Problem:
Automatic carwash operators have been challenged by city government officials to reduce the hydrogen sulfide in the effluent being released into the city sewer system from the carwash water recovery tanks. The operators also have a need for a product that could purify the recovered water to a point that the water could be recycled in the system.

Solution:
Histosol OP-Bio was applied directly into the recovery tank at an automatic carwash at a rate of 2.5 gallons per 5000 gallons. Within 48 hours, the hydrogen sulfide odors had dissipated. A maintenance program was started which entailed adding one ounce of Histosol OP-Bio daily to the recovery tank. At the end of the fourth day of treatment, the water in the recovery tank was clear enough to begin recycling the water in the system. The recycled water is used in the wash cycle. The cars are coming out of the wash cleaner than before, with no evidence of water spotting which was a major problem when fresh water was being used. The carwash operator is now recycling the water from the recovery tank on a daily basis. The daily fresh water consumption has been reduced by 70 to 80%.

Conclusion:
The Histosol OP-Bio product's performance exceeded original expectations. Hydrogen sulfide levels were greatly reduced. The water was sufficiently purified to a point that the recycling process has reduced the need for fresh water by over 70%.