Horizontal rotary kilns

Firebrick Insulating Lightweight Firebrick Insulating Castable 

There are a number of designs that can be used, but generally the magnesia industry utilizes a directly fired kiln using an internal burner. Firing temperatures can be as high as 3000°F with residence times of 3-6 h. Kilns can have internal adaptations that help improve the efficiency of the calcinations process. These include  

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Cement plants with horizontal rotary kilns... 

Haloclean A pyrolytic process for destroying scrap plastics, especially those derived from scrap electronic equipment. The material is passed through a horizontal rotary kiln containing metal spheres that aid the heat transfer. Developed in Karlsruhe, Germany, and piloted from 2006. 

Kilns. Reactions involving free-flowing solid, paste and slurry materials can be carried out in kilns. In a rotary kiln, a cylindrical shell is mounted with its axis making a small angle to the horizontal and rotated slowly. The solid material to be reacted is fed to the elevated end of the kiln and it tumbles down the kiln as a result of the rotation. 

The rotary kiln is simple in concept, but difficult to operate in practice. The rotary kiln is a refractory lined, steel cylinder mounted horizontally on trunions and riding rings. It is pitched slightly toward the discharge end to facilitate material flow through the kiln. The kiln is fed from the high end and can be fed either whole tires or TDF chips. It can be fired internally or heated externally. 

The rotary kiln is a long tube that is positioned at an angle near horizontal and is rotated. The angle and the rotation allow solid reactants to work their way down the tube. 

Calcination can also be carried out continuously in a rotary kiln of the type shown in Fig. 3.1. This consists of a slowly rotating tube mounted with its axis at an angle to the horizontal such that powder fed in at the top emerges at the bottom in the desired state. Heat is usually supplied by the combustion of oil or gas inside the barrel. 

Indirectly heated, horizontally arranged, rotary kiln for Thermal Desorption and low temperature carbonisation of the 0 5 mm input basic material, containing the following technical characteristics ... 

Indirectly heated horizontally arranged rotary kiln equipment is used for low ten erature carbonization. 

Screw conveyor and indirect rotary. Indirect type, continuous operation. Includes paddle, horizontal agitated and steam-tube dryers, rotary kilns. Applicable with dry-product recirculation Applicable with dry-product recirculation Generally requires recirculation of dry product. Little dusting occurs. Chief advantage is low dust loss. Well suited to most materials and capacities, particularly those requiring drying at steam temperature Low dust loss. Material must not stick or be temperature-sensitive Not applicable Not applicable Not applicable... 

FIGURE 7.1 Details of operation of a rotary horizontal lime kiln. Temperature of calcium carbonate charge rises as it moves down the kiln. The hot calcium oxide, as it cools, is used to simultaneously preheat the firing air. Fuel may be natural gas or oil. 

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