LIME

[:ru]Монастырев А. В.[:en]Monastyrev A. V.[:] [:ru]канд. техн. наук, Чаплыгин, Россия[:en]Cand. Eng. Sc., Chaplygin, Russia[:]

Alitinform №6 (17) 2010 г. 33-46 p.

Abstract

Russian Federation plants manufacturing building materials, soda and sugar produce lime by means of baking calcitic or slightly dolomitic limestone with the particles size of 50–150 mm in shaft furnaces. Metallurgical plants bake the lime with the particles size of 50–150 mm in shaft furnaces, and that with the particles size of 20–40 mm — in rotating kilns. As a result, hundreds million tons of limestone with the particles size of 0–20 mm and 0–40 mm are accumulated at quarries and at dumps of factories throughout the country.

Investigations carried out in research institutes, enabled to find out that it was possible to produce less expensive lime of high quality by means of processing limestone waste. As a result of processing, dispersed material with the particles size up to 2 mm is obtained, and this material is further baked in cyclone–vortex and cyclone furnaces. Quick burning of fine fraction or finely dispersed dolomite leads to production of lime not containing re–crystallized (over–burnt) МgО, which is suitable for manufacturing autoclave hardening products.

Quick burning of dolomitic limestone and dolomite in cyclone furnaces will enable to expand the raw materials basis for lime production in many regions of the country, and will enable to utilize carbonate raw materials for production of inexpensive and quality lime practically in full.

Russian and Ukrainian experimental–industrial cyclone furnaces have serious disadvantages in technical and economical parameters in comparison with the cyclone furnace from a Danish producer. Therefore, they require further improvement of the design, with the use of experience of foreign companies.

Key words:

calcium carbonate, magnesium carbonate, dolomite; lime: high–calcium, magnesian, dolomitic; shaft furnace, rotating kiln, cyclone furnace