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Abstract Submission Topic : / EPIC5 / Plant intensification A NEW SUPERIOR MIXER-ACTIVATOR FOR ENHANCING CHEMICAL REACTIONS Pasi Tolvanen* 1, Henrik Grnman1, Carl-Olof Palm2, Tapio Salmi1 1Laboratory of Industrial chemistry and reaction

  1. Abstract Submission Topic : / EPIC5 / Plant intensification A NEW SUPERIOR MIXER-ACTIVATOR FOR ENHANCING CHEMICAL REACTIONS Pasi Tolvanen* 1, Henrik Grénman1, Carl-Olof Palm2, Tapio Salmi1 1Laboratory of Industrial chemistry and reaction engineering, Åbo Akademi, Turku, 2Megatrex, Megatrex, Lempäälä, Finland Authors of the abstract come from :: Both University and Industry Many industrial applications deal with solid-liquid interactions where an enormous amount of energy is required to obtain the desired mixing or homogenization. The conventional stirring-and-waiting methods could be drastically improved if the amount of time and energy (high temperatures and pressures) could to some extent be avoided. A new innovative mixing technology Atrex has recently obtained attention in industries around the world due to its excellent capabilities – minimal time of processing and energy is required. The main benefits of using Atrex are: - continuously operating industrial high shear mixing - suitability for grinding and crushing, as well as dispergation and disintegration - multiple repeated impact strikes and over- & under pressure pulses - strong tribomechanical and tribochemical activation for enhancing reactions Atrex is a continuously operating industrial process equipment consisting of counter-rotating (typically1500rpm+1500rpm) pinned discs for crushing, grinding, mixing, micro-homogenization and disintegration with very strong shear forces, turbulence and huge amounts of repeated impacts and over/under pressure pulses [1] . All ingredients contribute to superior surface activation properties. Strong centrifugal forces give an easy input and output of processed materials, and the mixing time in Atrex is less than one second and every single volume unit gets a similar strong energy input. The equipment is small in size but the capacity is high. The strong activation properties of Atrex could be further improved by applying a stimulating radiation for a selective exitation of reacting atoms, molecules and ions (light, heat, pressure, microwave, electric, magnetic) to react efficiently. Typical processes such as scrubbing, flotation and precipitation, can be significantly enhanced. Several existing patents of the technology exist. The alkaline extraction of hemicellulose by conventional ways require a large input of energy and long reaction times [2]. Therefore, this reaction was selected as a model case to illustrate Atrex efficiency. A bench-scale Atrex equipment was used for extraction of valuable components from wood material. As main components in the experiments, hot water and alkali were used. With hot water extraction, hemicelluloses are obtained selectively from the wood material, whereas lignin is selectively extracted with alkaline-water solution. The results showed that the process can be considerably intensified by applying the Atrex equipment, compared to conventional hotwater and alkali extraction processes. 1

  2. A N A New ew Superior Superior Mix Mixer er-Act Activa ivator tor for Enhanc or Enhancing Chem ing Chemical ical and and Physical Physical Pr Processes ocesses Pasi Tolvanen 1 ,Carl-Olof Palm 2 , Henrik Grenman 1 , Tapio Salmi 1 1Åbo Akademi, Turku/Finland, 20500-Fi, ptolvane@abo.fi 2 Megatrex Oy, Lempäälä, Finland EPIC-5 - 29th September 2015 2

  3.  Many industrial processes are slow and/or, or consist of several steps:  Disintegration & homogenization  Gas scrubbing  Precipitation  Solid-liquid mixing  Extraction processes (stirring-and-waiting)  Drying steps between treatment /reaction EPIC5 - P. Tolvanen - 29.09.2015 3

  4. These slow processes can be improved - reduce processing time - reduce energy consumption - reduce number of processing steps Need highly efficient simultaneous mixing & grinding technology EPIC5 - P. Tolvanen - 29.09.2015 4

  5.  A new mixing/grinding technology  A continuously operating industrial high-shear impact mixer  contra-rotating pinned discs  Strong shear forces and attrition  High turbulence and repeated impacts  Alternating over/under pressure pulses  Horizontal rotor position  Easy feed of reagents and exit of products by strong centrifugal forces Strong activation by Enhancement of repeated collisions slow processes and virgin surfaces 5

  6. The impact crusher-mixer-grinder-activator  2 discs with several concentric rows of pins  Discs rotation normally from 500 to 1500 rpm  Contra-rotating discs normally 1500 rpm + 1500 rpm  Mixing time less than one (1) second  Strongly activated * ) virgin surfaces allow direct contact and reaction *) Tribomechanical and – chemical activation EPIC5 - P. Tolvanen - 29.09.2015 6

  7. Successful industrial application examples of Atrex mixer  Dispersion of pigments paint & paper industry  Disintegration of paper making rejects - up to 97% recirculated  Dry grinding of natural polymer  Gas scrubber  Simultaneous continuous crushing, grinding and wetting in lime slaking process within minutes to dry product or colloidal lime milk  New development - Hot water e xtraction of hemicellulose from wood EPIC5 - P. Tolvanen - 29.09.2015 7

  8. Example: Scrubbing A conventional scrubber process is slow with extremely low collision probability due to flow dynamics (picture) R B water droplet ϕ : 10.000-1.000.000 nm dot in text : 500.000 nm ν p ϕ T smoke : 100-1000 nm ν p droplet SOx molecule : 1 nm h 0 Stagnation line R P Atrex Forced collisions g - Enhanced interactions Dust, soot  faster process particles and Fluid stream molecules in a  smaller device lines gas flow follow  larger treated volume the main flow R c . . . . . . . .

  9. Normal slaking of quick lime – a cumbersome chemical & physical process! CaO (s) + H 2 O (l) → Ca(OH) 2 (s+l) + heat  Highly exothermic  lot of process water is needed for safety  Protective layers of hydrated lime forming on unreacted quick lime retarding the process  Agglomerated wet product must be dried and unwanted large crystals are precipitated from solution  Further grinding, separation and handling in air carbonate surfaces retarding reactivity of the product Using Atrex slaking  Rather big lumps (~5 cm) are simultaneously crushed, ground and wetted and the violent reaction is performed safely in a closed process directly to nanosized products  Dramatic enhancement of the slaking process EPIC5 - P. Tolvanen - 29.09.2015 9

  10. Newest study: Extraction of hemicelluloses Spruce-derived galactoglucomannan (GGM),  Potential to be utilized in a wide assortment of products, ranging from the food industry to cosmetics, fine chemicals , and biocomposites Conventional hemicellulose extraction: - Hot water - Reaction time - Large water quantities Part of hemicellulose molecule EPIC5 - P. Tolvanen - 29.09.2015 10

  11. ሶ  Atrex based hemicellulose pilot Starting wood chips inlet extraction method Recirculation loop total 120 min One round = 2 minutes Pump Atrex Temperature 90 º C P TIC Q mixer heater Increased extracted hemicellulose over time sampling 11 10 15 1 ...120 min 5

  12. Extraction results Total hemicellulose extracted to aqueous phase Breakdown of monomer products 1,8 7,00 Ara(Sum) Gal(Sum) 1,6 yield hemicellulose (%) GalA(Sum) Glc(Sum) 6,00 1,4 GlcA(Sum) Man(Sum) 5,00 1,2 Rha(Sum) Xyl(Sum) 4,00 1 yield % wt.-% 0,8 3,00 Δ c R / Δ t 0,6 2,00 faster initial rate than 0,4 conventional extraction 1,00 0,2 0,00 0 0 20 40 60 80 100 120 140 0 50 100 150 time (min) time (min) Yield 5x higher than conventional extraction process at 90 o C

  13. Disintegration of the fibers within minutes Reaction time: 0 min Optical microscope Reaction time: 2 min 13 Reaction time: 20 min Reaction time: 60 min

  14.  Progress of mannose extraction 15 (GC analysis) 5 2 minutes EPIC5 - P. Tolvanen - 29.09.2015 14

  15. Conclusions The Atrex activator mixer-grinder provided by Megatrex works efficiently in a broad area  of industrial process intensification Hemicellulose extraction gave promising results – the initial extraction rate is higher  than in the conventional extraction equipment even at much lower temperature.  It was found out, that the extraction velocity using Atrex was 5 times faster than conventional extraction operated at 90ºC and 2 hours of reaction, using spruce as a source material.  Sugars from wood and other lignocellulosic material can be more easily extracted for industrial processes Further studies - pressurize the reactor system, higher T.  EPIC5 - P. Tolvanen - 29.09.2015 15

  16. Acknowledgements Acknowledgements:  Megatrex  Åbo Akademi University  Additional ECCE info + photos can be found: http://www.ecce2015.eu/ EPIC5 - P. Tolvanen - 29.09.2015 EPIC5 - P. Tolvanen - 29.09.2015 EPIC5 - P. Tolvanen - 29.09.2015 16 16 16

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