Process for solidifying organic and inorganic provisional constituents contained in produced water from heavy oil operations

1. A method for treating produced water recovered from a oil recovery process comprising:

collecting an oil-water mixture from an oil bearing formation;

separating oil from the oil-water mixture to yield produced water comprising water, organics, and dissolved solids;

directing the produced water into a crystallizer;

concentrating the produced water by heating the produced water in the crystallizer and removing water from the produced water and producing a vapor and an organic melt containing solid crystals; and

cooling the organic melt such that the organic melt solidifies into an organic solid structure containing the solid crystals, and wherein substantially no free water is present in the organic solid structure.

2. The method of claim 1 wherein concentrating the produced water comprises concentrating the produced water to a total solids concentration of 75% to 85% by weight.

3. The method of claim 2 wherein heating the produced water comprises heating the produced water to a temperature of approximately 100° C. to approximately 120° C.

4. The method of claim 3 wherein cooling the organic melt comprises cooling the organic melt to a temperature of approximately 20° C. to approximately 30° C.

5. The method of claim 1 wherein after cooling, the organic solid structure has a compressive strength of approximately 3,500 kg/m 2 or higher.

6. The method of claim 1 further comprising blending fly ash into the organic melt prior to forming the organic solid structure.

7. The method of claim 6 wherein blinding fly ash comprises adding fly ash to the organic melt at a ratio of approximately 1 to 2 or 1 to 1.

8. The method of claim 1 wherein the produced water includes a relatively high concentration of sodium chloride relative to the concentration of non-sodium chloride inorganic solids in the produced water, and wherein concentrating the produced water causes the sodium chloride to precipitate from the produced water and form sodium chloride crystals; and wherein after cooling the organic melt, the sodium chloride crystals are contained in the organic solid structure.

9. The method of claim 1 further comprising adding calcium chloride to the organic melt prior to forming the organic solid structure.

10. The method of claim 9 wherein adding calcium chloride comprises adding between 0.5% to 4.0% by weight calcium chloride to the organic melt.

11. The method of claim 1 further comprising coating the organic solid structure.

12. A method of recovering oil from an oil well and treating produced water, comprising:

(a) recovering an oil-water mixture from the oil well;

(b) separating the oil-water mixture to produce an oil product and the produced water that includes dissolved inorganic and organic solids;

(c) concentrating the produced water in an evaporator to produce a distillate and evaporator blowdown wherein the evaporator blowdown includes dissolved inorganic and organic solids;

(d) directing the distillate to a steam generator and producing steam;

(e) injecting the steam into an injection well which gives rise to the oil-water mixture in the oil well; and

(f) directing the evaporator blowdown to a crystallizer and

(i) concentrating the evaporator blowdown in the crystallizer by heating the evaporator blowdown;

(ii) wherein concentrating the evaporator blowdown forms an organic melt and causes dissolved solids in the evaporator blowdown to precipitate and crystallize to form solid crystals which are suspended in the organic melt; and

(iii) solidifying the organic melt by cooling the organic melt resulting in a solidified organic melt having solid crystals suspend therein.

13. The method of claim 12 wherein the solidified organic melt is suitable for disposal in a landfill.

14. The method of claim 12 including concentrating the evaporator blowdown to where the concentrated evaporator blowdown includes a solids concentration of approximately 75% to approximately 85% by weight.

15. The method of claim 12 including heating the evaporator blowdown to a temperature of approximately 100° C. to approximately 120° C.

16. The method of claim 12 further including blending fly ash into the organic melt prior to cooling the organic melt.

17. The method of claim 12 further comprising adding calcium chloride to the organic melt prior to cooling the organic melt.

18. The method of claim 12 further including coating the solidified organic melt.

19. The method of claim 12 including removing substantially all free water from the evaporator blowdown in the crystallizer.

20. The method of claim 12 further including:

(a) concentrating the evaporator blowdown to where the concentrated evaporator blowdown includes a solids concentration of approximately 75% approximately 85% by weight; and

(b) concentrating the evaporator blowdown such that substantially all free water from the evaporator blowdown is removed.

21. The method of claim 20 further including heating the evaporator blowdown to a temperature of approximately 100° C. to approximately 120° C.

22. The method of claim 21 further including blending fly ash into the organic melt prior to cooling the organic melt or adding calcium chloride to the organic melt prior to cooling the organic melt.

23. The method of claim 8 wherein the sodium chloride crystals constitute approximately 14% to approximately 16% of the organic solid structure.