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Methodological tool

“Tool to determine the mass flow of a greenhouse gas in a gaseous stream”

(Version 01)

I. DEFINITIONS, SCOPE, APPLICABILITY AND PARAMETERS

Definitions
For the purpose of this tool, the following definitions apply:
Dry gas. The dry gas is a mixture of gaseous components (except H2O) that are present in a gaseous
stream. The gaseous stream may contain different fractions of N2, CO2, O2, CO, H2, CH4, N2O, NO, NO2,
SO2, SF6 and PFCs. Other gases may be present (e.g., hydrocarbons) provided their total concentration
represents less than 1% (v/v) of the total.
Absolute humidity or mass fraction of water in dry basis. The absolute humidity of a gas is the ratio
between the mass of H2O (vapor phase) in the gas and the mass of the dry gas.
Saturation (absolute) humidity. The saturation (absolute) humidity is the maximum amount of H2O
(vapor phase) that the gas can contain at a given temperature and pressure, expressed as mass of H2O per
mass of the dry gas.
Moisture content. The moisture content of a gas is the H2O concentration in mass of H2O (vapor phase)
per volume of dry gas at normal conditions (NPT), expressed in mg H2O/m3 dry gas.
Relative humidity. The relative humidity of a gas is the ratio between the partial pressure of H2O in the
gas and the saturation pressure at a given temperature.
“Wet basis” means that a parameter accounts for the H2O present in the gas.
“Dry basis” means that a parameter does not account for the H2O present in the gas.
“Normal conditions” are defined as 0oC (273.15 K, 32oF) and 1 atm (101.325 kN/m2, 101.325 kPa, 14.69
psia, 29.92 in Hg, 760 torr).

Scope and applicability

This tool provides procedures to determine the mass flow of a greenhouse gas in a gaseous stream. The
tool can be used to determine the mass flow of the following gases: CO2, CH4, N2O, SF6 and/or PFCs.
The mass flow of a particular greenhouse gas is calculated based on measurements of (a) the total volume
or mass flow of the gas stream and (b) the volumetric fraction of the gas in the gas stream. The volume
flow, mass flow and volumetric fraction may be measured on a dry basis or wet basis. The tool covers
most of the possible measurement combinations, providing eight different options to determine the mass
flow of a particular gas (options A to H below). Typical applications of this tool are methodologies where
the flow and composition of residual or flared gases or exhaust gases are measured for the determination
of baseline or project emissions.
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When no measurement of the moisture content in the gaseous stream is performed, a simplified
conservative approach is used by assuming that the gas is saturated with H2O or that no H2O is in the gas,
whichever is more conservative in the context of the underlying methodology.1
This tool is applicable under the followings conditions:

• The tool is only applicable to gaseous streams consisting of at least 99% or a larger volumetric
fraction of the following gases: N2, CO2, O2, CO, H2, CH4, N2O, NO, NO2, SO2, SF6 and PFCs and
H2O in vapor phase.2 Other gases may be present (e.g., hydrocarbons) provided their total
concentration represents less than 1% (v/v) of the total;3
• The absolute pressure of the gas must be below 10 atm or 1.013 MPa.4
The underlying methodology should specify to which gaseous stream the tool should be applied, for which
greenhouse gases the mass flow should be determined, and in which time intervals the mass flow of the
gaseous stream should be measured.

Parameters
This tool provides procedures to determine the following parameter:

Parameter SI Unit Description

Fi,t kg / h Mass flow of greenhouse gas i (CO2, CH4, N2O, SF6 or a PFC) in the
gaseous stream in time interval t

1
For example, in the case that (1) the greenhouse gas in the gaseous stream is emitted as project emission source, (2)
the mass or volume flow of the gas stream is measured on a wet basis and (3) the volumetric fraction of the
greenhouse gas is measured on a dry basis, it is a conservative simplification to assume that no H2O is present in
the gas stream.
2
This condition is required because it is assumed in the calculations that the gas stream behaves as an ideal binary
mixture of water vapor and an ideal gas. If the gaseous stream contains larger fractions of other gases, such as
hydrocarbons other than methane or HFCs, the gas cannot be considered to be an ideal gas mixture.
3
For the cases of landfill gas and exhaust gases from thermal oxidation using natural gas, it will be assumed that this
applicability condition is fulfilled.
4
Moderate pressures will assure that gases behave as ideal gases and the tool applies.
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II. PROCEDURE
The mass flow of a greenhouse gas i in a gaseous stream (Fi,t) is determined through measurement of the
volume or mass flow of the gaseous stream and measurement of the volumetric fraction of the gas.
Measurements may occur on a dry basis or wet basis. The following options for measurement may be
used:

Option Volume flow of Mass flow of Volumetric

gaseous stream gaseous stream fraction
A dry basis - dry basis
B dry basis - wet basis
C wet basis - dry basis
D wet basis - wet basis
E - dry basis dry basis
F - dry basis wet basis
G - wet basis dry basis
H - wet basis wet basis

Project participants should document in the CDM-PDD which option is applied. Fi,t should be calculated
following the steps/guidance described for each option below.

Option A and B
Under these conditions, since the gaseous stream is assumed to be dry at the measuring point (flow
measurement is not possible in dry basis for a wet stream) there will be no difference in the readings for
volumetric fraction in wet basis analyzers and dry basis analyzers and both types can be used indistinctly.
The gas will be considered to be dry provided its absolute humidity (as determined in option C) is shown
to be less or equal to 10-2 kg H2O/kg dry gas or the moisture content is less or equal to 0.0129 kg H2O/m3
dry gas. If the absolute humidity or moisture content are found to be higher than this threshold value, the
gas can not be assumed as being dry and project proponents should adopt option C or D.
The mass flow of greenhouse gas i (Fi,t) is determined as follows:

Fi,t = Vt,db × v i,t,db × ρ i,t (1)

with

Pt * MM i
ρ i,t = (2)
R u * Tt
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Where:
Fi,t = Mass flow of greenhouse gas i in the gaseous stream in time interval t (kg gas/h)
Vt,db = Volumetric flow of the gaseous stream in actual conditions (Pt, Tt) in time interval t on
a dry basis (m³ dry gas/h)
ρi,t = Density of greenhouse gas i in the gaseous stream in actual conditions (Pt, Tt) in time
interval t (kg gas i/m³ dry gas)
vi,t,db = Volumetric fraction of greenhouse gas i in the gaseous stream in a time interval t on a
dry or wet basis (m³ gas i/m³ dry gas)
Pt = Absolute pressure of the gaseous stream in time interval t (Pa)
MMi = Molecular mass of greenhouse gas i (kg/kmol)
Ru = Universal ideal gases constant (8314 Pa.m3/kmol.K)
Tt = Temperature of the gaseous stream in time interval t (K)

Option C
The mass flow of greenhouse gas i (Fi,t) is determined using equations (1) and (2). The volumetric flow of
the gaseous stream in time interval t on a dry basis (Vt,db) is determined by converting the volumetric flow
from wet basis to dry basis as follows:

v i, t,db = v i, t, wb ∗ (1 + v H2O, t,db ) (3)

Where:
Vt,db = Volumetric flow of the gaseous stream in time interval t on a dry basis (m³ dry gas/h)
Vt,wb = Volumetric flow of the gaseous stream in time interval t on a wet basis (m³ wet gas/h)
vH2O,t,db = Volumetric fraction of H2O in the gaseous stream in time interval t on a dry basis
(m³ H2O/m³ dry gas)

The volumetric fraction of H2O in time interval t on a dry basis (vH2O,t,db) should be estimated as per the
procedure provided bellow.

m H2O, t,db * MM t,db

ν H2O, t,db = (4)
MM H2O

Where:
vH2O,t,db = Volumetric fraction of H2O in the gaseous stream in time interval t on a dry basis
(m³ H2O / m³ dry gas)
mH2O,t,db = Mass fraction of H2O in the gaseous stream in time interval t on a dry basis
(kg H2O / kg dry gas)
MMt,db = Molecular mass of the gaseous stream in time interval t on a dry basis
(kg dry gas / kmol dry gas)
MMH2O = Molecular mass of H2O (kg H2O/kmol H2O)

And MMt,db is determined as follows:

MM t,db = ∑ (ν k, t,db * MM k ) (5)

k
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Where:
MM t ,db = Molecular mass of the gaseous stream in time interval t on a dry basis
(kg dry gas / kmol dry gas)
ν k ,t ,db = Volumetric fraction of gas k in the gaseous stream in time interval t on a dry basis
(m³ gas k / m³ dry gas)
MM k = Molecular mass of gas k (kg / kmol)
k = All gases contained in the gaseous stream (e.g. N2, CO2, O2, CO, H2, CH4, N2O, NO,
NO2, SO2, SF6 and PFCs )

The determination of the molecular mass of the gaseous stream depends on the measurement of the
volumetric fraction of every compound present in the gaseous stream in dry basis. The following
simplification is acceptable only for molecular mass determination purposes, unless differently specified
in the underlying methodology:

• In case of a gaseous stream containing greenhouse gases including CO2, the greenhouse gases
must be monitored according to the provisions provided in the monitoring section. The difference
to 100% could be considered as pure nitrogen.
The mass fraction of water in time interval t on a dry basis (mH2O,t,db) can be determined using one of the
following two options. Project participants should document in the CDM-PDD which option they apply.

Option 1: Measurement of the moisture content

This option provides a procedure to determine the mass fraction of H2O in the gaseous stream from
measurements of the moisture content of the gas. The moisture content in the gaseous stream should be
measured according to the USEPA CF42 method 4 and then converted to the mass fraction of H2O in the
gaseous stream in time interval t on a dry basis (mH2O,t,db) as follows:

C H2O, t,db, n
m H2O, t,db = (6)
10 6 * ρ t,db, n

Where:
mH2O,t,db = Mass fraction of H2O in the gaseous stream in time interval t on a dry basis
(kg H2O / kg dry gas)
CH2O,t,db,n = Moisture content of the gaseous stream, according to the USEPA CF42 method 4, at
normal conditions in time interval t (mg H2O/m3 dry gas)
ρt,db,n = Density of the gaseous stream in time interval t on a dry basis at normal conditions
(kg dry gas / m3 dry gas)

The moisture content at normal conditions is determined as follows:

10 6 * M H2O, t
C H2O, t,db, n = (7)
Vt,db, n
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Where:
CH2O,t,db,n = Moisture content of the gaseous stream, according to the USEPA CF42 method 4, at
normal conditions in a time interval t (mg H2O/ m3 dry gas)
MH2O,t = Mass flow of H2O in the gaseous stream in time interval t (kg H2O / h)
Vt,db,n = Volumetric flow of the gaseous stream in a time interval t at normal conditions on a
dry basis (m3 dry gas / h)
The density of the gaseous stream on a dry basis at normal conditions (ρt,db,n) is determined as follows:

Pn * MM t,db
ρ t,db,n = (8)
R u * Tn

Where:
ρt,db,n = Density of the gaseous stream in time interval t on a dry basis at normal conditions
(kg dry gas / m3 dry gas)
Pn = Absolute pressure at normal conditions (101325 Pa)
Tn = Temperature at normal conditions (273.15 K)
MMt,db = Molecular mass of the gaseous stream in a time interval t on a dry basis
(kg dry gas / kmol dry gas)
Ru = Universal ideal gases constant (8314 Pa.m3/kmol.K)

And MMt,db is estimated as per equation (5).

The following equation should be used to convert the volumetric flow of the gaseous stream from actual
conditions to normal conditions of temperature and pressure:

Vt,db, n = Vt,db * (273.15/Tt ) * (Pt /101,325) (9)

Where:
Pt = Absolute pressure of the gaseous stream in time interval t (Pa)
Tt = Temperature of the gaseous stream in time interval t (K)
Vt,db,n = Volumetric flow of the gaseous stream in a time interval t at normal conditions on a
dry basis (m3 dry gas/h)
Vt,db = Volumetric flow of the gaseous stream in time interval t at actual conditions on a dry
basis (m³/h)

Option 2: Simplified calculation without any measurements of the moisture content

This option does not require measuring the moisture content of the gas but provides a simple and
conservative approach to determine the absolute humidity of the gaseous stream. It is assumed that the
gas is saturated with H2O or that no H2O is in the gas, whichever is more conservative in the context of the
underlying methodology.
If it is conservative to assume that no H2O in vapor phase is in the gaseous stream, assume mH2O,t,db = 0. If
it is conservative to assume that the gaseous stream is saturated with H2O, determine mH2O,t,db as follows:
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p H2O,t,Sat * MM H2O
m H2O,t,db,Sat =
(Pt − p H2O,t, Sat ) * MM t,db
(10)
Where:
mH2O,t,db,sat = Saturation absolute humidity in time interval t on a dry basis (kg H2O/kg dry gas)
pH20,t,Sat = Saturation pressure of H2O at temperature Tt (Pa)
Tt = Temperature of the gaseous stream in time interval t (K)
Pt = Absolute pressure of the gaseous stream in time interval t (Pa)
MMH2O = Molecular mass of H2O (kg H2O/kmol H2O)
MMt,db = Molecular mass of the gaseous stream in a time interval t on a dry basis
(kg dry gas / kmol dry gas)

Option D
The mass flow of greenhouse gas i (Fi,t) is determined as follows:
Fi, t = Vt, wb,n × v i, t, wb,n × ρ i, n (11)

with
Pn * MM i
ρ i, n = (12)
R u * Tn

Where:
Vt,wb = Volumetric flow of the gaseous stream in time interval t on a wet basis (m³ wet gas/h)
vi,t,wb,n = Volumetric fraction of greenhouse gas i in the gaseous stream in time interval t on a
wet basis (m³ gas i/m³ wet gas)
ρi,n = Density of greenhouse gas i in the gaseous stream at normal conditions (kg gas i/m³
dry gas)
Pn = Absolute pressure at normal conditions (101325 Pa)
Tn = Temperature at normal conditions (273.15 K)
MMi = Molecular mass of greenhouse gas i (kg/kmol)
Ru = Universal ideal gases constant (8314 Pa.m3/kmol.K)

The following equation should be used to convert the volumetric flow of the gaseous stream from actual
conditions to normal conditions of temperature and pressure:

Vt, wb,n = Vt, wb * [(273.15/Tt ) * (Pt /101,325)] (13)

Where:
Pt = Pressure of the gaseous stream in time interval t (Pa)
Tt = Temperature of the gaseous stream in time interval t (K)
Vt,wb,n = Volumetric flow of the gaseous stream in a time interval t at normal conditions on a
wet basis (m3 wet gas / h)
Vt,wb = Volumetric flow of the gaseous stream in time interval t at actual conditions on a wet
basis (m³ wet gas/h)
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Option E and F

Under these conditions, since the gaseous stream is assumed to be dry at the measuring point (flow
measurement is not possible in dry basis for a wet stream) there will be no difference in the readings for
volumetric fraction in wet basis analyzers and dry basis analyzers and both types can be used indistinctly.
The gas will be considered to be dry provided its absolute humidity (as determined in option C) is shown
to be less or equal to 10-2 kg H2O/kg dry gas or the moisture content is less or equal to 0.0129 kg H2O/m3
dry gas. If the absolute humidity or moisture content are found to be higher than this threshold value, the
gas can not be assumed as being dry and project proponents should adopt option G or H.
The mass flow of greenhouse gas i (Fi,t) is determined using equations (1) and (2). The volumetric flow of
the gaseous stream in time interval t on a dry basis at actual conditions (Vt,db) is determined by converting
the mass flow of the gaseous stream to a volumetric flow as follows:

Vt,db = M t,db /ρ t,db (14)

Where:
Vt,db = Volumetric flow of the gaseous stream in a time interval t at actual conditions on a dry
basis (m3 dry gas/h)
Mt,db = Mass flow of the gaseous stream in time interval t on a dry basis (kg/h)
ρt,db = Density of the gaseous stream in time interval t on a dry basis at actual conditions
(kg dry gas / m3 dry gas)
ρt,db should be determined as per equation (2).
Option G
The mass flow of greenhouse gas i (Fi,t) is determined using equations (1) and (2). The volumetric flow of
the gaseous stream in time interval t on a dry basis (Vt,db) is determined in two steps. First the mass flow
of the gaseous stream in time interval t on a wet basis (Mt,wb) is converted from wet basis to dry basis as
follows:

M t,db = M t, wb / (1 + m H2O,t,db ) (15)

Where:
Mt,db = Mass flow of the gaseous stream in time interval t on a dry basis (kg/h)
Mt,wb = Mass flow of the gaseous stream in time interval t on a wet basis (kg/h)
mH2O,t,db = Mass fraction of H2O in the gaseous stream in a time interval t on a dry basis
(kg H2O / kg dry gas)
Then, the mass flow of the gaseous stream in time interval t on a dry basis (Mt,db) is converted to the
volumetric flow of the gaseous stream in time interval t on a dry basis (Vt,db) following the procedure in
Option E.
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Option H
The mass flow of greenhouse gas i (Fi,t) is determined as follows:

Fi,t = Vt,wb,n × v i,t,wb × ρ i,n (16)

with

Vt, wb,n = M t, wb /ρ t, wb,n (17)

and

Pn * MM t, wb
ρ t, wb,n = (18)
R u * Tn
Where:
Fi,t = Mass flow of greenhouse gas i in the gaseous stream in time interval t (kg gas/h)
Vt,wb,n = Volumetric flow of the gaseous stream in time interval t at normal conditions on a wet
basis (m3 dry gas/h)
vi,t,wb = Volumetric fraction of greenhouse gas i in the gaseous stream in time interval t on a
wet basis (m³ gas i/m³ wet gas)
Mt,wb = Mass flow of the gaseous stream in time interval t on a wet basis (kg/h)
ρt,wb,n = Density of the gaseous stream in a time interval t at normal conditions on a wet basis
(kg wet gas/m3 wet gas)
Pn = Absolute pressure at normal conditions (101325 Pa)
Tn = Temperature at normal conditions (273.15 K)

MMt,wb = Molecular mass of the gaseous stream in a time interval t on a wet basis
(kg wet gas / kmol wet gas)
Ru = Universal ideal gases constant (8314 Pa.m3/kmol.K)
ρi,n = Density of greenhouse gas i in the gaseous stream at normal conditions (kg gas i/m³
dry gas)
ρi,n is determined as per equation (13) above.
And,

MM t ,wb = ∑ (ν k ,t ,wb * MM k ) (19)

k
Where:
MM t ,wb = Molecular mass of the gaseous stream in time interval t on a wet basis
(kg dry gas / kmol wet gas)
ν k ,t ,wb = Volumetric fraction of gas k in the gaseous stream in time interval t on a wet basis (m³
gas k/m³ wet gas)
MM k = Molecular mass of gas k (kg / kmol)
k = Gas in the gaseous stream (e.g. N2, CO2, O2, CO, H2, CH4, N2O, NO, NO2, SO2, SF6 and
PFCs and H2O in vapor phase)
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Data and parameters not monitored

Data / Parameter: Ru
Data unit: Pa.m3/kmol.K
Description: Universal ideal gases constant
Value to be 8314
applied:
Any comment:

Data / Parameter: MMi

Data unit: kg/kmol
Description: Molecular mass of greenhouse gas i
Value to be
Molecular mass
applied: Compound Structure
(kg / kmol)

Carbon dioxide CO2 44

Methane CH4 16

Nitrous oxide N2O 44

Sulfur hexafluoride SF6 146

Perfluoromethane CF4 88

Perfluoroethane C 2 F6 138

Perfluoropropane C 3 F8 188

Perfluorobutane C4F10 238

Perfluorocyclobutane c-C4F8 200

Perfluoropentane C5F12 288

Perfluorohexane C6F14 338

Any comment:
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Data / Parameter: MMk

Data unit: kg/kmol
Description: Molecular mass of gas k
Value to be For greenhouse gases applied values for MMi.
applied:
Molecular mass
Compound Structure
(kg / kmol)

Nitrogen N2 28

Oxygen O2 32

Carbon monoxide CO 28

Hydrogen H2 2

Nitric oxide NO 30

Nitrogen dioxide NO2 46

Sulfur dioxide SO2 64

Any comment:

Data / Parameter: MMH2O

Data unit: kg/kmol
Description: Molecular mass of water
Value to be 18 kg/kmol
applied:
Any comment:

Data / Parameter: Pn
Data unit: Pn
Description: Total pressure at normal conditions
Value to be 101325 Pa
applied:
Any comment:

Data / Parameter: Tn
Data unit: K
Description: Temperature at normal conditions
Value to be 273.15 K
applied:
Any comment:
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III. MONITORING METHODOLOGY PROCEDURE

Data and parameters to be monitored

All monitored data must be linked in time, i.e., calculations shall be performed considering only a set of
data acquired in the same time interval. As noted above, project participants may use an hour or a smaller
discrete time interval. When performing the water concentration measurement (discrete measurement) the
resulting absolute humidity will be used during the whole period between two consecutive measurements.
Measurements of moisture content shall be performed at least every 6 months.

Data / Parameter: Vt,wb

Data unit: m³ wet gas/h
Description: Volumetric flow of the gaseous stream in time interval t on a wet basis
Source of data:
Measurement Volumetric flow measurement should always refer to the actual pressure and
procedures (if any): temperature. Instruments with recordable electronic signal (analogical or digital)
are required
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Periodic calibration against a primary device provided by an independent
accredited laboratory is mandatory
Any comment: This parameter will be monitored in options C and D

Data / Parameter: Vt,db

Data unit: m³ dry gas/h
Description: Volumetric flow of the gaseous stream in time interval t on a dry basis
Source of data:
Measurement Calculated based on the wet basis flow measurement plus water concentration
procedures (if any): measurement
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures:
Any comment: This parameter will be monitored in options A and B
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Data / Parameter: vi,t,db

Data unit: m³ gas i/m³ dry gas
Description: Volumetric fraction of greenhouse gas i in a time interval t on a dry basis
Source of data:
Measurement Continuous gas analyser operating in dry-basis
procedures (if any):
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Calibration should include zero verification with an inert gas (e.g., N2) and at
least one reading verification with a standard gas (single calibration gas or
mixture calibration gas). All calibration gases must have a certificate provided
by the manufacturer and must be under their validity period
Any comment: This parameter will be monitored in options A, C, E and G

Data / Parameter: vi,t,wb

Data unit: m³ gas i/m³ wet gas
Description: Volumetric fraction of greenhouse gas i in a time interval t on a wet basis
Source of data:
Measurement Calculated based on the dry basis analysis plus water concentration measurement
procedures (if any): or continuous in-situ analyzers if not specified in the underlying methodology
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Calibration should include zero verification with an inert gas (e.g., N2) and at
least one reading verification with a standard gas (single calibration gas or
mixture calibration gas). All calibration gases must have a certificate provided
by the manufacturer and must be under their validity period.
Any comment: This parameter will be monitored in options B, D, F and H

Data / Parameter: Mt,wb

Data unit: kg/h
Description: Mass flow of the gaseous stream in time interval t on a wet basis
Source of data:
Measurement Instruments with recordable electronic signal (analogical or digital) are required
procedures (if any):
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Periodic calibration against a primary device provided by an independent
accredited laboratory is mandatory
Any comment: This parameter will be monitored in options G and H
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Data / Parameter: Mt,db

Data unit: kg/h
Description: Mass flow of the gaseous stream in time interval t on a dry basis
Source of data:
Measurement Calculated based on the wet basis flow measurement plus water concentration
procedures (if any): measurement
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures:
Any comment: This parameter will be monitored in Options E and F

Data / Parameter: C Hdb2O ,n ,h

Data unit: mg H2O/m3 dry gás
Description: Gas Moisture Content - Concentration of water r in a dry gas stream, as expressed
in the USEPA CF42 method 4 at normal conditions, in the time interval t
Source of data: Measurements according to the USEPA CF42 method 4 – Gravimetric
determination of water content
Measurement Discrete measurement procedure
procedures (if any):
Monitoring The mean value among three consecutive measurements performed in the same
frequency: day (at least 2 hours each) shall be considered. Maximum time interval between
two sets of measurement should be 6 months.
QA/QC procedures: According to the USEPA CF42 method 4
Any comment:

Data / Parameter: Tt
Data unit: K
Description: Temperature of the gaseous stream in time interval t
Source of data:
Measurement Instruments with recordable electronic signal (analogical or digital) are required.
procedures (if any): Examples include thermocouples, thermo resistance, etc
Monitoring Continuous unless differently specified in the underlying methodology
frequency:
QA/QC procedures: Periodic calibration against a primary device provided by an independent
accredited laboratory is mandatory
Any comment:
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Data / Parameter: Pt
Data unit: Pa
Description: Pressure of the gaseous stream in time interval t
Source of data:
Measurement Instruments with recordable electronic signal (analogical or digital) are required.
procedures (if any): Examples include pressure transducers, etc
Monitoring Continuous unless differently specified in the underlying methodology
frequency:
QA/QC procedures: Periodic calibration against a primary device must be performed periodically and
records of calibration procedures must be kept available as well as the primary
device and its calibration certificate. Pressure transducers (either capacitive or
resistive) must be calibrated monthly
Any comment:

Data / Parameter: pH20,t,Sat

Data unit: Pa
Description: Saturation pressure of water for a given temperature, Tt in time interval t
Source of data:
Measurement This parameter is solely a function of the gas temperature, Tt and can be found at
procedures (if any): reference [1] for a total pressure equal to 101,325 Pa
Monitoring
frequency:
QA/QC procedures:
Any comment: [1] Fundamentals of Classical Thermodynamics; Gordon J. Van Wylen, Richard
E. Sonntag and Borgnakke; 4º Edition 1994, John Wiley & Sons, Inc.

Data / Parameter: Vk,t,db

Data unit: m³ gas k/m³ dry gas
Description: Volumetric fraction of gas k in the gaseous stream in time interval t on a dry basis
Source of data:
Measurement Continuous gas analyser operating in dry-basis
procedures (if any):
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Calibration should include zero verification with an inert gas (e.g. N2) and at least
one reading verification with a standard gas (single calibration gas or mixture
calibration gas). All calibration gases must have a certificate provided by the
manufacturer and must be under their validity period
Any comment:
 UNFCCC/CCNUCC

CDM – Executive Board EB 47

Report
Annex 10
Page 16

Data / Parameter: Vk,t,wb

Data unit: m³ gas k/m³ wet gas
Description: Volumetric fraction of gas k in the gaseous stream in time interval t on a wet
basis
Source of data:
Measurement Calculated based on the dry basis analysis plus water concentration measurement
procedures (if any): or continuous in-situ analyzers if not specified in the underlying methodology
Monitoring Continuous if not specified in the underlying methodology
frequency:
QA/QC procedures: Calibration should include zero verification with an inert gas (e.g., N2) and at
least one reading verification with a standard gas (single calibration gas or
mixture calibration gas). All calibration gases must have a certificate provided by
the manufacturer and must be under their validity period
Any comment:

IV. REFERENCES

[1] Fundamentals of Classical Thermodynamics; Gordon J. Van Wylen, Richard E. Sonntag and
Borgnakke; 4º Edition 1994, John Wiley & Sons, Inc.

[2] Drying: Principles, Applications and Design; Czeslaw Strumillo and Tadeusz Kudra; 1986; Gordon &
Breach Science Publisher; Montreaux, Switzerland.

[3] “Tool to determine project emissions from flaring gases containing methane”

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History of the document

Version Date Nature of revision(s)

01 EB 47, Annex 10 Initial adoption.
28 May 2009