The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 31, 2001
Filed:
Jul. 15, 1999
Yuji Wada, Kanagawa, JP;
Kenichi Ikeda, Kanagawa, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a fluoride including waste water processing device which comprises a reaction vessel and a sedimentation vessel, a calcium compound adding device adds calcium compound in fluoride including waste water in the reaction vessel to react the calcium compound with fluoride of the fluoride including waste water to generate calcium fluoride. The sedimentation vessel has a bottom which is associated with a bottom of the reaction vessel through an opening hole. The fluoride including waste water is sent to the sedimentation vessel from the reaction vessel through the opening hole. The sedimentation vessel has an inclined bottom surface. The calcium fluoride is sent back, by a self-weight of the calcium fluoride, to the reaction vessel from the sedimentation vessel along the inclined bottom surface. An agitator aggregates the fluoride including waste water in the reaction vessel. A polymer solution adding device adds polymer solution in the fluoride including waste water in the reaction vessel. A supernatant liquid draining device drains supernatant liquid of fluoride including waste water from the sedimentation vessel.