By: Thomas G. Zitrides, President Bioscience, Inc., Bethlehem, PA
The rapid growth of the ‘super service station,’ which offers grocery shopping and fast food as well as gas and oil, has provided a major new market for biotechnology products.
The first major application in the automotive service field was bioremediation, use of hydrocarbon degrading bacteria as a cost-effective means to clean up soil and groundwater contaminated by leaking gas tanks. Many of the new service-station products are outgrowths of this technology.
For example, one new biological product is used directly on surface spills of oil and other hydrocarbon wastes, including gasoline. It is a blend of specialized oil absorbers plus naturally-occurring bacteria selected for their ability to break down a broad range of wastes from petroleum recovery, transport, storage and refining. It also contains nutrients to stimulate bacterial growth.
Just enough product, in powder form, is applied directly to the spill to absorb and contain it. The absorber contains no hazardous materials and presents no environmental hazard when used as directed. Disposal methods for the absorbed material depend upon local, state and federal regulations, but its hydrocarbon content will diminish significantly with time, as the bacteria convert organic molecules to carbon dioxide and protein.
Hard Surface Cleaning
While original biological products were intended for soil and water clean-up, there are now formulations designed to clean hard surfaces, such as concrete, drain pipe interior walls and garage sumps. Such products are ideal for cleaning chronic oil spill areas such as garage floors, sumps or the area around gas pumps.
The biological cleaners consist of liquid biodegradable cleaning compounds mixed with specialized microbes and enzymes. The cleaning compounds dissolve and emulsify hydrocarbon deposits, while the naturally occurring microbes in dormant form become activated and digest the dissolved hydrocarbons.
Drain and Trap Cleaners
Service station drains and traps often become clogged with grease deposits, while at the same time toxic chemical drain and trap cleaners are being banned from many areas. Biological cleaning agents have become the choice for fast-food restaurants faced with grease trap problems plus strict municipal ordinances. The same types of cleaners are now being used in service stations to keep drains free-flowing and eliminate sewer problems downstream.
Biological cleaning agents are a blend of microorganisms that liquefy greases and fats to keep plumbing systems free of blockage. They also contain bacterial enzymes and biodegradable surfactants that enable the grease-degrading microorganisms to gain a foothold on deposits long enough to begin producing their own fat-dissolving enzymes.
One popular type is a dry powder that is mixed with water and added directly to the drain or trap. A similar product in liquid form can be metered into the system where regular maintenance is necessary to keep plumbing systems free-flowing, avoiding blockages, odors and costly physical clean-outs. It can be added to the system manually, but is generally used with a low-cost programmable pump. It is especially useful in today’s service station, which may have a multi-use sewage system serving rest rooms, floor drains and a kitchen area.
Both sewage and surface run-off from service stations can present problems to downstream municipal wastewater treatment plants because of hydrocarbon content (for example, gasoline, antifreeze and brake fluid). Municipal plants can cope with high levels of such compounds in the influent through the use of a blend of selected microorganisms plus activated carbon. The breakdown of complex, mixed hydrocarbons by bacteria proceeds in sequence. Each step requires different enzyme systems, and in many cases, different microbes, to achieve. A blend of microbes selected to perform several progressive steps makes it possible to degrade even such recalcitrant contaminant’s as antifreeze.
The powdered activated carbon in the formulation acts as an adsorbent to concentrate absorbable hydrocarbons and provide a site for the growth of microorganisms. The combination augments indigenous biomass in the wastewater treatment system to enhance removal of difficult-to-degrade organics such as the BTEX (benzene, toluene, ethylbenzene and xylenes) components of gasoline.
In the past, the ability of microbes to degrade wastes was used as an excuse to pollute nature would take care of the problem. With the realization that natural cycles take too long came efforts to accelerate the processes. Without genetic engineering, simply by selecting microbes that have adapted to polluted environments, grouping them in effective teams, and creating favorable conditions for their growth, it is possible to dispose of the organic by-products of the automotive/hydrocarbon age rapidly, safely, and cost effectively.