Ronald James McLaughlin
Engineers in Arvada, CO
License number
Utah 8434328-2202
Issued Date
Oct 11, 2012
Expiration Date
Mar 31, 2017
Category
Engineer/Land Surveyor
Type
Professional Engineer
Address
Address
Arvada, CO
Professional information
Process For Removing Heavy Metals From Water
US Patent:
5266210, Nov 30, 1993
Filed:
Apr 15, 1992
Appl. No.:
7/869239
Inventors:
Ronald J. McLaughlin - Arvada CO
Assignee:
McLaughlin Water Engineers, Ltd. - Denver CO
International Classification:
C02F 162
US Classification:
210710
Abstract:
Wastewater contaminated with heavy metals is treated in a multi-stage process. In a first stage, wastewater is treated with an effective amount of calcium oxide and/or calcium hydroxide in the form of lime to adjust the pH so that various metals in the water become insoluble. Gypsum formation may also occur if sulfate ions are present in the wastewater. In a second stage, an effective amount of sodium carbonate is added in the form of soda ash to allow formation of calcium carbonate. In a third stage, a coagulant, preferably a polymer, is added to facilitate the formation of a sludge comprising heavy metals, gypsum and calcium carbonate. In a final stage, the pH of the resulting effluent may be adjusted with a suitable acid, such as hydrochloric acid, to attain acceptable discharge requirements. The sludge formed is substantially stable and dewatered and has low toxic metal leaching characteristics.