Light-burning

Transportation of natural gas through pipelines began in the United States in the early part of the nineteenth century. One of the first known uses occurred in 1821 with the building of a system of metallic lead pipes to transport natural gas from a nearby shallow well to commercial establishments in Fredonia, New York, Gas lights—burning gas made from coal—illuminated the streets of Baltimore beginning in 1816. 

When a carbon arc light burns in air, the radical CN is formed. The spectrum of the arc shows two strong absorption bands at about 9000 cm-1 and 26,000 cm-1. 

A light burned in her room, for she never sleeps in complete darkness—unless her current companion insists on it, I suppose—and I could see that she was alone. She stirred while I was undressing. 

Miraculous and numinous visions, pillars of light, burning... 

Mohr s White Fire, which is very effective and scarcely ever misses fire, is composed of 24 parts of saltpetre, 7 of sulphur, and 1 of fine charcoal. The charcoal increases the inflammability of the mixture and shortens the length of time during which the light burns, but adds to its intensity. It is not permissible to use a larger amount of cnar coal than that given, as the composition, would then approach thatof gunpowder. 

Materials Colour zoning Inclusions Sectility In salt water UV light Burning aroma... 

When the gas is turned on, the current of gas draws air through the holes at the bottom of the tube, and this mixture, when lighted, burns with an almost colorless, i.e. non-luminous, flame. It is a hot flame and deposits no soot. The burner... 

The production of chemical-grade magnesia or light-burned MgO requires careful control of the calcination temperature to achieve the required specific surface area of the finished product. A furnace well suited to this requirement is the multiple-hearths Herreshoff-type. For the production of dead-burned magnesia typically shaft or rotary kilns are employed. See Chapter 5 for furnaces used in MgO production. 

Light-burning, in which the temperature is kept between 700°C and i,ooo°C (i,5oo°F and 2,ooo°F), resulting in a product with even more reactivity and... 

Porosity. Part of the porosity of particles of commercial quicklime arises from the porosity of the limestone, and part from the decomposition process. The porosity of conunercially produced quicklime can be as high as 55% (by volume), when a porous limestone is lightly burned. Exposure to elevated temperatures results in sintering (see sections 15.4 and 15.5), which can reduce the porosity to below 25 %. Dead-burned dolomite has a porosity of about 10 %. 

The fuels used in the various designs of modern shaft kilns currently available (see section 16.8) are selected to produce medium to light-burned lime, at high thermal efficiencies, without the emission of dark smoke. All designs can use natural gas, most can also use fuel oil and some can operate on pulverised solid fuel. 

Thus the properties of quicklime from a given kiln reflect the average properties of individual lumps, each of which has experienced a particular time-temperature history. Fig. 15.8 compares the distribution of particle densities for a light-burned quicklime from an annular shaft kiln, with a mean apparent density of 1.66 g/cm with that of a solid-burned quicklime from a coal-fired traditional shaft kiln with a mean apparent density of 2.15 g/cm. Table 15.4 presents some typical... 

Much of the lime from shaft kilns was still hand-picked to remove partially calcined lumps (which were tipped), and to sort light-burned from solid-burned lime. 

Light-burned dolomite (or dolime) is produced in either rotary or shaft kilns. The principles are similar to those of making high calcium quicklime. Heat usages are presumably somewhat lower, owing to the lower heat of calcination of dolomite and its lower dissociation temperature. 

Some very light-burned dolomitic limes are hydrated at atmospheric pressure in a similar way to high-calcium limes. They use maturing bunkers to provide 12 to 24 hours of residence at 80 to 90 °C in the presence of excess water. 

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