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Custom Applicaiton Controller: Landfills and Extreme Heat

Not all of our customers are able to use an off-the-shelf solution. Three years ago, a landfill company came to us at Waterline Controls. They needed help in developing a control system that would be effective in the hostile environment of a landfill, and we were able to meet the challenge with the design of a custom control system.
Groundwater Pollution Issues Faced by Landfills
One of the major challenges faced by landfills is protecting the groundwater from pollution. The primary way that groundwater is polluted by landfills is through leachate, the liquid that drains from the landfill. Landfills have a plastic liner that protects the soil and groundwater from leachate. However, something has to be done with the leachate that percolates through the garbage.

Leachate Collection System

A leachate collection system is one of the main ways of dealing with leachate. Perforated pipes collect the leachate that collects in the landfill. These perforated pipes then drain into a leachate pipe that transfers the leachate to a collection pond. Some landfills ship the contents of the leachate pond off to be processed, while others process it themselves.
Typically, landfills use pumps with float switches to pump transfer the leachate to the collection pond. Depending on the size of the landfill, there may be hundreds of pumps deployed. These pumps are often solar powered and monitored remotely. Because of conditions in the landfill, the float switches typically used require removal and cleaning every few days. That makes the system difficult to maintain and expensive.

Sensor Issues Caused by Leachate

The leachate that percolates through the solid garbage is usually acidic. And the gases involved as the waste decomposes result in chemical reactions and high temperatures. These kinds of operating conditions are extremely hard on sensors, which is the main reason they have to be removed and cleaned so often. The liquids involved also tend to foam, which can seriously affect the accuracy of some types of sensors. The sensors used to control the pumps perform hundreds of thousands of cycles in just a few months, so accuracy and reliability are vital.

Waterline Controls Custom Solution

At Waterline Controls, we were able to develop a customized solution to meet this landfill’s leachate pumping needs. Our first area of focus was on the sensors. Our sensor probes are made of chemically-resistant stainless steel. That means the acidic content of the leachate won’t impair their performance. Also, the sensor design that we use is not sensitive to the effects of high temperatures. Our sensors work regardless of water quality. They will not plate, foul, or degrade, which eliminates the need for sensor maintenance and the expense associated with it. Foaming does not affect the accuracy, either. The Waterline Controls line of sensors are accurate to within ⅛”, have a 15-year life cycle, and operate at 99% reliability. This alone resulted in a significant improvement over their current solution. Once the sensors had been configured, we were able to customize one of our existing control systems to meet their needs. Our controllers have a modular design so that if a component should fail the entire unit does not need to be replaced. They are easy to install and integrate with existing systems and components.

Contact Us Today!

Whether you are looking for an off-the-shelf water level sensor or a complex water level control system, Waterline Controls is here to help you. We have over 20 years experience in the control systems industry and have designed custom solutions for many different applications. Contact us today!