Waste lubrication oils, antifreeze and solvents at one time were disposed of as a single-source low-level liquid waste or burned in a oil-fired heater (after removing the anti-freeze). In California, and increasingly the rest of the country, this can no longer be done. Everything has to be separated into different levels of waste, which increases the disposal costs significantly. In California, waste oil cannot legally be burned in a stationary heater and it can be burned in mobile applications (trucks, snowcats, etc.) as a fuel mixture only if a long list of requirements is met. Used oil filters have to be stored and shipped out for disposal. To add to the frustration, there is a 16 cent per gallon “refundable” charge added to the lubricating oil purchase price that is redeemable after the waste oil is picked up—provided it is not contaminated by anti-freeze or solvents.
Reducing the waste-stream end-product is the most effective way of dealing with hazardous waste. If the waste stream is reduced, the cost of buying the products that turn into hazardous waste is also reduced.
Oil Sampling
An oil-sampling program is the best way to establish proper oil change intervals for each equipment type. This requires that quite a few oil samples be taken on different machines until you feel confident with the results, at which time you can back off the amount of oil sampling. But this test period will pay for itself very quickly because not as much oil will have to be bought, fewer filters will need to be disposed of and, if the oil changes can be extended, less waste oil will accumulate.
What to watch for in the samples, depending on what sampling service you use, is the amount of suspended solids and soot, the total base number (TBN), sulfur level, oxidation level, wear metals and silicon (dirt). Whatever service you use should be able to interpret the results and answer questions. Oil sampling also will give you a look inside the engine, gear box or hydraulic system to see how much dirt is getting in or if anti-freeze is present in the oil, and how much and what type of wear is taking place.
The type of oil used also makes a difference. Air-cooled engines generally require an oil that will run at high temperatures. Claims that an oil, especially semi- and full-synthetics, will reduce engine soot at higher elevations are not founded in fact. The cost will be higher and the results less than advertised.
Soot Problems
Equipment manufacturers’ oil-change recommendations are based on worst-case conditions. At many ski areas, altitude also plays a part in setting engine oil change intervals. At higher elevations, unburned fuel in diesel engines turns to soot, which is washed into the engine and stays suspended in the oil.
Soot is a sub-micronic scrouging agent and is impossible to filter out without removing the oil additives along with the soot. In a turbocharged diesel engine that runs at a constant load and rpm, the amount of soot will be minimal and oil-change intervals can be greatly increased — up to 700 hours or more depending on conditions. Many turbocharged diesel engines have a ratio valve that will limit the amount of fuel until boost pressure is reached. If this valve needs adjustment, the soot level can be very high.
The difference in engine oil soot levels between a loader and another type of vehicle using the same engine can be great. A loader is on-and-off the throttle all the time and is a high producer of soot. A grooming vehicle or dump truck stays on the high end of the torque curve most of the time and will burn fuel more efficiently. Excessive idling is also a soot producer.
Some experts say that soot is not the problem that it is made out to be and believe that as long as you are getting good engine life, you don’t need to be too concerned about soot levels. The TBN, viscosity and wear metals present are a better marker of oil condition. In California, diesel fuel quality regulations will go into effect in October that should increase the longevity of engine oils and may actually lower the level of soot.
Oil-Change Intervals
Oil change intervals for gas engines can be extended if the following is kept in mind: Newer fuel-injected engines that are run at operating temperatures for more than 30 minutes at a time can be extended to 10,000 miles. Older carbureted/automatic-choke engines and engines that are not run at operating temperature for over 30 minutes at a time, will usually not go over 5,000 miles, or annually, before needing an oil change.
Hydraulic oils are the lifeblood of grooming vehicles. They drive the tracks, run the tiller and control the blade. Most manufacturers recommend changing the hydraulic oil every 600 hours of operation. Hydraulic fluid does not “wear out”; instead, it becomes contaminated with very small wear particles and water and can deteriorate from overheating. In the environment that grooming vehicles work in, the greatest problem is water in the oil. Anything over 5 ppm (parts per million) of water will begin to attack metal surfaces, controllers and valve plates and will cause electro-mechanical valves to stick. Water gets in from hydraulic-oil heat expansion and contraction, contaminated transfer cans, snow in quick disconnects and other ways.
Oil Filtration
In hydrostatic drives, any wear particle 5 micron or larger will cause scouring of plates and sitting of electronic controllers. Sundstrand hydrostatic drives are installed with a 10 micron suction filter. Any finer filtration than this will cause filter restriction problems, premature charge pump and even drive pump failures.
As a pump and motor wears, metal particles smaller than 10 microns accumulate in the oil. To get rid of this accumulation, the oil should be changed. Actually, the oil is diluted with new oil as the hydraulic lines and cylinders still contain old “dirty” oil.
The best way to filter and dewater the hydraulic oil is to use an oil return line filter that has a low micron rating and can remove water down to 5 ppm. The filter has to be placed on the tank return line downstream of the cooler because the cooler would cause too much restriction during cold start-up. The filter head should have a 25 psi bypass rating to keep filter back pressure low during cold starts.
There is available from Zinga Filters a spin-on filter that is rated to under 5 ppm water and 3 micron nominal rating. This filter system is more economical than changing 15 to 18 gallons of hydraulic oil every 600 hours on grooming machines that still leaves much of the old dirty oil in the system. This type of filter works well on all hydraulic systems. Another benefit is that it is on the return line where it can catch debris from a failure in the system and will reduce the contamination to other pumps using a common hydraulic tank.
An external transfer pump filtration system can be made that will take the hydraulic oil out of the vehicle; pump it through a filter and into a holding tank and then return it if a filter is not mounted on each vehicle. This will remove most of the contaminates and can be used for removal and storage of hydraulic oil during repairs. In addition to the 3 micron nominal rating, it would be a good idea to install a 3 micron absolute filter on the transfer system.
A simple test will show if water is present in the oil, when the filter needs to be changed and as a means to establish filter-change intervals. Using a hot plate heated to about 350 degrees F, place a small drop of oil on the hot plate. If it sizzles and boils then it has over 5 ppm of water and the filter needs to be changed. If there is concern that the filter is filling with water or wear particles, a 35 psi gauge can be installed on the inlet side of the filter head. If there is over 25 psi of back pressure at operating temperatures, then the filter needs to be changed.
Dry, clean hydraulic oil can be used indefinitely, especially on grooming vehicles that leak excessive amounts of hydraulic oil. On systems that do not leak excessively, send in an oil sample every 600 hours or so to keep track of the condition of viscosity and additive package.
Using a synthetic gear oil that will not keep water in suspension, will reduce the temperature of most gear boxes by 15 percent and will coat gears and bearings minimizing rusting during non-use months. They also will allow you to extend oil-change intervals. Just inspect the oil and drain water from the bottom of the gear box every so often. In high-heat applications, pay close attention to fluid levels and the condition of the fluid.
Anti-Freeze
Anti-Freeze is another hazardous waste that has to be dealt with. Anti-freeze does not wear out, it just loses its corrosion inhibitor package and absorbs other contaminates from the engine. Occasionally, however, anti-freeze will be burnt and should be disposed of.
A simple way to recycle anti-freeze is to filter it, check the temperature protection level and reintroduce an additive package such as Nalcool. Another way to accomplish this while the anti-freeze is still in the vehicle is to test it and add the additive package as indicated.
The best way to re-use anti-freeze is to distill it using one of the distillation units available on the market. It is expensive, but so is disposing of the old and buying replacement anti-freeze.
Fuel Filters
The number of fuel filters replaced can be reduced by using a larger filter at the fuel island dispenser and extending the vehicle fuel-filter change interval. By using a 20 micron filter, most of the contaminates dumped out of the storage tank with the fuel will be removed.
If the fuel flow starts to diminish, change the filter. Also keep a close watch on the amount of water in the bottom of the storage tank. Pumping the water off the bottom of the tank twice a year is usually enough to take care of problems.
Keeping the fuel dry, clean and free of bacteria will greatly reduce the number of fuel problems and filter changes needed.
Once the number of fluid filters is reduced, they still have to be disposed of properly. The cost for each barrel of filters is about $100, but crushing them allows at least three times as many in the one barrel for the same cost. Commercial crushers are available for around $1,500, or you can make your own, but be sure to have a safety shield on the press, as oil or the filter can fly out, causing injuries. Re-usable filters are making some inroads, but still lack respectability. The quality of filters also makes a difference and a comparison of beta ratios shows which ones are more different.
Oil Disposal
Chlorinated hydrocarbon solvents (mostly TCE) are recognized as a long-term health hazard and can end up in the waste oil quite easily. TCE contaminated waste oil can cost up to $8.50 per gallon to dispose of, compared to 33 cents for regular waste oil. In California, 1,000 ppm is the limit of chlorinated hydrocarbon solvents in waste oil before it is considered a higher-level hazardous waste.
There are alternative hydrocarbon-based and organic-based solvents on the market. They do not air-dry well and, depending on the brand, will leave a coating on cleaned parts. Organic solvents are biodegradable and can be disposed of in waste oil with no problems and, although they are expensive, they will last a long time and seem to do an excellent job. The alternative hydrocarbon solvents are relatively inexpensive and can be disposed of in regular drain oil, but their longevity is not as good.
There are companies that do solvent-tank cleaning, recycling of cleaning solvents, and supplying the solvent tanks, if needed, which is much cheaper than handling these solvents yourself. As with any chemicals, there may be associated long-term health hazards so use proper ventilation and protective clothing.
Waste Storage
Once the hazardous waste stream has been controlled, there is still the problem of how to store it until it can be disposed of. For waste oil, the best way is to store the oil in a large storage tank. If it must be tested before pickup, you can test the whole load with one test kit.
For higher-level waste, the best way to store it is in 55-gallon drums in a small ventilated overseas-type transit container set in a concrete containment dam. Mark each drum with the known contents and date it. The drums stay dry and do not get damaged by grooming vehicles or snow-removal equipment. One important thing to remember is that you are responsible for the waste until it reaches its destination. Use a reputable company that has proper permits and is bonded.
These are some of the ways and costs of reducing and monitoring the hazardous waste stream. They are not limited to grooming vehicles, but can apply to chairlift auxiliary drives and other reuqipment, both stationary and mobile. There are many other methods to reduce waste, such as filter restriction indicators for air filters, air filter pre-cleaners for dusty conditions and selection of the proper fluids and additives for diesel fuel, to name a few. Because most ski areas are located on environmentally-sensitive sites, we have a very high level of responsibility to reduce and properly dispose of the waste we generate.
