Uses of Lime

Lime is used in environmental, metallurgy, construction, chemical/industrial applications, and many others. The fastest growing use of lime is in environmental applications, where lime is used to comply with air, drinking water, wastewater, and solid waste regulations.

However, the largest single use of lime remains steel manufacturing, where lime is used to remove impurities. Lime is also used to produce other metals. In construction, the dominant use of lime is in soil stabilization for roads, earthen dams, airfields, and building foundations. As an additive in asphalt, lime improves the cohesion of asphalt, reduces stripping, and retards the aging process. Lime is also a key ingredient in mortar and plaster. There are additional chemical and industrial uses of lime, such as manufacturing chemicals and production of precipitated calcium carbonate, described in this area.

AGRICULTURE
Lime, limestone, dolomite and other minerals are used in agriculture and forestry, both to correct soil acidity and to add nutrients that contain magnesium and calcium. These nutrients are essential for healthy plant growth and to increase crop yield. This allows you to better utilize acreage and reduce the impact of intensive agriculture (fertilizers) on the environment, e.g. pollution of ground water.

ALUMINUM INDUSTRY
Lime helps remove silica from bauxite ore during the manufacture of alumina.

BUILDING INDUSTRY
Lime is used in the manufacture of lime silica bricks, insulation and building board materials. Lime is also added to concrete and plaster to improve their performance.

FOOD INDUSTRY
Lime acts as a clarifying agent for sugarcane juice in the manufacture of white sugar. It can also be added during the sugarcane washing process to treat wastewater effluents. In the sugar and alcohol market, milk of lime or lime slurry is used to treat juice and wash sugarcane. Lime is also an ingredient in baking soda and helps fruit and vegetables keep fresh.

INDUSTRIAL WASTE WATER TREATMENT
Lime neutralizes acid wastes generated in industry thereby impeding corrosion and protecting the natural environment. Lime also removes silica, manganese, flourides, iron and other impurities from water.

METAL EXTACTION INDUSTRIES
Lime serves as a "flotation" vehicle in the recovery of copper, mercury, zinc, lead, gold and silver.

PAPER MANUFACTURE
Pulp and paper manufacturer use lime to recover caustic soda during the conversion of wood chips to pulp. Lime bleaches the pulp and also dissolves non-cellulose components of straw and disintegrates it's fibres during the manufacture of strawboard and pasteboard.

POLLUTION CONTROL
Lime and limestones are used to absorb Sulfur Dioxide from exhaust gases in smelters and power generation plants.

ROAD CONSTRUCTION
Lime converts unstable clay subgrades by breaking down clod formations. It creates soil that will not swell or shrink. It can provide a cementing action that stabilizes soil into a steadfast layer impervious water penetration.

SEWAGE TREATMENT
Lime reduces pollution by removing organic matter, phosphates and nitrogen from waste water. It prevents over vegetation in streams and lakes, controls odors from waste ponds and precipitates heavy metals.

SOIL STABILIZATION
Lime can be used to stabalise soil in wet, boggy conditions to allow earthworks to continue.

STEEL INDUSTRY
Lime is used as a flux for purifying steel and for removal of phosphorous, sulphur and silicon impurities. Lime lubricates steel rods as they are drawn through dyes to form wire. As a whitewash coating, lime prevents ingots sticking to the molds during pipe iron casting. A bath of lime neutralizes traces of pickling acid adhering to steel products.

TANNERIES
Lime removes hair and plump hides preparatory to leather tanning.

WATER TREATMENT
Lime treats potable and industrial water supplies, including drinking water for cities and process water used in industry. It softens water by removing bicarbonate hardness and disinfects against bacteria.

SUGAR INDUSTRY
Lime product is slaked in water to produce calcium hydroxide suspension or milk of lime. Milk of lime is added to sugar juice in a process called carbonation which removes the impurities in raw juice before it undergoes crystallization. First, the juice is mixed with lime. This treatment precipitates a number of impurities including multivalent anions such as sulfate, phosphate, citrate and oxalate. These impurities precipitate as salts of large organic molecules such as proteins, saponins, and pectins. In addition, the alkaline condition converts simple sugar, glucose and fructose, and amino acid glutamine to chemically stable carboxylic acids. Left untreated, these sugars and amines would interfere with the crystallization of sucrose.

Next, carbon dioxide is bubbled through the alkaline sugar solution, precipitating the lime as calcium carbonate (chalk). The chalk particles entrap some impurities and absorb the others. Recycling process builds up the size of chalk particles, and natural flocculation occurs when heavy particles settle out in tanks (clarifiers). Final addition of more carbon dioxide precipitates more calcium out of the solution; as it is filtered off, the process leaves a cleaner, golden light-brown sugar solution called thin juice.

Lump Lime, Quick Lime Powder and Hydrated Lime from Upward Agro have been successfully fulfilling the need of sugar industry for over 10 years.