High-Pressure Slurry Ablation: Applied to Hydrocarbon Remediation

The global market for onshore post-oil spill management was worth approximately $90 billion in 2015. Incidents such as well blowouts and pipeline failures in North America were major drivers for this sizeable market cost. In respect to strictly upstream oil and gas activities, a recent study found that, on average, there are 55 reported oilfield spills per year for every 1,000 wells. In addition to these spills, acute events such as the Kalamazoo pipeline spill in 2010, which spilled approximately 800,000 gallons of crude oil, may cause catastrophic oil incidents that require hundreds of millions of dollars for cleanup. In the United States, the remediation of contaminated sites is of paramount importance to policymakers, regulators, and the public. Current remediation methods for hydrocarbon contaminated material include soil washing, bioremediation, landfarming, electro-kinetic sand remediation, thermal desorption, or simply hauling oil spill material to a landfill. These current methods are complicated, costly ($50-1,000 per ton of material impacted) and take a long time (e.g., soil washing takes, on average, 23 months for cleanup).

Disa can use high-pressure slurry ablation (HPSA) technology to remediate hydrocarbon contaminated sands and soils in a manner that meets stringent environmental regulations, is mobile deployed, provides high and continuous throughput, maintains a small footprint, significantly reduces waste, and is much more cost effective than conventional technologies.

In HPSA, hydrocarbon separation from the associated clay/sand-organic matter is achieved by intensive particle to particle collisions provided by high-pressure pumps moving slurry through a set of opposing nozzles causing liberation of both organic pollutants existing in the liquid phase and soil organic matter with tightly absorbed hydrocarbon fractions. The contaminated liberated fractions can then be recovered using conventional physical separation methods. Due to its unique application of energy, HPSA has the potential to provide more efficient pollutants removal and shorter processing times to meet environmental cleanup standards for oil spills. Disa’s HPSA product is compact while providing high throughput, so it can be part of a modular, skid-mounted hydrocarbon contaminated soil remediation system operated on-site using only warm water and environmentally friendly reagents. This modular approach enables pollutant removal and creates clean solids that can be safely disposed on-site. Our innovation can result in a significant reduction in oil spill material transport to landfarms and disposal facilities, bringing significant economic and environmental benefits to the post-oil spill management market.

Over the years, a range of in-situ and ex-situ technologies have been used to reduce and remove oil contaminants from soil. Experience has shown that most of these treatment processes can be costly in capital, operations, and maintenance. The complexity and prohibitive costs of these treatment methods can be attributed to pollutant characteristics, heterogeneities in soil properties, long processing times, process inefficiencies (energy, chemical, and water consumption), and site-specific limitations.

At the core of our technology is the HPSA process for hydrocarbon removal that is achieved by intensive particle to particle collisions. The particle collisions are enabled by multiple high-pressure pumps moving high-density pre-conditioned slurry through a set of nozzles creating the impinging jet region with the sufficient levels of shear and stresses to achieve agglomerate attrition and hydrocarbon disassociation from the associated clay/silt/sand-organic matrix. The pre-conditioning stage of the process involves the contaminated soil mixing with moderately heated water and an environmentally benign solvent, where the HPSA liberated products are separated using conventional physical separation techniques, including froth flotation, sedimentation, dewatering, and carbon adsorption.

Compared to existing solutions for soil washing, which rely on energy-intensive mechanical agitation in stirred tanks, HPSA, with its unique application of energy, has the ability to provide more favorable hydrodynamic and thermodynamic conditions for hydrocarbon liberation, better slurry conditioning and aeration, better reagent mixing, shorter processing times, and improved hydrocarbon recovery to meet environmental cleanup standards for oil spills.