2. Table of Contents
1. Biogas – An Eco-Friendly Renewable Energy Source......................................1
2. Traditional Biogas Production .............................................................................1
3. Why Biogas!............................................................................................................2
4. Market for Biogas ...................................................................................................3
5. Biogas Upgrading - Growth Trend.......................................................................4
6. Current Techniques for Upgrading Biogas ........................................................4
7. Current Patenting Trends in Biogas Upgrading ................................................5
8. Conclusion ..............................................................................................................8
3. Page # 1
1. Biogas – An Eco-Friendly Renewable Energy Source
Biogas, commonly referred as gas, is one of the key renewable energy sources, produced by the
anaerobic degradation (or fermentation) of biodegradable materials such as manure, plant materials,
green waste, energy crops, household and industry wastes, sewage sludge, and municipal waste. A
methane-rich gas, it has carbon dioxide (CO2) as the second major constituent. In addition to being a
renewable energy source, other benefits of biogas include:
An alternate for fossil fuel
Low level of methane release compared to conventional manure management
Nil greenhouse gas emissions
Low emissions to environment from the waste treatment
High quality fertilizers
Produced using industrial and small-scale digesters, biogas is utilized for various purposes worldwide,
such as electricity production, vehicle fuel, cooking, water heating etc. However, exclusive treatments are
essential as the energy content in biogas differs according to applications. For instance, to use as vehicle
fuel, biogas should be upgraded to the Swedish standard specifications for vehicle fuel gas (SS 15 54
38). Thus, to enable efficient use of biogas, upgrading and the relevant technologies have gained
increased attention across the globe, fuelled by the price hike in natural gas and oil as well.
2. Traditional Biogas Production
Biogas has been in use for about 200 years now; it originated as gas lights in London, when biogas was
drawn from the underground sewer pipes to burn the street lamps in the city. In the traditional biogas
production, digesters (airtight chambers) are constructed with brick or concrete and only specific herbal
substrates could be used. In developing countries such as China, India, Pakistan, and Nepal, biogas has
been a key energy source for households, and the same scenario prevails in Africa and South America.
Though the conventional method of producing biogas has been beneficial to the economy and the
environment, there are demerits associated with them:
More construction time
Possibilities of gas leakage in case of faulty construction
Maintenance of bio-gas digesters
The above disadvantages have paved way for the new, improved, efficient technologies for biogas
production worldwide.
4. Page # 2
3. Why Biogas!
Globally, the energy requirements increase everyday, which pose the risk of energy crisis in the future, as
majority of the current need is met by crude oil. Further, environment pollutions caused by waste
materials are a major concern. With global population expected to reach 9.2 billion by 2050, there is a
pressing need to develop solutions that utilize our planet's finite resources more efficiently. Solution for
these comes in the form of biogas, which is produced from the otherwise pollutants, and hence it is
sustainable, eco-friendly energy source worldwide.
Below is the contribution-based split of biogas sources:
The composition of biogas varies depending on the source, and the gas is inflammable if methane
content (the major constituent) is 45%. To enhance the quality of the raw biogas, it is usually cleaned of
impurities such as hydrogen sulphide, oxygen, nitrogen, water and particulates, which existence would
cause corrosion and mechanical wear of the equipment in which the biogas is used.
Crops,Byproducts
and Manure
75%
Municipal and
Industrial organic
waste
17%
Sewage waste-
water treatment
facilities
8%
5. Page # 3
4. Market for Biogas
Biogas sector, the most-sustainable of biofuels, is expected to enjoy a remarkable growth over the next
two decades. The market is projected to grow from $124 billion in 2010 to $217 billion in 2016. Further,
the global biogas upgrading equipment market is expected to reach $338.5 million by the year 2016 at a
compounded annual growth rate of 22%. A total of 800 billion cubic feet per year biogas production
capacity has been installed globally, of which 11 billion cubic feet per year was expected to be live by the
end of 2012.
With the development of biogas sector, there is a constant increase in biogas plants. Thus, the global
biogas plant market is expected to reach $8.98 billion in 2017, contributed mainly by Europe and the
USA. Among the European nations, Germany has the higher biogas production and consumption; UK,
Spain and Italy are the other major biogas markets in the continent.
However, biogas production is gaining attention in Asia-Pacific, especially in Australia, New Zealand,
Japan, China and India. In China, both commercial production and at-home biogas digesters are
commonly prevalent. Liaoning Huishan Cow Farm, China’s largest biogas project, produces 38,000 MWh
electricity per year.
The key market players in the biogas industry are in the below table:
Company Region Technology
2G Bio-Energietechnik Germany
De-centralized generation of electricity and
heat via combined heat and power (CHP)
BIOGAS NORD Germany Biogas plants
BKN Biostorm Germany NA
BTA International Germany Wet Mechanical Pre-Treatment
EnviTec Biogas Germany Biogas plant construction
GHD (now DVO Inc) USA NA
HAASE Energietechnik Germany Biogas generation and upgrading
Organic Waste Systems Belgium Biogas plants
RCM Digesters California Anaerobic Digestors
Schmack Biogas Germany Biogas plants
STRABAG Umweltanlagen Germany NA
UTS Biogastechnik United Kingdom Biogas plants
6. Page # 4
Improvement ideas to intensify biogas production
The energy produced from biogas and its efficiency is dependent on its composition of the biogas,
particularly methane content, as it is to the energy content. This creates the need for enhancement of
biogas production.
The European patent EP11157784 illustrates a new method that significantly enhances the biogas
production using iron oxide nanoparticles. The iron oxide nanoparticles have been successfully tested in
anerobic digestion processes with sludge from real wastewater treatment plants, demonstrating
significant improvements of biogas production (up to 70% increase in methane production) at a low cost.
This makes the new method very market-friendly with applications in other areas such as industrial
residues, urban solid residues or even agricultural wastes.
Kemira, a European manufacturer and supplier of fertilizers and industrial chemicals, has developed the
Biogas Digestion Product (BDP) technology that uses a combination of iron, acid and trace elements to
boost biogas production. Employing this treatment method, NSR, a progressive waste recycling company
operating in Southern Sweden, has lifted the organic loading rate of its biogas plant by 33% and improved
its biogas production significantly.
A water and environment engineering company in Germany has designed a technology that uses
ultrasound to intensify anaerobic degradation in biogas plants. The device increases the release of exo-
enzymes essential for degradation of organic substrates.
5. Biogas Upgrading – Growth Trend
The process of upgrading biogas generates new possibilities for its use since it can be an ideal alternate
for natural gas, which is used extensively in several countries across the globe. However, upgrading adds
to the costs of biogas production. Thus, an optimized upgrading process is vital, consuming less energy
and producing methane-rich, high energy gas.
The global market for biogas upgrading equipment was at $125.4 million in 2011 and is projected to rise
to $338.5 million by 2016 at a 5-year compound annual growth rate (CAGR) of 22%. Europe holds the
largest market share, with estimated sales of $92.7 million in 2011. The market is forecast to reach
$250.5 million by 2016, at a CAGR of 22%. The Asia-Pacific market is estimated to grow at a CAGR rate
of 22.8% to reach $83.9 million in 2016.
6. Current Techniques for Upgrading Biogas
Anaerobic digestion of organic materials results in biogas, comprising methane, carbon dioxide and some
other unwanted compounds, such as hydrogen sulphide, nitrogen, oxygen, ammonia and siloxanes. The
major constituent methane can be used as a green energy source by upgrading biogas to natural gas
7. Page # 5
quality and injecting it into an existing gas grid, or as fuel. Upgrading of biogas signifies removal of carbon
dioxide and pollutants such as hydrogen sulphide.
The most-common commercially available biogas upgrading technologies include:
Chemical adsorption: It offers a near complete removal of hydrogen sulfide (H2S) and converts it into a
valuable compound. However, this process cannot eliminate CO2, requiring an additional scrubber
process to remove the incombustible CO2.
Pressure swing adsorption (PSA): Ideal for any geography, this methodology is used for both small
scale plants as well as high flow rates. It provides more than 95% methane enrichment, with power
demand and emissions. The major disadvantage of this process is that it requires an additional complex
hydrogen sulphide removal step.
High pressure water scrubbing: This process of biogas upgrading removes CO2 and H2S, resulting in
biogas with 98% methane content. It is the simplest among the upgrading processes, requiring no special
chemicals or equipment. However, this technique requires huge amount of water, and the changing pH
limits of the adsorption of hydrogen sulphide.
Chemical scrubbing: Similar to the water scrubbing method, it is possible to use other chemicals to
absorb CO2. Chemicals that strongly absorb CO2 (like amines) are more suitable to upgrade methane
with relatively low content of CO2 to a very high purity. However, this process has its own disadvantages
like high energy consumption for bulk CO2 removal in biogas. On the other side, for bulk CO2 removal to
obtain a CH4 purity in the range 97-98%, physical solvents (e.g. methanol, Selexol, Rectisol) consume
less energy, being more energy efficient.
Cryogenic separation: It can produce pure CH4 in large quantities, without any chemicals, and can
easily accommodate scale-up of product quantity. However, it requires several devices and equipments
for the upgrading process, and hence, an expensive option, if taken the maintenance cost of the devices.
This method is preferred if the quality of biogas treated is huge.
Membrane separation: As CH4 and CO2 have different particle size and pressure, this technique is ideal
for biogas upgrading. Further, the membrane separation unit is compact, and requires low energy and
less maintenance. But, the membranes are very expensive and get easily destroyed by solvents or
colliding solids.
7. Current Patenting Trends in Biogas Upgrading
Given the perceived imminent commercialization and requirements for alternative fuels, and its apparent
interest to scientists and technologists, an analysis of the patenting activity relating to biogas upgrading
technologies in 2013 and how it has changed over the last couple of years (2010 – till date) was done by
8. Page # 6
the patent research team at the Scope eknowledge centre. The analysis shows that a total of 89 patent
families are related to the biogas upgradation technology space. The analysis revealed that DGE DR ING
GUENTHER ENGINEERING GMBH and NALCO COMPANY were the assignees with the maximum
number of related patent families to their names.
Leading assignees with patenting frequency
DGE DR ING GUENTHER ENGINEERING GMBH and NALCO COMPANY are the most active players
currently. The former utilizes techniques such as high pressure water scrubbing and chemical scrubbing
through a solution of substituted polyamine, while the latter has extensively patented biogas upgrading
through substituted polyamine containing scrubbing solutions.
DGE DR ING GUENTHER ENGINEERING GMBH and MT BIOMETHAN GMBH are the only assignees
to have witnessed patent publications in the year 2013, while the other leading assignee NALCO
COMPANY recorded all its patents in the year 2012.
DGE DR ING
GUENTHER
ENGINEERING
GMBH
46%
NALCO COMPANY
31%
MT BIOMETHAN
GMBH
23%
9. Page # 7
Publication trend of leading assignees
The latest patent publication US2013000486A1 of DGE DR ING GUENTHER ENGINEERING GMBH
titled “METHOD FOR THE ADSORPTIVE DRYING OF PURIFIED BIOGAS AND FOR REGENERATING
LADEN ADSORBENTS” details a process for adsorptive drying of purified biogas (called biomethane)
and regeneration of laden adsorbents, wherein the dried biogas is sent to a further use, for example by
feeding into a conventional natural gas grid.
Similarly, NALCO COMPANY’s 2013 publication, US2013071307A1 titled “METHOD AND DEVICE FOR
THE ABSORPTIVE REMOVAL OF CARBON DIOXIDE FROM BIOGAS” relates to a method for the
absorptive removal of carbon dioxide from biogas using a scrubbing liquid in which carbon dioxide is
chemically bound, and to a device suitable for carrying out the method.
Other currently evolving technologies include desulphurization of biogas by introducing sulphur oxidizing
bacteria into the process tank, which is later supplied with a scrubbing liquid in the presence of oxygen,
patented by BIOGASCLEAN AS. An integrated biogas clean-up system patented by QUADROGEN
POWER SYSTEMS INC eliminates siloxanes, chlorine, oxygen and sulfur, in addition to removing volatile
organic compounds and water.
The growing demand for biogas upgradation can be evidenced from the patenting trend, with 14 patents/
patent publications filed in the first half of 2013, across geographies.
0
0.5
1
1.5
2
2.5
3
3.5
4
2010 2012 2013
DGE DR ING GUENTHER
ENGINEERING GMBH
MT BIOMETHAN GMBH
NALCO COMPAY
10. Page # 8
8. Conclusion
The market for upgrading biogas to biomethane has numerous opportunities, as this alternative energy
can be used for different applications, particularly transportation. High fuel consumption, centralized
refueling and government subsidies of vehicle capital expenses make transit buses ideal for early
adoption of compressed or liquefied biomethane usage.
However, distribution of biomethane from the point of production to the point of consumption involves
both complex regulatory issues and expenses. Further, costs involved vary significantly depending on the
availability and type of biomass feed stocks, anaerobic digester and biogas upgrading technologies used,
form of biomethane and distribution system, proximity of biomethane consumption, and economies of
scale. Rather, promising biomethane projects need to be analyzed and evaluated to determine the
viability.
