It is important to understand the effect of each type of lime before use:
A. Limestone powder (CaCO3): made by crushing fine limestone. This effect is slow, usually from 2-6 months after application depending on the fine powder of stone;
B. Calcined lime (CaO): is produced by calcining lime in a kiln such as bricks at a temperature of about 900-1,000oC. This type is strongest and fastest but easily burns when exposed to water;
C. Slaked lime (Ca (OH) 2): produced by irrigating lime with a quantity of water approximately equal to its weight, then lime it into powder, heat (about 150oC) and evaporate. This lime effect is also quite fast
D. Lime gypsum (CaSO4): This is a special form of lime that contains sulfur, but should not be used in acid soil.
1. Chemical Uses of Lime
Lime is a basic industrial chemical that is used as a component in many other chemical processes:
+ Calcium Carbide and Cyanimide
+ Citric Acid
+ Calcium Hypochlorite
+ Miscellaneous Chemical Uses
Lime is employed in the manufacture of many other inorganic and organic chemicals and pharmaceuticals. Most of the calcium organic and inorganic salts are produced by reacting the various acids with lime (the base). Among the most important inorganic products that use lime are calcium phosphates (mono, di, and tri), fluoride, bromide, ferrocyanide, and nitrate. Lime is used in the manufacture of organics such as calcium acetate, stearate, oleate, tartrate, lactate, citrate, benzoate, and gluconate.
Lime is also used as a neutralizing agent in the manufacture of chrome chemicals (bichromate); for purification of salt brines; to aid in the concentration of glucose and dextrin; to make metallic calcium; as soda-lime, an absorbent and gas purifier; and for countless other minor or isolated purposes, such as for CO2 absorption, as a desiccant, etc.
Lime is used in the production of ethylene or propylene glycol via the chlorohydrin process. Ethylene gas, obtained readily from petroleum refineries, is chlorinated to form ethylene dichloride, which in turn is reacted with lime to produce ethylene glycol.
2. Industrial Uses of Lime
a) Sugar Refining
Lime is essential to the production of sugar from both sugar cane and sugar beets. It is also used to purify sugar from other sources, such as maple or sorghum, although these are produced in much smaller quantities.
Sugar cane and sugar beets are harvested and processed with water to form raw juice, which has low pH and contains dissolved impurities. Lime is added to the juice to raise the pH and to react with the impurities to form insoluble calcium organic compounds that can be removed. Excess lime is removed by carbonation or by the addition of phosphoric acid. This process may be repeated several times depending on the purity of final product required.
b) Food Industry
In food technology, lime is both a neutral substance to absorb moisture and carbon dioxide escape, as well as a good preservative food.
Lime products are used to clean water for soft drinks, provide a binding agent for the masa in tortillas, and even serve as a calcium supplement in your orange juice or baby food.
c) Pulp and Paper Industry
In the paper industry, lime is often used to reconstitute caustic soda from surplus sodium carbonate from the pulp making process. Quickly lime to make additives to increase whiteness, improve the surface as well as reduce the transparency.
In paper mills, lime is used as a water softener.
3. Metallurgical Uses of Lime
a) Non-ferrous metals
Lime is commonly used in the selection of sulfide ores for easy retrieval of metals upon request. This application is implemented in the lead, gold, nickel, zinc and copper mining industries.
+ Lime used in metal extraction process:
- We are often used in the selection of sulfide ores for easy collection of metals as required. This application is implemented in the lead, gold, nickel, zinc and copper mining industries.
- I used to increase and control pH in cyanide solutions. Thanks to the ability to adjust pH, lime plays a role in maintaining liquid cyanide solution, thus avoiding the formation of cyanide and escape into the environment.
+ Lime used in treating acid-containing waste generated in the process of metallurgical and mineral mining
In the lime mining industry it is vital to adjust the pH of the wastewater from the mining process and to dry the mine. Lime regulates pH and wastewater purification from metal and soluble salts in accordance with environmental protection regulations.
b) Iron & Steel
The steelmaking industry uses lime and limestone products to facilitate the steelmaking process and to remove impurities in the steel.
This involves the use of very high quality lime as a cleaner or fusion agent. In the form of lumps, lime rapidly produces alkaline scales with silicon dioxide in the steel, ensuring rapid removal of sulfur, phosphorous and other impurities in the steel.
Use a mixture of lime powder and fluorite to produce low sulfur steel
Municipalities, industrial facilities, utilities, and mining operations rely on lime to help comply with environmental regulations. Lime is used to treat stack gases from power plants, industrial facilities, and medical and hazardous waste incinerators. Lime absorbs and neutralizes sulfur oxides from these gases, helping to prevent acid rain and reducing emissions of hazardous air pollutants, including mercury.
Lime is vital to municipalities, which use lime for potable water softening and to remove impurities from drinking water. Furthermore, lime is a highly cost-effective method to treat sewage sludge and animal waste from concentrated animal feeding operations. Likewise, industrial facilities and mining operations use lime to treat wastewater by adjusting the pH of acidic wastewater, removing phosphorus and nitrogen, and promoting clarification.
a) Animal Waste
b) Biosolids and Sludge
c) Hazardous Wastes
d) Flue Gas Desulfurization
e) Waste water
5. Agriculture - Aquaculture
Lime is not just a fertilizer that provides calcium (Ca) for plants but also many other uses that chemical fertilizers do not have: lime blocking soil degradation; Lard deterioration of salt; Lime inhibits the growth of pathogenic fungi in the soil; and lime promote the effect of organic fertilizers, inorganic fertilizers and herbicides.
It is important to understand the effect of each type of lime before use:
+ Limestone powder (CaCO3): made by crushing fine limestone. This effect is slow, usually from 2-6 months after application depending on the fine powder of stone;
+ Calcined lime (CaO): is produced by calcining lime in a kiln such as bricks at a temperature of about 900-1,000oC. This type is strongest and fastest but easily burns when exposed to water;
+ Slaked lime (Ca (OH) 2): produced by irrigating lime with a quantity of water approximately equal to its weight, then lime it into powder, heat (about 150oC) and evaporate. This lime effect is also quite fast
+ Lime gypsum (CaSO4): This is a special form of lime that contains sulfur, but should not be used in acid soil.
- Lime provides Calcium for plants. Calcium is a secondary nutrient, so plants need more calcium to strengthen the cell wall. Therefore, Calcium deficiency is easy to fall, susceptible to pests, fruit or crack; When the young leaves are disturbed severe deformation, curly and dead dry. In addition, calcium also helps plants detoxify, increase resistance to adverse conditions of hot sun, salty and alum.
- Lime blocks soil degradation. In soils with alum, intensive soil, upland soil (urea) and potassium fertilizers, soil degradation is relatively rapid. When the soil is degraded, the yield of the crop decreases with the time of cultivation, the clay minerals in the soil are destroyed, the soil loses its structure, becomes discrete, softens when exposed to water, and binds when dry, The land becomes cluttered tight. If the degradation persists, the soil becomes old, discolored, poorly planted, yields, and quality deteriorate, and soil fertility can not be restored. Liming (limestone powder) in the rainy season is one of the effective measures to stop this degradation process, reducing iron (Fe), aluminum (Al) and manganese (Mn) damage to crops. soil structure is good ventilation, good water absorption.
- Lime reduces the damage of salty. Rising sea levels due to the impact of climate change to seawater intrusion deep into land causes salinity to many coastal areas. Saline soil is lost structure, discrete; Plants do not absorb water and nutrients. In order to limit the harmful effects of saline, saline soils with alum should be baked lime (CaO) for saline washing, and saline soils should not be applied with lime (CaSO4)
- Lime inhibits the growth of pathogenic fungi in the soil. Soils that become sour when degraded are favorable conditions for pathogenic fungi in the soil. On the land, the fungus causes melon to be run on the rope, the wilted leaves, ... Golden leaf disease, root rot, flowering buds, One of the measures to inhibit the growth of these harmful fungus is to apply lime create land. Liming will help the beneficial bacteria in the soil grow like nitrogen fixing bacteria in legumes.
- Lime promotes the effect of organic matter, inorganic fertilizers and herbicides. Liming of organic matter decomposes faster, reducing organic poisoning in paddy fields; Lime helps keep humus (from decaying organic matter) from being washed away in lush orchards and in sandy soils, thus promoting the role of organic matter when it is supplied to the soil.
In alkaline soils, fertilizer applied to the soil is only about 30% useful, liming before fertilizing phosphorus, especially supe phosphate will increase the usefulness of phosphate. Liming also increases the usefulness of Moxide (Mo) and increases the potassium uptake (K) of the crop.
Herbicides belonging to the chemical group Triazine (Ametryn, Atrazine, ) and the sulfonylurea group (Bensulfuron Methyl, Cinosulfuron, Ethoxysulfuron, etc.) are more effective in liming.
Lime is one of the substances used to treat the environment is quite inexpensive but has many effects and efficiency is also very high, recommended for widespread use to improve ponds. Consumers are increasingly demanding the quality of food to be clean and safe. To do so, it is imperative that from production, shrimp farmers should avoid antibiotics and care and lip care. It is very important that fish and shrimp are not infected during the culture process. One of the most effective preventive measures for shrimp fish is the regular use of lime powder.
First of all, lime helps to lower the pH of soil and water, kill the pests, algae algae and pathogens in the pond. Lime helps the bottom of the pond waste is decomposed, the bottom of the pond better because of mineralization, water quality is improved, natural food of fish and fish from that richer. For shrimp culture, lime in ponds also have direct effects on shrimp in shell formation. However, too much lime should not be used as it may harm the environment and fish.
Lime has been used in hot mix asphalt (HMA) to reduce moisture sensitivity and stripping since 1910 in the United States. While hydrated lime has long been an acknowledged anti-strip additive for asphalt pavements, recent studies confirm that lime imparts other important benefits:
It stiffens the binder and HMA to resist rutting;
It improves toughness and resistance to fracture growth at low temperatures;
Lime changes oxidation chemistry in the binder to reduce age hardening; and
Lime alters clay fines to improve moisture stability and durability.
Lime is also useful to upgrade marginal aggregates. In addition to the chemical effects that lime imparts to reduce stripping potential and the aging impact resulting from oxidative hardening, the “filler effect” of lime improves resistance to high-temperature rutting and adds fracture toughness at low temperatures.
b) Building Construction
Lime has been used as a primary ingredient in masonry mortars for centuries, and this important use continues to the present day in both historic and contemporary applications. Mortars made with lime and cement exhibit superior workability balanced with appropriate compressive strength as well as low water permeability and superior bond strength. Lime is a major constituent in exterior and interior stuccos and plasters, enhancing the strength, durability, and workability of these finishes.
c) Soil Stabilzation
Lime can be used to treat soils in order to improve their workability and load-bearing characteristics in a number of situations. Quicklime is frequently used to dry wet soils at construction sites and elsewhere, reducing downtime and providing an improved working surface. An even more significant use of lime is in the modification and stabilization of soil beneath road and similar construction projects. Lime can substantially increase the stability, impermeability, and load-bearing capacity of the subgrade. Both quicklime and hydrated lime may be used for this purpose. Application of lime to subgrades can provide significantly improved engineering properties.