RCRX 1074 tank car for hydrochloric acid service near Watford, ON February 20, 2011
Hydrochloric acid is a commonly produced industrial chemical that has applications in many chemical and industrial processes including steel making. In steel mills it is used to remove rust, scale and other surface impurities from finished steel.
While the car above was not photographed on the Algoma Central, it is representative of a common type of car in hydrochloric acid service. (Note that the Athearn 20,900 gal. RTC acid tank car is pretty much bang on for this prototype.) I did see a couple of similar SHPX cars at Hawk Junction, but didn’t get a good photo; I could also see some similar tank cars from a distance in Steelton yard from the Canyon Tour Train.
A related byproduct of using hydrochloric acid in the steelmaking process is the production of ferrous chloride as a waste product. This corrosive chemical has uses in water treatment systems, and a CN conductor friend of mine recently mentioned that he occasionally delivers a tank car of ferrous chloride from Sault Ste. Marie to the water treatment plant in downtown Toronto. Ferrous chloride (and related compounds like ferric chloride) is also shipped in tank cars of a similar size and design to hydrochloric acid.
ACFX 72346 tank car placarded for ferrous chloride at Sarnia, ON October 10, 2011
Photographed in the former ACR Steelton Yard in August 2004, ACFX 79202 is a good example of a clay slurry service tank car leased to Thiele Kaolin of Sandersville, Georgia.
Kaolinite is a natural occurring mineral often found in a clay form called kaolin. Shipped in either a dry powdered form or mixed with water to form a slurry, one of the primary uses of kaolin is coatings for glossy papers like those found in your favourite magazine. Before it closed down, the St. Marys Paper mill in Sault Ste. Marie produced such high quality papers for the American market, and tank cars of clay slurry would have been common around Sault Ste. Marie.
One interesting thing about the photo above is that all three leased cars visible here are built from different designs and builders. UTLX 300950 to the right was built by and leased from Union Tank Car; ACFX 79202 is built by and leased from ACF Industries while the unknown car to the left was built by Trinity Industries and possibly leased from either GATX, GE Railcar Services (NATX) or Trinity Leasing (TILX).