Features¶
Code of bio-rtd library is fully covered with tests in bio_rtd_tests folder. For more info see Development.
Rtd model¶
Rtd model is composed of an inlet and a train of unit operations.
Inlet profiles¶
Available inlet profiles
Constant flow rate, constant concentration
bio_rtd.inlet.ConstantInletConstant flow rate, box-shaped concentration profile
bio_rtd.inlet.IntervalInletCustom flow rate, custom concentration profile
bio_rtd.inlet.CustomInlet
Unit operations¶
Unit operations are split in following groups:
Fully-continuous
bio_rtd.uo.fc_uo(accept and provide constant flow rate)Semi-continuous
bio_rtd.uo.sc_uo(accept constant and provide periodic flow rate)Surge tank
bio_rtd.uo.surge_tank(accept periodic and constant flow rate)Special
bio_rtd.uo.special_uo(the ones that do not fit in any of the above categories)
All unit operations can be instructed to discard parts of inlet or outlet process fluid stream in oder to optimize the start-up phase.
For common attributes among unit operations check bio_rtd.core.UnitOperation class.
For complete parameter set of individual
unit operation, check its API by clicking the class name.
Here are listed key features of unit operations:
Instant dilution of the process fluid stream.
bio_rtd.uo.fc_uo.Concentration
Instant concentration of the process fluid stream.
One can specify retained species and losses during concentration step.
bio_rtd.uo.fc_uo.BufferExchange
Instant inline buffer exchange.
One can specify retained species, losses and efficiency.
Propagation of the process fluid stream through a fixed unit operation (most common use case).
A probability distribution function is specified to describe the propagation dynamics.
Offers setting equilibration and wash buffer composition (for more parameters check the class link).
bio_rtd.uo.fc_uo.FlowThroughWithSwitching
Extension of the
bio_rtd.uo.fc_uo.FlowThrough.Allows switching unit operations during run (e.g. for alternating flow-through chromatography).
Alternating column chromatography (without recycling of the overloaded material).
Describing binding dynamics via
bio_rtd.core.BreakthroughProfile.Option to specify load duration based on breakthrough material.
Material in elution peak is homogenized. Various peak cut methods are available.
Periodic counter-current chromatography.
Extension of
bio_rtd.uo.sc_uo.ACC.Option to recycle breakthrough material during load and/or wash step.
bio_rtd.uo.sc_uo.PCCWithWashDesorption
Extension of
bio_rtd.uo.sc_uo.PCC.Option to simulate desorption of captured material during wash step.
Ideal CSTR.
Offers specifying initial fill level.
Size can be determined based on specified ‘safety margin’, e.g. 10 %
Unit operation that combines several unit operations and presents them as one.
Some unit operations can be described with a set of simpler unit operation, but we might want to have them appear (e.g. in plots) as one. Typical use-case would be describing filtration or diafiltration step with a combination of Concentration, Dilution and/or FlowThrough unit operations. In such case, one can use ComboUO as a container.
Probability distribution functions¶
Available pdf peak shapes:
Gaussian:
bio_rtd.peak_shape.gaussian()Exponentially modified Gaussian:
bio_rtd.peak_shape.emg()Skewed normal:
bio_rtd.peak_shape.skewed_normal()N tanks in series (N = 1 for exponential decay):
bio_rtd.peak_shape.tanks_in_series()
Available PDF classes (wrappers around pdf peak shapes):
Fixed dispersion:
sigma = (void_volume * dispersion_index) ** 0.5
Fixed relative width:
sigma = void_volume * relative_width