Environmental Science & Engineering - www.esemag.com - January 2003
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Lubricants save money in water treatment plants

By Chris Barnes, P.Eng., MBA,
Lubrication Engineers of Canada

Table 1 - Typical results (in Canadian dollars) achieved by several water plants for various types of vertical water pumps.

There is an increasing emphasis placed on ensuring the quality of drinking water, while at the same time there is strong pressure to minimize expenditures. Taxpayers are demanding that their government do more with less money, and, with budget cuts, this has become a reality. This is forcing many plants to analyze their processes in the search for improvements. Finding efficiencies and ways to work smarter has never been more important.

One often overlooked area that can yield a very significant and rapid return on investment is the lubrication of the equipment that pumps water. A small investment in improved lubrication can yield an incredible rate of return through savings in capital costs, repairs, maintenance, downtime and electricity. It costs four or five times as much to apply the lubricant as it does to buy the lubricant, so choosing and buying the right one is a crucial step. A carefully selected lubricant can pay for itself many times over, for the cost of the lubricant is miniscule compared to the value of the equipment that it is protecting.

The most logical place to start is with the equipment that uses the most electricity. The money that is saved on electricity, by reducing friction, typically pays for the cost of the superior lubricant many times over. This payback period is often as short as two months.

Lubrication Engineers developed its ZAP Energy Saving Program to help clients identify applications where significant energy savings can be achieved and to project the dollar value of these savings. This is a free service.

In water treatment plants, the starting point is usually the water pumps which are responsible for delivering water to the treatment facility from local rivers, lakes or reservoirs, and supplying the water to the water customers. Achieving optimum lubrication of these vertical water pumps is important as they normally operate on an almost continuous basis.

Table 1 presents typical results achieved by several water plants across North America for various types of vertical water pumps. The savings are significant, as they are almost always many times greater than the cost of the lubricant itself, resulting in a healthy return on investment. In addition to producing energy savings, the lower friction also results in lower wear and tear on the equipment, which produces additional savings in repairs and capital expenditures. This “found” money helps to ease the pain of budget cuts by freeing up some extra cash for other projects.

Other areas tend to be less electricity intensive, but nevertheless are still ripe for improvement and yield fruitful savings. One of these applications is the meter pump, which dispenses water treatment chemicals such as hydrofluorosilic acid. Mechanics have noted that when they change the gear oil in these pumps, it is often oxidized (dirtier and thicker than it should be) and contains a high concentration of wear metals. When they switched to an advanced technology low-friction paraffinic gear oil in this application, they noticed a significant difference. No wear metals were visible, only very low levels of wear metals were detected by oil analysis, and they were able to continue using the same oil for over four years compared to just one year on the commercial grade 85W-90 gear oil.

A simple lube audit can identify other candidates for improved lubrication and ZAP Energy Savings. A little bit of better lubrication can go a long way towards a more efficient operation.

Part I - Lubricants in Wastewater Treatment Plants - appeared in Environmental Science & Engineering, September 2002.

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