Advancements in spot-free
October 11, 2010
In bay automatic vehicle washing has come a long way from the days when a free wash came with the purchase of eight gallons of gas. Not just found behind the service station anymore, one of the faster growing segments in vehicle washing is the stand alone in-bay automatic in a strip mall, self storage lot, or added to a self-serve wash. With the exception of the former, these washes are often being built by people without a lot of experience in vehicle washing, for them it is an investment opportunity.
Equipment, price and ownership, are the three sides of this story. All three have grown exponentially.
First, equipment has matured from a “garden hose” attached to three brushes running dish soap, if any soap at all, that just beat at the dirt on the vehicle. Today, sophisticated computer-controlled wash units size to the vehicle for optimum cleaning, using spot-free water, high grade chemistry and often heat to clean the customers’ vehicles to a level that was unheard of just a decade or two ago.
Instead of one wash, there are at least three options to as high as seven or eight packages in some places. Obviously, this huge leap forward in capabilities of the equipment has come with a large increase in the cost of the equipment.
Fortunately, the second part of the story — price — has also risen from free to $3, 4, 5, and in some areas $8, 9, 10. Consumers will pay these amounts if they feel they are getting a good value. This will help offset the cost and make the wash a good investment.
The third and final part of this is the wash owner/operator. Being in the equipment business, we speak to a large number of people looking to buy or build a wash. The number of doctors, lawyers, accountants, real estate brokers, and executives asking for this help has grown. They ask tough questions concerning equipment reliability, service capability, and product liability. They are not the hands-on mechanics of the previous generations of wash owners — most of them use the carwash as a way to invest money.
These often highly educated investors are also often trained to approach challenges analytically. They will rely on equipment vendors and distributors for advice and expertise to guarantee their investment; they will listen to their customers on what it takes to achieve a high level of customer satisfaction.
What has this got to do with spot-free rinse for in bay automatic vehicle washes? I point this out to show the business is changing. Just as the level of sophistication in the equipment and the companies who sell and service this equipment has grown, so has the wash owner.
It is important for everyone to realize that we are not backyard builders selling just to hands-on mechanics anymore. The new owners are expecting well-built equipment, good factory and distributor support, well-written manuals, third-party testing laboratories seals of approval (i.e. UL / ETL) — all at great value.
Advancements in spot-free
Spot-free rinse systems for in bay automatics are rapidly approaching standard equipment. A final spot-free rinse effectively displaces all residual chemical and mineral laden water, including reclaim water. This allows the entire vehicle, including glass, chrome and painted surfaces, to dry completely spot-free.
Most carwash manufacturers have made provisions for spot-free rinse to be incorporated into their wash process and either offer or recommend this when building or updating a wash facility. A reverse osmosis system is a simple addition to any wash location and will increase customer satisfaction and create customer loyalty.
Today, many carwash manufacturers include a reverse osmosis system as standard equipment in their carwash packages. Offering spot-free rinsing has become an integral part of the wash process.
Regardless of the brand of carwash you select, there is a spot-free system for you. It is recommended to consult with your equipment distributor when selecting the proper spot-free system for your application. If you don’t have a distributor, your wash manufacturer will be able to assist you in the selection of the appropriate spot-free system.
On the technical side, all RO systems work in much the same way. Tap water is introduced into a pump, which increases the pressure to 180-250 psig and forces water through the membrane. It is recommended to pre-treat tap water before it goes into the RO system. Some water conditions will require additional pre-treatment, so consult the equipment supplier.
Because most municipal water systems use chlorine as an anti-bacteria treatment and membranes do not tolerate chlorine, it is necessary to remove the chlorine before the RO. A simple, activated charcoal filter tank works for this purpose and most RO manufacturers include this as part of the system.
All systems will have some form of a pre-filter, usually a 5-micron pre-filter that is provided to separate the larger solid material from the water. Plugging or damage to the RO membrane or pump will result if the large solid particles are not removed by the disposable filter first. A pre-filter needs to be changed at least once per month; some water conditions may require more frequent changes. When pre-filters are not changed regularly, RO systems will produce poor product water quality and/or a significantly lower production rate.
The most common size membrane used in carwash applications is 4x40-inch, which requires five gallons across the surface of the membrane for every gallon of product or permeate water produced. In years past, most operators would just send the four gallons of “bad” or concentrate water down the drain. Today, water costs are expensive and some locations are limited to how much water they can send to the sewer.
Most, but not all, RO manufacturers recirculate a portion of the concentrate water back into the inlet stream. Out of the five gallons you start with, one gallon of product water goes into the RO storage tank, one gallon of concentrate water goes to the drain, and three gallons are re-circulated.
RO systems are typically sold by the amount of water they produce in a 24-hour period. This is usually at an optimum performance with 77-degree Fahrenheit feed water. Your wash manufacturer will be able to tell you how much spot-free water you will need per wash and with some educated guessing you should be able to determine the size unit you will require.
If your calculations are on the close side, upsize your storage tank or select the next unit size up.
Other uses for spot-free water
The uses for spot-free water in a carwash now also include windows. Do you have a window in your in-bay automatic that you want people from the street to be able to view your wash? Or maybe you have a carwash that is housed entirely in a structure primarily made of glass?
The flying soap, the grime you blasted off that muddy truck, and the junk in the wash bay all accumulate on your windows. Periodically if you rinse those windows with spot-free water you will improve the appearance of the windows and reduce or eliminate the laborious scrubbing that would be required to keep them clean.
A great use of the spot-free water, a wonderful housekeeping tool and another way to reduce labor.
Uses for “reject” water
Sometimes if the site has a reclaim system, the concentrate or reject water is plumbed into the reclaim holding tanks. For every vehicle washed in a system with reclaim you will need six gallons of make-up water due to carryout and evaporation.
With almost all of our applications, this water would come from the final rinse. With the introduction of the reject water into your reclaim you will be turning the water in your tanks over and sending the overflow to the sewer. This will improve the quality of your reclaim water by diluting the solids and therefore keeping it fresher.
In applications without a sewer hook-up, zero discharge may be advised. The concentrate is captured in a tank, as the wash requires “make-up” water to float in the reclaim tank. This water tells the pump the reclaim is low on water and the pump responds by filling the reclaim tank and keeping the wash running, without wasting water.
There are many possible uses for this reject water. In some cases, where there isn’t salt present in the reject water, it can be plumbed into the irrigation system and utilized for the landscaping. Wash systems without a reclaim can still capture the reject and when mixed with tap water can be used in the wash process; this is a good application where the site may not have enough tap pressure or volume of water.
Charles Borchard is the vice president of operations for New Wave Industries, the manufacturer of Pur-Clean Spot-free Rinse Systems and Pur-Water Water Recovery Systems. Borchard is in his 18th year in the water treatment business.