Friday, November 16, 2018

3 Benefits of Biomethane Gas to Grid AD Plants


Biomethane production and anaerobic digestion gas to grid is a development which is of great interest and show just what improved technology can do. (The grid we refer to is the natural gas grid (i.e. the national natural gas pipeline system.)

It's a mature technology now, with about 100 active plants in Germany alone.

For those farms and business seeking to get started in the UK, CHP and gas to grid is probably close to a minimum 18 month project from inception to completion and new gas-to-grid plant RHI applications are only good until early 2020.

3 Advantages of Biomethane Gas to Grid AD Plants


The difference between a “gas to grid” biogas plant and a normal anaerobic digestion plant is that rather than use the biogas produced to make electricity, we take it a step further.


We clean up, the raw biogas from the digester in a process that we call “upgrading”.

The specification of upgraded biogas is for a product gas which is suitable to be injected into the natural gas grid.

1. Environmental Benefits

The integration of enriched biomethane into the national gas grid has several key environmental benefits.

On a full lifecycle basis Bio-CNG provides a 72% reduction in CO2 emissions as well as being exceptionally clean, with ultra-low particulate emissions and ultra-low NOx emissions.

2. Financial Benefit for the Transport Company/ User – CNG Fuel Costs Less

In fact CNG users commonly report about a 30% reduction in fuel costs.

3. The Biomethane Producer Makes a Profit

Image shows a bus powered by biomethane via Biomethane Gas to Grid

They get two sources of income:

First, there are UK Renewable Heat Incentive (RHI) payments.

Second, they are paid by the grid Company for the biomethane gas produced.

Those are just a few of the benefits of gas to grid AD plants.

For more information on this subject visit our AD website.

Support biogas! It's a Major Renewable Energy Source!

Sunday, October 21, 2018

Home Biogas How to get energy from Trash - Chinese Home Digester Design

This is our version of the basic information on buried Chinese home biogas plant designs, as provided very expertly on the Eco Tipping website.


Why Eco Tipping? We assume this was features on the Eco Tipping website because if everyone was to adopt home biogas as an energy source the fate of planet earth would be tipped toward being sustainable.
The following is the part of the original article which we have used to make the above video:
The basic biogas system involves an anaerobic digester (usually underground) with an inlet pipe, an outlet pipe, and a tube for the biogas.
The feedstock is a combination of plant and animal wastes, plus water. Crop residues as well as tree litter and weeds are suitable, as are manure from pigs, cows, chickens, and humans.
It ferments in the digester tank to produce biogas, which contains 60-70% methane (CH4).
The energy content is 22 gigajoules (GJ=1 billion joules) per m3, about the same as 0.5 liter of kerosene.
The basic chemical reaction is: 2 C + 2 H2O » CH4  + CO2. The process occurs with the aid of bacteria, and is temperature sensitive (range is 8-60° C).
Under ideal conditions, a 10 m3 digester can supply enough gas for cooking and lighting for a family of five. Biogas can also be used for fueling farm machinery and for power generation.
Both the liquid sludge from the outlet pipe and the sediment at the bottom of the tank are very good fertilizers. via EcoTipping

The following are our views on Home Biogas Plants:

Home biogas is widely produced in developing regions of the world. It has been used in the greatest numbers in rural China where exceeding 30 million of thse plants ahve been built.

Home biogas basics Chinese anaerobic digestion plant buried digester design information.
Unfortunately, the design relies entirely on the skill of local builders to make these plants gas-tight. Doign that is not easy, and leaks may occur after backfilling the tanks when repairs would be very difficult.

There is also no way to test this design of home biogas plant before it is filled with digestate. Many of thse plants lie unused due to such difficulties.

Thta's why designs using purpose built tanks above ground are much better, as long as they are ewll insulated from cold climates, and can be kept warm for efficient biogas production.

Israeli startup Home Biogas has developed a relatively affordable home-sized biogas unit that allows people to convert their own waste into fuel.

In Israel, where temperatures get quite hot in summer but where winter lows have included snowfall, the start-up company Eco-gas Home Biogas has launched commercial biodigesters for the home and small institution.

Many people say that to make your own home energy the alternative method of usign solar panels is better. We do not agree. Solar panels are expensive and the high initial costs takes perhaps 10 year to repay in energy cost savings. The initial cost of a home biogas plant is lower than a solar array. In addition to the lower upfront cost, home biogas does not require a grid-tie or any type of energy storage, as energy is stored in gas form and used on-demand when needed.


Friday, October 05, 2018

The Food for Fuel Debate and Biogas


Food versus Fuel Facts About Biogas Energy

There is no doubt that until recently there was a powerful concern that in nations such as the US, parts of South America, and the EU (especially in Germany), renewable biofuel production would reduce food available to eat.

The result would be rising food prices for us all.

For a while, governments were so keen to encourage renewable fuels, to reduce climate-changing emissions that they seemed to forget that people must come first when food is needed.

Some were saying things like:

"Crops Used for AD raise the price of food", and that "People could go hungry as a result".

But, this was not primarily aimed at biogas production.

The technology used for the original diesel-fuel-replacement biofuels, which were widely subsidized was, and still is, the chemical conversion of vegetable oils into bio-diesel.

This is a diesel fuel replacement which is added to the fuel bought at filling stations, and lots of it is still produced.

The production of biogas using the anaerobic digestion process is a completely different process.

AD processes once received subsidies for crops such as maize and beet as well as agricultural biomass waste and, in parts of the EU.

As a result of the spin-off from the main biodiesel "Food-for-Fuel" debate, such subsidies have all-but ceased. They are now historical and are no longer granted.

Unfortunately, anaerobic digestion and biogas has become erroneously tarred with the same "Food versus Fuel" brush. This is wrong in our opinion.

Image illustrates the food for fuel biogas debate.

When crops are grown for AD, this is usually done as part of a traditional agricultural rotation, helping farmers to improve food crop yields and soil quality, or these are grown on marginal land not suitable for food crops.

The amount of land used for growing crops for energy generation in England is less than 1%. This figure is even lower across the devolved nations of the UK. More land is used for golf courses.

The ADBA analysis also shows that the growing of these crops has had no discernible impact on food supply for humans or livestock.

The following are just some of the reasons to support the agricultural production of biogas fuel, when based upon using crop and other waste.

AD has a vital role to play in recycling wastes, reducing greenhouse gas emissions, and producing the renewable energy, clean transport fuel, and soil-restoring biofertiliser that the UK desperately needs.

Source: AD and Bioresources News Issue 41, Autumn 2018

http://adbioresources.org/uploads/adverts/Updated_FINAL_ISSUE_41_for_WEBSITE.pdf

For another article about biogas myths including food for fuel subsidies visit here.


Tuesday, September 18, 2018

What is Biofertilizer? Renewable Fertilizer Defined and Explained


What is Biofertilizer?

Biofertilizer is a product of fermentation of organic material in water which contains living microorganisms which, when applied to seeds, plant surfaces, or soil, enriches plants with foods to create a healthy biology, and supplies minerals for biological processes to digest.


Through the use of biofertilizers, healthy plants can be grown, while enhancing the sustainability and the health of the soil.

Since the microorganisms play several roles, a preferred scientific term for the beneficial bacteria in biofertilizers is "plant-growth promoting rhizobacteria".

Biofertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorus, and stimulating plant growth through the synthesis of growth-promoting substances.

Biofertilizer can be made in a variety of ways, but biogas plants are the main producers, and the anaerobic digestion and biogas industry calls it 'digestate".


All biogas plants (also known as "Anaerobic Digestion Plants" or "Methane Digesters") produce digestate (renewable biofertilizer) as a by-product when making biogas.


Some Anaerobic Digestion Plants produce a digestate that is not suitable for use as a biofertiliser. In most of these cases, the digestate is usually suitable after pasteurization, in accordance with the Animal By-products Regulations.


Many digestate biofertilizer users have reported that not only is crop growth increased by correctly applied digestate, they also witness a biocide effect where a number of plant diseases are reduced.

Watch What is Biofertilizer? on YouTube at: https://youtu.be/UKpDdfbm8Vw


Visit the "Must-Have Biofertilizer Resource List" at https://anaerobic-digestion.com/biof .

Saturday, September 08, 2018

Home Biogas You Don’t Have to Be Poor or Living Off-Grid to Find This Useful

Home Biogas: New home biogas products are gaining great reviews suggesting that you don’t have to be poor or living off-grid to find it useful to make your own worthwhile biogas cooking fuel.

In the following article, Samuel Alexander a Research fellow, at the Melbourne Sustainable Society Institute, University of Melbourne describes his experience of one such system:

Home biogas: turning food waste into renewable energy


Image of the home biogas system which offers a zero-emissions alternative to paying for fossil gas.
The home biogas system offers a zero-emissions alternative to paying for fossil gas. Samuel Alexander, Author provided
Samuel Alexander, University of Melbourne
Last night I cooked my family a delicious pasta dinner using biogas energy. This morning we all had eggs cooked on biogas. I’m not sure what’s for dinner tonight, but I know what will provide the energy for cooking: biogas.
And not just any biogas – it’s home biogas, produced in our suburban backyard, as part of my ongoing “action research” into sustainable energy practices.

Read more: Biogas: smells like a solution to our energy and waste problems

In an age of worrying climate change and looming fossil energy decline, the benefits of biogas are obvious. It is a renewable energy source with zero net greenhouse emissions. And yet its potential has largely gone untapped, at least in the developed world.
Based on my research and experience, I contend that home-produced biogas is an extremely promising technology whose time has come. In fact, I believe it could provoke a domestic green energy revolution, if only we let it.

What is biogas?

Biogas is produced when organic matter biodegrades under anaerobic conditions (that is, in the absence of oxygen). This process produces a mixture of gases – primarily methane, some carbon dioxide and tiny portions of other gases such as hydrogen sulfide.
When the biogas is filtered to remove the hydrogen sulfide, the resulting mixture can be burned as an energy source for cooking, lighting, or heating water or space. When compressed it can be used as fuel for vehicles. On a commercial scale biogas can be used to generate electricity or even refined and fed into the gas grid.
The types of organic matter used to produce biogas include food waste, animal manure and agricultural byproducts. Some commercial systems use sewage to produce and capture biogas.

Biogas benefits

The primary benefit of biogas is that it is renewable. Whereas the production of oil and other fossil fuels will eventually peak and decline, we will always be able to make biogas as long as the sun is shining and plants can grow.
Biogas has zero net greenhouse emissions because the CO₂ that is released into the atmosphere when it burns is no more than what was drawn down from the atmosphere when the organic matter was first grown.
As already noted, when organic matter biodegrades under anaerobic conditions, methane is produced. It has been estimated that each year between 590 million and 800 million tones of methane is released into the atmosphere. This is bad news for the climate – pound for pound, methane is a far more potent greenhouse gas than CO₂.
But in a biogas system this methane is captured and ultimately converted to CO₂ when the fuel is burned. Because that CO₂ was going to end up in the atmosphere anyway through natural degradation, biogas has zero net emissions.
There are other benefits too. The organic matter used in biogas digesters is typically a waste product. By using biogas we can reduce the amount of food waste and other organic materials being sent to landfill.
Furthermore, biogas systems produce a nutrient-rich sludge that can be watered down into a fertiliser for gardens or farms. All of this can help to develop increased energy independence, build resilience and save money.

My biogas experiment

In the spirit of scientific research, I installed one of the few home biogas systems currently available, at a cost of just over A$1,000 delivered, and have been impressed by its ease and functionality. (Please note that I have no affiliation, commercial or otherwise, with the manufacturer.)
In practical terms, I put in about 2kg of food waste each day and so far I have had enough gas to cook with, sometimes twice a day. If I ever needed more gas, I could put in more organic matter. I will continue to monitor the system as part of my research and will publish updates in due course. If interested, watch this space.
My personal motivation to explore biogas (related to my research) arises primarily from a desire to decarbonise my household’s energy use. So far, so good. We have disconnected from the conventional gas grid and now have more money to spend on projects such as expanding our solar array.
Given the alarming levels of food waste in Australia, I also like the idea of turning this waste into green energy. My neighbours kindly donate their organic matter to supplement our own inputs, increasing community engagement. When necessary I cycle to my local vegetable market and enthusiastically jump into their large food waste bin to take what I need, with permission.
They think I’m mad. But, then, I think using fossil fuels is mad.

Hurdles and hopes

Home biogas is widely produced in developing regions of the world. The World Bank and the United Nations actively encourage its use as a cheap, clean energy source. China has 27 million biogas plants.
But developed regions, including Australia, have been slow to exploit this vast potential. Given that Australia is one of the most carbon-intensive countries on Earth, this is unfortunate.
The failure to embrace home biogas is partly due to a lack of clear regulations about its use. Where is the Home Biogas Act? Almost every Australian backyard has an independent gas bottle to power the ubiquitous barbecue, so clearly storing gas in the backyard is not a problem. My biogas system came with robust safety certificates, warranties and insurance, and these systems do not feature high-pressure gas pipes.

Read more: Capturing the true wealth of Australia’s waste

Home biogas production is unusual. But I believe that state governments should draw up legislation to accommodate it, and that local councils should offer advice and assistance to householders who are interested in taking it up. Hoping for progress in this regard, I recently made a submission to the Victorian government as part of its Waste to Energy consultations.
My own carefully managed experiment demonstrates how home biogas can be used safely and successfully. Nevertheless, biogas is a combustible fuel and needs to be filtered for poisonous hydrogen sulfide. Like any fuel, it should be respected and used responsibly. But biogas need not be feared. Fossil gas is far more dangerous anyway.The Conversation
Samuel Alexander, Research fellow, Melbourne Sustainable Society Institute, University of Melbourne
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Please give us your comments on your experiences with home biogas systems, in the comments section blow this article..

Friday, September 07, 2018

Proof That Biomethane Is Cleaning-Up On The Biogas Market

Biomethane is cleaning-up on the Biogas Market. The business sector is growing rapidly with support and both political and monetary investment going forward in many countries.

This is demonstrating that building AD plants with additional equipment to produce biomethane, which is nothing more than thoroughly cleaned-up biogas, is thought to be worth the additional investment by many people.

Biomethane cleaning up on biogas market article feature image.
Biomethane Advances in popularity over raw biogas

Biogas has many uses, but the demand for biomethane which is a fuel equivalent to Natural Gas is simply insatiable!

Just consider the unimaginable amount of energy needed to run transport vehicles and the hype which is peddled daily by governments, to pollution hit city dwellers to convince us all that electric cars are the cure and are coming in just a year or two. Who truly believes that any more?

Now let's give you the PROOF that all manner of people, politicians and investors are now promoting biomethane and biogas plant projects which will produce biogas which will be upgraded to biomethane.

California Legislature Green-Lights Pair of RNG Bills

On the final day of California’s 2018 legislative session, a bill sponsored by the Coalition for Renewable Natural Gas (RNG Coalition) that would pave the way for a state renewable natural gas (RNG) procurement program was approved, passing 29-10 in its reconciliation in the Senate.

As approved, S.B.1440 authorizes the California Public Utilities Commission (CPUC), in consultation with the California Air Resources Board, to adopt a biomethane (RNG) procurement program that would benefit ratepayers, proves to be cost-effective, and advances the state’s environmental and energy policies, the coalition explains. The legislation was introduced this year by State Sen. Ben Hueso.

“A renewable natural gas procurement program would create market certainty that industry developers need to access investment capital and build new projects in California,” says Johannes Escudero, CEO of the RNG Coalition. “Nearly 30 states have [renewable portfolio standard] programs in place, requiring electric utilities to procure and use increasing proportions of renewable energy. States should set similar renewable natural gas targets for gas utilities to create new in-state jobs, decarbonize our pipeline systems, reduce emissions and improve air quality.”

The RNG Coalition’s other sponsored bill this year, A.B.3187, passed the legislature by comfortable margins, the group notes. The bill requires the CPUC to open a proceeding to consider options to promote the in-state production and distribution of biomethane, including recovery in rates of the costs of interconnection infrastructure investments, by no later than July 1, 2019. It was unanimously approved (38-0) by the Senate on Aug. 27 after having passed the Assembly earlier this year. via CaliforniaRNG

New Technologies in the Works for Onboard CNG Storage

More refuse companies are investing in compressed natural gas (CNG) sourced from cleaned biomethane (renewable natural gas), storing it on board in cylinders. For some time, storing this high-pressure fuel on trucks came with challenges for fleets, and though the industry has since taken down significant hurdles, there are new innovations in the pipeline for greater efficiency.

“Fuel storage on board gas vehicles is well proven and established. But with all industries and technologies, there is continuous improvement going on. And in coming years, there will be changes and improvements to natural gas fuel and dispensing systems,” projects Barnes. via OnboardCNGStorage

Renewable natural gas program for Minnesota customers

Centerpoint Energy filed a five-year pilot program proposal with Minnesota`s Public Utilities Commission (PUC) on Thursday, which will give customers the option to purchase renewable natural gas, or biomethane, as an alternative to traditional gas.

The pilot would be the first of its kind to offer distribution of renewable gas directly to customers, although other utilities use it in a more "decentralized sense," Margaret Cherne-Hendrick, senior policy associate at Fresh Energy said in an interview with Utility Dive.

If approved, customers will be able to choose renewable gas for approximately $4 more per therm, although the price won`t be set until after the PUC approves the pilot, according to Centerpoint`s website. The state`s PUC is expected to make a final decision on the program in January of 2019.

Many in the industry will likely favor biomethane because the infrastructural transition is easier and cheaper for utilities she says. However, customers should be aware of what they`re paying for.

In a survey conducted by CenterPoint, the utility found half the approximately 1,550 customers surveyed were willing to pay $5 and $25 more per month for renewable gas, according to the Minneapolis Star Tribune, and the utility is operating under the assumption that 1% of its 800,000 customers would be willing to participate. via CenterPoint Energy

UK John Lewis cuts CO2 fumes by over 80 percent in LARGEST ever green trial

JOHN LEWIS has teamed up with green gas supplier CNG Fuels to launch the UK’s largest-ever trial aimed at showing how biomethane, a low carbon alternative to diesel, can slash HGV emissions and costs, writes Maisha Frost. via John Lewis cuts CO2 fumes

Biogas Market Size, Share - Industry Share Report 2024

Global biogas market size is anticipated to witness substantial growth owing to government led stringent regulations pivoted towards greenhouse emissions. In 2016, Singapore government had led directive pertaining to carbon emission reduction by 36% by 2030 below 2005 levels.


Rising energy security concern due to depleting conventional resources will positively steer the global biogas market. In 2017, The Asian Development Bank has funded waste to energy (WTE) projects in agreement with Dynagreen environmental protection group across China.


Renewable resource integration with demand for cost effective clean source of energy will positively drive the global biogas market share by 2024. Government initiatives pertaining to waste management will propel the global industry. In 2017, Australian government in support to waste to energy technologies have launched a USD 2 million program in Victoria.


Inconsistency of waste composition and complex facility designs will hamper global biogas market. Urbanization and economic growth are diversifying the technology pertaining to lower generation rates, improved treatment technology and waste composition techniques. via Biogas Market 2024

Biomethane on the National Gas Grid – A First for Ireland’s Bio-Economy

In 2018, Gas Networks Ireland will introduce renewable gas onto the Irish gas network for the first time writes Pádraic Ó hUiginn. Renewable gas, also known as biogas or greengas, will be introduced into the Irish market as a means of further reducing emissions. As natural gas and biomethane are interchangeable, renewable gas can be used in the same way and in the same appliances as natural gas. Customers, business and domestic, would never be aware that the gas they are using is a renewable alternative. via A First for Ireland

More Reports:

The Biomethane Market to Witness Robust Expansion by 2025 released by QYResearch provides a basic overview of the Biomethane industry, ...
Global Biomethane market is growing at a CAGR of 6.3% between 2018 and 2025 – QY Research
Business Analyst
This report studies the Biomethane market size (value and volume) by players, regions, product types and end industries, history data 2013-2017 and ...
Biogas and Biomethane Market by Manufacturers, Regions, Types and Application and Forecast to ...
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Biogas and Biomethane Market report provides overall insights into the crucial and Industry chain structure, Biogas and Biomethane remarkable ...
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Global Biogas and Biomethane Market Analysis Report ponders most recent industry patterns, improvement viewpoints, advertise picks up, and ...

Sunday, August 26, 2018

The Dangers of Biogas - 7 Known and 3 Unexpected AD Hazards

There are dangers of biogas just as there are dangers inherent in everything we do. The most obvious biogas dangers come from the fact that it is an explosive gas when mixed air in the right proportions.

However, there are also anticipated dangers of biogas plants which the public authorities and individuals raise during consideration of planning applications, which this article also discusses with examples, in section 2.

Finally, in section 3 below we have included three surprising unexpected dangers of biogas which few if any people have foreseen, with:

  • honey which became coloured due to an anaerobic digestion plant locally, and 
  • estrogen, antibiotics which persisted in dairy farm waste after AD treatment
  • worries about aluminium roof collapse if sulphur leaks out of the biogas.
Image - cartoon suggests the dangers of biogas.


1. Normally Accepted Biogas Hazards

The normally accepted dangers of biogas are summarized in the list of 7, below:

  1. Fire/Explosion
  2. Asphyxiation
  3. Disease
  4. Methane
  5. Carbon Dioxide
  6. Hydrogen Sulfide
  7. Ammonia.

Precautions to Limit the Normally Accepted Dangers of Biogas

Standard biogas plant safety procedures will major on the following actions to keep plant staff safe:

  • Observe All Manufacturer Warnings with Rigour, create Site Safety Policies and implement procedures to ensure all staff and each visitor is trained to avoid every biogas plant hazard which could cause injury or ill-health.
  • Conduct Safety Walk-Throughs/ Plant and Equipment Inspections Regularly
  • Use and Maintain Gas Sensors
  • Use the relevant Personal Protective Equipment via Biogas Safety

2. Dangers Raised During Biogas Plant Planning Discussions

Dangers of biogas production as an alternative energy source for rural areas

Biogas is a mixture of 55-65% Methane, 30-35% Carbon Dioxide and Moisture, Hydrogen Sulphide, Nitrogen and Hydrogen making up the balance.

Its heating value is around 600 B.T.U. per cubic feet. Biogas production is a biological process without oxygen in which organic matters are converted into biogas by bacteria, because organic matters are the food source for methane producing bacteria. About one cubic feet of biogas may be generated from one pound of cow dung at around 28°C.

This is enough to cook a day's meals for 4-6 people. In anaerobic process, the bacteria requires both Carbon and Nitrogen, but they consume Carbon roughly 30 times faster than Nitrogen.

Biogas is not poisonous, although this may be improved by filtering it through limewater to remove CO2, iron filings to absorb corrosive H2S and Ca2Cl to extract the water vapour.

The only danger is by the explosion of the plant and mixed with air and fire. Thus proper maintenance of the Biogas plant is important to prevent the leakage.

via Biogas production as an alternative energy source for rural areas

Villagers fear biogas plant in Canwick would cause ‘unnecessary danger’

February 2018: Plans for a new biogas plant in Canwick have provoked an angry response from fearful local residents, with even the Environment Agency and Lincolnshire Fire and Rescue weighing in to say that the development should not be approved in its current form. via Canwick danger’

THE Energy Regulatory Commission has not licensed any of the bottled biogas products which are ... are highly explosive, hence pose a lot of danger if not well handled. "The people bottling biogas need to get safety approval first," ERC director ... via Kenya: Traders Selling Bottled Biogas Illegally - Kenya: Traders

Anaerobic digester plans stymied in Franklin - News - Milford Daily News

After hearing the pleas of several concerned residents, Town Council on Wednesday tabled zoning changes that sited an anaerobic digester plant for a Pond Street property.

... The questions about anaerobic digestion, a biological process that converts organic waste into energy, overshadowed the positives of the burgeoning technology.

With support from the Economic Development Committee, Town Administrator Jeffrey Nutting and officials in the Department of Planning and Community Development had hoped to tweak the zoning to allow for an anaerobic digester facility on the former Pond Street sewer bed.

... a day after the Planning Board voted not to recommend the zoning changes, residents who live on or near Pond Street attended the council meeting ready to fight the prospect of an anaerobic digester in their backyard.

"I want you to take into consideration what anything seeping into the ground, or going into the air … could do to our community — the town we love so much," said Sandra Verhaegen. "Is the $500,000 to $1 million worth it? Probably not. Look to new businesses (to fill the property). Do we really want something in our community that isn’t tested?"

According to the Environmental Protection Agency, the "biogas" or gas produced when the anaerobic digester breaks down waste is comprised of methane, hydrogen sulfide, a highly toxic and flammable gas with a distinct rotten egg smell, and carbon dioxide.

Residents worried that problems [of the dangers of biogas] with the plant, such as a fire or leak, could put them in immediate danger. And they feared the increased truck traffic that would accompany the plant.

Councilors expressed the same concerns. via Anaerobic digester plans stymied

3. Unexpected Dangers of Biogas

Waste from M&M's Candy Causes Honey to Turn Green in France

M&M candies come in every color of the rainbow – but what if honey came in the color of M&Ms?

Distraught beekeepers in Northeastern France are facing just that conundrum, as honey from their apiaries has been turning up in shades of green and blue.

After weeks of perplexing investigation, the farmers found the candy colored honey to be caused by waste from nearby Agrivalor biogas plant, which has been processing M&M’s waste.

The farmers in Ribeauville, Alsace are just 2.5 miles away from the biogas plant, a short jaunt for their bees to travel and pollinate before returning to the hive. In the past the biogas plant threatened no danger to their business, but since processing waste from the colorful shells of M&M’s, the beekeepers felt an immediate effect. Bees from around twelve apiaries have been returning to the hive with blue and green debris, which gets directly transferred to the honey they yield.

Honey appearing in colors other than amber is needless to say, unsellable. The murky blue and green sweet stuff isn’t being packaged as a new M&M flavor, but instead is being thrown in the trash.

These beekeepers are already facing adversity, with increasing bee mortality rates killing off many of their producers they can’t afford to lose the honey they do make. Coupled with the effects of harsh winters, the apiaries are already in a jam.

[The AD plant operator] has been notified and has begun cleaning up the mess, but the beekeepers are still stuck with green honey. via Honey Green

Estrogen, antibiotics persisted in dairy farm waste after advanced treatment, study finds

When University at Buffalo chemists began studying waste disposal at a dairy farm in New York State, they thought that the farm's advanced system for processing manure would help remove estrogens and antibiotics from the excrement.

Instead, the scientists found that the chemicals largely persisted in the treated materials, which are typically reused as fertilizer and animal bedding on the farm.

The waste management process—an advanced anaerobic digestion system—also converted a less harmful form of estrogen in the manure into a form that may pose a greater ecological threat.

The study underscores how far waste treatment techniques have fallen behind the times.

Hormones and antibiotics, if not removed from waste, can migrate into the environment and threaten wildlife. Estrogens, for example, can enter rivers and lakes, causing male fish to develop female traits—a phenomenon that can harm reproduction. Rogue antibiotics pose a different kind of challenge, encouraging the spread of antibiotic resistance, in which disease-causing bacteria stop responding to drugs.

... "One of the messages of our work is that even anaerobic digestion, an advanced treatment, doesn't totally remove these chemicals which may pose a danger to the environment. We need to start looking closely at additional treatment techniques to identify better practices."

The research, funded by the New York State Pollution Prevention Institute, was published in two recent papers. via Estrogen, antibiotics persisted

Waste Not, Pollute Not 

This is part of IEEE Spectrum's special report: Critical Challenges 2002: Technology Takes On

Cow Power - Danger of Sulphur Precipitation to Aluminium Roof Corrosion and Potential Eventual Collapse

...each of DDI's three barns will be warmed by water pipes running under the concrete floor. The hot water, which will be heated by biogas power, will keep the manure flowing into the digester even in the dead of winter. So the electricity will keep flowing, too.

That electricity will be generated by four microturbines from Capstone Turbine Corp., Chatsworth, Calif. [see "Networking Assets," IEEE Spectrum, January 2001, p. 84]. ...DDI will still scrub the gas before it goes to the microturbines by passing it through iron-impregnated wood chips...

If the biogas is not scrubbed, the sulfur could precipitate out of the exhaust as an acid, a danger for surrounding equipment as well as the farm's 12 000 m2 of aluminum roofs.

via Waste Not, Pollute Not

Well there you have it! Biogas Dangers never imagined!

Anaerobic Digestion Community Website