RUFAS.routines.manure.constants_and_units.gas_emission_constants module

class RUFAS.routines.manure.constants_and_units.gas_emission_constants.GasEmissionConstants

Bases: object

Constants used in gas emission calculations.

HOUR_TO_DAY_CONVERSION_FACTOR = 24

The conversion factor from hours to days.

DEGRADABLE_VOLATILE_SOLIDS_RATE_CORRECTING_FACTOR: float = 1.0

Rate correcting factor for degradable volatile solids, used in calculation of slurry storage methane emission (unitless).

NON_DEGRADABLE_VOLATILE_SOLIDS_RATE_CORRECTING_FACTOR: float = 0.01

Rate correcting factor for non-degradable volatile solids, used in calculation of slurry storage methane emission (unitless).

NATURAL_LOG_ARRHENIUS_CONSTANT: float = 31.2

Natural log of the Arrhenius constant (g \(CH_4\)/kg manure VS/h).

ACTIVATION_ENERGY: float = 81000.0

Activation energy (joules per mole, J/mol). The activation energy is the minimum energy that must be available to molecules for a reaction to occur.

GAS_CONSTANT: float = 8.314

The ideal gas constant (J/mol \(\cdot\) K).

ACHIEVABLE_METHANE_EMISSION: float = 0.24

Achievable emission of methane (\(CH_4\)) from dairy manure (\(m^3 CH_4\)/kg VS).

METHANE_CONVERSION_FACTOR: float = 0.79

Methane conversion factor (unitless).

FRACTION_OF_HANDLED_MANURE: float = 0.9

Fraction of manure handled by the manure management system (unitless).

METHANE_FACTOR: float = 0.67

Unit conversion factor for methane from \(m^3\) to kg (unitless).

METHANE_ENERGY_DENSITY: float = 55.0

Methane energy density (megajoules per kg, MJ/kg). This is the amount of energy stored per unit mass of methane.

METHANE_TO_METHANE_CARBON_DIOXIDE_RATIO: float = 9.25

The mass conversion factor from methane to methane and carbon dioxide emitted from stored manure, based on a molar ratio of 1:3 (methane : carbon dioxide).

AD_METHANE_DENSITY: float = 0.629

Unit conversion factor for methane generated from anaerobic digestion at 1 atm of pressure and 37.5C (kg/\(m^3\)).

AD_CARBON_DIOXIDE_DENSITY: float = 1.716

Unit conversion factor for carbon dioxide generated from anaerobic digestion at 1 atm of pressure and 37.5C (kg/\(m^3\)).

AD_CARBON_DIOXIDE_TO_METHANE_RATIO: float = 0.6666666666666666

The volumetric ratio of carbon dioxide to methane generated during anaerobic digestion (\(m^3 CO_2\) / \(m^3 CH_4\)).

MCF_CONSTANT_A: float = 0.0625

Parameter estimate (unitless) of a regression using IPCC data (2006) used in the Methane Conversion Factor (MCF) calculation. The coefficient scales the ambient barn temperature.

MCF_CONSTANT_B: float = 0.25

Parameter estimate (unitless) of a regression using IPCC data (2006) used in the Methane Conversion Factor (MCF) calculation. The coefficient is a constant offset.

MCF_LOWER_BOUND_TEMPERATURE: float = 15.0

The lower bound temperature for determining MCF for windrow composting.

MCF_UPPER_BOUND_TEMPERATURE: float = 25.0

The lower bound temperature for determining MCF for windrow composting.

MCF_COMPOSTING_STATIC_PILE: float = 0.005

The MCF for static pile composting.

MCF_COMPOSTING_WINDROW_LOW: float = 0.005

The MCF for windrow composting when the air temperature is below the lower bound temperature.

MCF_COMPOSTING_WINDROW_MEDIUM: float = 0.01

The MCF for windrow composting when the air temperature is between the lower and upper bound temperature.

MCF_COMPOSTING_WINDROW_HIGH: float = 0.015

The MCF for windrow composting when the air temperature is above the upper bound temperature.

POTENTIAL_METHANE_YIELD_OF_MANURE: float = 0.48

Potential methane yield of manure, (kg \(CH_4\)/kg VS). This represents the potential amount of methane that can be produced per kilogram of volatile solids (VS) in manure. Default is set to 0.48.

DEFAULT_SLURRY_STORAGE_TEMPERATURE: float = 15.0

Default slurry storage temperature (\(^{\circ}C\)). Default is set to 15.0.

DEFAULT_VOLATILE_SOLIDS_FRACTION: float = 0.68

Default volatile solids fraction, (unitless, [0, 1]). This is the fraction of total solids that are volatile Default is set to 0.68.

HOUSING_HSC = 260.0

Default housing specific constant (s/m). This constant may be used in calculations related to the housing conditions for animals. Default is set to 260.0 s/m.

DEFAULT_PH_FOR_HOUSING_AMMONIA: float = 7.7

Default pH for housing ammonia (unitless). Default is set to 7.7.

DEFAULT_PH_FOR_STORAGE_AMMONIA: float = 7.5

Default pH for storage ammonia (unitless). Default is set to 7.5.

OXYGEN_HALF_SATURATION_CONSTANT: float = 0.02

The half saturation constant of Oxygen gas (O2)

DEFAULT_CARBON_AVAILABLE_IN_BEDDING: float = 0.35

Default proportion of carbon available in bedding, (unitless, [0, 1]). Default is set to 0.35.

GENERAL_LOWER_BOUND_TEMPERATURE: float = -40.0

General temperature lower bound (\(^{\circ}C\)). Default is set to -40.0.

GENERAL_UPPER_BOUND_TEMPERATURE: float = 60.0

General temperature upper bound (\(^{\circ}C\)). Default is set to 60.0.

SOLID_AND_SEMI_SOLID_MANURE_HSC: float = 10.0

Housing specific constant for solid and semi-solid manure (s/m).

SLURRY_MANURE_HSC: float = 19.0

Housing specific constant for slurry manure (s/m).

STORAGE_HSC = 4.1

Housing specific constant for manure storage (s/m).

SOLID_MANURE_THRESHOLD = 0.08

Dry matter threshold for classifying solid and semi-solid manure (unitless).

SLURRY_MANURE_THRESHOLD = 0.05

Dry matter threshold for classifying slurry manure (unitless).

DEFAULT_STORAGE_AREA_PER_ANIMAL: float = 1.0

Default storage area per animal (\(m^2\)). Default is set to 1.0.

AMMONIA_EMISSION_COEFFICIENT_WITH_TILLED_BEDDING: float = 0.5

Ammonia emission coefficient used for calculating nitrogen loss in a compost bedded pack barn when the bedding is tilled (unitless).

AMMONIA_EMISSION_COEFFICIENT_WITH_UNTILLED_BEDDING: float = 0.25

Ammonia emission coefficient used for calculating nitrogen loss in a compost bedded pack barn when the bedding is not tilled (unitless).

LEACHING_COEFFICIENT: float = 0.035

Leaching coefficient used in the calculation of nitrogen loss in a compost bedded pack barn (unitless).

NITROUS_OXIDE_COEFFICIENT_WITH_TILLED_BEDDING: float = 0.07

Nitrous oxide coefficient used for calculating nitrogen loss in a compost bedded pack barn when the bedding is tilled (unitless).

NITROUS_OXIDE_COEFFICIENT_WITH_UNTILLED_BEDDING: float = 0.01

Nitrous oxide coefficient used for calculating nitrogen loss in a compost bedded pack barn when the bedding is not tilled (unitless).

DEFAULT_CARBON_FRACTION_AVAILABLE_IN_BEDDING: float = 0.35

Default proportion of carbon available in bedding, (unitless, [0, 1]). Default is set to 0.35.

NITROUS_OXIDE_COEFFICIENT_IN_OPEN_LOTS: float = 0.02

Nitrous oxide coefficient used for calculating nitrogen loss in an open lot (unitless).

AMMONIA_EMISSION_COEFFICIENT_IN_OPEN_LOTS: float = 0.36

Ammonia emission coefficient used for calculating nitrogen loss in an open lot (unitless).

DEFAULT_EFFECTIVENESS_OF_MICROBIAL_DECOMPOSITION_RATE: float = 0.00273

The default effectiveness of microbial decomposition rate.

DEFAULT_COMPOSTING_DECOMPOSITION_TEMPERATURE: float = 60.0

The default decomposition temperature for composting.

DEFAULT_FIRST_ORDER_DECAYING_COEFFICIENT: float = 0.1

The default first order decaying coefficient.

DEFAULT_MOLE_FRACTION_OF_OXYGEN: float = 0.15

The default mole fraction of Oxygen.

DEFAULT_AMBIENT_AIR_MOLE_FRACTION_OF_OXYGEN: float = 0.21

The default ambient air mole fraction of Oxygen.

DEFAULT_EFFECT_OF_MOISTURE_ON_MICROBIAL_DECOMPOSITION: float = 0.65

The default effect of moisture on microbial decomposition.

FRACTION_NITROGEN_LOST_TO_AMMONIA_EMISSION: Dict[CompostingType, float] = {CompostingType.INTENSIVE_WINDROW: 0.5, CompostingType.PASSIVE_WINDROW: 0.45, CompostingType.STATIC_PILE: 0.5}

FRACTION_NITROGEN_LOST_TO_LEACHING: Dict[CompostingType, float] = {CompostingType.INTENSIVE_WINDROW: 0.06, CompostingType.PASSIVE_WINDROW: 0.04, CompostingType.STATIC_PILE: 0.06}

FRACTION_NITROGEN_LOST_TO_DIRECT_N2O_EMISSION: Dict[CompostingType, float] = {CompostingType.INTENSIVE_WINDROW: 0.06, CompostingType.PASSIVE_WINDROW: 0.04, CompostingType.STATIC_PILE: 0.06}

NITROUS_OXIDE_EMISSION_FACTOR_KG_NITROUS_OXIDE_N_PER_KG_MANURE_N: Dict[ManureTreatmentType, Dict[str, float]] = {ManureTreatmentType.ANAEROBIC_DIGESTION: {'N/A': 0.0006}, ManureTreatmentType.ANAEROBIC_LAGOON: {'cover': 0.005, 'cover and flare': 0.005, 'crust': 0.005, 'no cover': 0.0}, ManureTreatmentType.SLURRY_STORAGE_OUTDOOR: {'cover': 0.005, 'cover and flare': 0.005, 'crust': 0.005, 'no cover': 0.0}, ManureTreatmentType.SLURRY_STORAGE_UNDERFLOOR: {'cover': 0.005, 'cover and flare': 0.005, 'crust': 0.005, 'no cover': 0.0}}

Nitrous oxide emission factor (kg Nitrous Oxide N/kg manure N) for different manure treatment and storage systems.