Nests periclase

Ono (1991) listed some of the characteristics of poorly burned clinker free lime greater than 4.5%, tightly packed large free lime nests, belite nests with a surrounding of small alites, high porosity, a loose framework of free lime and alkali aluminate, and a flow pattern of matrix into the free-lime nest. Well-burned clinker was said to contain small free lime and octahedral periclase from dolomite and coarse aluminate and ferrite, resulting from equilibrium crystallization. 

Lime nest with periclase Dolomite particle (Gille and others, 1965)... 

Periclase nest with free lime Coarse dolomitic limestone (Long, 1982a)... 

Open cluster of periclase plus free lime nest with interstitial periclase Large dolomite, depending on local surrounding chemistry (Fundal. 1980)... 

Cauliflowerlike calcium hydroxide crystals (presumably epezite), from hydration of free lime (air slaking), and round, gray periclase crystals in a nest, suggesting coarse dolomite in the feed. (S A6744)... 

A relatively "hard-to-burn" feed from the western U.S., with a very impure dolomitic limestone, has 6.7% >125 pm and an acetic-acid insoluble residue of 9.5% >45 pm, the latter comprised of quartz, feldspar, medium to finely crystalline igneous and metamorphic rock fragments, and an abundance of ferro-magnesian minerals (mainly amphiboles and pyroxenes). = 1.6% and = 4.5%. Belite nests (many with tightly packed crystals), solitary belite, and periclase are abundant in this fine- to medium-crystalline clinker. Nevertheless, a high-compressive strength mortar (44.8 to 48.3 MPa) is made, mainly because of the small alite size and the well-scattered solitary belite. 

Photograph 10-1 Kiln feed in thin section. Multicolored particles are grains of dolomitic limestone (calcite). Gray quartz at lower right, feldspar at upper right. Clinker produced contains an abundance of belite nests and periclase. (S A6869)... 

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