Caso

Caso (Asturian: Casu) is a municipality in the Spanish Principality of Asturias. It shares a boundary to the North with Piloña; to the East with Ponga; to the South with León and to the West with Sobrescobio and Laviana.

Most of the inhabitants of Caso live in the Nalón Valley, on which the largest town is the capital El Campu. The town is divided in two neighbourhoods: L'Arrobiu and El Barru.

The municipalities of Caso and Sobrescobio together constitute the Redes Natural Park, designated by the UNESCO as a Biosphere Reserve. The Natural Monument of the Cueva Deboyu (the Nalón River passes through a cave in the mountain) is also located in Caso. Caso is famous for its landscape, European beech forests, wood handcraft and its Casín cheese.

In the past, most of Caso's people worked in coal mining and livestock farming. Nowadays, tourism has become one of the more important activities in Caso, but farming is still the most relevant.

The Dam of Tanes provides electric energy and drinking water to the central part of Asturias.

Calcium sulfite

Calcium sulfite, or calcium sulphite, is a chemical compound which is the calcium salt of sulfurous acid with the molecular formula CaSO₃. Some common uses areits production in flue gas desulfurization (FGD), as a food additive, and in the production of calcium sulfate. It commonly reacts to create calcium sulfite hemihydrate when in the presence of moist air.

Uses

Wood Pulp Production

Calcium sulfite can be used in the production of wood pulp through the Kraft Process. Chemical wood pulping is the removal of cellulose from wood by dissolving the lignin that binds the cellulose together. Calcium sulfite was used, but has been largely replaced by magnesium and sodium sulfites and bisulfites to attack the lignin[].

Food Additive

As a food additive it is used as a preservative under the E number E226. It is commonly used in preserving wine, cider, fruit juice, canned fruit and vegetables. Sulfites are strong reducers, as sulfate formation is favored so they act as somewhat of an O₂ scavenger to preserve food.

Calcium sulfate

Calcium sulfate (or calcium sulphate) is the inorganic compound with the formula CaSO₄ and related hydrates. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. One particular hydrate is better known as plaster of Paris, and another occurs naturally as the mineral gypsum. It has many uses in industry. All forms are white solids that are poorly soluble in water.

Structures

The compound exists in three levels of hydration:

Uses

The main use of calcium sulfate is to produce Plaster of Paris and stucco. These applications exploit the fact that calcium sulfate forms a moldable paste upon hydration and hardens as a hemihydrate. It is also convenient that calcium sulfate is very poorly soluble in water, so structures do not dissolve.