Supply and processing of non-metallic minerals,Calcined lime  and Calcined Dolomite

Azar Sepeed Sepahan Production, Servicing, and Commercial Co. (Private Joint Stock) was established in 2006 and registered in Isfahan Companies Registration Bureau under registration No. 34210 as the producer of Calcined Dolomite, Calcined lime for the purpose of supply if requirements for steel and copper … industries in Iran and with the aim to procure and produce non-metallic minerals, Calcined lime, Calcined Dolomite, refractory clay etc. This company, having a land with the area of 5,000m2, is the largest producer of Calcined lime and Calcined Dolomite with the capacity of 120,000 tons of various types of products especially Calcined Dolomite and industrial lime, which is required by the steel industry. According to the orders, Azar Sepid Sepahan Co. is one of the suppliers of bauxite refractory and fire clay for the producers of castables, alumina, and bauxite refractory bricks with grade 70% as well as calcined magnesite for other industries.

Taking into account ever increasing growth of the mother industries in Iran especially steel industry as the major consumers of Calcined lime and Calcined Dolomite, raw material processing industry has a great position and importance. Fortunately, relatively satisfactory and acceptable improvements have been reached during these years in the field of producing non-metallic minerals like Calcined lime and Calcined Dolomite both from quality and quantity aspects and this is still continuing.

Increasing growth of our presence in the markets and simultaneously receiving ISO9001 global standard from DQS Germany has led to the quality optimization and increase in the market share by this company.

Through flexibility and strategic requirements, Azar Sepeed Sepahan Co. has passed numerous changes and this company is now considered to be one of the most successful suppliers of raw materials for Iranian steel industries and the same industry in Western neighborhoods.

Main consumers include:

  • Iron and steel industries
  • Copper industries
  • Sugar factories
  • Producers of hydrated lime

Specifications of Calcined lime and Calcined Dolomite production line kilns:

  • Rotary kiln No. 1 with the diameter of 3.4m by the length of 50m for the production of Calcined lime and Calcined dolomite
  • Rotary kiln No. 2 with the diameter of 1.8m by the length of 40m for the production of Calcined Dolomite and refractory clay
  • Rotary kiln No. 3 with the diameter of 3m by the length of 54m with 26m pre-heater in vertical mode for the production of Calcined lime and Calcined dolomite

quality certificate لوح تامین مواد خام اولیه تامین کننده برتر آهک صنعتی سال 91            
تولید کننده دولومیت کلسینه
تولید کننده آهک کلسینه

Services and Policy

Quality assurance policy of Azar sepeed Sepahan Co., producer of calcined lime and calcined dolomite

Policy and general targets of Azar sepeed Sepahan Co., producer of non-metallic minerals ( calcined lime and calcined dolomite) concerning quality are as follows:

To identify and realize customers’ requirements and demands and to attract their satisfaction, to make progressive efforts for the supply of calcined dolomite and calcined lime as well as the services based upon the specifications agreed with customers, on-time delivery of the products with the most suitable prices, and to increase customers’ certainty about supplied products and services

To increase staff’s skills and proficiency through identifying and supplying their training requirements, quality and efficacy optimization by means of strategic planning, to clarify organizational targets, duties, responsibilities, and internal relationships between organizational members, to grant authorities to the members, to attract their partnership, applied development and responsibilities

Obviously, reaching the above targets require personal and collective commitments by the whole workers in all the levels and departments of this company.

Wish all the colleagues ever increasing success towards making a safe, healthy, and pleasant working environment.  


بارگیری دولومیت کلسینه
بارگیری آهک کلسینه


Calcined Lime

Calcined Lime

Calcined Lime is being made through burning Limestone under 1000-1200°C. Rotary, vertical, or rotary-vertical kilns are applied for the industrial lime burning. Limestone is being kept in the kilns at least for 2:30-3 hours. Therefore, the more it takes burning, the quality of produced lime (Calcined Lime ) will be improved. In addition, Azar Sepid Sepahan Company has been recognized as one of the outstanding companies producing high quality lime and Calcined Lime through having kilns with 3m diameter and 55m length with 26m preheater.


Chemical analysis Calcined Lime table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
4-6 0.1-0.3 0.5-1.5 90-93 0.3-0.5 0.5-1.5 Trace Trace Trace Trace Trace


The main mineral constituent in lime is called “Calcite” with the chemical formula CaCo3. Carbonate calcium is the equivalent. Limestone or carbonate calcium is rarely found in the form of pure lime in the nature. This stone is mostly seen in the form of Clay-line, sand-lime, and dolomite. The important impurities in Limestone include: magnesium, silicon dioxide, aluminum, and manganese. Limestone is burnt in the kiln under suitable temperature with a specific chemical composition. Pure Limestone and clay-Limestone or dolomite are being calcined under 1000°C and 1300°C, respectively. Hydrated lime is also called “quick lime” or CaO. This kind of lime is not stable in air and humidity and cannot be maintained for a long time. Carbonate calcium in the Limestone has to be more than 90% and he relevant SiO2+Fe2O3+Al2O3 content must be less than 4% for the production of CaO. Limestone is being burnt in horizontal or vertical kilns. Steel industry: before 1960, lime used to be applied in open kilns in steelmaking process along with other matters. Amount of consumed lime for the production of one ton steel is around 12kg. From 1960 till date and upon introducing Basic Oxygen Furnace (BOF) methods, only lime is being used as the consumed amount is increased to 50-100kg/t. amount of consumed lime for the steel industry has increased from 1.4 million tons in 1961 to 8.1 million tons in 1979. Carbonate rocks: A mixture of calcium and non-carbonated base is considered to be the major carbonated rocks maker. This composition is appeared in the form of different minerals. The main contents include calcite (CaCo3), dolomite (Ca, Mg, CO3), and other types like siderite and ankerite. Additionally, Azar Sepeed Sepahan Co. has guaranteed calcination of the company both quantitatively and qualitatively upon owning one of the best Limestone mines 25km far from the factory.


Chemical analysis Limestone table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
43-45 0.05-0.07 0.5-1 53-56 0.01-0.03 0.05-0.8 Trace Trace Trace Trace Trace

Calcined Dolomite

Calcined Dolomite

Ideally, dolomite is made of Ca2+ and Mg2+ equal ions that have been separated in order by CO+. A good ordered formation of dolomite will cause some kind of ultra-structural reflections in X-ray Diffractometer (XRD), which is somehow structurally different with calcite. Most of the present dolomites have a lower order degree in comparison with older ones. “Protodolomite” is made for Ca-Mg carbonates that have been introduced in the laboratory with a very low/no reflection order. Fe replacement in dolomites is frequent and Fe-contained dolomite is being formed with a few FeCO3 percentages, which may follow with Ankrite. Primary dolomite: The word “primary” is mostly applied for a kind of dolomite that refers to the direct sedimentation of sea or lake water. In fact, most of the dolomites are being made through replacement in carbonated minerals that have been formed before. However, dolomite cements are also available. Classification of carbonated stones as per dolomite content: • Limestone: A kind of stone containing 0-10% dolomite. • Dolomite Limestone: A stone containing 10-50% dolomite. • Calcined Dolomite: A stone containing 50-90% dolomite. • Dolostone: A stone containing 90-100% dolomite. Calcined Dolomite is being made through burning dolomite stone under 800-1100°C such that it has minimum 2:30-3 hours stability under 1000°C. Sintering dolomite: This kind of dolomite is being made through burning dolomite stone under 1650-1800°C and is applied for the production of refractory bricks and dolomite mortars. Owning four kiln sets, Azar Sepeed Sepahan Co. has been recognized among the main producers.


Chemical analysis Calcined Dolomite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
4-6 0.1-0.3 35-40 50-55 0.5-1.0 0.5-1.5 Trace Trace Trace Trace Trace

Raw Dolomite

Raw Dolomite was introduced for the first time by a French geologist “Dolomieu” in 1791, which was applied for the Raw Dolomite Mountains in southern Tyrol and afterwards it was called Raw Dolomite. Raw Dolomite is calcium and magnesium carbonate that is the combination of calcite and megnesite with the chemical formula of CaMg(Co3)2. Dolomites have various applications in metallurgy industry, production of Raw Dolomite refractory bricks, glass, and ceramic industries according to the MgO content and impurities in the Raw Dolomite stone. In addition, Azar Sepeed Sepahan Co. has guaranteed future calcination of the company upon having one of the best mines in 22km far from the factory.


Chemical analysis Raw Dolomite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
44-46 0.05-0.07 20-21 30-32 0.2-0.4 0.5-0.9 Trace Trace Trace Trace Trace
Raw Dolomite
Fluor spar( Flourite)

Fluor spar( Flourite)

This mineral is available in yellow, green, pink, blue, purple, no-color, and sometimes black, which is being crystallized in cubic system. Fluorine is semi-transparent with glass shining. The special weight of this mineral is 18.3 with the hardness of 4. Fluorine or flourite (CAF2) is the most important Fluorine mineral in the nature, of which Fluorine is being extracted. Fluorine usually fills the empty space between other minerals and mostly it is found in the nature in the form of veins following with calcite, quartz, barite, Celestine, and various sulfides. Fluorine, in case of purity, contains 48.7% and 51.3% calcium. Formation, reservoir, and production of FluorineFluorine is being formed and observed in a wide area of geological conditions. Fluorite ore may have sediment –carbonated origin or the vein form normally related to the acid igneous stones. As per the data of Ministry of Industries & Mines, totally more than 3.1 million tons of approximate reservoir and more than 1.5 million tons of definite reserve for Fluorine existed in Iran in 2001.


Chemical analysis Fluor spar( Flourite) table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
3-5 0.2-0.5 2-4 Trace 0.05-0.9 2-4 Trace Trace Trace 9-11 77-79


Bentonite is a kind of fine clay and is normally referred to colloide organic soils that is mixed with Cretaceous Benton Shale near Benton Army Castle and Rock River, Wyoming. Bentonite is a matter under clay or semi-clay category and is formed by swelling minerals that generally contain montmorillonite and a little Beidellite. As such, Bentonite is a clay with 85-90% montmorillonite. The word “montmorillonite” is derived from a place in the south of France named Mountmorillon that is a rich source of Bentonite. Many of the bentonites are formed as the result of weathered volcanic ashes and mostly with the presence of water. Their stone origin is basic. Volcanic ashes are mostly created in salty and wetlands. As we move farther from the volcano, Bentonite thickness will decrease. Bentonite has an alumina-silicate structure and therefore it is categorized under 3-layered silicates. Bentonite has two tetrahedron and one octahedron layers. Calcium Bentonite is applied for casting sand, oil absorbents and grease, filtration and refinery, and livestock feed.


Chemical analysis Bentonite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
Trace 10-13 Trace 3-5 3-4 60-70 Trace Trace Trace Trace Trace


 Diatomite is a soft siliceous sedimentary rock formed by the accumulation of the amorphous silica (opal, SiO2•nH2O) remains of dead diatoms (microscopic single-celled algae) in lacustrine or marine sediments. The fossil remains consist of a pair of symmetrical shells or frustules. Lexically, “Diatomite” or “Diatomite soils” are the same. Muller is also a kind of Diatomite soil with plastic clays. Tripoli is the synonym for Diatomite, but Tripoli is some cases is a kind of fine silicate sediment that is applied as a grinder and it has no plant origin. In some regions in Libya and Algeria (near Tripoli port), Diatomite is mistakenly called Tripoli. In addition, “meerschaum” is sometimes used to describe Diatomite that is in fact a type of clay with fossil origin. Diatomite is basically applied as a kind of filter for the separation of suspended solids in liquid. In fact, more than 50% of Diatomite is applied. Diatomite is also used as a filter for different filtration industries including sugar factory, medicine filtration, alcohol drinks, raw sugar matter, antibiotics, urban water, swimming pool water, fruits, jet airplane fuel etc. The second major application of Diatomite is the filling matter in paint industry, papermaking, and grinders. Diatomite is used as the filler in paints in order to control transparency and shining. Another interesting issue about Diatomite is the low volumetric weight. As such, Diatomite is applied in those industries that require low volumetric weight in addition to the carton making industries in which Diatomite creates layer strength.


Chemical analysis Diatomite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
Trace 3-4 0.1-0.3 0.5-0.9 1-1.5 89-92 Trace Trace Trace Trace Trace

Sinter Magnesite

Sinter Magnesite is gained through magnesite rock that this company is ready to cooperate with consumers as per the orders of more than 200 tons. In addition, Azar Sepeed Sepahan Co. is able to produce high quality Sinter Magnesite through having rotary kilns with 80m and 50m lengths.


Chemical analysis Sinter Magnesite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
Trace 0.1-0.4 88-90 3-4 0.3-0.9 5-7 Trace Trace Trace Trace Trace
Sinter Magnesite
Raw Magnesite

Raw Magnesite

The word “Magnesite” might have been derived from its chemical composition. Some believe that the name is originated from Magnesia region in Greece. The relevant chemical formula is MgCo3. Crystallization system: Hexagonal, Trigonal (a kind of calcite) The appearance of crystals is mostly like pile, strings, or sometimes compressed or grain shaped. Color: White, white turning to gray, yellow or brown (like plaster) Raw Magnesite is boiled with hot acid and creates foam. As one of the consumers of Raw Magnesite Rock, Azar Sepeed Sepahan is ready to cooperate for calcination upon orders.


Chemical analysis Raw Magnesite table

L.O.I Al2O3 MgO CaO Fe2O3 SiO2 Na2O K2O TiO2 CaCO3 Caf2
50-52 Trace 44-46 1-2 0.4-0.8 1.5-3 Trace Trace Trace Trace Trace



Esfahan, Iran

Centeral Office : Esfahan - Iran

P.O.BOX : 81645-583

Phone : +98 313 6617540

Fax : +98 313 6617541


Factory : Shahreza - Esfahan - Iran