Oil/Water Separation

The process of drilling, completing and producing an oil well is incredibly water intensive. As a result of drilling activities, “produced water” – a term used in the oil industry to describe water that is produced as a byproduct along with the oil and gas – becomes contaminated with dissolved solids, minerals, organic materials, and naturally occurring radioactive materials (NORM).

Water from fracking, or “frac water,” is contaminated with noxious chemicals and gas and, along with the produced water, gets injected under pressure into disposal wells. These disposal wells can contaminate the underground aquifers and are now known to be the cause of earthquakes. Oil disposal wells have now been shut down in Oklahoma, Kansas, Arkansas, and Pennsylvania, resulting in the shutdown of oil projects because they have nowhere to put their produced, or frac, water.

Reliable One has a patent pending on its oil/water separation unit, called the SFC 6000. It is so-named because it can be built to process 6,000 gallons-per-minute, separating water and oil in produced and frac water. The SFC sits at the front end of the processing stream. This piece of equipment is extremely important because it is what gives Reliable One its price advantage in this industry.

Note: Image may not represent exact patent-pending design of final unit

As the water enters the SFC 6000, its oleophobic and hydrophilic membrane coating attracts water and repels oil off to a separate container while removing the Total Suspended Solids (TSS). Any residual oil, especially the emulsified oils, is taken out via the electrocoagulation unit (ECU). The ECU applies an electrical charge to the water and changes the particle surface charge, allowing suspended matter to form an agglomeration. It effectively removes suspended solids to sub-micron levels, breaks emulsions, such as oil and grease or latex, and oxidizes and eradicates heavy metals from the water as well as toluene, benzene, sulfur, arsenic, radium, and bromide without the use of filters or the addition of separation chemicals.

Along the process stream, the ECU also sequesters and “drops down” the valuable minerals including gold, silver, platinum, palladium, and lithium into their respective vats for sale to the smelter. After processing 30,000 gallons (daily capacity) of produced water, the demonstration-sized plant is left with between 1.5% – 2% of marketable oil. That is 450-600 barrels of oil that belong to the plant.

Reliable One’s process separates out the toxins and cleans the water to a level that it can be sold 1) to oil and gas or mining operations for re-use; 2) to beneficial status for agricultural use; or even 3) to safe drinking standards (each level requires additional filtration processes and equipment). Some of the technologies the Company may use depend on the area and contamination levels and might include, but are not limited to, seven micro level screens, advanced Ultra filters, multiple ionic separators, UV wave bombardment, electrocoagulation unit, and platinum plate electrolysis for molecular separation.

Since produced water and frac water contain large amounts of suspended solids, including hydrocarbons, Reliable One’s treatment process contains six different steps.

Step 1) Ion Exchange process – ion exchange involves removing the hardness ions calcium and magnesium and replacing them with non-hardness ions, typically sodium supplied by dissolved sodium chloride salt, or brine. The softener contains a microporous exchange resin, usually sulfonated polystyrene beads that are supersaturated with sodium to cover the bead surfaces. As water passes through this resin bed, calcium and magnesium ions attach to the resin beads and the loosely held sodium is released from the resin into the water. After softening a large quantity of hard water the beads become saturated with calcium and magnesium ions. When this occurs, the exchange resin must be regenerated, or recharged. To regenerate, the ion exchange resin is flushed with a salt brine solution. The sodium ions in the salt brine solution are exchanged with the calcium and magnesium ions on the resin and excess calcium and magnesium is flushed out with wastewater. Frequency of the regeneration or recharge cycle depends on the hardness of the water, the amount of water used, size of the softener, and capacity of the resins. Sixty to 120 minutes generally are required for the brine to pass through the unit and flush the tank before soft water is available again.

Step 2) Electrocoagulation – is performed by applying an electric current across metal plates that are submerged in water. Heavy metals, organics, and inorganics are primarily held in water by electrical charges. By applying another electrical charge to the contaminated water, the charges that hold the particles together are destabilized and separate from the clean water. The particles then coagulate to form a mass, which can be easily removed.

Step 3) Flocculation – after the raw water has been coagulated, it is gently mixed by large mechanical paddles in a process called flocculation. Flocculation causes the fine, light particles that were created during the coagulation process to mature into larger, denser, stable particles that will settle quickly.

Step 4) Sedimentation – the flocculated water then travels into primary settling basins or clarifiers. In the primary settling basins, the large, dense particles formed during the coagulation and flocculation processes settle allowing the clarified water to be separated and forwarded on through the remainder of the water treatment process. The settled particles form a sludge layer on the bottom of each primary settling basin. This sludge is periodically removed from the basins.

Step 5) pH Adjustment – the next step in the process is adjustment of the pH of the water. Lime, also known as calcium oxide, is added during this step to achieve the desired target pH. Adjusting the pH makes the water more basic, and less corrosive to the pipes it will eventually travel through. A small amount of polyphosphate solution is also added with the lime. Polyphosphate is used as a sequestrant, which helps to keep the lime in dissolved  water.

Step 6) Filtration – the final step in the purification process is filtration.   Rapid gravity filters use granular filter media (sand and anthracite) to remove any remaining suspended particles in the water. This step in the treatment process consists of passing the water through a filter at a controlled rate. Any particles remaining in the water adhere to the filter media and are removed from the water. Micro filtration and Ultra filtration are then used for further physical separation. The extent to which dissolved solids, turbidity and microorganisms are removed is determined by the size of the pores in the membranes. Substances that are larger than the pores in the membranes are fully removed. Substances that are smaller than the pores of the membranes are partially removed, depending on the construction of a refuse layer on the membrane. Micro filtration and ultra filtration are pressure-dependent processes, which remove dissolved solids and other substances from water to a lesser extend than nano filtration and Reverse Osmosis. Membranes with a pore size of 0.1 – 10 µm perform micro filtration. Microfiltration membranes remove all bacteria. Only part of the viral contamination is caught up in the process, even though viruses are smaller than the pores of a micro filtration membrane. This is because viruses can attach themselves to bacterial biofilm. For complete removal of viruses, we must then employ ultra filtration. The pores of our ultra filtration membranes can remove particles of 0.001 – 0.1 µm from fluids.

After filtration, the purification process is complete.