dry and wet sieve analyses - fluid quip technologies · all contents are to be considered...

All contents are to be considered confidential and proprietary work product of FQT. © 2019 Fluid Quip Technologies, LLC. All rights reserved.

Don Cannon, Ph.D., QA/QC Lead

Midland Scientific Fuel Ethanol Laboratory Conference

La Vista, NE, October 22, 2019

Dry and Wet Sieve Analyses


• Liquefaction

• Viscosity

• Hydration

• Starch release

• Break open germ

• Enzyme access

• Fermentation

• Enzyme access

• Settling and agitation

Wide Ranging Impacts of Particle Size

Particle sizing, typically with sieves, is usually a routine part of QA/QC program

• Post-Fermentation Processing

• Distillation

• Decanters

• Evaporators

• Oil recovery

• Release of protein from fiber

• Dry solids

• Bulk density

• Flowability

• Explosibility


Grain Pans: Grain specific check of general quality

https://www.meshsieve.com/


Grain Pan: Broken Kernels and Foreign Material %

https://www.gipsa.usda.gov/fgis/visualref/principle_grain_vri/principle_grain_vri_MAIN_p003.htm


Sizing Sieves: Quantitation of Particle Sizes

https://www.formtest.de

“Laboratory sieve features high precision, accurate mesh, acid and

alkali resistance, ideal for all kinds of powders and particle analysis.”

https://www.endecotts.com/products/sieves/wet

-washing-sieves/product-specifications/


Sieve Sizing: Mesh (#) micrometer (micron) openings

http://www.bionicsscientific.com/sieve-shakers/test-sieves.html


• Variety of sieve shaking equipment

• Vibrations through mechanical means

• Ro-tap can be calibrated via tap stroke

• Consistency is key

• Don’t overload system capacity

• 8” sieves – 3-5 pans – 100-150g

• Blinding caused by particle aggregation

• Oil content is primary factor

• Can be minimized via plastic balls (10/pan)

• Sieve cleaning – dry brush, compressed

air, flowing water, or ultrasonic cleaning

Sieve Shakers


The Size of Corn ComponentsStarch Structure


185°F

195°F195°F

+ shear

Native165°F

The Size and Composition of Starch


The Size of Corn Components

https://en.wikipedia.org/wiki/File:Cellulose_spacefilling_model.jpg

https://www.news-medical.net/life-sciences/Supramolecular-

Assembly-and-Supermolecules.aspx

Molecular Structure of Cellulose

Supermolecular Structures


DDGS Sieving


DDGS Size Fractions – Plant 1

+20# -20# +35# -35# +50# -50# +100# -100#


DDGS Size Fractions – Plant 2

+20# -20# +35# -35# +50# -50# +100# -100#


+20# DDGS Size Fractions


Selective Grind Technology™ (SGT™) Overview

• Installed in slurry / liquefaction

• Dewater mash in paddle screen

• cake to selective mill

• liquid bypassed to mixing tank

• Secondary milling step – 36”, 40”, 52” Mills

• 3rd grind from wet mill

• optimized grinding plate design

• autogap adjustor for grind consistency

• Mixing tank combines cake and liquid streams


Selective Grind Technology™ (SGT™) Overview

• Selectively grind large particles

• without creating a lot of fines (<50 um)

• Focus on reduces particles to less than 850 um

• Hammer mills leave large particles - #6 screens

are 2286 um

• Release and hydrate starch in liquefaction

• Breaks open germ

• Releases protein from fiber


Process Steps for Simulating SGT™

1. Dewatering (paddle screen simulation using USA Standard sieve screens)

• Selection of mesh sieve size

• particle size distribution, moisture level, temperature

2. Selective grinding (disc grind simulation using a flat-blade mill)

• Particle size analyses on wet-cake material

• type of mill, time, agitation

3. Fermentation (assessing enzymatically available starch via saccharification)

• Rapid assessment using alpha-amylase and glucoamylase dosing

• real-world substrates (versus optimized buffer-based starch methods)

• post-saccharification centrifugation provides oil recovery potential


Quantitating Particle Size in Mash

• Particle size distributions across five different 3” dia. sieve size ranges (>850, 850-500, 500-300,

300-150, and 150-45 um) as a percentage of total solids larger than 45 um retained per pan

850 um (#20) 45 um (#325)


Wet-wash sieving


• Start with known amount of material

• Rinse all material over a given size sieve screen

• Use lots of hot water…Increase flow over wash duration

• Use spoon to disperse water and mix sample…not to push material through

• Careful not to overflow wash water until blinding is washed through

• Check progress by looking at effluent stream for passing particles

• Weigh aluminum pan + coffee filter

• Place retained material into coffee filter

• Fold coffee filter and squeeze out liquid using hands

• Be sure to collect all material…Use water to rinse material back to an amount that can be transferred

• Dry in oven at 105C for several hours, weigh immediately after taking out of oven

• Data analysis

Wet-washing General Procedure


Quantitating Mash Particle Size

• Particle size distributions across five different 3” dia. sieve size ranges (>850, 850-500, 500-300,

300-150, and 150-45 um) as a percentage of total solids larger than 45 um retained per pan

• This ratio (normalization) to >45um allows for plant-to-plant comparisons

Sample IDSieve Screen

(mm)

Drying Pan

Weight (g)

Initial Sample

Weight (g)

Sample Dry

Weight (g)

Sample End

Weight (g)

Recovered Solids

per Pan (%)

Solids per Particle

Size Range (%)

Particle

Size Range

850 2.49 53.55 4.06 1.57 2.9 37.4 > 850μm

500 2.47 51.37 5.14 2.67 5.2 28.9 500 - 850μm

300 2.49 51.45 5.77 3.28 6.4 15.0 300 - 500μm

150 2.46 47.40 5.86 3.40 7.2 10.2 150 - 300μm

45 2.42 49.17 6.27 3.85 7.8 8.4 45 - 150μm

Liq 1


Quantitating Mash Particle Size

➢ Hammermill screen size

was 7/64”

➢ Hydroheater between

slurry 2 and liquefaction

➢ Results align well with

laser light scattering

particle size analysis…

but not as resolved.


Verifying Selective Grind Simulation: Particle Size

pre- and post-SGT™ at plant SGT™-plant vs. SGT™-sim


Summary and Acknowledgments

• Particle size has many impacts on grain processing

• Particle size ranges can be routinely evaluated (QA/QC’d) on dry and wet material

• Variety of issues can contribute to “highers” seen in dry products

• “Fines” (<45um) are not capable of accurately being measured in dry products

• Wet-wash sieving gives unique insights into in-process samples

• Thanks to all that we’ve worked with at the various dry-grind facilities

• Thank you for your attention!

• [email protected]

dry and wet sieve analyses - fluid quip technologies · all contents are to be considered...

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