Soda ash improves lead removal in lime precipitation process

Conference · Fri Jan 01 00:00:00 EST 1982 · Proc. Ind. Waste Conf.; (United States)

OSTI ID:5178867

Hsu, D Y ^[1]; Riddell, M D.R.; Bonamico, B

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1. Greeley and Hansen, Chicago, IL

Both laboratory-scale and plant-scale studies were conducted to evaluate the feasibility of using soda ash as a supplemental chemical in the existing lime neutralization-sedimentation process. The purpose was to improve the efficiency of lead removal from a metal finishing wastewater by taking advantage of the lower solubility of lead carbonate. Plant-scale studies indicated that addition of soda ash at about 2 mg Na/sub 2/CO/sub 3/ per mg Pb and at a pH between 8 and 11.5 reduced lead content in the settled effluent consistently to less than 0.3 mg/l. This is considerably lower than the 0.5 mg/1 specified in the sewer use ordinance. After about one year's operation, this modified lime neutralization-sedimentation process has been found to be more stable and reliable, and requires less attendance than the simple lime process. The process can also now be operated at a lower pH (minimum: 7.0) with the addition of soda ash, which has resulted in a lower amount of sludge production, lower lime usage and significantly lower manpower requirements.

• OSTI ID: 5178867
• Report Number(s): CONF-810577-
• Journal Information: Proc. Ind. Waste Conf.; (United States), Vol. 36; Conference: 36. annual Purdue industrial waste conference, Lafayette, IN, USA, 12 May 1981
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
LEAD
REMOVAL
WATER POLLUTION CONTROL
ADDITIVES
EFFICIENCY
PH VALUE
SEDIMENTATION
SODIUM CARBONATES
WASTE PROCESSING
WASTE WATER
ALKALI METAL COMPOUNDS
CARBON COMPOUNDS
CARBONATES
CONTROL
ELEMENTS
HYDROGEN COMPOUNDS
LIQUID WASTES
MANAGEMENT
METALS
OXYGEN COMPOUNDS
POLLUTION CONTROL
PROCESSING
SODIUM COMPOUNDS
WASTE MANAGEMENT
WASTES
WATER
520200* - Environment
Aquatic- Chemicals Monitoring & Transport- (-1989)