The first stage of design assumes: budget is approved, marketing research is complete, product can be made at a price below that which it can be sold, research and development is complete (Patent life).
The following simple equation can be used to estimate the annual production required (accounting for likely downstream processing losses of product):
Annual Production = [Cp] Vnvb
where [Cp] = product concentration
V = harvested volume
nv = number of vessels
b = number of batches (b = 365 E / t)
t = time (incl. turnaround time)
E = operational efficiency (~ 0.9)
Issues to consider include plant closures, e.g. holidays and maintenance,plant problems, e.g. plant failure, batch failure, and process problems e.g. slow batches.
If we know the annual production requirements, we can estimate the product of (V, nv) which could be either one very large vessel or many small ones or any combination in between. Factors influencing this decision include:
1. Capital cost - capital cost/m3 goes down as scale goes up
2. Instrumentation costs
3. Downstream processing
4. Batch reliability
5. Number of seed stages