Patent US4547290A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4547290A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for solidification of strongly acidic or akaline liquid wastes

Assignee: Individual
•
Filing: 1984-05-02
•
Granted: 1985-10-15
•
Expires: 2004-05-02
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract According to the process, a clay material is first dispersed with stirring in the waste (or vice versa) between 0° and 150° C. then, in particular in the case of acidic wastes, it is neutralized to an approximately neutral pH by a product preferably with a lime base and, in a third phase, a hydraulic and/or calcium binder is added to the mixture. Application to petrification of all types of wastes of industrial, mining, urban and other origins.

Inventors

  • 👤 Philippe Pichat

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 02:05
CPC Classifications
C; C02; C02F; C02F11/00; C02F11/008; C04; C04B; C04B28/00; C04B28/02; C04B2111/00; C04B2111/00474; C04B2111/00767; C04B2111/00784; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91; Y10; Y10S; Y10S210/00; Y10S210/918; Y10S210/919

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 78 words
A process for the solidification of very acidic liquid wastes having a pH of less than or equal to about 2 or strongly basic liquid wastes having a pH of greater than or equal to about 12, into stable non-poluting solids which are resistant to leaching by water, consisting essentially of the steps of: mixing the very acidic or strongly basic waste liquid with a clay material; and then solidifying the mixture by adding hydraulic and/or calcium binder.
Claim 2
Dependent Claim 78 words
A process for the solidification of very acidic liquid wastes having a pH of less than or equal to about 2 or strongly basic liquid wastes having a pH of greater than or equal to about 12, into stable non-poluting solids which are resistant to leaching by water, consisting essentially of the steps of: mixing the very acidic or strongly basic waste liquid with a clay material; and then solidifying the mixture by adding hydraulic and/or calcium binder.
Claim 3
Dependent Claim 29 words
A process in accordance with claim 1, further including the step of, after said mixing step and prior to said solidifying step, neutralizing the mixture to approximately neutral pH.
Claim 4
Dependent Claim 25 words
A process in accordance with claim 2, wherein the waste liquid is very acidic, with a pH of less than or equal to about 2.
Claim 5
Dependent Claim 23 words
A process in accordance with claim 3, wherein said neutralizing step is accomplished by adding a mixture of basic waste material and clay.
Claim 6
Dependent Claim 39 words
A process in accordance with claim 2, wherein said neutralizing step is accomplished by the addition of an agent selected from the group consisting of quicklime, slacked lime, ground limestone, calcium carbonate base residues, calcium silicates and calcium aluminates.
Claim 7
Dependent Claim 49 words
A process in accordance with claim 2, wherein the waste liquid is strongly basic, with a pH of greater than or equal to about 12, and said neutralizing step is accomplished by adding acidic waste material or a mixture of acidic waste material with clay or coal fly ash.
Claim 8
Dependent Claim 25 words
A process in accordance with claim 1, wherein the waste liquid is strongly basic, with a pH of greater than or equal to about 12.
Claim 9
Dependent Claim 23 words
A process in accordance with claim 1, wherein said mixing step takes place at a temperature of about 0 to about 150° C.
Claim 10
Dependent Claim 45 words
A process in accordance with claim 1, wherein said clay material is selected from the group consisting of pure clay, a mixture of clays of the main mineralogical groups, technical clay wastes, wastes from quarries, wastes from the wash of clay sands, and mixtures thereof.
Claim 11
Dependent Claim 38 words
A process in accordance with claim 1, wherein the binder used in said solidifying step is selected from the group consisting of quicklime, slacked lime, Portland cement, blast-furnace slag, slag cement, coal or lignite fly ash and plaster.
Claim 12
Dependent Claim 32 words
A process in accordance with claim 10, wherein the amount of calcium binder added is such that there is a ratio of clay to Ca(OH) 2 of about 4 to about 25.

References Cited (Backward Citations)

US2679537A Cited
US3694356A Cited
US4116705A Cited
US4229295A Cited
US4149968A Cited
US4338134A Cited
FR2466564A1 Cited
US4375986A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-10-14 1989-04-15 1989-10-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-10-14 1993-04-15 1993-10-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-10-14 1997-04-15 1997-10-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag