Service facilities and rest stops serve to ensure comfort and safety on long highway journeys. However, for the operator ASFiNAG, the intensive use of the facilities increasingly led to maintenance challenges. Thanks to Sulzer’s Muffin Monster™ shredder and Piranha pump technology, however, clogged wastewater pumps are now a thing of the past.
The company operates 87 fully equipped rest areas with gas station, catering and sanitary facilities throughout the Austrian highway network, as well as another 55 rest areas equipped with showers and toilets. Most of these facilities, which are often located in remote areas, have their own wastewater pumping station to drain wastewater from the site.
At these stations, the company uses high-pressure technology as standard: conventional wastewater pumps break up solids and pump them through small-diameter pipes (DN50) into the municipal wastewater network. This is a proven and cost-effective solution for wastewater disposal in places where conventional gravity sewers cannot be used.
Changing usage behavior
Gradually changing customer behavior, however, has led to challenges. While conventional wastewater pumps with macerators can operate reliably for many years with minimal maintenance, they are easily overwhelmed by large, sudden volumes of unconventional materials such as wet wipes or diapers. In addition, harder material that cannot be shredded accumulates in the pump sump over time. As more and more of these materials entered the wastewater system at certain locations, the company’s maintenance crews were called in almost weekly to repair clogged pumps.
Yet lifting these pumps out of the wet well and clearing the clog is a costly, messy and time-consuming job. And with no alternative means of sewage disposal, operators often had no choice but to close sanitary facilities at the affected sites during the repair work.
Chopping up the problem
On the occasion of the planning of a new rest area, the facility management department of ASFiNAG asked Sulzer’s wastewater specialists for support in this project. After studying the site, Sulzer engineers recommended a solution with two lines of attack: First, the solids-laden wastewater is passed through a slow-speed Muffin Monster 10K shredder, which efficiently breaks up larger solids before the wastewater reaches the wet well and pumps. Then, two Piranha-type wastewater pumps use their cutting system to break the solids into even smaller particles and create the pressure needed to discharge the wastewater from the site.
The Group built and supplied the pump station as a complete service, designed and engineered the pump control systems, and supplied both the pumps and the macerator. Since the installation in December 2020, there have been no problems with clogged pumps at the site. Based on the success of this installation, the operator has ordered additional Muffin Monsters. These will be installed at other sites, where they will replace systems that remove solids and direct them into containers. This eliminates the cost of container transportation and separate waste disposal.
“Our customers expect our services to be available at all times of the day and night. For us, proactive optimizations like this are part of the continuous improvement of our facilities. The technology has proven to be absolutely reliable, cost-efficient and straightforward.”
- Alexander Holzedl
