How to get quality water at your wash
The reclaim technology developed in recent years gives carwash owners capability to build their location in areas they never would've been able to build before.Washes are no longer limited
Regulations, water restrictions, sewer hook-up fees and tap fees made many areas unsuitable for a wash.
There are many variables incorporated in these restrictions, including, but not limited to:
- Discharge permits;
- Water usage;
- Oil and grease; and
- Total Dissolved Solids (TDS) values in discharged water.
The discharge pipe from the carwash trench is no longer the end of the carwash owner's responsibility. It is the beginning of his or her wash-water management system.
Recycling technology is in a stage where new markets are being created. Although many carwash entrepreneurs are enthusiastic about applying the current technologies, the technical issues involved need to be realized.
For recycling systems to perform as expected, they require the successful combination of recycling equipment, chemical suppliers, and carwash operators.
To understand the technical issues involved with different types of recycling technology you must review some of the most popular forms of carwash water reclaim.Filtration technology
This technology uses absolute, or depth, filters such as:
- Sand filters
- Screen filters
- Bag filters
Normally, some type of inline filtration will capture all particles in the wash-water above the particle size the filter allows.
For example, a 20-micron filter media will trap all media larger than 20-micron. Particles that are smaller than 20-micron, such as chemicals or road salt, will pass through the filter and remain in the water.
When the filter is full, a backwash or manual replacement of the filter is required. With current technology, the backwash can be an automated process.
The particles that are allowed to pass through the filter cause a continuous buildup of dissolved chemicals and road salts, also known as TDS.
This makes it necessary to add fresh water to dilute the increasing Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) levels and to fight the inevitable odor problem associated with these values.Ozone technology
Ozone is used to fight odor created due to the fact that COD and BOD create ideal living quarters for bacteria, the culprits behind the odor.
The injection of ozone gas will oxidize the bacteria, helping to eliminate the odor problem for a short period of time. For this reason, ozone is an accepted method for fighting the odor problem faced by carwash owners.
It still cannot reduce COD or BOD levels, nor can it reduce salt values. Wash owners must remember, however, that ozone is one of the most toxic gases in the world.
Using ozone to control odor is working against the natural process. If the dilution with fresh water is too low and the dissolved chemical levels are continuing to rise, the bacteria will prevail and may change the chemistry of the system.
Ozone, once it oxidizes organic compounds, such as chemicals, becomes oxygen (O2). This O2 can be used by the bacteria to accelerate their growth.
For technology involving filters and ozone to properly work, the operator must balance his fresh water intake to control his chemical balance in the recycled water.Bio-technology
Bio-technology is one of the latest technologies introduced into the reclaim industry.
Previously, due to the size of bio-reactors and the sensitivity of the systems, bio-technology would not have been successful in the carwash industry.
But developments in bio-reactor types and a growing knowledge of nutrients and vitamins made it possible for the technology, commonly used in industrial wastewater plants, to be used in carwashes.
Bio-technology was first applied at locations where environmental issues made it impossible for owners to build washes.
With the knowledge gained from these first applications, up-flow reactors were created. These systems could create reusable, odor-free water.
Although bio-reactors are the largest type of reclaim systems, in some wash owners' opinions they can outperform filtration systems.
The bacteria that cause odor in filtration technology are now encouraged, with oxygen, vitamins, and nutrients, to be active and reduce (eat) the COD and BOD.
This causes the facultative bacteria to become active, keeping them from producing odor. This means the need for fresh water intake to fight odor is no longer an issue and larger amounts of water can be recycled.Environmental scrutiny
Until recently, recycling wasn't a concern for many owners. The growing concerns from environmental agencies and local governments have caused today's carwash owners to be placed under scrutiny, persuading many owners to invest in reclaim systems.
Owners and operators alike realize that maintenance is a major issue in a carwash. Many of these technologies require a large amount of maintenance and constant replenishment of chemicals.
But these new methods of reclaim make it easier for wash owners to create wash sites that offer an improved quality of water through environmentally friendly means.
Jan Verwater is the senior vice president of research and development at VERwater Environmental, LLC.