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Licensed for the sole use of the purchaser.See license agreement penalties for distribution. CGA G-1.5-2015 COMPRESSED GAS ASSOCIATION INC. PAGE 3 5.2 Percent solids versus available calcium oxide The available calcium oxide content of carbide lime is a useful comparative index of its value. Although there is no calcium in the form of the oxide present in the carbide lime, the available CaO can be calculated from the available calcium hydroxide. Table 2 shows the approximate volume and weight of slurry containing a ton of available lime for various solids. Table 2—Percent solids versus available calcium oxide Solids content gal carbide time slurry/ Ib carbide lime slurry/ % ton available CaO ton available CaO 10 3 300 28 800 20 1 560 14 600 30 960 9200 40 670 7200 50 510 5 800 60 400 4 800 5.3 Typical analyses Table 3 shows typical chemical analyses of carbide lime. Note that all values with the exception of moisture are presented on a dry basis, meaning they are calculated with the water removed. Table 3—Typical lime composition Component Carbide lime slurry Carbide lime storage Commercial impoundment hydrated lime Available calcium hydroxide-Ca(OH)2 88%to 94% 78%to 84% 91.6%to 94.3% Available calcium oxide equivalent 66%to 71% 59%to 64% 69.9%to 71.4% Carbonate as CaCO3 1%to 2% 5%to 15% 2.1%to 4.0% Silicon expressed as Si02 2.0%to 3.0% 1.5%to 2.5% 0.8%to 1.3% Iron and aluminum expressed as R203 1.8%to 2.3% 1.5%to 2.0% 0.4%to 0.9% Magnesium as MgO 0.01%to 0.02% 0,01%to 0.02% 0.5%to 1.3% Free carbon 0,5%to 1.5% 0.5%to 1.5% — 5.4 Advantages of carbide lime 5.4.1 Complete hydration Carbide lime produced with the wet process is manufactured with a large excess of water, which ensures its complete hydration. Commercial hydrated lime is shipped as a dry product and made with a limited amount of water to minimize drying costs. Thus it may be slightly less hydrated than carbide lime. 5.4.2 Fine particle size The small particle size is caused by the nature of the carbide lime formation from calcium carbide. Acetylene on liberation has a tendency to crack or break open ordinary fine grains of lime into still finer particles. Advantages of fine particle size are faster and more efficient reactivity and the need for a smaller amount of carbide lime than ordinary hydrated lime. This is particularly valuable when carbide lime is used in chemical, industrial, and construction applications. The small amounts of ferrosilicon and free carbon in carbide lime can be removed by screening the slurry. This material can be marketed separately or discharged with appropriate regulatory ap- provals. Typical carbide lime particle sizing found in slurries is as follows: – plus 80 mesh-0%to 5% This document licensed for the sole use of the purchaser. It may not be shared with any other person or used after the expiration date without the express written permission of the CGA Any unauthorized use, reproduction, distribution, or modification of this printed page will result in a$5,000 liquidated damages fee plus loss of access to CGA publications for one year for your company.