SCALE-UP

1
SCALE-UP

• Definition
• Act of using results obtained from laboratory
  studies for designing a prototype and a pilot
  plant processconstruction a pilot plant and
  using pilot plant data for designing and
  constructing a full scale plant or modifying an
  existing plant

2
Problems in Scale up an Food Production Processes

• Fundamental knowledge of chemical and physical
  interactions among complex ingredients is either
  scarce or non-existent
• There is usually a lack of data of physical
  properties for complex food formulations
  (specific heat capacities, thermal
  conductivities, phase relationship, rheology, etc)

3
Steps in Scale-Up

• Define product economics based on projected
  market size and competitive selling and provide
  guidance for allowable manufacturing costs
• Conduct laboratory studies and scale-up planning
  at the same time
• Define key rate-controlling steps in the proposed
  process
• Conduct preliminary larger-than-laboratory
  studies with equipment to be used in
  rate-controlling step to aid in plant design
• Design and construct a pilot plant including
  provisions for process and environmental
  controls, cleaning and sanitizing systems,
  packaging and waste handling systems, and meeting
  regulatory agency requirements
• Evaluate pilot plant results (product and
  process) including process economics to make any
  corrections and a decision on whether or not to
  proceed with a full scale plant development

4
Why conduct Pilot Plant Studies?

• A pilot plant allows investigation of a product
  and process on an intermediate scale before large
  amounts of money are committed to full-scale
  production
• It is usually not possible to predict the effects
  of a many-fold increase in scale
• It is not possible to design a large complex food
  processing plant from laboratory data alone with
  any degree of success

5
A pilot plant can be used for

• Evaluating the results of laboratory studies and
  making product and process corrections and
  improvements
• Producing small quantities of product for
  sensory, chemical, microbiological evaluations,
  limited market testing or furnishing samples to
  potential customers, shelf-live and storage
  stability studies
• Determining possible salable by-products or waste
  stream requiring treatment before discharge
• Providing data that can be used in making a
  decision on whether or not to proceed to a
  full-scale production process and in the case of
  a positive decision, designing and constructing a
  full-size plant or modifying an existing plant

6
Considerations in pilot plant development

• Kind and size depends on goals evaluating
  product and process producing samples of product
  for evaluation market testing or furnishing to
  potential customers
• Location near RD facility? At an existing
  plant? Close liaison between RD and pilot plant
  staff is essential
• Labor requirements and costs engineering staff,
  skilled operations and maintenance staff- pilot
  plant costs may exceed those of usual plant
  production costs. The pilot plant may be used
  for training personnel for a full- scale plant

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SIMILITUDES IN SCALE-UP

• 4 DIMENSIONS FORCE, MASS, DISTANCE AND LENGTH
• LACK OF DIFFERENTIAL EQUATIONS DURING PILOT PLANT
  TRIALS LIMITS USEFULLNESS
• DYNAMIC EQUALITY BETWEEN DIMENSIONLESS NUMBERS
• NOT ALWAYS POSSIBLE TO ACHIED DYNAMIC SIMILARITY
  BETWEEN SCALES. DIFFERENCES SUCH AS VORTEXING AND
  SURFACE TENSION CAN EFFECT RESULTS.
• CHEMICAL- OFTEN IMPOSSIBLE TO DETERMININE RATE
  LIMITING REACTIONS IN FOOD SYSTEM
• DIFFUSION AND TEMPERATURE CAN BE IMPORTANT AND
  NOT ALWAYS COMPARABLE AT DIFFERENT SCALES

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EXAMPLE YEAST FERMENTATON

• DEFINE DESIRED RESULTS
• PRODUCTION SIZE
• FERMENTER SIZE
• RAW MATERIALS
• SOLIDES AFTER CENTRIFUGING
• LAB SCALE DATA AVAILABLE
• EVALUATION INFORMATION AT HAND
• SCALE UP REQUIRED FOR
• HOLDING TANKS
• FERMENTER FOR SEED INOCULUM
• 4 SCALES TO FULL PRODUCTION OF FERMENTERS,
  CENTRIGUGES, FILTRATION AND DRYING

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• Yeast Scale-up Example
• Production goal 7200 kg (dw)/14 hr. run
• Fermenter-150 m3 (120 m3 working volume),
• 14 h run., fed batch operation
• Solids after centrifugation, filter pressing
  and
• drying, 96

10

• Yeast Scale-up Example
• Production goal 7200 kg (dw)/14 h run
• Fermenter-150 m3 (120 m3 working volume),
• 14 h run., fed batch operation
• Solids after centrifugation, filter pressing
  and
• drying, 96

11
Yeast Scale-up Example

• Laboratory Scale Data
• Fermenter, 15 L (12 L working volume).
• H/D 21, t 30C., pH 4.5, heat output 3-4.4
• kcal/ g yeast solids, dissolved O2 7 ppm.
• Specific growth rate, 0.2/h, yield 0.55kg/kg
• fermentable sugars, cell conc. 0.65 g (dw)/L
• Pilot plant fermenter, 150 L