Sedimentation

QSDsan: Quantitative Sustainable Design for sanitation and resource recovery systems

This module is developed by:

This module is under the University of Illinois/NCSA Open Source License. Please refer to https://github.com/QSD-Group/QSDsan/blob/main/LICENSE.txt for license details.

class qsdsan.unit_operations.static._sedimentation.Sedimentation(ID='', ins: Sequence[AbstractStream] | None = None, outs: Sequence[AbstractStream] | None = (), thermo=None, init_with='WasteStream', split=None, settled_frac=None, degraded_components=('OtherSS',), if_N2O_emission=False, **kwargs)

Sedimentation of wastes into liquid and solid phases based on Trimmer et al.

To enable life cycle assessment, the following impact items should be pre-constructed: Concrete, Steel.

Parameters:

  • ins (Iterable(stream)) – Waste for treatment.

  • outs (Iterable(stream)) – Liquid, settled solids, fugitive CH4, and fugitive N2O.

Examples

>>> from qsdsan.utils import create_example_sanitation_components
>>> cmps = create_example_sanitation_components()
>>> from qsdsan import System, WasteStream
>>> from qsdsan.unit_operations import Sedimentation
>>> ws = WasteStream('ws', H2O=1000, OtherSS=50, NH3=2, units='kg/hr')
>>> SD = Sedimentation('SD', ins=ws,
...                    outs=('settled', 'effluent', 'CH4', 'N2O'),
...                    split=0.5, decay_k_COD=3, max_CH4_emission=0.25)
>>> sys = System('sys', path=(SD,))
>>> sys.simulate()
>>> round(SD.outs[0].F_mass, 1)  # settled-solids mass flow, kg/hr
901.8

See bwaise systems for use in a complete sanitation system.

References

[1] Trimmer et al., Navigating Multidimensional Social–Ecological System Trade-Offs across Sanitation Alternatives in an Urban Informal Settlement. Environ. Sci. Technol. 2020, 54 (19), 12641–12653. https://doi.org/10.1021/acs.est.0c03296.

See also

qsdsan.process_models.Decay

property N_tank

[int] Number of sedimentation tanks, float will be converted to the smallest integer.

property column_per_side

[int] Number of columns per side of sedimentation tanks, float will be converted to the smallest integer.

property concrete_thickness

[float] Thickness of the concrete wall.

line: str = 'Sedimentation'

class-attribute Name denoting the type of Unit class. Defaults to the class name of the first child class

property roof_slope

[float] Slope of the tank roof, [°].

property roof_unit_mass

[float] Unit mass of the tank roof, [kg/m2].

run()

Run mass and energy balance. This method also runs specifications user defined specifications unless it is being run within a specification (to avoid infinite loops).

See also

_run, specifications, add_specification, add_bounded_numerical_specification

property tank_L_to_W

[float] Length-to-width ratio of the sedimentation tank.

property tank_V

[float] Volume of the sedimentation tank.

property tank_W_to_H

[float] Width-to-height ratio of the sedimentation tank.

property tau

[float] Residence time, [d].