— The APPLICATION
Wastewater management
In the liquid waste management sector, major specialized companies are frequently called upon to provide collection, transport, and delivery services for wastewater with a high content of coarse solids, particularly sand, to their authorized treatment plants.
Among the most common activities is the emptying and cleaning of tanks, collectors, and sewer systems for maintenance purposes. These operations are carried out using tankers equipped with high-pressure washing systems and high suction capacity.
Once the unloading operation at the destination plant is completed, the tankers must in turn undergo a thorough internal washing. This step is essential to remove the sandy residues that tend to settle on the bottom of the tank and which, if not removed, could compromise subsequent loading and transport operations.
— The SOLUTION
ST-R4 D11 self-priming centrifugal electric pump in hardened cast iron
To meet this need, the creation of dedicated sections for tank washing, known as "door cleaning" areas, at liquid waste treatment plants is becoming increasingly widespread.
In these systems, the tank is opened completely at the rear to allow for thorough internal washing. The wash water, loaded with sand and coarse solids, must therefore be managed using a system capable of effectively separating the liquid phase from the solid phase, with the related management of the resulting residues.
In these contexts, the handling of abrasive slurries requires robust, reliable pumping solutions constructed from highly wear-resistant materials. Varisco's ST-R pumps, in the D11 configuration (made of hardened cast iron with a hardness between 380 and 420 HB), have proven to be an optimal choice for dealing with these harsh conditions.
A concrete example is represented by B. Energy SpA, an Italian major waste treatment company recently installed a Varisco ST-R4 D11 pump in a new facility dedicated to the "door-cleaning" and cleaning of tankers transporting non-hazardous liquid waste of civil origin containing sandy residues.
This experience confirms how a targeted choice of pumping technologies represents a key element in ensuring operational continuity, process efficiency, and reduced maintenance costs in modern liquid waste treatment platforms.
