How It Works, Controlled Release Technology (CRT)

Functionality

Oxygen is often the limiting factor for aerobic microbes capable of biologically degrading contaminants such as petroleum hydrocarbons. Without adequate oxygen, contaminant degradation will either cease or may proceed by much slower and inefficient anaerobic (oxygen-free) processes. ORC is designed to release oxygen into the subsurface for periods of up to one year depending on site conditions. In the presence of this long-lasting and controlled release oxygen source, aerobic microbes flourish accelerating natural attenuation of gasoline and fuel additives (BTEX and MTBE), diesel, kerosene, jet fuel, gas condensates, fuel oils, lubricants, bunker oil, PAHs, certain metals (arsenic), certain pesticides/herbicides and certain industrial solvents (alcohols and ketones).

When hydrated, ORC is designed to release its full amount of oxygen (10% by weight) over a 12 month period. Upon injection into the subsurface, ORC utilizes its patented Controlled Release Technology (CRT™) to deliver oxygen consistently over an extended period of time, avoiding excessive foaming and oxygen loss seen with commodity chemicals. This enables aerobic microbes to significantly accelerate rates of natural attenuation over long periods of time. ORC saves time and money by increasing degradation rates and improving remediation performance by providing more oxygen on a single injection.

In Situ Application

Remediation with ORC Advanced is typically more cost-effective than ex-situ treatments. With the use of ORC Advanced there is minimal site disturbance with no above-ground piping or mechanical equipment, no operations and maintenance costs and no hazardous materials handling or disposal.

Controlled Release Technology (CRT™) is Critical

Early on, Regenesis researchers noted that in order to optimally stimulate the natural attenuation of aerobically degradable contaminants, biologically usable oxygen was best supplied in low but constant concentrations. Big bursts of oxygen are wasteful and simply “bubble off”, often generating undesirable foaming and producing unwanted preferential flow paths in the subsurface. Regenesis sought to solve this problem by controlling the rate of oxygen release from solid oxygen sources.

The answer was provided by the development of Controlled Release Technology (CRT™). The CRT process involves intercalating (embedding) phosphates into the crystal structure of solid peroxygen molecules. This patented feature, now also available in the ORC Advanced™ formulation, slows the reaction that yields oxygen within the crystal, minimizing “bubble off” which can waste the majority of oxygen available in common solid peroxygen chemicals.

More on ORC and CRT

ORC is intercalated with food-grade phosphate giving it the critical time-release properties that are important in a passive, low-cost oxygen release compound. The term “intercalation” is used here to describe the permeation of phosphates into the crystalline structure of magnesium peroxide. This feature slows the reaction that yields oxygen thus facilitating an extended controlled release. Phosphate intercalation also prevents a process known as “oxygen lock-up.” When water reacts with an un-intercalated magnesium peroxide, a cement-like coating of magnesium hydroxide forms and prevents water from penetrating deeper into the crystal to release all of the available oxygen. ORC’s phosphate intercalation keeps the crystal “open,” preventing this problem and furthering the critical release of oxygen.