Murphy-Brown Feed Quality Training Program - North Carolina State by hcj

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									Batching and Mixing



    Peter Ferket
    Charles Stark
    North Carolina State University
Batching & Mixing Objective

 Accurately weigh each ingredient
 Minimize batching time
 Produce a feed that has a uniform distribution
  of nutrients and medications
EQUIPMENT
Batching Equipment

 Micro Bin Systems
 Tote Bag Systems
 Scales
 Major
 Minor
 Weigh Buggy
Scales
Batching – Scale Fill Test

                               Major & Minor Scales
                                 Fill test evaluates full
                                  range of load cells
                                   Add test weights
                                      Record weight
                                   Remove weights
                        2/3        Fill scale to 1/3 capacity
                                   Add test weights
                                      Record weight
                                   Remove weights
                  1/3              Fill scale to 2/3 capacity
                                   Add test weights
                                      Record weight
         200 lb
                                 Document results
Batching – Manual Weighing

    Weigh Buggy        Platform Scale
Feed Mill Designs




     Pre-batch grind      Post-mix grind




                       Post-pellet blend
    Post-batch grind
Batching – Micro System
Multiple Hopper Scale   Single Hopper Scale
Batching - Totes
    Totes & Scales   Tote Transfer
Batching Sequence                     Major Scale:
  Batching System
                                      Computer draws multiple
                                      bins to the major scale.
                        Micro Scale   Computer switches to one
    Major       Minor                 bin and jogs at the end of
    Scale       Scale                 the each ingredient.

                                        Major Ingredients
                                        Corn/Wheat
                                        SBM
                                        Midds
                                        DDGS
Batching Sequence
  Batching System                     Minor Scale Fill:
                                      Computer draws single
                                      bins to the minor scale
     Major      Minor
                        Micro Scale   and jogs at the end of the
     Scale
                Scale                 each ingredient.

                                           Minor Ingredients
                                           Dical
                                           Limestone
                                           Salt
                                           Lysine
Batching Sequence
  Batching System               Micro Scale Fill:
                                Computer draws single
                        Micro   bins to the micro scale and
                        Scale   jogs at the end of the each
     Major      Minor
     Scale
                Scale
                                ingredient.

                                     Micro Ingredients
                                     Vitamins
                                     Trace Minerals
                                     Medications
                                     Amino Acids
Batching Sequence
  Batching System


                                      Scale Considerations:
                        Micro Scale

     Major      Minor                 Major Scale 80-90%
     Scale
                Scale
                                      Minor Scale 10-15%
                                      Micro Scale < 5%
Batching Sequence
  Batching System
                                      Major Scale
                                      Discharges First
                        Micro Scale   Fills the dead space
     Major      Minor                 between the ribbons
     Scale
                Scale
                                      and tub.
Batching Sequence
  Batching System
                                      Minor Scale Discharges
                                      after a 5-10 second
                        Micro Scale   delay
     Major      Minor                 Minor ingredients mix
     Scale
                Scale
                                      with the major
                                      ingredients
Batching Sequence
  Batching System
                                      Micro Scale Discharges
                                      after a 0-5 second delay
                        Micro Scale
                                      Micro tub or scales open
     Major      Minor                 and the material is
     Scale
                Scale
                                      transferred with a drag
                                      conveyor
                                      Mixing Time
Batching
  Batching System                     Horizontal Double Ribbon
                                      30-60 second Dry Mix
                        Micro Scale   120-180 second Wet Mix
     Major      Minor                 Liquid Addition
     Scale
                Scale
                                      Volumetric (meter)
                                      Gravimetric (weighed)
                                      Liquid Ingredients:
                                      Fat
                                      Molasses
                                      Choline
                                      Amino acids
Batching Sequence                        Discharge Process
  Batching/Mixing System
                                         Mixer opens and
                                         material drops to a
                                         surge hopper
                           Micro Scale

     Major       Minor
     Scale
                 Scale
 Batch Cycle

Weighing 2 min
                               Batch Cycle – 4 mins

                 Discharge
                   1 min

                                Mixing 3 min


                             Weighing 2 min

                                                  Discharge
                                                    1 min

                                                              Mixing 3 min
Automation System
Batch Production Report
MIXING EQUIPMENT
Horizontal Ribbon Mixer
Double Ribbon Mixer – Mixing Zones


                               Feed Flow


                           Main Mixing Zone




                           Main Mixing Zone




  Typical mix time = 3-4 min
Double Ribbon Horizontal Mixer
Paddle Mixer
Paddle Mixer – Mixing Zones


        Feed Flow

       Main Mixing   Some     Main Mixing
                     Mixing




                     Some     Main Mixing
       Main Mixing
                     Mixing
Horizontal Paddle Mixer
Rotating Drum Mixer – Mixing Zones
Drum Mixer
Ribbon Mixer - Counterpoise
Ribbon Mixer – Counterpoise Mixing Zone




                         http://www.hayes-stolz.com/
Forberg Fluid Bed Mixer
Forberg Mixer
Vertical Mixer
Vertical Mixer – Mixing Zones
             Main              Main
             Mixing            Mixing
             Zone              Zone




                      Main
                      Mixing
                      Zone
Vertical Mixer
Mixer Problems

Material on ribbons   Material on paddles
Batching & Mixing Problems

Fat sprayed on ribbon and   Fat lumps created by poor
shaft                       liquid application and mixing
MIXER UNIFORMITY ANALYSIS
Factors Affecting Uniformity
 Particle Shape
   Spherical, square, flat
 Particle Size
   Different particle size can separate during the handling
    process
 Density
   Heavy particles may settle out during conveying and
    discharge to a bin
 Static Charge
   Particles will adhere to equipment if not properly grounded
 Hydroscopicity
   Vitamins or Feed Additives may absorb water
 Adhesiveness
   Fats or molasses may adhere to equipment
What Represents the Goal of Mixing?




                                 Segregated
                                    Mix


   Perfect Mix
                 Random Mix
Weighing Ingredients Correctly?

                  Weighing Accuracy
 Feed mills overdose their ingredients by about 1.5%
 Average inaccuracy in dosing within feed mills ranges from
  0.7 - 13.0%
 About 85% of the calls are weighted with an error of ± 5% and
  about 90% are within ± 10% of called weight
Distribution of weighing errors
Overdosing and weighing errors
error within mill (a-n) across all observations
Are You Weighing Ingredients Correctly?


             Weighing Precision
 Variation in weighing within ingredients, expressed
  as Coefficient of Variation (CV)
 Weighing CV ranges on average of about 5% (0.6 -
  11% CV)
Causes of Weighing Variation
 Hand-weighing ingredients
    People tend to overdose by about 1% when ingredients are weighed by hand

 Micro-ingredients and premix dose errors
    Micro-ingredients scales seem to be more variable than macro-ingredient scales
     because of the size of the call

 Descrepancies between call size and scale resolution
    Average weighing discrepancies in feed mill is about 2% but can range up to 20%
    For example, requesting 11.3 lbs of an ingredient when the scale has a resolution
     of only 2 lbs.

 Ratio of call size to scale resolution
    Weighing errors and CV decreases as the call size to scale resolution increases.
     For example, a call for 100 lbs to be weighed on a scale with a resolution of 5 lbs
     gives a call/scale resolution of 20, where as a call for the same 100 lbs on a scale
     with a resolution of 2 lbs gives a ratio of 50.
Weighing errors and CVs for different call
size to scale resolutions
   Call Size:Scale   Weighing Error, %    CV, %
  Resolution Ratio

        10                  4.0            11.4

        100                 1.0             3.6

       1000                 0.3             1.1




                                    Experimental Data
Mixer Uniformity Analysis
  Mixer Markers
    Single nutrient/ingredient
      Salt
      Synthetic Amino Acids (Lysine or Methonine) Dry Mix Uniformity

    Economical
    Accurate and precise at inclusion level
  Test twice per year
  Ten samples from the same batch of feed
  Sample mixer or a point closest to the
   discharge
Mixer Uniformity Analysis
 Sampling Points
 Mixer or Surge samples provides information on
  dead spots in the mixer or mixer maintenance
  issues

 Sampling during the discharge process provides
  representative samples of the feed as it moves
  through the system.
Feed Quality Assurance – Mixer Test
                      Sample mixer
                       OR
                      Sample surge
                       OR
                      Sample discharge
                       conveyor
Mixer Uniformity Analysis - Quantab™
Mixer Uniformity Analysis - Quantab™

                      Weigh 10 gram
                       sample of feed into
                       a dish
                      Scale +/- 0.1 g
Mixer Uniformity Analysis - Quantab™
         Fold filter paper to create a cone
Mixer Uniformity Analysis - Quantab™

                      Measure out 90 ml
                       of HOT distilled
                       water
                      SAFETY
                       Hot Water Burns!!
Mixer Uniformity Analysis
                       Mix sample and water
                        for 30 sec wait and
                        re-mix for 30 sec.
                       Place filter paper
                        cone in cup
                       Place Quantab strip
                        into the filter cone
                       Indicator strip at the
                        top will turn black
                        when complete
Mixer Uniformity Analysis - Quantab™

                      Read highest point
                       on the strip
                      Determine NaCl
                       level based on the
                       calibration chart on
                       the bottle.
                      Multiple by 10
                        (10:1 dilution)
Mixer Uniformity Analysis Calculations

 Calculation of Mixer CV
 Mean of samples
 Standard deviation of samples

 CV % = standard deviation x 100
              mean
Mixer Uniformity Analysis Calculations
       NAME:                  DATE:
       ADDRESS:
       SAMPLE:

       QUANTAB READINGS

          1       0.20
          2       0.21
          3       0.22
          4       0.17
          5       0.17
          6       0.18
          7       0.20
          8       0.17
          9       0.18
         10       0.18

                       0.02
       STANDARD DEVIATION
       MEAN            0.19

       COEFFICIENT OF VARIATION (CV)   9.65
Mixer Uniformity Evaluation

 CV          RATING   CORRECTIVE ACTION
 < 10%    Excellent   None

 10-15%   Good        Increase mixing time by 25-30%

 15-20%   Fair        Increase mixing time by 50%, look for worn
                      equipment, overfilling, or sequence of
                      ingredient addition
 20% +    Poor        Possible combination of all the above
                      Consults extension personnel or feed
                      equipment manufacturer
Double Ribbon Mixer – RPM’s
Double Ribbon Mixer – Worn Ribbons
Double Ribbon Mixer – Wrong Rotation
Double Ribbon Mixer – Build-Up
Questions

								
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