A lime kiln from a limestone quarry is preserved in the Keepataw County Forest Preserve. The official parking lot is on top of the river bluff. To see this kiln, you need to park in a picnic area off Bluff Road and walk to the Veterans Memorial Trail and go south under I-355.
|20140820 0035 taken from Veterans Memorial Trail|
The Keepataw site is significant both for its association with the giant Western Stone Company and its long-time president, Martin B. Madden, and for what it can reveal about large-scale turn-ofthe-century limestone quarrying and processing operations. Between 1889 and 1918, the Keepataw site was part of the vast holdings of Western Stone, "the largest company of its kind in America."1 This giant combine of six important Des Plaines Valley quarrying companies was formed in 1889, just as local limestone was being supplanted as a building material by Indiana Bedford limestone and various stone substitutes....By 1920, the company had long since ceased active operation.The quarry was served by the Chicago Santa Fe & California Railway (an ATSF subsidiary).
|1940 Aerial Photo from ILHAP plus Paint|
|Satellite plus Paint|
Quarrying companies also often maintained on-site facilities for the production of lime, a limestone by-product used in making mortar and portland cement, among other things. Lime is derived from limestone by heating the stone to between 900 and 1,000 degrees, and thereby freeing carbonic acid gas (carbon dioxide).
Commercial lime burning has long been done in permanent structures known as lime kilns. In the late nineteenth and early twentieth centuries, lime kilns were of two general types: intermittent kilns and continuous kilns. Intermittent kilns needed to be cooled and reloaded between each burning. Continuous kilns, as their name implies, could be fueled and loaded without interruption.
Continuous kilns fell into three sub-categories: mixed feed, separate feed, and rotary kilns. Mixed feed kilns were so named because limestone and fuel were charged into the kiln in alternate layers. One type of mixed feed kiln, dubbed by Grimsley in 1906 as the "old type," were square stone "pot" kilns. Grimsley described these as 18 to 20 feet high and 10 to 12 feet square. These kilns were fired with coal, although a wood fire was built at the bottom to start the lowest layer of coal burning. As the fire gradually worked its way up the kiln, the burned lime was removed and new layers of coal and limestone were fed from the top. According to Grimsley, "the kilns [were] cheap in construction, the process of burning [was] simple, and the lime [was] usually of good degree of strength, but [was] apt to be dark in color."
The separate feed kiln type, which by 1905 was said to be "used at most of the larger lime-burning plants," comprised a wide variety of patent kilns.103 In general, these kilns, rising 25 to 35 feet, were taller than the mixed feed kilns. Most were sheathed in steel or iron and lined with fire brick, although some were constructed of stone. The limestone was charged from the top, as in mixed feed kilns. The fuel, however, was burned in separate furnaces located either inside or outside the wall of the kiln. Thus, the limestone was burned by the hot furnace gases, rather than by the fuel itself. As in the mixed feed kilns, the burned lime was removed from the bottom of the kiln. One typical separate feed kiln, the Keystone kiln, was raised above the ground so that the burned lime could be discharged from the bottom of the kiln directly into small rail cars running beneath it.