To keep wastewater operational costs and downtime to a minimum, operators expect a high level of reliability from pumps - even during incidents of heavy rain. This is an important aspect in these times of increasingly marked climate fluctuations. High degrees of efficiency are also expected from pumps so that wastewater can be pumped through the wastewater pipes and sewers energy efficiently while conserving resources.
Plant operators are also facing entirely different challenges. Population habits have changed, with water consumption in households having dropped severely during the period from 1990 to 2004 by approx. 14 percent. Peoples' habits with waste are also changing. Waste and refuse are increasingly landing in the sewer system although they have no business being there. Items such as:
- Wet wipes or “flushable” wipes, cosmetic wipes and baby wipes
- Disposable cleaning cloths
- Cotton swabs
- Tampons and panty liners
- Clothing and textiles
- Plastic bags, plastic debris
Incorrect disposal methods via the wastewater pipe are causing problems
In particular, the sale of wet wipes has increased rapidly by around 200% over the past few years. Whereas in the past they were used almost exclusively for baby care and were disposed of as household waste together with diapers, wet wipes and cosmetic wipes, they are today part of day-to-day hygiene and are increasingly landing in sewage pipes. It is easy to see why wet wipes are causing such problems: More and more fibers are entering the sewer system but with less and less wastewater. This combination is leading to pumps clogging and increasing wastewater fees for consumers. Few people are aware that legal regulations prohibit the disposal of wet wipes or similar items via the toilet. Notes on wet wipe packaging informing consumers that they should be disposed of via household waste are often lacking or else written very small. In addition, they are often in places where consumers can overlook them easily. Other modern hygiene items like clothing and textiles are also increasingly being disposed of via sewage pipes.
Fibers as a cause of clogging of pumps, screens and wastewater pipes
Once they get into the sewer system, sanitary products like panty liners, and textiles like cloths and wet wipes become a problem for wastewater technology. Wet wipes are neither easy to separate nor can entangled wet wipes be prevented very easily. Instead, components regularly fail due to their presence, with entangled material causing clogging of pumps, valves and wastewater pipes. Even pumps developed by industry with freewheel -- a large spherical passage -- can only handle these entangled materials and the resultant clumping to a limited degree. Operating companies therefore have to combat a significant drop in efficiency with pumps equipped in this way.
Wet wipes - how the right wastewater technology prevents the clogging of pumps
Entangled material from sanitary items can generally be prevented only if they are shredded or pass through a grinder prior to reaching the pump. One economic variant for reliable protection from clogging of pumps and wastewater pipelines are twin-shaft grinders. These wastewater grinders are designed based on a contactless principle of operation, which is why their power requirements during idle running is minimal. Thanks to low speeds, large torques are made available for grinding, enabling these devices, even with a low drive power, to prevent the clogging of pumps or wastewater pipelines. For many operators, the investment in a technique of this type pays for itself within a very short time. Electricity consumption and hence operating costs of the pumps drop, sparing cost-intensive maintenance and service visits, as well as emergency maintenance at nighttime or on public holidays to free up entangled material in the pumps.
One important aspect when using wastewater grinders in the sewer system is harmonization with downstream technology. The grinding process must be fine enough for the shredded fragments to pass through pumps and valves without any problem. At the same time, fragments must remain large enough so that they can be reliably separated by downstream screens and not enter the sewage treatment plant. In order to guarantee this, various cutting tools are required. XRipper’s ripper rotors are manufactured from a single piece, resulting in long service life and other considerable benefits when compared to systems consisting of individual cutting blades and spacers. Besides a wear-resistant, hard surface, they offer better force transmission with a minimized risk of breakage due to foreign matter like metal parts, etc. And thanks to narrow tolerances, the grinding process is more efficient and less drive power is required.
An important criterion when selecting a wastewater grinder for the protection of pumps and screens is a high level of availability and operational readiness. Instances where the entire shredder needs to be removed and even sent away for replacement of parts are counterproductive. This is particularly the case when an overhaul might take several weeks. This is why the XRipper wastewater cutter is designed for our QuickService concept: All service and maintenance work can be performed by your own staff on site in a short time without any long interruptions to service.