US 4,751,887 A · Treatment of oil field wastes

Abstract

A method and apparatus of treating oil field wastes and particularly spent drilling fluids which contain barite and hydrocarbons which includes placing the drilling fluids into the upper end of a downwardly directed rotating kiln. Fuel and pressurized air are inserted into a furnace connected to the upper end of the kiln for supplying a fire to the drilling fluids in the kiln for igniting and burning the hydrocarbons in the drilling fluids as fuel until the drilling fluid is dry. Entrained particulates in the gas stream leaving the kiln are separated in a cyclone separator. The gases leaving the cyclone separator are passed through a secondary combustion unit to assure complete combustion of pyrolized carbonaceous residuals in the gas stream. The gases are then cooled in a heat exchanger and sent to a hydrosonic scrubber which removes the remaining particulates as well as oxides of sulfur. The gases are transported to a vent stack by use of a suction blower which produces the gas flow in the gas handling separation system. The liquids used in the hydrosonic scrubber are processed through a filter system to remove any particulates entrained therein. The solids dropping from the lower end of the kiln are environmentally stable and are then usable as landfill or road bed fill materials.

Claims26

Dependent claims

An apparatus for recovery of barite and clays from spent drilling fluids comprising:

(a) a rotary kiln having a first end higher than a second end whereby drilling fluids therein will flow from the first end to the second end, said kiln having an inlet at the first end for receiving drilling fluids and combustion air;
(b) a burner connected to the first end of the kiln for supplying fire to the kiln for aiding in burning the combustible components of the drilling fluids in the kiln;
(c) a fuel and pressurized air inlet connected to said burner;
(d) an outlet at the second end of the kiln for removing the light weight waste;
(e) means connected to the outlet for removing high weight dried waste from the kiln by gravity;
(f) cyclone separator means located downstream of said kiln outlet for separation of particulates such as barite and clays;
(g) secondary combustion means located downstream from said cyclone separator means for oxidation of residual pyrolized gases from oxidized carbonaceous waste from the kiln;
(h) heat exchanger means for cooling the exhaust gases to substantially a 100% water saturation point with incoming combustion air to preheat the combustion air;
and
(i) means for removing residual oxides of sulfur from the exhaust gases prior to venting to the atmosphere.

7 more elements

An apparatus for treating wastes containing carbonaceous materials, comprising:

(a) a rotary kiln having a first end higher than a second end whereby material rotating therein will flow from the first end to the second end, said kiln having an inlet at the first end and outlet means at the second end;
(b) means for injecting burning fuel and air into said first end of said kiln to cause substantially complete combustion of the carbonaceous materials in the wastes to leave only dry, solid, non-combustible residue gases;
(c) separating means connected to said outlet means for separating heavier solid materials exiting said kiln from lighter materials exiting said kiln, said separating means including suction means for entraining the lighter materials in the residue and gases from said kiln while permitting heavier solid materials to separate from the residue and gases by gravity;
(d) means downstream from said kiln for separating particulates in the gas stream before it is furnished to a secondary combustion unit for substantially complete oxidation;
(e) means downstream of said separating means for combustion of pyrolized gases resulting from oxidation of the carbonaceous materials in said kiln;
(f) means for cooling exhaust gases leaving said means for combustion of pyrolized gases to a water vapor saturation point;
and
(g) means downstream of said means for cooling for scrubbing particulates and oxides of sulfur from the exhaust gases prior to venting to the atmosphere.

5 more elements

Dependencies are inferred from the claim text.

Treatment of oil field wastes

Life of this patent

Treatment of oil field wastes

Life of this patent

Abstract

Claims26