oSIST prEN ISO 20675:2021
(Main)Biogas - Biogas production, conditioning, upgrading and utilization - Terms, definitions and classification scheme (ISO 20675:2018)
Biogas - Biogas production, conditioning, upgrading and utilization - Terms, definitions and classification scheme (ISO 20675:2018)
This document defines terms and describes classifications related to biogas production by anaerobic digestion, gasification from biomass and power to gas from biomass sources, biogas conditioning, biogas upgrading and biogas utilization from a safety, environmental, performance and functionality perspective, during the design, manufacturing, installation, construction, testing, commissioning, acceptance, operation, regular inspection and maintenance phases.
Biogas installations are, among others, applied at industrial plants like food and beverage industries, waste water treatment plants, waste plants, landfill sites, small scale plants next to agricultural companies and small scale household installations.
The following topics are excluded from this document:
— boilers, burners, furnaces and lightening, in case these are not specifically applied for locally produced biogas;
— gas-fuelled engines for vehicles and ships;
— the public gas grid;
— specifications to determine biomethane quality;
— transportation of compressed or liquefied biogas;
— transportation of biomass or digestate;
— assessment and determination whether biomass is sourced sustainably or not.
This document describes the following for information purposes as well:
— the parameters to determine the size (e.g. small, medium-sized, or large scale);
— the parameters to determine the type of installation (e.g. domestic, industrial);
— the parameters to describe the type of technique;
— terms and processes in order to develop health, safety and environmental protection guidelines for biogas installations.
NOTE For an explanation of the Scope, see Annex A.
(ISO 20675:2018)
Biogaz - Production, traitement, épuration et utilisation du biogaz - Termes, définitions et classification (ISO 20675:2018)
Bioplin - Proizvodnja, priprava, nadgradnja in uporaba bioplina - Izrazi, definicije in shema razvrščanja (ISO 20675:2018)
General Information
Standards Content (sample)
SLOVENSKI STANDARD
oSIST prEN ISO 20675:2021
01-september-2021
Bioplin - Proizvodnja, priprava, nadgradnja in uporaba bioplina - Izrazi, definicije in
shema razvrščanja (ISO 20675:2018)Biogas - Biogas production, conditioning, upgrading and utilization - Terms, definitions
and classification scheme (ISO 20675:2018)Biogaz - Production, traitement, épuration et utilisation du biogaz - Termes, définitions et
classification (ISO 20675:2018)Ta slovenski standard je istoveten z: prEN ISO 20675
ICS:
27.190 Biološki viri in drugi Biological sources and
alternativni viri energije alternative sources of energy
75.160.40 Biogoriva Biofuels
oSIST prEN ISO 20675:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 20675:2021
INTERNATIONAL ISO
STANDARD 20675
First edition
2018-02
Biogas — Biogas production,
conditioning, upgrading and
utilization — Terms, definitions and
classification scheme
Biogaz — Production, traitement, épuration et utilisation du biogaz
— Termes, définitions et classification
Reference number
ISO 20675:2018(E)
ISO 2018
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oSIST prEN ISO 20675:2021
ISO 20675:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.ISO copyright office
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CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
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oSIST prEN ISO 20675:2021
ISO 20675:2018(E)
Contents Page
Foreword ........................................................................................................................................................................................................................................iv
Introduction ..................................................................................................................................................................................................................................v
1 Scope ................................................................................................................................................................................................................................. 1
2 Normative references ...................................................................................................................................................................................... 1
3 Terms and definitions ..................................................................................................................................................................................... 2
4 Abbreviated terms .............................................................................................................................................................................................. 9
5 Classifications .......................................................................................................................................................................................................10
Annex A (informative) Explanation to the scope ..................................................................................................................................11
Annex B (informative) Biogas characteristics, processes and classifications ........................................................15
Bibliography .............................................................................................................................................................................................................................20
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ISO 20675:2018(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 255, Biogas.
iv © ISO 2018 – All rights reserved
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Introduction
The technical committee on biogas (ISO/TC 255) was established in 2011 in order to
— provide liberalization and facilitation for international trade of biogas installations,
— contribute to international cooperation on technical regulations, standards and assessment
procedures,— curb discriminatory technical requirements as the main form of trade protectionism, and
— reduce and eliminate the technical barriers for international trade of biogas installations.
This document about terms, definitions and classifications is applicable for biogas production by
anaerobic digestion, gasification from biomass and power to gas from biomass sources, biogas
conditioning, biogas upgrading and biogas utilization.The availability of a set of agreed terms and definitions for biogas installations, as well as a classification
scheme for the whole biogas chain, is necessary in order to— moderate the communication between the different biogas parties through meaningful discussions,
— facilitate development of regional and national regulations and incentive programs to promote
biogas production and application,— contribute to the reinforcement of biogas installations’ safety and business competitiveness with
recognized terms and definitions that clarify the actors’ expectations related to procurement,
contracts and services as well as reporting on biogas related action plans and road maps, and
— contribute to the use of standards by facilitating their development and furthering the users’
understanding and application of standards.ISO/TC 255 intends to promote international technology exchange and to accelerate international
application of biogas (products) and equipment by developing and maintaining globally harmonized
standards.© ISO 2018 – All rights reserved v
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oSIST prEN ISO 20675:2021
INTERNATIONAL STANDARD ISO 20675:2018(E)
Biogas — Biogas production, conditioning, upgrading and
utilization — Terms, definitions and classification scheme
1 Scope
This document defines terms and describes classifications related to biogas production by anaerobic
digestion, gasification from biomass and power to gas from biomass sources, biogas conditioning,
biogas upgrading and biogas utilization from a safety, environmental, performance and functionality
perspective, during the design, manufacturing, installation, construction, testing, commissioning,
acceptance, operation, regular inspection and maintenance phases.Biogas installations are, among others, applied at industrial plants like food and beverage industries,
waste water treatment plants, waste plants, landfill sites, small scale plants next to agricultural
companies and small scale household installations.The following topics are excluded from this document:
— boilers, burners, furnaces and lightening, in case these are not specifically applied for locally
produced biogas;— gas-fuelled engines for vehicles and ships;
— the public gas grid;
— specifications to determine biomethane quality;
— transportation of compressed or liquefied biogas;
— transportation of biomass or digestate;
— assessment and determination whether biomass is sourced sustainably or not.
This document describes the following for information purposes as well:
— the parameters to determine the size (e.g. small, medium-sized, or large scale);
— the parameters to determine the type of installation (e.g. domestic, industrial);
— the parameters to describe the type of technique;— terms and processes in order to develop health, safety and environmental protection guidelines for
biogas installations.NOTE For an explanation of the Scope, see Annex A.
2 Normative references
There are no normative references in this document.
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3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp— IEC Electropedia: available at https:// www .electropedia .org/
3.1
anaerobic digestion
biological conversion of biodegradable materials by micro-organisms in the absence of oxygen creating
two main products: biogas (3.2) and digestate (3.19)Note 1 to entry: An example of anaerobic digestion is the biological conversion of the biodegradable parts of
biomass (3.9) sources, but also fossil biodegradable sources.Note 2 to entry: Wet and dry anaerobic digestion systems are applied.
3.2
biogas
gas produced by anaerobic digestion of organic matter, gasification (3.25) of biomass (3.9) or power to
gas from biomass sources and without further upgrading or purificationNote 1 to entry: Biogas comprises mainly methane and carbon dioxide and/or hydrogen and/or carbon monoxide
and/or heavier hydrocarbons with two till six carbon atoms.Note 2 to entry: Bio-syngas (3.15) is also a type of biogas.
3.3
biogas boiler
boiler which uses biogas (3.2) as fuel
3.4
biogas flare
installation to burn biogas (3.2), whether superfluous or not
Note 1 to entry: A flare is applied for biogas generated in biogas installations (3.5) or extracted from landfill sites,
among others, to avoid methane and/or hazardous compounds to be emitted into the atmosphere. A biogas flare
can be applied as safety, environmental and/or process device.Note 2 to entry: A typical flare consists of, among others, an ignition system, flame and temperature detection
system, windproof body and combustion chamber, biogas piping, valves, condensate drainage, electrical control
cabinet, installation fixtures, burner head, heat insulation and pilot or ignition burner.
Note 3 to entry: A flare can be classified in three main categories: open flare (3.43), enclosed flare (3.23) and
enclosed high efficiency flare (3.24).3.5
biogas installation
installation including its pipelines, pipes and accessories for anaerobic digestion of biomass (3.9),
gasification (3.25) of biomass and waste, upgrading of biogas (3.2), liquefaction of biogas, storage of biogas
(in raw, gas or liquid form), storage of CO , storage of auxiliaries, storage of biomass and digestate (3.19)
Note 1 to entry: Upgrading of biogas includes cooling, compressing, heating, separation, reaction in order to
purify or upgrade the biogas to a higher methane percentage.2 © ISO 2018 – All rights reserved
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3.6
biogas pipeline
system of pipework for transportation of biogas (3.2) or biomethane (3.12) with all associated equipment
and stations up to the point of delivery and outside the biogas installation (3.5)
Note 1 to entry: This pipework is mainly below ground, but includes also above-ground parts.
3.7biogas storage
buffer, gas holder, tank, vessel, bag or similar to store biogas (3.2)
Note 1 to entry: The biogas storage can be part of the fermenter.
3.8
biogenic content
organic material from biomass (3.9)
3.9
biomass
material of biological origin excluding material embedded in geological formations and/or transformed
to fossilized materialNote 1 to entry: Biomass is organic material that is plant-based or animal-based, including, but not limited to
dedicated energy crops, agricultural crops and trees, food, feed and fibre crop residues, aquatic plants, alga,
forestry and wood residues, organic agricultural, animal and processing by-products, agricultural, municipal
and industrial organic waste and residues whether or not in landfills, sludge, waste water, and other non-fossil
organic matter.3.10
biomass pipeline
digestate pipeline
system of pipework for transportation of liquid biomass (3.9) or digestate (3.19) with all associated
equipment and up to the point of delivery3.11
biomass pretreatment
treatment of biomass (3.9) with chemical, physical, thermal and biological methods in order to increase
methane production when the biomass is digested or gasified3.12
biomethane
methane-rich gas with the properties similar to natural gas derived from biogas (3.2) produced by
anaerobic digestion or gasification (3.25) or from power to gas by upgradingNote 1 to entry: Requirements for chemical and physical properties of biomethane, such as heat content, flame
characteristics, dew points, traces of chemical compounds, are part of standards for injection of biomethane in
public grids and standards for vehicle fuels and are not in the scope of, and thus not described by, this document.
Note 2 to entry: In the business, the term “upgraded biogas” is also used instead of the term "biomethane”.
3.13biomethane potential of biomass
potential of biomethane (3.12) production expressed in normal cubic metres per tonne dry matter of
biomass (3.9)3.14
biomethane storage
buffer, gas holder, tank, vessel, cylinder or similar to store biomethane (3.12)
Note 1 to entry: In case of liquefied biomethane, this often concerns vacuum insulated tanks.
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3.15
bio-syngas
type of biogas (3.2), comprising principally carbon monoxide and hydrogen, obtained from gasification
(3.25) of biomass (3.9)Note 1 to entry: Bio-syngas also contains traces of methane and carbon dioxide.
3.16
combined heat and power installation
CHP
gas engine, pilot spark ignition engine, gas turbine or fuel cell using gas to generate electrical power
and useful heat at the same timeNote 1 to entry: This is also called co-generation.
3.17
compressed biomethane
CBM
biomethane (3.12) used as a fuel for vehicles or for other purposes, typically compressed up to
20 000 kPa in the gaseous state3.18
compressed natural gas
CNG
natural gas (3.39) used as a fuel for vehicles or other purposes, typically compressed up to 20 000 kPa
in the gaseous state[SOURCE: ISO 14532:2014, 2.1.1.11, modified — the definition has been revised and Note 1 to entry has
been deleted.]3.19
digestate
remaining effluent from the anaerobic digestion process including solid fraction and liquid fraction
3.20digester
anaerobic digestion installation including reactors, tanks and related equipment
3.21
dry matter
remaining part of biomass (3.9) or digestate (3.19) after the removal of water
3.22
emergency flare
biogas flare (3.4) which is meant to combust biogas (3.2) during exceptional situations when the biogas
is not utilizedNote 1 to entry: Emergency flares can be of the type enclosed flare (3.23), enclosed high efficiency flare (3.24) or
open flare (3.43).3.23
enclosed flare
biogas flare (3.4) which consists of an enclosed combustion chamber, where the flame is invisible from
the outsideNote 1 to entry: An enclosed flare is burning more efficiently with a relatively higher temperature than an open
flare (3.43), and the burning temperature can be monitored.4 © ISO 2018 – All rights reserved
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3.24
enclosed high efficiency flare
biogas flare (3.4) which consists of an enclosed combustion chamber, where the flame is invisible from
the outside and the biogas is combusted at a monitored and automatically controlled temperature of
1 000 °C to 1 200 °C with a retention time of at least 0,3 s3.25
gasification
process that converts biogenic or fossil-based materials into carbon monoxide and hydrogen
Note 1 to entry: This is achieved by exposing the material at high temperatures (>700 °C), without combustion,
with a controlled amount of oxygen and/or steam.Note 2 to entry: Normally, the gasification is followed by conversion into methane and carbon dioxide
(methanation).Note 3 to entry: The resulting gas mixture of carbon monoxide and hydrogen is called syngas (3.58). When the
feedstock of gasification is biomass (3.9), the resulting gas mixture is called bio-syngas (3.15).
3.26gas infrastructure
pipeline systems including pipework and their associated stations or plants for the transmission (3.59)
and distribution of gas3.27
gas pipeline
system of pipework for transportation of gas with all associated equipment and stations up to the point
of deliveryNote 1 to entry: This pipework is mainly below ground but includes also above-ground parts.
3.28hydraulic retention time
theoretical average period of time a soluble compound remains in the digester (3.20)
Note 1 to entry: The hydraulic retention time (HRT) is calculated as net digester volume (m )/daily feedstock
input (m /day).3.29
hydrocarbon dew temperature
temperature at a specified pressure at which hydrocarbon vapour condensation initiates
3.30injectable biomethane
upgraded biogas (3.2) having natural gas (3.39) quality suitable to feed into the public grid and which
fulfils the legal requirements for feeding into the public grid3.31
installation owner
legal entity, a company or natural person owning the biogas installation (3.5)
3.32
liquefied biogas
biogas (3.2) which has been liquefied
EXAMPLE Liquefied biomethane.
3.33
liquefied biomethane
LBM
biomethane (3.12) which has been liquefied, after processing, for storage or transportation purposes
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3.34
liquefied natural gas
LNG
natural gas (3.39) that has been liquefied after processing for storage or transportation purposes
Note 1 to entry: Liquid natural gas is revaporized and introduced into pipelines for transmission (3.59) and
distribution as natural gas.3.35
lower heating value
amount of heat that would be released by the complete combustion with oxygen of a specified quantity
of gas, in such a way that the pressure, p, at which the reaction takes place remains constant, and all the
products of combustion are returned to the same specified temperature, T, as that of the reactants; all
of these products being in the gaseous state[SOURCE: ISO 14532:2014, 2.6.4.2, modified — “inferior calorific value” has been replaced.]
3.36methane content
mol percentage of methane in biogas (3.2) or biomethane (3.12)
3.37
methane number
rating indicating the knocking characteristics of a fuel gas
Note 1 to entry: It is comparable to the octane number for petrol. One expression of the methane number is the
volume percentage of methane in a methane-hydrogen mixture that in a test engine under standard conditions
has the same tendency to knock as the fuel gas to be examined.[SOURCE: ISO 14532:2014, 2.6.6.1]
3.38
mixer
agitator within a digester (3.20) homogenizing the biomass (3.9) in the digester
3.39
natural gas
complex gaseous mixture of hydrocarbons, primarily methane, but generally includes ethane, propane
and higher hydrocarbons, and some non-combustible gases such as nitrogen and carbon dioxide
Note 1 to entry: Natural gas can also contain components or containments such as sulfur compounds and/or
other chemical species.[SOURCE: ISO 14532:2014, 2.1.1.1]
3.40
natural gas network
network which is either a transmission (3.59) network or a local distribution system
Note 1 to entry: Network and grid have the same meaning.3.41
normal cubic metres of gas
volume of one cubic metre for real dry gas at ISO Standard Reference conditions of 15 °C and 101 325 kPa
Note 1 to entry: In the industry, 0 °C and 101 325 kPa are also often used; however, in this document, the ISO
Standard Reference conditions are used.6 © ISO 2018 – All rights reserved
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3.42
odorization
addition of odorants, normally intensively smelling organic sulphur compounds, to natural gas (3.39) to
allow the recognition of gas leaks by smell at very low concentration (before a build up to a dangerous
gas in air concentration can occur)Note 1 to entry: Natural gas is normally odourless. It is necessary to add an odorant to the gas fed into the
distribution system for safety reasons. It permits the detection of the gas by smell at very low concentrations.
[SOURCE: ISO 14532:2014, 2.8.2]3.43
open flare
biogas flare (3.4) from which the burning flame is visible from the outside
Note 1 to entry: This is also called external combustion flame burner.
Note 2 to entry: The flame burner combustion is not optimal; the combustion temperature is relatively low.
3.44organic dry matter
part of biomass (3.9) or digestate (3.19) which consists of dry matter containing carbon and originating
from living materialsNote 1 to entry: Instead of organic dry matter, the term “total volatile solids” is also used.
3.45organic loading rate digester
amount of volatile organic dry matter (3.44) entering the anaerobic digester (3.20) over time, measured
in kilograms per cubic metre digester volume per dayNote 1 to entry: The organic load gives an indication on biological degradation of the substrates (3.56). It provides
information on nutrient supply levels of the microorganisms involved, overload or undersupply of the system as
well as resulting technical and process control measures to be taken. The organic load describes the efficiency of
the anaerobic digester.3.46
pipeline network
system of interconnected pipelines, both national and international, that serve to transmit and
distribute natural gas (3.39)[SOURCE: ISO 14532:2014, 2.1.2.1, modified — “grid” has been replaced by “network”.]
3.47power to gas
gas generated from electrical power from biomass (3.9) origin
3.48
raw biogas
biogas (3.2) directly from the digester (3.20) which is not conditioned, so it is not yet dried and cleaned
3.49recovered gas
gases such as hydrogen, carbon dioxide, carbon monoxide and/or complex gaseous mixtures of
hydrocarbons, primarily methane, but generally includes ethane, propane and higher hydrocarbons,
and some non-combustible gases such as nitrogen and carbon dioxide which are recovered as a by-
product or residual product of gases from, for example, industrial or thermochemical processes not
being biogas (3.2) and not produced from biomass (3.9)Note 1 to entry: Recovered gas can also contain components or containments such as sulfur compounds and/or
other chemical species.© ISO 2018 – All rights reserved 7
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Note 2 to entry: Usually, these gases have a fossil origin.
3.50
relative density
ratio of the mass of a gas contained within an arbitrary volume to the mass of dry air of standard
composition that would be contained in the same volume at the same reference conditions
3.51renewable non-biogenic gas
gas such as hydrogen, carbon dioxide, carbon monoxide and/or complex gaseous mixtures of
hydrocarbons, primarily methane, but generally includes ethane, propane and higher hydrocarbons,
and some non-combustible gases such as nitrogen and carbon dioxide which are produced from
renewable sources not being biogas (3.2) and not produced from biomass (3.9)Note 1 to entry: Examples are gases produced via power to gas (3.47) processes from renewable power from
solar, wind, hydropower or geothermal sources, but not from biomass sources.3.52
service provider
legal entity or a company operating on request of the biogas installation owner (3.31) and/or maintaining
the biogas installation (3.5)3.53
solid retention time
period of time expressed in days the biomass (3.9) is in the digester (3.20) for anaerobic digestion
Note 1 to entry: The solid retention time (SRT) is calculated as the net capacity for biomass content in the
digester (kg)/daily feedstock input (kg/day).3.54
specific biogas production
standard state volumetric biogas (3.2) production expressed in normal cubic metres per liquid volume
in cubic metres of the digester per day3.55
specific biogas yield
standard state volumetric biogas production expressed in normal cubic metres per kilogram organic
dry matter (3.44) of the feedstock3.56
substrate
part of the biomass (3.9) which is biodegradable and converted by microorganisms and/or enzymes as
catalyst into biogas (3.2) and/or degradable by gasification (3.25)3.57
supplier of the biogas installation
legal entity or a company which designs, manufactures or constructs and delivers the biogas installation
(3.5) to the biogas installation owner (3.31)3.58
syngas
gas, comprising principally of carbon monoxide and hydrogen, obtained from gasification (3.25) of
fossil fuels3.59
transmission
activity intended to convey gas from one place to another through pipelines in order to supply gas to
distribution systems or to industrial consumers8 © ISO 2018 – All rights reserved
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3.60
treated biogas
biogas (3.2) which is dried until a water dew point of at least 10 °C and conditioned by cleaning from
contaminants like hydrogen sulphide and siloxanes, but from which the CO and N percentages have
2 2not been decreased yet
3.61
treated digestate
digestate (3.19) after partly removing the nutrients such as phosphates, nitrogen and/or water
Note 1 to entry: Treatment can be done by drying, pelletizing, and separating water and nutrients.
3.62volatile fatty acid
fatty organic acid containing less than six carbon atoms
Note 1 to entry: These are intermediate products of the biogas (3.2) production process.
3.63waste water treatment gas
biogas (3.2) produced by anaerobic waste water treatment installation or waste water treatment sludge
digestionNote 1 to entry: Waste water treatment gas is often mentioned as sewage gas.
3.64
water dew point
temperature at a specified pressure at which water vapour condensation initiates
Note 1 to entry: For any pressure lower than the specified pressure, there is no condensation of water vapours at
this water dew point temperature.[SOURCE: ISO 14532:2014, 2.6.5.1.1]
3.65
Wobbe index
calorific value on a volumetric basis at specified reference conditions, divided by the square root of the
relative density at the same specified metering reference conditionsNote 1 to entry: The Wobbe index is specified as superior (denoted by the subscript “S”) or inferior (denoted by
the subscript “I”), depending on the calorific value.[SOURCE: ISO 14532:2014, 2.6.4.3]
4 Abbreviated terms
CBM Compressed biomethane
CHP Combined heat and power plant
CNG Compressed natural gas
HRT Hydraulic retention time
LBM Liquefied bio methane
LNG Liquefied natural gas
SRT Solid retention time
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5 Classifications
Biogas installations can be classified in different types (e.g. domestic, farm, industrial) and different
sizes (e.g. domestic scale, small scale, medium scale and large scale). Also, parts of the installations can
be classified in different pressure classes. Classifications are descriptions and categorizations used for
information and better understanding and do not contain technical requirem...
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