BIOREMEDIATION CONTAINMENT SYSTEM (BCS) TECHNOLOGY

BCS Design & Engineering

One of the critical environmental factors effecting bioremediation is temperature. Temperature has an important effect on microbial activity and has been correlated with biodegradation rates of specific organic compounds. Research has documented that the optimum temperature range for degradation is 5 o C (40 o F) to 45 o C (113 o F). If temperatures drop below this range microbial activity can slow or cease as microorganisms become dormant. In colder climates effective treatment periods are shortened which can correlate to longer cleanup times.

The Bioremediation & Containment System (BCS) designed by DRD Environmental Services Inc. is a self-contained mobile treatment unit that can be setup on limited-space, remote or non-disturbance sites and operated with scheduled operation and maintenance procedures. The technology was engineered so waste reduction can occur under controlled environmental conditions favorable for aerobic bioremediation. The BCS unit was originally designed for enhanced bioremediation under cold climate conditions. Heated BCS units can maintain a 26 o C (80 o F) treatment temperature at extreme ambient temperatures of up to - 51 o C (- 60 o F) and wind speeds of 160 kmph (100 mph).

The BCS unit batch treats approximately 90 yd 3 of contaminated waste at one time. The unit's overall dimensions are: 57 ft length; 9.5 ft width; 12 ft height. The BCS is built with insulated heat transfer coils enclosed in the walls and bottom to control treatment temperature levels and aeration ports for air sparging. Injection ports for waste mixing and chemical application are spaced along the inside container walls for even distribution. Typically, the chemical agent is applied from a connected external source. Automated mixers traverse the length of the container creating vertical circulation patterns to achieve and maintain a homogeneous mix. The treatment unit is powered by a detached 30 ft x 8 ft motor shed which houses the generator, hydraulic and heating units, compressor and 500 gal (1892 L) fuel tank.

BCS technology offers a real time solution for the treatment of oil-based cuttings during drilling operations so remobilization for post-operation waste cleanup is unnecessary. It has been proven effective in treating tank bottoms and upstream oilfield sludge. This technology allows cleanup to proceed year around and essentially eliminates land application treatment issues such as contaminant leaching and off-location surface runoff. Post-treated materials can usually be spread directly on the site significantly reducing handling and disposal costs.

Treatment Process

Native soil containing indigenous microorganisms is introduced to the contaminated material inside the BCS unit during initial loading. The untreated mix is sprayed topically with N.A.L.E.-IT TM (Microsolv) at a ratio of one (1) part chemical agent to twenty (20) parts water while operating the mixers. This procedure results in an even distribution of chemical agent throughout a homogeneous mix. If necessary, additional water is applied to bring the mix's moisture content level up to 30-40%. Critical operating parameters are monitored during routine maintenance service calls so adjustments in temperature, moisture content, pH and dissolved oxygen can be made, if necessary. Sampling of the waste is conducted on a predetermined schedule to document petroleum hydrocarbon degradation rates, microbial populations, and mix characteristics.