Rotary kilns are used to heat solid materials to a temperature high enough to induce a chemical reaction. A rotary cement kiln, refractory rotary kiln and rotary alumina kiln are common examples of the equipment. Other applications include waste lime recovery, thermal desorption of organic and hazardous wastes, mineral roasting, specialty ceramics, plastic processing, gypsum calcining, tire pyrolysis, bauxite calcining and phosphate productions.

Rotary kilns are cylindrical and rotate on an axis. They are slightly inclined and the material moves toward the lower end of the kiln as it is rotated. Hot gases move either with the material, or more commonly, against it. The gases are generated by an external furnace or a flame within the kiln. Rotary kilns use a refractory lining to protect the kiln shells from the extreme temperatures. When purchasing a rotary kiln, consider the following:

1. Use rotary kilns that are designed specifically for the material you're processing.

2. Purchase custom rotary kilns for a design based on your specifications.

3. Lower rotary kiln prices with used kilns and replacement parts.

Action Steps
The best contacts and resources to help you get it done

Find application-specific rotary kiln design

Purchasing a rotary kiln designed specifically for your application ensures your equipment functions properly and efficiently. Materials need to be retained in the kiln for various amounts of time. The kiln's diameter, length, speed, slope and internals design determines the solids-retention time.

I recommend: FLSmidth Minerals supplies rotary kiln to the minerals industry. The manufacturer's kilns are designed for processing alumina, bauxite, copper concentrate, lightweight aggregate, lime sludge, limestone and phosphate. Order application-specific rotary kilns from Metso Minerals. The rotary kiln supplier offers both direct- and indirect-fired rotary kilns.

Order from custom rotary kiln manufacturers

Custom rotary kiln manufacturers design and fabricate rotary equipment based on your specifications. When ordering a custom rotary kiln, consider the kiln's size, material and heat ability required for your application.

I recommend: Order a custom rotary kiln from Boardman. The custom manufacturer fabricates industrial rotary kilns from a variety of materials, including carbon steels, nickel, stainless steel and high nickel alloys. FEECO fabricates rotary kiln systems for both heat absorbing and heat liberating processes.

Reduce rotary kiln prices with used equipment and replacement parts

Ordering used rotary kilns decreases your equipment cost. Used replacement parts are also a cost-effective way to maintain your rotary kiln. Good parts are often stripped from defective kilns and sold at a discount. Keeping common replacement parts in-house reduces down time during maintenance.

I recommend: Browse an inventory of new and used rotary kiln parts at Rotary Kiln & Dryer. The company designs and manufactures rotary process equipment for agricultural, mineral processing, chemical, petro-chemical, and food processing industries. Order rotary kiln dryer replacement parts from Rotary Service Company. The company also offers field rotary kiln maintenance. Machinery & Equipment Company supplies used rotary kilns to many processing industries, including cement, paper, metals, mining, and chemical.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  When purchasing rotary kilns, you must also buy material exit hoods, which connect to the lower end of the kiln. The material exit hood collects waste gases, which can then enter a pre-heater to exchange heat with the entering feed.