1) Batching Methods (Add Weigh or Loss In Weight) based on batch dispensing time, time between batches, head room, floor space, accuracy and budget.

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1 Batching Batching Product Overview SELECTION DECISIONS 1) Batching Methods (Add Weigh or Loss In Weight) based on batch dispensing time, time between batches, head room, floor space, accuracy and budget. 2) Transfer from main storage and method of filling feeder storage. 3) Integral Feeder Hopper Storage Volume: if Add Weigh - volume is only dependent on feed mechanism and hopper agitation ability to discharge ingredient. if Loss In Weight - volume is dependent on batch accuracy of each ingredient relative to scale capacity. 4) Feed Mechanism: - feed rate based on batch time (to feed ingredient): - if simultaneous feeding - feeders are smaller in capacity: - based on ingredient feed characteristics and bulk density: - options include screw, twin screw, belt, vibrating tray, and pump (with appropriate agitation determined by experience or testing). 5) Refill Device and Rate: - LIW refill rate sized based on refilling integral feeder hopper after each batch within the time allowed between batches - Add Weigh - normally refill can occur at any time - ability of refill device to physically fit into space allocation - depends on supply - (bag, big bag, carboy, drum, bulk). 6) Physical layout of feeders relative to the batching hopper or batching transfer device to the process. (See Sketch 1). 7) Transfer from Batching Hopper to Process Mixer (if feed is not directly to process mixers). 8) Control Type: simultaneous preferred or sequential acceptable: - if add weigh scale is sensitive: enough to batch minors accurately: - single or multiple weighing per batch (can affect weigh hopper volume) - recipe entry by operator manually or computer storage: - batch initiation - manually or automatic: - batch abort - disposal of batch: - batching problem troubleshooting: - refill initiation - setting batching feed rate - max. feed/dribble feed/handling in flight/jogging: - batching weight record requirements: - print out records for each batch : - local controls at feeders/control room control/central control. 4/03 Supersedes (4000-C26-1) 8/98 Page 1 of 8 Document: 6000-C24-1

2 ADD WEIGH BATCHING VOLUMETRIC FEEDER TO WEIGH HOPPER Volume tric Feeders Ingredients Added In Layers Batch Weigh Hopper MIXING REQUIREMENT INCREAS ED To Batching Process Ingredients are layered and the weigh hopper is simply dumped. Each ingredient feed must be sequential. Feed rate is calculated based on each ingredient being sequentially fed during allowable batch make up time. Control is by weight, the feeder feeds ingredient until proper weight is reached. Fast feed/dribble feed is normal for each ingredient. Dribble feed should be 15 seconds minimum for accurate feeding. Accuracy is a function of total batch weight of all ingredients. Minors may not be batched accurately. If this is the situation, then the minors can either be: (a) hand added (b) loss in weight added (c) utilize a separate add weigh hopper for minors 4/03 Supersedes (4000-C26-1) 8/98 Page 2 of 8 Document: 6000-C24-1

3 LOSS IN WEIGHT BATCHING LOSS IN WEIGHT FEEDER DIRECTLY TO BATCH PROCESS OR BATCHING HOPPER Loss-In-Weight Feeders Ingre die nts Premixed if Fed Simultaneously Batching Hopper (If required), or Funnel to Process MIXING REQUIREMENT REDUCED To Ba tching Process Ingredient dispersed together if fed simultaneously Feed rate is controlled (at a desired rate) during batch dispensing Each ingredient is normally fed simultaneously. Feed rate is calculated based on each ingredient being fed during allowable batch make up time. Control is by weight. The feeder feeds ingredient until loss in weight hopper weight has reduced by batch amount. Fast feed/dribble feed is normal for each ingredient. Dribble feed should be 15 seconds minimum for accurate feeding. Accuracy is a function of LIW scale capacity 4/03 Supersedes (4000-C26-1) 8/98 Page 3 of 8 Document: 6000-C24-1

4 . Batching Product Overview BATCHING SYSTEM ALTERNATIVES AND DESIGN DECISION ADD WEIGH: Advantages: ADD WEIGH VERSUS LOSS-IN-WEIGHT 1) Cost effective method since it requires one or two weigh scales (major/minor) for a number of ingredients. 2) Dry feeder storage does not have to be weight isolated from the dry feeder and as a result can be as large a volume as the feeder can accommodate. 3) If the dry feeder storage is contained in 2 separate hoppers (feeder storage above the integral feeder storage) the isolation valve can be manually actuated and can be maintained open during feeding. 4) Refill of storage hopper can occur anytime without affecting batch make up. 5) If the process requirements result in a long time between batches, compared with actual batch dispensing time, then add weigh is preferred method since feed mechanism feed rate capacity can be lower than loss in weight. Disadvantages: 1) Accuracy is based on scale capacity x scale sensitivity. If one scale is used, the accuracy of minor ingredient batch addition may not be within tolerance. Solution may be to use Micro Batch. 2) Ingredients from volumetric dispensing devices must all discharge to one (or two) common hoppers or use Batch Master. 3) Ingredients must be added to the weigh hopper sequentially, increasing the batch make up time or increasing the volumetric dispensing unit feed rate. 4) Ingredients are layered in the weigh hopper. 5) Ingredient residue may adhere to weigh hopper. LOSS-IN-WEIGHT: Advantages: 1) Accuracy is based on the ingredient feeder scale capacity. As a result minor ingredients can be added at high accuracy independent of major ingredient batch size. 2) If there are several ingredients, each discharges independently with no requirement to feed to a common weighing point. 3) The ingredients can be discharged simultaneously to produce the total batch, some pre-blending may occur as a result. 4) If discharge is directly to the process: a) head room requirements may be decreased: b) there is no adherence of the ingredient to an intermediate hopper, container or transfer device (or piping). 5) If the dispensing time is compared to time between batches, it is the preferred method. Disadvantages: 1) There is an added cost for multiple ingredients since each ingredient has its own scale. 2) The dry feeder storage is limited to scale capacity. If more feeder storage is required it must be isolated from the feeder weigh hopper with automatic refill occurring after each batch or as required. 3) Refill of feeder weigh hopper cannot occur while a batch is being discharged, as a result, there must be sufficient time between batches to refill the weigh hopper. 4) There may be increased head room due to isolated feeder storage hopper. 5) Refill device may need to be oversized if time between batches is short. 4/03 Supersedes (4000-C26-1) 8/98 Page 4 of 8 Document: 6000-C24-1

5 COMPONENT COMPARISON, ADD WEIGH BATCHING and LOSS-IN-WEIGHT BATCHING BATCH TIME CHART AND FEED RATE CALCULATIONS VOLUMETRIC FEEDER/BATCHING WEIGH HOPPER TYPE LOSS-IN-WEIGHT FEEDER TYPE Bag unloading device (or other refill method) Refill method Dust collector Ingredient storage Ingredient storage Feeder hopper Storage isolation valve (optional) Volumetric feeder (one per ingredient) Remote actuated refill valve Loss-in-weight feeder (one per ingredient) Feeder hopper (weighed) Shut-off valve Shut-off valve Transfer conveyor (if required) Remote actuated valve Transfer conveyor (if required) To mixer 4/03 Supersedes (4000-C26-1) 8/98 Page 5 of 8 Document: 6000-C24-1

6 End of Previous Batch time between batches Start of New Batch dispensing batch to process End of New Batch ADD WEIGH batch make up time all feeders dispense their respective ingredients sequentially within this time period time for batch to be dispensed to the process time for refilling of feeder hopper (it can be refilled at any time) LIW time for refilling feeder weigh hopper for each ingredient time for feeders to dispense ingredients simultaneously to the process For Example: 3 ingredients A - Max. Batch Size - 50 lbs., B - Max. Batch Size - 90 lbs., C - Max. Batch Size lbs., Time - dispensing batch to process = 90 seconds Time - between batches = 90 seconds LIW Feeder (Max feed rate calculation formula) *1 = Max. Batch Size dispensing batch time x = lbs/hr. *1 Calculate dispensing batch time by subtracting 15 seconds for dribble feed. From the example: A Feed Rate B Feed Rate C Feed Rate = 50 x 3600 (90-15) = 2400 lbs/hr. = 90 x 3600 (90-15) = 4320 lbs/hr. = 120 x 3600 (90-15) = 5760 lbs/hr. 4/03 Supersedes (4000-C26-1) 8/98 Page 6 of 8 Document: 6000-C24-1

7 ADD WEIGH FEEDER The Maximum Feed Rate Calculation is based on each ingredient being fed for a portion of the time equivalent to its batch weight proportion of the total batch. On this basis, each feeder has the same feed rate calculated by total batch weight time between batches. However, the time between batches is modified to allow for dribble feed of each ingredient of 15 seconds each. In the example, the batch time available is 90 seconds - (3 x 15 seconds) = 45 seconds. Therefore the feed rate for each ingredient is: ( ) (90-45) x 3600 = 20,800 lbs./hr. This example shows that the feeder size for add weigh batching can be much larger than for loss in weight batching. NOTE: 1) FEED MECHANISM SELECTION IS MADE BY: - users experience based on successful existing operation; - ingredient supplier recommendation; - batching system supplier experience; - batching system supplier lab test. The feeder size is calculated based on the maximum feed rate in lbs/hr., bulk density and K fill for ingredient. 2) LOSS IN WEIGHT FEEDERS ARE IDEAL FOR LIQUID INGREDIENTS AS WELL AS DRY INGREDIENTS. 4/03 Supersedes (4000-C26-1) 8/98 Page 7 of 8 Document: 6000-C24-1

8 ACCURACY The accuracy of a batching system is based on: a) scale capacity *1 b) scale sensitivity *2 c) effect of installation conditions on scale sensitivity d) ability of feed mechanism to stop flow at batch completion (or control system allowance for free fall, etc.) e) loss of ingredient in being transferred to the process. Comment: 1. Typical in plant effects (c above) result in an overall weighing accuracy of ± 3 x scale capacity. This 3 provides a safety factor for determining actual achievable batching accuracy. Example: Scale Capacity lbs. Scale Sensitivity - 1/30,000 Safety Factor - 3 Feed Factor - 1/4 second of dribble feed rate - if dribble feed rate is 360 lbs./hr., then Feed Factor is lbs. expected Batch Accuracy: ± [(300 x 3 x 1 ) ] = ± If batch accuracy per ingredient is desired to be ±1%, then the smallest batch that can be accurately dispensed is 5.5 lbs. *1 Scale capacity is the maximum load that can be weighed by the scale. It includes dead load if the dead load is not mechanically counterbalanced. *2 Scale sensitivity is the smallest weight that can be accurately sensed by the scale at read out. It is determined by adding (and subtracting) known weights to (from) a scale, observing the read out and determining the smallest weight that can be added (and subtracted) over the full scale range to always produce the correct read out. Head Office: 6500 Kestrel Road Mississauga, Ontario Canada, L5T 1Z6 Telephone: Toll Free: Facsimile: (905) (888) (905) sales@brabenderti.com 4/03 Supersedes (4000-C26-1) 8/98 Page 8 of 8 Document: 6000-C24-1