Sunday, January 19, 2020

Anaerobic Digestion vs Landfill Which is Best

Assessing the advantages of anaerobic digestion vs landfill as a means of disposing organic waste is an important step.

Businesses need to know for sure that if they move from landfill to anaerobic digestion as the means of disposal of their waste there are not known issues which may prove a risk to the reputation of their organisation.

Image illustrates an AD plant illustrating the article on Anaerobic digestion vs Landfill
Members of the public who spend a lot of their time each day separating their kitchen waste, putting it in a caddie and leaving their scraps out for their council's kerbside collection, also need to know that their efforts are worthwhile.

If you are one of those, read-on because we are about to answer your question! If not, and your motive for seeking this article out is other than mentioned above, keep reading as well! The answer is most likely, also here.

Anaerobic Digestion vs Landfill for Waste Disposal

The starting point for the comparison of Anaerobic Digestion vs Landfill is the assumption that an individual/ organisation has organic waste (biological waste or waste biomass) which needs to be disposed of responsibly. Many people simply wish to "get rid of" their waste as cheaply as possible, but by asking this question, it implies that the enquirer accepts that they have a social responsibility to use the best method.

In this article our assumption is that the "best" method of waste disposal (getting rubbish taken away and out of sight) also includes doing it in a sustainable way from the point of view of avoiding as far as possible:

  • causing a risk of environmental harm to the local environment, and
  • minimising carbon emissions in the light of climate change as witnessed by rising temperatures and extreme weather conditions (as occurred in 2019 and to a lesser extent in the preceding years).

Now, let's consider both anaerobic digestion and landfill as waste disposal methods separately.

Having clarified both as waste management techniques we will provide our comparison of these two very different methods, and give our opinion on which is "best".

First, it is necessary to understand the basics of the anaerobic digestion process:

What Happens to Waste During Anaerobic Digestion

Organic waste which can range from inedible food (food waste) to cow manure, out-of-specification food crops to chicken feathers, can all be suitable for disposal by fermentation in the anaerobic digestion (AD) process. The AD process is simply controlled "rotting" (decomposition) without air.

This incidentally also produces an energy output in the from of "biogas". The biogas is sold for profit, or used to make electricity which when not needed to power the plant, is also sold.

This provides a very important environmental benefit because biogas is a renewable energy source. In fact, a well-run AD facility can be a net-negative carbon emitter, putting back carbon into the soil each year where it will stay, and replacing fossil fuel use. In other words, anaerobic digestion can ultimately help reverse greenhouse gas emissions.

Disposal of the waste is also achieved during anaerobic digestion. Some of the waste mass (carbon and hydrogen (CH4) is converted to methane during the process. This is called "mass destruction" in the waste industry. What remains is converted to simpler substances after the cell walls of plant matter are ruptured.

These simpler (shorter chain molecules) are the building blocks of biology. Unsurprisingly, they can be used as a natural fertiliser (subject to human health safety controls) and soil improver.

In addition to liquid fertiliser, anaerobic digestion process output (digestate) occurs in the form of a solid phase. The digester output of solids comprises fibres, husks etc., and a small proportion of inert material, plus unwanted contaminants such as plastic materials.

Subject to compliance with regulatory removal of unwanted contaminants, and public health related regulatory compliance, the ultimate destination (disposal point) for anaerobic digestion residues is onto land for a beneficial use (e.g. a fertiliser). When this is coupled with an agricultural spreading plan to avoid build-up of certain chemicals, this form of disposal can continue for an indefinite period on the same land. Thus waste disposal via anaerobic digestion is classed as a long-term sustainable form of waste disposal.

Recycling takes place on two levels during anaerobic digestion. The production of biogas which recycles energy as the first level. The remaining liquid and fibre output (digestate) recycles the fertilising materials which new crops need to grow healthily.

What Happens to Waste When Placed in a Landfill

Tequask [CC BY-SA]
Modern landfills are designed to be lined and capped and to subject the environment to the minimum actual harm, and risk of harm through pollution of their surroundings, as possible.

Waste is usually pre-sorted for recyclable materials before it is dumped in a landfill and the organic content may be removed, but this is rare. In general, only the valuable materials in solid waste, such as metals (e.g. iron, copper, tin etc), paper, and glass are removed before tipping in a landfill.

Paradoxically, this practise also creates conditions in the waste where uncontrolled anaerobic digestion occurs, producing landfill gas (a biogas - but not so clean as AD plant biogas). The biogas can, and usually is collected and used. But the proportion of the biogas collected over the long lifetime in which an old landfill produces biogas, is seldom above 60%.

The nutrients that remain, far from being usable as a fertiliser contain many contaminants which for a well-controlled landfill may not be inherently toxic in themselves are at very high strengths. The high strength "leachate" results in a highly toxic effect should the ever be a leak.

Of course, there will be leaks to all landfill membrane containment systems. Nothing lasts forever, and even if the materials used to hold the leachate inside didn't deteriorate geological changes will occur. Through erosion, earthquakes, and other effects the earth's crust never stops being modified.

So, those are the fates of waste materials when subjected to the anaerobic digestion process, and for all rubbish 'disposed" to landfill.

A comparison of Anaerobic Digestion vs Landfill

The important differences between anaerobic digestion and landfill follow:

1. "Treatment" versus "Hiding Out of Sight"

Anaerobic digestion treats waste. It converts the waste into a form which can be used again. It is a form of recycling in which the original chemicals in plant matter (organic chemicals as well as mineral-based compounds) are decomposed and become available to provide for re-growth of a next generation of plants.

Landfill, while a form of slow anaerobic digestion does occur within them, is mostly a form of entombment. The trash is effectively hidden under a restored surface such as grassland or a park. Where it works well, our old possessions may well still be there for future archaeologists to dig-up in 2,000 or even 3,000 years time.

Where landfill doesn't work well, the linings will cease to contain the leachate, and the landfill gas will escape. The leachate will contaminate the subterranean water and render wells undrinkable for future generations. The gas will cause a risk of explosions as it escapes, and when it gets into the atmosphere continue to cause even further global warming than current predictions allow for.

2. The Need for Ever More Space for Landfills

The anaerobic digestion process needs no more space than the footprint of the tanks and equipment, plus short-term storage bays for the incoming waste. There is no additional land needed no matter how long the biogas facility will continue to operate.

Landfill constantly fills up huge void spaces. Land area is finite, and suitable land for landfilling only a small proportion of all available land. As cities become larger and are intensively developed waste has to be transported ever further out to where new landfill space can be created. Costs rise while this is possible, but in some countries they are already unable to find suitable land for new landfills.

3. The Need for Ever More Resources to Replace Materials Placed in Landfills

Anaerobic digestion is a mainly resource neutral process, and is based upon recycling the same mineral and organic resources time and again with no end-point.

The consequence of landfilling is the need to constantly replenish the materials placed in them, with new materials constantly to be won from the ground quarries multiply. But mineral resources are finite. They become progressively harder to find, and need more energy to extract the lower grade minerals.

Just as far the landfills themselves the available land will inevitably run out.

Anaerobic Digestion vs Landfill - The Verdict

Anaerobic digestion technology is not yet fully developed and far from perfect as a recycling method. It is in general more expensive than the average cost globally of landfilling, especially if landfill taxation is allowed for. There are limitations on for how long individual fields can be fertilised from digestate in any period of time, before it is necessary to move on. Care is needed to prevent air pollution during spreading, and there are health risks if basic safeguards are not applied.

Nevertheless, in the long-term the anaerobic digestion method is one which shows no reason why it should not be applied for thousands of years. It needs no energy to fuel it as it is easily capable of providing its own power and much more besides. Environmental damage from anaerobic digestion is limited to such errors as digester tank leakage, or an explosion of the stored methane. Such damage can be severe at the time and costly. However, costs for AD plant repair would generally be in the range $100k to $2million.

In comparison, landfill cannot be sustained for long, and in some of the largest and oldest urban nations it is already not a viable option for reasons already described, such as space and land availability. It requires a lot of fuel to develop and fill landfills, much of the biogas if used only pays back on the embedded carbon emissions from its construction. What landfilling has been completed also provides a future threat to the local environment which can be very costly for future generations. Clean up costs for landfills range from $500k to $billions, as has occurred already in the United States (Clean-Up Superfund).

Therefore, on the grounds of sustainability and risk of future environmental damage anaerobic digestion is best.

On the grounds of reputation risk to businesses deciding to change their organic (biological) waste disposal from landfill to an AD plant, each will make their own decisions. Individual biogas plants will inevitably fail, but in principal the risk of that is offset by awarding the contract to a well-established and well-run biogas organisation.

Friday, December 27, 2019

Cow Dung and Anaerobic Digestion

To get biogas, farmers are creating their own, by using cow dung and building a bio-digester. 
The end products are also a good source of fertilizer for crops. Making their own biogas saves hundreds of US$ per year in fuel costs for fuel that is used to run small water pumps.


A biogas digester plant relies on bacterial decomposition of biomass, waste material which is biological in origin, ranging from kitchen scraps to cow dung. 
As anyone who has walked past a poorly maintained outhouse or compost pile is aware, when anaerobic conditions develop in a collection of biomass, they attract bacterial organisms which emit a number of distinctive gases.
These are most notably methane, which is produced in the process of digestion. These gases are usually viewed as a symptom of inefficiency and they are vented away for disposal, but they can actually be very useful.

Why is Cow Dung Often Used to Start Up Biogas Digesters?

Most biogas digesters use cow dung to produce biogas. There are many other organic materials as mentioned above that can be used to produce biogas. Like left over food scraps, vegetation etc.
For this reason, cow dung is commonly used to start the process of biogas production. You can change the organic material to be used to produce biogas after the production has been kicked off by cow dung.

How Much Biogas is Produced?

A one-cubic-meter digester, primed with cow dung to provide bacteria, can convert the waste generated by a four-person family into enough gas to cook all its meals and provide sludge for fertilizer. 
A model this size costs about $425 but many testimonials suggest that such a facility will pay for itself in energy savings in less than two years. 
Admittedly, that's still a high price for most Indians, even though the government recently agreed to subsidize about a third of the cost for these family-sized units.
For the equipment to produce gas, the digester is filled halfway with bio-degradable materials, like cow dung mixed with water in equal ratio. It is then refilled with smaller amount every day, or at intervals no longer than to 2 weeks. The equipment can start producing gas after seven days.

Gober Gas

Gober gas (also spelled gobar gas, from the Urdu, Punjabi and Hindi word gober for cow dung) is biogas generated from cow dung. 
A gober gas plant is an airtight circular pit made of concrete with a pipe connection. First, manure is dumped in the pit. Then, water or wastewater is added to the manure and the concoction is sealed in the airtight concrete pit with a gas pipe leading to stove unit in the kitchen serving as the only egress for gas. When the control valve on the gas pipe is opened the biogas is combusted for cooking in a largely odourless and smokeless manner.
Cow Dung graphics and explanation.

The image above shows the fixed dome digester design often used for cow dung, chicken manure and human excreta. 

Fixed Dome Digesters

Fixed dome plants were chosen because they can last for over fifty years and they are easily insulated and scum fosrmation is less due to the digester slurry that is displaced (pushed out) by incoming feed (influent). 
A fixed dome digester is an underground biogas digester lined with brick, with a dome-shaped cover made from concrete. The cover is fixed and held in place with earth piled over the top to resist the pressure of the gas inside. A second pit, the slurry reservoir, is built above and to the side of the digester.

Final  Size of the Biogas Plant

The size of the biogas plant is to be decided based on availability of raw material. It is generally said that, average cattle yield is about 10 kg dung per day. For eg. the average gas production from dung may be taken as 40 lit/kg. of fresh dung. The total dung required for production of 3 m3 biogas is 3/0.04= 75 kgs. Hence, a minimum of 4 cattle is required to generate the required quantity of cow dung.
A one-cubic-meter digester, primed with cow dung to provide bacteria, can convert the waste generated by a four-person family into enough gas to cook all its meals and provide sludge for fertilizer. A model this size costs about $425 but will pay for itself in energy savings in less than two years. That's still a high price for most Indians, even though the government recently agreed to subsidize about a third of the cost for these family-sized units.

Friday, November 08, 2019

Anaerobic Digestion in Germany - Deutschland Biogas Industry Outlook

The Anaerobic digestion market throughout the years has actually encountered varied applications throughout agriculture, metropolitan, and food & drink sectors.

Business owners and farmers across the region have in reality taken on these technologies to set up a foreseeable earnings stream and power resource with the purpose being to decrease dependence on mineral plant foods and fossil gas.

In addition, the food as well as drink market has actually welcomed the modern technology to refine its residue in an ecological acceptable manner and preventing landfill cost.

The European Union identifies the demand to support organisations to introduce.

EISENMANN is an instance of an effective German biogas tools making company. It is also well recognized as one of the leading global distributors of general ending up technology, product flow automation, environmental modern technology including Biogas in addition to ceramics and also thermal handling innovation.

Products of this company include blowers, exhausters, vacuum pumps and compressors looked for all sorts of gasses.

Image shows Anaerobic Digestion in Germany.
One good practice to study is the Green Gas Initiative in Europe. This is a joint commitment among the gas transmission system operators of Belgium, Denmark, France, Germany, the Netherlands, Sweden and Switzerland to "green" the gas grid through biomethane integration.

Most of the current biogas production is currently located in Germany, which hosts 9,500 or so biogas plants, more than half the total number of installations currently in operation across the EU.

But the industry has big ambitions for the future, with France and Italy now seen as the new European leaders. A study commissioned by Gas for Climate, an industry consortium, claims production in Europe could skyrocket to 98 bcm of biomethane by 2050 – a 4,800% increase on current levels. via

6 Ways to Get Anaerobic Digestion Finance - Sources of Funds for Biogas ...

Anaerobic Digestion Finance Mechanisms Pros and Cons

Keep watching and in under 5 minutes you will learn from this video 6 popular ways to arrange for your Anaerobic Digestion project finance, with the main advantages of each method and disadvantages.

The funding approaches we are about to describe, are not mutually exclusive.; a mixture of different approaches may be adopted.

Funding Instrument 1 - Private Equity Financing

This involves an investor who is willing to fund all or a portion of the project in return for a share of project ownership.

Private equity financing has the advantages of lower transaction costs and usually the ability to move ahead faster than with other financing approaches.
However, private equity financing can be more expensive.

Funding Instrument 2 - Project Finance

Project Finance is a popular method for financing private power projects in which lenders look to a project’s projected revenues, rather than the assets of the developer, to ensure repayment.

This approach allows developers to retain ownership control of the project while obtaining financing. Disadvantages of project finance are high transaction costs and a lender’s high minimum investment threshold.

Funding Instrument 3 - Municipal Bond Financing

Municipal Bond Financing is applicable for municipal projects such as municipally owned landfills and municipal end users. It may also be possible to use this bond type to fund landfill gas extraction and utilization projects.

This involves the local government issuing tax-preferred bonds to finance the Anaerobic Digestion, or LFG energy project. This approach (if available) is the most cost-effective way to finance a project because the interest rate is low and the terms can often be structured for long repayment periods.

However, municipalities can face barriers to issuing bonds, and therefore it may be better to look at:

Funding Instrument 4 - Direct Municipal Funding

Image is a thumbnail illustrating anaerobic digestion finance options.
Direct Municipal Funding, possibly the lowest-cost financing available other than Municipal Bonds, uses the operating budget of the city, county, landfill authority or other municipal government to fund the project.

This approach eliminates the need to obtain outside financing or project partners, and it avoids delays caused by the extensive project evaluations usually required by lenders or partners.

However, many municipalities may not have a budget that is sufficient to finance a project, or may have many projects competing for scarce resources.

Delays and complications may also arise if public approval is required.

Funding Instrument 5 - Lease Financing

Lease Financing provides a means for the project owner or operator to lease all or part of the energy project assets.

This arrangement usually allows the transfer of tax benefits or credits to an entity that can best make use of them.

Lease arrangements can allow for the user to purchase the assets or extend the lease when the term of the lease has been fulfilled.

The benefit of lease financing is that it frees up capital funds of the owner or operator but allowing them control of the project.

The disadvantages include complex accounting and liability issues and loss of tax benefits to the project owner or operator.

Finally, there may be the possibility of grant programs for some anaerobic digestion and renewable energy projects:

Funding Instrument 6 - Grant Programs

Grant Programs, offered by many federal and state programs may provide funding for LFG, biogas and anaerobic digestion energy projects.

Read our article at:

Tuesday, October 29, 2019

UK General Election December 2019 - Do This or Fail to Match 2017 Government Green Pledges A Challenge to the New Government

The news is just breaking that parliament is set to agree a UK General Election on 12 December 2019. The new government must act as below, or fail to match the green pledges already made by the 2017 Conservative Government.

So, Labour, Conservative, or Liberal politicians you must match these green pledges or better them on sustainable renewable energy and the environment! That's our challenge to the New Government. And, in view of the climate change imperative to act now, this is much more important than ever before!

ABDA issued the following PR on 23 October before parliament voted to suspend the Fixed Term Parliament Act today (30 October 2019).

"ADBA’s vision is to see the full potential of the UK AD industry realised so it can help the UK achieve its emissions targets and other policy goals, creating a truly circular economy."
Press Release:

Anaerobic digestion trade association submits proposals to Government ahead of the Budget

Letter to Chancellor highlights the industry's potential towards achieving the Government's Net Zero emissions target and the impact of uncertainty on the sector.

Priorities set out by ADBA include better cross-departmental working to ensure coordinated policy and support towards the implementation of separate food waste collections, a new funding system and dedicated Research & Innovation infrastructure for the industry.
Charlotte Morton of ADBA
UK AD industry has potential to reduce UK greenhouse gases emissions by 5%.

With the UK needing to show leadership on ultra low carbon technologies as President of the 2020 UN Framework Convention for Climate Change Conference of Parties (COP26), the Anaerobic Digestion and Bioresources Association (ADBA) has written to Chancellor Sajid Javid ahead of the next Budget announcement, setting out the industry's views on the policies needed to stimulate growth of the anaerobic digestion (AD) sector and fulfil its potential to reduce some of the hardest-to-decarbonise emissions.  

Currently, AD is predominantly recognised for its role in generating green energy.

But AD also prevents methane emissions from organic wastes left to break down in landfill – and there is a huge untapped potential for methane capture, use and conversion with millions of tonnes of organic wastes from farming, food and sewage currently not being treated through AD.
In addition, AD treatment of organics recovers nutrients to fertilise depleted soils and improve their ability to sequester carbon.

The Treasury has been tasked with coordinating government efforts to achieve Net Zero emissions by 2050.  The AD has the potential to cut UK emissions by 5% across multiple sectors and therefore needs policy incentives applied across multiple Government departments (namely BEIS, Treasury, DEFRA, and Transport) to operate effectively.   Good cross-departmental policy coordination is therefore essential to enable the industry to grow and achieve widespread emission abatement.  This is a key ask from ADBA, which also lists the following priorities:

The Government must provide clear financial parameters to Local Authorities (LAs) to implement the mandatory separate food waste collections by 2023 stated in the Resources & Waste Strategy – which features a clear preference for inedible food waste to be recycled through AD.

It is vital that LAs are fully supported with set up costs that include funding the development of infrastructure to enable LAs to do so. Government must clarify its financial support as a matter of urgency, especially as around 70 LAs will be signing new waste contracts in the time period leading to the separate food waste collections implementation deadline.

The Budget must commit to an interim pot of funding for biomethane plant deployment similar to the Renewable Heat Incentive, which is due to come to an end in March 2021, while a future funding mechanism is developed (the Feed- In-Tariff has already closed, the lack of a floor price makes the Renewable Transport Fuels Obligation an unstable alternative to support biomethane plant deployment, Contracts-for-Difference support the larger AD plants whilst many in the sector are small, and the Smart Export Guarantee does not provide price certainty, or consider the wider, non-energy benefits of AD).

It is critical that the Budget commits additional support for AD for 2021 and beyond.

The Government must support AD innovation to make it financially autonomous. Enclosed in ADBA's letter to the Chancellor was the trade association's proposal for a virtual Centre for Anaerobic Biotechnology and Bioresources Research (CABB) to develop new waste management technologies, that would not only boost British exports, but also transform the sector’s performance and eliminate the need for subsidies in the future.  CABB's objective is to transform AD into a low-cost, multifunctional biotechnology and a key ingredient in developing integrated processes to deliver future energy and resources provision.

ADBA's Chief Executive Charlotte Morton said:
"As a result of enjoying consistent policy and funding support, the wind and solar industries have become extremely cost-effective and are now established as part of the renewable energy mix. AD should be given the same fair treatment, to put the sector on the ‘glide path’ to no subsidy, as costs come down and innovation drives cost savings across the industry.
The UK AD sector has grown by over 350% over the last ten years and established itself as a world leader with UK companies exporting biogas-related expertise and equipment. However, the current timeline for the Greening the Gas Grid consultation is unlikely to provide the urgent continuity necessary to stimulate further industry growth. 
The sector's progress has already effectively stalled due to the lack of policy certainty, and there is a real risk of losing expertise if there is an ongoing gap in policy provision. Meanwhile, with CABB, we could supercharge our industry and put it at the cutting edge of agricultural science.
We await the Budget next month with interest and are continuing our discussions with the Treasury and BEIS on our proposals in advance of its publication."

- ENDS -

Monday, October 21, 2019

Advantages of Biofuel: The New Sustainable Oil-Fields Of Tomorrow

Biofuels play a major part in the renewable energy strategy of Denmark.

Denmark is using biofuel to achieve its target of using 100% renewable energy for all energy uses by 2050. In this, biofuels provide a large share of he future energy sources in Denmark. Especially when considering all sectors of energy demand in conjunction with Denmark's highly developed renewable energy resources.

The main sources of biofuels in Denmark include:
  • wood and wood products
  • energy from waste straw
  • biogas biodiesel and bioethanol.

Biofuels have the potential to provide environmental and economic benefits, but they must be carefully managed to ensure that they are truly sustainable resources.

There is the potential for economic and environmental damage if biofuels are not used responsibly. Biofuel use in Europe must be certified by the EU Commission before biofuels can be recorded as sustainable resources, and used for national renewable energy targets.

The oil shocks of the 1970s severely impacted Denmark as about 90% of its energy use then came from oil. The majority of that oil was imported. So, the government was thus compelled to rethink its energy portfolio.

It shifted the focus of its energy plans as a result biomass for bioenergy started being incentivized. Even way back then, it was promoted as a renewable energy source, and an alternative to fossil fuels. Denmark's aim was to reduce the oil dependency and to secure energy supplies.

That's an objective that has remained relevant in the progression of the country's energy policy to this day.

The prospect of the creation of new jobs in the utilization of waste products also factored into Denmark's decision to start using biomass, consequently the use of biomass in the Danish energy system has continuously grown.

In the last decade bio energy consumption in Denmark has nearly doubled, increasing by more than a factor of 12 between 1970 and present day.

Over this period biomass has been predominantly used in the form of waste straw and wood.

Image shows one advantage of biofuel as an energy source for transport.
Currently Denmark is striving to create an energy system by 2050 that is free of all fossil energy. so, bioenergy will likely play a key role in order to achieve this goal.

In addition, Denmark has since 1993 been increasing its development of large-scale combined heat and power plants.

CHP plants combust biomass and do it in a way that has achieved continuous technological improvements. Many improvements have been achieved over the past 20 years.

The Danish strategy to reduce emissions has also included retrofitting older coal-fired plants to make them biomass-fired.

They are investing heavily into research development and demonstration (RD&D) for converting agricultural residues into second generation 2g bio ethanol.

Bio ethanol which is then blended with gasoline for the transportation sector.

RD&D activities are also in place for biodiesel for shipping and Road Transport in agreement with the European Environment Agency, scientific committee.

Denmark considers environmental sustainability as a key component of its strategy to incorporate a greater share of biofuels into its energy portfolio. As such, it does not consider biomass produced from existent forests as carbon neutral. But, it counts waste.

Biomass has doubled in output towards its renewable energy target, thus favoring biomass grown on marginal land or sourced from residues. This way the country is able to ensure that it benefits from incorporating a larger share of biomass into its energy system.

Biomass sourced from plantations that have been converted from natural forest land then generates a net carbon benefit over fossil fuels.

Denmark's guidelines for utilising biomass for energy and transportation strive to ensure both environmental sustainability and efficiency aspects as a member state of the European Union (EU). Denmark is working under commitments from its directives which set targets for the amount of renewable energy within the national profiles including biofuels.

It is following the EU legislation. For example its renewable energy use should reach 100% by 2020.

However, Denmark has been highly proactive and ambitious in the targets it has set for its renewable energy in greenhouse gas emissions reduction. Such as aiming for 100% renewable energy by 2050.

Source: Wikipedia article.

Monday, October 14, 2019

Biogas Plants Must Comply with these 4 UK Regulations - PPC Compliance for Anaerobi...

This presentation contains images that were used under a Creative Commons License. Click here to see the full list of images and attributions:

4 Essential UK Regulations All Biogas Plant Operators Must Observe

All anaerobic digestion plant operators in the UK must comply with the regulations concerning environmental protection, animal by-products, duty of care, health and safety and waste handling!

Keep reading! Please give us a little bit of your valuable time, and in 5 to 10 short minutes we will explain our list of 4 essential UK regulations all biogas plants must comply with.

Regulation 1. Environmental Permitting

Environmental Permitting (EP) is a scheme in England and Wales, for regulating business activities that could have an impact on the environment and human health. AD plant operators must obtain a permit, or an exemption to operate and to spread digestate, and show that you are competent to operate the plant.

There are three levels of permitting, a number of activities that entitle operators to an exemption.:

Exemptions are available for small scale biogas digesters which are classified as non-waste facilities, but you are still required to register with the Environment Agency and provide some technical information, although no charges apply.

If your activity is not exempt, the next step in rising permit complexity is the need for a Standard Permit.

These are simplified permits used for plants which fit within a number of pre-defined standard rules, including throughput, output and nature of material being digested and for this fixed charges apply.

If a biogas plant's method of operation doesn't fall within the rules they don't allow the adoption of a Standard Permit.

The next step-up in complexity, and charges, is a "Bespoke Permit", (in this instance variable charges apply).

This process is more costly and time consuming, but provides greater coverage and flexibility in plant operations. Permits may also be required for Spreading Digestate.

Designing an AD Plant which is shown to comply with the PAS 110 Quality Protocol can become important to reduce the degree of regulatory involvement.

Material that has been processed to PAS 110 and Quality Protocol standards is no longer regarded as a waste.

However, to spread waste material (prior to achieving PAS 110 accreditation) to agricultural and non-agricultural land to confer benefit or ecological improvement, you will still have to apply for a permit or register for an exemption.

If you do not fit the criteria for an exemption there is a Standard Rule Permit, for spreading waste material to land, and a fee will be charged.

Seeding new AD Plants may also require a permit or exemption, during plant start-up.

Regulation 2. Animal By-Products Regulations

Animal by-products (ABPs) are animal carcasses, parts of carcasses or products of animal origin that are not intended for human consumption. The Animal By-Products Regulations (ABPR) permit the treatment in approved composting and biogas premises of low-risk (category 3) ABPs and catering waste which contains meat or which comes from a premises handling meat.

High risk (Category 2) ABPs such as manure and digestive tract content, cannot be used as feedstock in biogas plants, except, after the output has been treated to special pressure-rendering standards.

Further information is available from the Animal and Plant Health Agency (A.P.H.A.).

Regulation 3. Duty of Care

The duty of care is a law which says you must take all reasonable steps to keep waste safe. You have a legal responsibility to ensure that you produce, store, transport and dispose of waste without harming the environment. Duty of care law is available at the UK Government Defra and Environment Agency websites.

Regulation 4. Health and Safety at Work Regulations

Anaerobic digestion can be regarded as a chemical process with all the associated risks: flammable atmospheres, fire and explosion, toxic gases, confined spaces, asphyxiation, pressure systems, COSHH, etc.

In addition, it also incorporates gas handling and gas storage.

Therefore, it is essential that thorough hazard and risk assessments are carried out at each stage of any biogas plant project from design to installation to commissioning to implementation and operation.

Thanks for reading this and we hope you found this article useful.

At IPPTS associates consultants; we offer our services to help you comply with all of these regulations, provided that you have a budget for our work:

Sunday, October 13, 2019

Tipos de planta de biogás - Qué sucede en una planta de biogás

Tipos de planta de biogás - Qué sucede en una planta de biogás Explicación de la digestión anaerobia.

5 tipos de plantas de biogás: los diseños de plantas DA más comunes en los Estados Unidos.

Siga buscando nuestros 5 mejores tipos de diseño de plantas de digestión anaeróbica en los Estados Unidos., Enumerados en orden de popularidad.

Tipo 1. Laguna anaeróbica cubierta

En un diseño de laguna anaeróbica cubierta, el metano se recupera y se canaliza al dispositivo de combustión desde una laguna después de que se recoge debajo de una cubierta flexible.

Aquí hay un diagrama de una laguna anaerobia cubierta que muestra 2 células.

La primera celda retiene el influente del digestor y atrapa el biogás y la segunda celda recoge el efluente del digestor.

Algunos sistemas usan una sola celda, como se muestra aquí, para la digestión y el almacenamiento combinados, y otros tienen múltiples celdas.

Aquí hay otra fotografía de este tipo de diseño de planta DA.

Tipo 2. Digestor de flujo de enchufe

Los digestores de flujo de tapón se utilizan principalmente en operaciones de lácteos que recolectan estiércol mediante raspado.

Los sistemas de flujo de tapón se han utilizado en una amplia variedad de operaciones, ya que pueden tolerar una gama más amplia de concentraciones de sólidos.

Aquí hay un diagrama de un digestor de flujo de tapón que muestra el influente del digestor entrando y fluyendo a través del digestor, con el biogás siendo capturado y almacenado debajo de una cubierta.

Este ejemplo muestra otro digestor de flujo de tapón con una cubierta de membrana de plástico flexible.

Este ejemplo muestra un digestor de flujo de tapón con una cubierta rígida.

Tipo 3. Mezcla completa de plantas de biogás

También se denominan CSR o reactores de agitación continua.

Los digestores completamente mezclados están diseñados con un tanque cerrado y calentado con un sistema mecánico, hidráulico o de mezcla de gases.

Tipos de planta de biogás
Los digestores de mezcla completa funcionan mejor cuando hay una cierta dilución del estiércol excretado con agua (por ejemplo, aguas residuales del centro de ordeño).

Aquí hay un diagrama de un digestor mixto completo, que ilustra el proceso de agregar estiércol al digestor; mezclar, calentar y almacenar el biogás dentro del digestor; y extraer el efluente resultante.

Aquí hay una foto de dos tanques de digestor de mezcla completa con un agitador montado en la pared.

Aquí hay una foto de un mezclador montado externamente, en una estructura de soporte.

¡Ya estamos a la mitad de este video! ¡Sigue mirando! ¡Es posible que no haya oído hablar de estos tipos de plantas de biogás antes!

Tipo 4. Digestores por lotes.

Un digestor por lotes es la forma más simple de digestión, donde el estiércol se agrega al reactor al comienzo del proceso como un lote. El reactor se llena y el reactor permanece cerrado durante la duración del proceso.

Tipo 5. Reactores combinados inducidos.

Estos también se conocen como UASBR (Reactores de flujo de lodo anaeróbico ascendente). Estos son digestores en los que se desarrolla una capa de lodo y retiene las bacterias anaerobias, proporcionando un ambiente rico en bacterias a través del cual debe pasar la materia prima.

Fuente: sitio web de US Agstar.


This presentation contains images that were used under a Creative Commons License. Click here to see the full list of images and attributions:


Watch this video on YouTube here:


Don't forget to check out our YouTube Channel:

and click the link below to subscribe to our channel and get informed when we add new content: