Liquid purification or separation – Processes – Making an insoluble substance or accreting suspended...
Patent
1985-11-12
1987-04-14
Hruskoci, Peter
Liquid purification or separation
Processes
Making an insoluble substance or accreting suspended...
55 53, 55 70, 210718, 210724, 210726, 210903, 210906, 210915, 423321R, C02F 120, C02F 152
Patent
active
046576800
ABSTRACT:
A method is provided for the treatment of wastewater of pH ranging from about 1.5 to 3 containing at least about 100 ppm phosphorus as phosphate ions, at least about 50 ppm fluorine as fluoride ions and ammonia in excess of about 15 ppm NH.sub.3 (N)--T, the method comprising removing the phosphate and fluoride ions from the wastewater in a two-stage precipitation step; the first stage precipitation being conducted at a pH ranging from about 3.5 to 6.5 using an alkaline material selected from the group consisting of limestone (CaCO.sub.3) and lime [CaO or Ca(OH).sub.2 ] sufficient to form a precipitate which is removed to provide a filtrate of the wastewater which is treated in a second stage precipitation at a pH of at least about 10.5 using lime as the alkaline material sufficient to form a precipitate which is removed to provide substantially a clear effluent containing ammonia. The method also includes, if necessary, treating the ammonia-containing effluent with an alkaline material selected from the group consisting of lime and caustic sufficient to raise the pH to provide a free ammonia equivalence (FAE) of at least about 12.4; the free ammonia equivalence being determined as follows:
REFERENCES:
patent: 3551332 (1970-12-01), Baumann
patent: 3725265 (1973-04-01), Legal
patent: 4045341 (1977-08-01), Tsuruta et al.
patent: 4093544 (1978-06-01), Ross
patent: 4306978 (1981-12-01), Wurtz
patent: 4320012 (1982-03-01), Palm et al.
Mooney et al., "Removal of F & P from H.sub.2 PO.sub.4 Wastes with 2-Stage Lime Treatment," Ind. Wastes Conf., Purdue University, 1978, pp. 286-295.
Culp et al., Handbook of Advanced Wastewater Treatment, 2nd Edition, Von Nonstrand Reinhold Company, pp. 298-316.
Williams, Waste Production & Disposal in Mining, Milling & Metallurgical Industries, Miller Freeman Publications, 1975.
Process Design Manual for Nitrogen Control, U.S. EPA, Oct. 1975.
Amax Inc.
Ciomek Michael A.
Hruskoci Peter
Kalil Eugene J.
LandOfFree
Wastewater treatment does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Wastewater treatment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wastewater treatment will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1783788