a cleaved gypsum single crystal in pure water. These experiments have provided the value of the dissolution rate constant k of gypsum in water and the value of the interdiffusion coefficient D of its aqueous species in water. D is 1.0×10−9 m s, a value cl...

The dehydration of gypsum CaSO4.2H20 has been studied, at negligible water vapour pressure, by in situ infrared (IR) spectroscopy and by thermogravimetry to determine whether intermediate phases (CaSO4.nH20) exist, other than the hemihydrate with n=0.5, and also to compare the mechanism of the dehydration process when measured by two techniques with very different correlation lengths. Thermogra...

Applications of animal manures have increased soil test P values in many parts of the USA and thus increased the risk that soil P will be transferred to surface water and decrease water quality. To continue farming these areas, landowners need tools to reduce the risk of P losses. A field experiment was conducted near Kurten, TX, on a Zulch fine sandy loam (thermic Udertic Paleustalfs) with Bra...

Gypsum (calcium sulfate dihydrate) is one of the most used inorganic binding materials in world. During calcination, calcium subhydrates are formed and, for technical reasons, mixed with water to form dihydrate again. Therefore, dehydration process gypsum and rehydration hemihydrate were investigated. This technically performed three different ways. Heating up, i.e., a rotary kiln, leads prefer...

High levels of accumulated phosphorus (P) in soils of the Delmarva Peninsula are a major source of dissolved P entering drainage ditches that empty into the Chesapeake Bay. The objective of this study was to design, construct, and monitor a within-ditch filter to remove dissolved P, thereby protecting receiving waters against P losses from upstream areas. In April 2007, 110 Mg of flue gas desul...

Gypsum is a mineral dust consisting of calcium sulfate and is commonly used in building construction. We here report the first case of an acute calcium sulfate aspiration. An accidental avalanche of fine gypsum powder covered entirely a silo worker. He aspirated a large amount of gypsum powder without loosing consciousness. At admission to the emergency department the patient was breathing spon...

The basis for some common gypsum wallboard mold remediation practices was examined. The bottom inch of several gypsum wallboard panels was immersed in bottled drinking water; some panels were coated and others were untreated. The panels were examined and tested for a period of 8 weeks. This study investigated: (a) whether mold growth, detectable visually or with tape lift samples, occurs within...