What is your application?
Our expert is familiar with the processes in your industry and will be glad to advise you!
STÜBBE X-CLASS centrifugal pumps for highly abrasive ferrous sulfate
Case study on the STÜBBE E-CLASS and STÜBBE X-CLASS
Case study at a glance
- Extraction of ferrous sulfate as a waste product
- Highly abrasive substance requires resistant solution
- Chemical plant makes use of STÜBBE's expertise
- Use of STÜBBE X-CLASS heavy-duty centrifugal pumps
The challenge
Waste product ferrous sulfate (highly abrasive)
VENATOR produces TiO2 pigments based on a sulfate process at its location in Uerdingen. For this process, ores containing titanium dioxide such as ilmenite and preprocessed titanium slag are made to react with concentrated sulfuric acid. The metal oxides contained in the ore are largely dissolved as sulfate salt After ilmenite solution containing Fe (III) is mixed with a slag extraction solution containing titanium (III), a solution that is virtually free of solid particles and has precisely specified contents of TiO2, Fe2+, Ti3+ and H2SO4 is produced by sedimentation and filtration. TheTiO2 contained in the solution is subsequently precipitated out by hydrolysis with water. In order to be able to use as much ilmenite solution as possible, it is concentrated in an intermediate step using the crystallization plant.
VENATOR produces TiO2 pigments based on a sulfate process at its locaCentrifugal pumps are used in the continuously operating crystallization plant, and are subjected to extremely abrasive wear, which means they have to be regularly repaired or replaced. Following reduction, sedimentation and filtration, the extraction solution is cooled down in two inner catalyst tube crystallizers by means of precooling and vacuum crystallization. During this process, the solution becomes supersaturated with the iron sulfate. The crystallized iron sulfate heptahydrate is separated from the mother liquor by centrifuges and rinsed with diluted sulphuric acid. The ferrous sulfate treated in this way is transported by screw conveyors and conveyor belts to the warehouse.
The STÜBBE solution
Expertise, new methods and the STÜBBE X-CLASS
During the process, a certain amount of of precipitation of ferrous sulfate and encrustation on the inside walls of the crystallizers and pipework can simply not be avoided. In order to ensure that the encrustation does not build up and pose a risk to operation by spontaneously and uncontrollably detaching from the wall of the crystallizer, the crystallizers have to be cleaned at regular intervals to remove the encrustation. Unexpected downtime due to failure of the previously used pumps was an added and extremely annoying expense.
With more than 70 years of experience in the processing of plastics and in expert on-site consultation, STÜBBE was confident that it would be able to offer solutions to considerably increase the service life by using the X-class pump made of plastic. In the first step, STÜBBE specialists came up with an extremely unusual and surprising measure: Increasing the speed by reducing the diameter of the pressure line. The idea behind this: Self-cleaning effect due to optimal flow velocity. As blockages were to be expected, STÜBBE suggested the use of an X-class pump with a unique 3-channel free-flow impeller (Vortex), which immediately achieved a longer service life. In the second step, in preparation for an upcoming increase in production and with the knowledge that the particles size would permit the use of more efficient impellers, the system was converted to a new pump size with semi-open standard impeller and annulus housing.
The result
Tripling of service life since introduction of the STÜBBE X-CLASS pump
VENATOR’s willingness to put its trust in STÜBBE's experience and professional expertise, even when STÜBBE suggested some unusual measures, led to a three-fold increase of the pump service life compared to the original make of pump.
VENATOR is not just convinced by the safety and reliability of STÜBBE's new X-CLASS pump, but also by the customer service and professional consultation for such complex applications.
Products of this case study
Download this case study as pdf
The PDF of this case study is freely available. Further case studies with solutions for applications in various industries can be found here.
PDF Download
PDF file, 4 pages, 8.9 MB
René Junkereit
Expert for industry solutions
Outside Sales
Available via phone: Monday through thursday 8 AM to 5 PM and fridays 8 AM to 4 PM.
©
STÜBBE GmbH & Co.KG
