Abstract SYMPHOS 2011

PH-O-16
Todd Hutchinson
Director of Research & Development, Philadelphia Mixing Solutions, Ltd.,
1221 East Main Street, Palmyra, PA 17078, USA
Mixer designs for Phosphoric Acid reactor applications are often specified to a fine level of detail in technical
specification documents. The specifications are written with some requirements being stipulated along the
guidelines of design norms such as AGMA for gearbox service factors and ABMA standards for bearing life. Other
specifications are dictated per licensor requirements. Among the items that could be licensor defined are agitator
shaft as well as impeller designs.
The demanding nature of the processes in Phosphoric Acid reactors, irrespective of design technology (Prayon,
Dorrco, Yara etc.), further lead to engineers and plant owners demanding that the mixers be designed with
sufficient mechanical integrity to operate under “Phosphoric Acid Service” conditions.
Philadelphia Mixing Solutions, Ltd. embarked on our work to find an optimal design solution for mixer duty in
Phosphoric Acid reactors by first understanding what precisely “Phosphoric Acid Service” duty meant in terms of
process behavioral impact and then how that influenced mechanical design considerations for the mixers employed
in this duty.
This paper is written based on case study evaluations performed at a Phosphoric Acid plant in the Western
Hemisphere. The root causes behind the mixer failures were identified after studying the typical symptoms of
problematic mixer performance. Design solutions were implemented resulting in measurable overall process
improvements (less scaling / solids buildup). The changes made further allowed for longer continual operation
between vessel cleanings and reduced erosion wear on the impeller blades.
64
OPTIMIZING AGITATOR DESIGN FOR PHOSPHORIC ACID REACTOR DUTY
Jean Noël FERNANDEZ
Mersen, Brignais FRANCE
MERSEN MIXERS : AN INNOVATIVE DESIGN COMBINING PROCESS
OPTIMISATION AND ENERGY EFFICIENCY
PH-O-17
Mersen is a leading multinational industrial group. With its extensive expertise in high-grade materials and
electrical installation reliability and security, Mersen designs innovative solutions tailored to customer requirements
to improve their industrial performance in sectors such as energy, transport, electronics, chemical/pharmaceuticals
and process industries.
Its Process Equipment Division is internationally recognised for its expertise in the design and manufacture of
equipment made from high-grade materials for use in corrosive and hot environments.
For over 50 years, Mersen has been designing and manufacturing mixers for water, chemical and hydrometallurgy
processing.
With its solution-oriented approach, it has developed a range of mixers specially designed for the
phosphoric acid and fertiliser market.
Our 30 years of experience in this field have enabled our research and development teams to create a range of
mixers that improve process performance and energy efficiency. Their innovation essentially focuses on the
hydraulic and mechanic design and their development is based on calculations and simulations generated
by our in-house software.
The know-how of our engineering department and our expertise in noble materials make Mersen a key player in
the design and manufacture of mixers for use in extreme environments. Its industrial plants in Morocco (2,500m²),
France (8,000m²) and China (150,000m²) confirm our international position as the leading supplier of process
equipment for the phosphoric acid and fertiliser market.