Organoclay as a Polishing Media: When It Is Best Used

Standard filters trap particles physically (like a sieve), but Organoclay works through a chemical process called adsorption.

• Modified Surface: Organoclay is made by modifying bentonite clay with quaternary amines. This changes the clay from being water-loving (hydrophilic) to being oil-loving (lipophilic).
• The "Magnet" Effect: The quaternary amines act like a molecular magnet. They have a hydrophilic "tail" that anchors to the clay and a lipophilic "head" that extends outward to attract and lock onto hydrocarbon molecules.
• Non-Swelling Property: Unlike raw bentonite, Ecologix's proprietary MCM-830P is non-swelling. This is critical for a polishing step because it prevents the filter bed from "blinding" (clogging) when it contacts water, maintaining a consistent flow rate.

A standard gravity or plate-pack separator can typically reduce oil concentrations to 15-50 ppm (parts per million). However, environmental discharge limits are often much stricter (e.g., 5 ppm or "non-detect").

• Targeting Emulsions: Standard separators struggle with mechanically emulsified oils—tiny droplets (less than 20 microns) created by the shearing force of pumps. Organoclay is specifically engineered to "pull" these droplets out of the water.
• Removing the Sheen: Even at low concentrations, oil can create a rainbow-colored sheen on the water's surface. Organoclay is the "gold standard" for removing this visible sheen.
• High Capacity: Organoclay can absorb 50% to 70% of its own weight in hydrocarbons. This high capacity makes it a cost-effective "final guard" for the system.

While Granular Activated Carbon (GAC) is a common water filter, it is often a poor choice for oil removal when used alone.

• Efficiency: Organoclay removes oil at 700% the rate of activated carbon.
• The "Blinding" Problem: If oil hits activated carbon, it coats the tiny pores of the carbon (blinding it) and makes it useless for removing other dissolved chemicals like benzene or toluene.
• The "Treatment Train: In a professional setup, Organoclay is placed upstream of activated carbon. It acts as a sacrificial layer that removes the oil and grease, allowing the expensive activated carbon to focus on dissolved organics, which extends the carbon's life by up to 500%.

To implement this polishing step for low flow applications, Ecologix typically utilizes the AHP-55 Liquid Phase Vessel.

• Media Charge: These heavy-gauge steel vessels are charged with 200-250 lbs of MCM-830P media.
• Flow Configuration: The water flows from the OWS into the AHP-55. Because the media is granular, it provides a high surface area for the water to pass through, ensuring maximum contact time between the hydrocarbons and the clay.
• Versatility: This polishing step is effective for a wide range of pollutants, including gasoline, diesel fuel, chlorinated hydrocarbons (PCBs), and even some trace heavy metals.