Optimization of semi-continuous anaerobic digestion of sugarcane straw co- digested with filter cake: Effects of macronutrients supplementation on conversion kinetics


https://www.hindawi.com/journals/ijce/2018/9351848/

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A Waste Management Solution for 430+ Customer Partners Worldwide.

We are PlanET Biogas Global GmbH based in Vreden, Germany.

Our company eliminate the need for ever increasing organic waste landfill, aerobic lagoons, and chemical treatment to manage and control waste. We turn waste into fuel resources to generate power. Recommend ways to start Waste-to-Energy (W2E) Projects.

We provide a free-of-charge simple project feasibilty, sustainability, and ROI study based on given waste data. Our Biogas/Biomethane Design Engineers will analyze, quantify, qualify, assess potentials of a given waste data. If interested to have one for your particular application, kindly completely fill up questionnaire found on the link below:

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

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For interested non-sugar industry company, do reply on the kind of industry you are in and we will email corresponding questionnaire that you can fill up.

Looking forward to serve you.

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

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Biogas Benefits Essential as Climate Change Carbon Hits Record High and Summer Heat Peaks


https://blog.anaerobic-digestion.com/biogas-benefits-climate-change-peaks-2017/

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A Waste Management Solution for 430+ Customer Partners Worldwide.

We are PlanET Biogas Global GmbH based in Vreden, Germany.

Our company eliminate the need for ever increasing organic waste landfill, aerobic lagoons, and chemical treatment to manage and control waste. We turn waste into fuel resources to generate power. Recommend ways to start Waste-to-Energy (W2E) Projects.

We provide a free-of-charge simple project feasibilty, sustainability, and ROI study based on given waste data. Our Biogas/Biomethane Design Engineers will analyze, quantify, qualify, assess potentials of a given waste data. If interested to have one for your particular application, kindly completely fill up questionnaire found on the link below:

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

A Project Budgetary Concept Proposal (BCP) and a Consultancy Service Proposal (CSP) will be submitted for your consideration if the W2E project potential you have is feasible, sustainable, and have less than 5 years ROI. It will be a nice company cost saving and additional profit project to implement.

For interested non-sugar industry company, do reply on the kind of industry you are in and we will email corresponding questionnaire that you can fill up.

Looking forward to serve you.

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

Biomethane, the Spanish case


http://gasnam.es/wp-content/uploads/2015/04/1._Biomethane_the_Spanish_case_v3.pdf

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A Waste Management Solution for 430+ Customer Partners Worldwide.

Greetings!

We are PlanET Biogas Global GmbH based in Vreden, Germany.

Our company eliminate the need for ever increasing organic waste landfill, aerobic lagoons, and chemical treatment to manage and control waste. We turn waste into fuel resources to generate power. Recommend ways to start Waste-to-Energy (W2E) Projects.

We provide a free-of-charge simple project feasibilty, sustainability, and ROI study based on given waste data. Our Biogas/Biomethane Design Engineers will analyze, quantify, qualify, assess potentials of a given waste data. If interested to have one for your particular application, kindly completely fill up questionnaire found on the link below:

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

A Project Budgetary Concept Proposal (BCP) and a Consultancy Service Proposal (CSP) will be submitted for your consideration if the W2E project potential you have is feasible, sustainable, and have less than 5 years ROI. It will be a nice company cost saving and additional profit project to implement.

For interested non-sugar industry company, do reply on the kind of industry you are in and we will email corresponding questionnaire that you can fill up.

Looking forward to serve you.

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

Biogas from Palm Oil Mill Effluent (POME): Opportunities and challenges from Malaysia’s perspective


https://www.researchgate.net/profile/Kit_Ling_Chin/publication/249963577_Biogas_from_Palm_Oil_Mill_Effluent_POME_Opportunities_and_challenges_from_Malaysia’s_perspective/links/5b29e2bd4585150c633fad2d/Biogas-from-Palm-Oil-Mill-Effluent-POME-Opportunities-and-challenges-from-Malaysias-perspective.pdf

Biodigester Global Case Studies


http://www.build-a-biogas-plant.com/PDF/D_Lab_Waste_Biodigester_Case_Studies_Report.pdf

PROFITABLE SWEET CORN: P118,920 Profit From 3 Kg Seeds Planted On Half Hectare


https://www.zacsarian.com/profitable-sweet-corn-p118920-profit-from-3-kg-seeds-planted-on-half-hectare/

Green Gas. The Opportunity for Britain.


https://www.ecotricity.co.uk/content/download/397/file/green-gas-report.pdf

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We are PlanET Biogas Global GmbH. We have designed, engineered, and constructed over 430 biogas and biomethane plants all over the world. We can help you quantify, qualify, and harness the potentials of ALL your organic waste.

Biogas and Biomethane. Turning waste into resources.

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

Gas From Grass Could Be An Eco-Friendly Biofuel


https://cleantechnica.com/2018/05/24/gas-from-grass-could-be-an-eco-friendly-bio-fuel/

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More Generated Power from Waste

Advance technology + automation + experience + expertise = Innovation

We can do the following for you:

– Generate more excess power to sell.

– Ceate more business revenue.

– Solve your environmental wastewater problems.

– Manage organic waste stench and storage.

– Extend boiler fuel inventory.

– Start a zero-waste system without really trying.

– Offer leading integrated W2E technology.

– Raise efficiency of power generation system.

We are PlanET Biogas Global GmbH. We have designed, engineered, and constructed over 430 biogas and biomethane plants all over the world. We can help you quantify, qualify, and harness the potentials of ALL your organic waste.

Biogas and Biomethane. Turning waste into resources.

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

BIOGAS PLANT DEVELOPMENT HANDBOOK. PART 4.


9. DIGESTATE MANAGEMENT

As illustrated in the section about Wet Versus Dry Digestion, there are essentially five (5) types of digestate:

Clean liquid digestate

Clean solid digestate

Contaminated liquid digestate

Contaminated solid digestate

Contaminated semi-solid digestate

Only the clean liquid or solid digestates can be directly applied to land without further treatment. These digestates often originate from manure, food waste or pre-treated SSO digesters where there are virtually no contaminants in the feedstock to be digested.

Most of the time, liquid digestate is separated into solid and liquid fractions by using liquid/solid separation technologies.

SOLID FRACTION

As mentioned earlier, clean solid digestate can be applied to land directly.

Contaminated solids coming from a dry digester or a liquid/solid separation equipment will need to be composted to achieve proper dryness for the sieving of contaminants prior to land application.

LIQUID FRACTION

Also mentioned earlier, clean liquid digestate can be applied to land directly.

Contaminated liquids coming from a wet digester or a liquid/solid separation equipment will require proper wastewater treatment such as sedimentation of suspended solids, abatement of COD, BOD and ammonia compounds.

10. BIOGAS PLANT COMPONENTS

SITE

Several aspects need to be studied in the choice of a site:

Dominant wind/Air dispersion

Road access

Proximity to energy grids

Geotechnical

Contamination

Proximity of neighbors

CIVIL WORK

The biogas plant will be equipped with roads, scale, drainage, landscaping, etc.

BUILDINGS

Biogas plants will have one or more building(s) to contain the process and all the human resources operating and maintaining it. These building may require special architectural specifications for aesthetic, comfort and efficiency.

RECEPTION

This is the area of the biogas plant where the feedstock is received. It may be designed to receive several trucks of various sizes. Typically, the reception of material will be indoor, and this is where most of the odor challenges arise. Opening and closing of doors for trucks is typically the main source of odors for a biogas plant.

FEEDSTOCK CONDITIONING

Depending on the technology used, this is where the received material is prepared for feeding into digesters. It may be decontaminated by using technologies such as:

Hydro-pulpers

Separating hammermills

Presses

ANAEROBIC DIGESTION

Central equipment of a biogas plant, the digester is where feedstock is biodegraded by anaerobic bacterias to generate the biogas and digestate.

DIGESTATE TREATMENT

Separation : The liquid digestate may be squeezed to separate the liquid fraction from the solids.

Composting : A biogas plant may be equipped with a composting plant to stabilize or allow the drying and decontamination of the solid fraction of its digestate.

Wastewater treatment: The liquid fraction of the digestate often needs to be treated prior to disposal into nature or into sewage.

ODOUR TREATMENT

Odors generated inside the building need to be controlled (with proper ventilation) and treated prior to rejection into the atmosphere.

BIOGAS HANDLING

The following list includes all the equipment necessary to handle the biogas:

Pipes

Flowmeters

Condensate traps

Storage

Flare

BIOGAS TREATMENT

Equipment necessary to clean the biogas to the proper specifications for the intended application.

BIOGAS UTILIZATION

Equipment that will allow utilization of the biogas or biomethane (RNG) as follows:

Boiler

CHP

Biogas upgrader

Compressor

11. BIOGAS PROJECT ECONOMICS

Biogas plant economics are complex and vary with local market conditions.

REVENUE

Biogas plants can generate several revenues such as:

Treatment fees: Money you receive (or save) for accepting and treating the feedstock. In North America, this represents the majority of the income of the project (60-80%).

Energy sales: Money you receive for selling the biogas energy (20-40% of income). Only in markets with generous feed-in-tariffs will the energy sales constitute the majority of the project income.

Digestate/compost sales: Money you receive (or save) for selling your digestate or compost. Typically, you have to pay to dispose of the digestate or compost.

Carbon credits: Biogas plants do generate carbon credits that can be sold. However, the volume is small, and the validation and certification fees often take the lion’s share of this income.

FINANCING

Biogas plants are financed using equity, debt, subsidies and tax credits.

Municipalities will finance their project with subsidies and debt. Private projects will require significant equity (25%) and energy contracts from solid clients to secure their debt.

OPEX

Operational expenses (OPEX) are typically composed of:

Salaries

Debt service charges

Disposal charges (contaminants, digestate)

Energy (consumed)

Equipment maintenance

Consumables

Taxes

Insurances

CAPEX

Capital expenses (CAPEX) vary greatly between projects.

Municipal projects are the most complex and expensive. Typically, in North America, they cost anywhere between $800-$1500/tonne of annual treatment capacity.

Agricultural projects are the simplest and least expensive. Typically, in North America, they cost anywhere between $4500-8000/kW electrical installed.

12. BIOGAS PROJECT DEVELOPMENT

There exist several critical steps in the realization of a successful biogas project, though project developers tend to focus their effort on determining the best anaerobic digestion technology for their project instead of getting a firm grip on their project fundamentals before anything else.

Biogas plants are large expensive finicky biological systems that require careful planning. In fact, most biogas plant failures are due to poor planning and/or not paying close enough attention to project fundamentals such as feedstock, energy utilization, digestate management, and financing.

STUDIES & PRELIMINARY ENGINEERING

A lot of work must be put into establishing the project fundamentals (studies).

Establishing expected feedstock collection methods (trucks, bins, routes, etc.), quantity, quality and overall logistics (collection contracts, transfer stations, hours of reception, etc.) often require significant studies and planning. One must not underestimate the effort necessary to understand how much, when, and in what state the organic waste will get to the biogas plant.

Finding a proper site for a biogas plant also requires significant effort. The site needs to meet proper zoning, and environmental regulations (proximity to houses, rivers, wells, etc.). The site must also be easily accessible by road for the feedstock to come in, and the digestate to come out without causing too much traffic nuisance to the neighborhood. Finally, the site must be close an energy grid (gas or electrical) in order for the biogas energy to be exported efficiently.

Digestate management must be studied carefully since the disposal of digestate is often the largest operational cost of a biogas plant. All possible avenues of disposal, transformation or treatment must be taken into consideration to ensure that the final strategy for digestate management is the most efficient. Otherwise, the biogas plant economics will be less than optimal.

Once the fundamentals are established, a concept will be drawn and priced to get a project budget.

Beyond this initial engineering concept, further studies and analysis are often required as follows:

Site contamination (soil, buildings, etc.)

Risks analysis

Value analysis

Applicable codes, rules and regulations

Timeline estimation

Proper preliminary engineering is essential to develop a viable business case that will justify the significant financing required to realize the biogas project.

DESIGN

Detailed engineering of a biogas project is composed of several disciplines working in close collaboration such as:

Project Management

To ensure that all engineering disciplines are working together closely to efficiently deliver an optimal design.

Process Engineering

To determine the processes required for feedstock conditioning, anaerobic digestion, gas treatment, digestate treatment, odor management, etc.

Mechanical Engineering

To deal with all aspect of material handling: solid waste reception & conveying, liquid pumping, gas compression, etc.

Electrical Engineering

To deal with all aspects of power supply and automation (sensors, PLCs and actuators).

Civil Engineering

To handle excavation, filling, and utility services (drainage, sewer, water, etc.).

Structural Engineering

To ensure foundations are safe and sound to support the structural load of the building bearing the process equipment.

Building Mechanical Engineering

To handle all aspects of ventilation, fire protection, lighting, non-process electricity and plumbing.

Architecture

To handle all technical and visual aspects of the site and buildings.

Detailed engineering is performed to generate drawings and establish specifications for all the components of the biogas plant. The design must obviously comply with local codes and regulations.

PERMITTING & ENERGY CONTRACTING

Once the drawings and specifications are completed, the project must obtain all necessary permits for construction. Depending on the jurisdiction, there are usually several different authorizations required from local municipalities and environmental agencies.

In parallel, an energy contract should be negotiated with the local energy provider. These contracts can be technically and legally complex and will require proper technical and legal support.

Do not underestimate the time required to perform permitting and/or negotiate an energy contract with energy providers.

FINANCING

Financing will only occur if the project is permitted and if there is a serious client for the biogas energy.

Equity and guarantees will be demanded by financiers. Due diligence will be performed on the design, the clients, the management, risk analysis, etc.

Only upon satisfying all these answers will the project funding be confirmed.

PROCUREMENT

Purchasing the products and services to realize the design. Typically, the procurement of the plant will be broken down into several contracts, such as:

Site decontamination

Civil works

Foundations/concrete work

Quality control labs (materials)

Building structure

Building envelope

Building mechanicals

Electrical

Automation

Process equipment (digesters, gas upgrader, hydropulper, conveyors, etc.)

Mechanical installation

Construction management

Engineering supervision

Public entities, such as a municipality, will often issue a request for proposals (RFP) for a design-build (DB) or a design-build-operate (DBO) so that all these procurement contracts are performed by the chosen contractor. Municipal procurement is often cumbersome and slow, thus one should expect significant potential delays in the realization of the biogas project.

CONSTRUCTION

Once all the permits are granted and the financing obtained, the procurement and construction can begin.

Proper construction management, supervised the general contractor, is essential to ensure that procurement and the execution of the various contracts are well timed to avoid construction conflicts and unnecessary delays.

Engineering supervision is necessary to ensure that the constructions are in accordance with the design.

Construction sites must be managed properly to ensure security and safety of the workforce. The site must be able to accommodate temporary services (electricity, sanitation, accommodations, etc.) as well as material and equipment reception (laydown) and storage.

COMMISSIONING

Upon completion of the various phases of the biogas project, pre-operational verifications must be performed to ensure that all equipment was properly installed. At this point in time, a partial acceptance of the biogas plant can be granted so that the various contractors can get paid.

After verification, the anaerobic digestion process may be started. There must be a proper coordination with the feedstock collectors to ensure they can sufficiently and efficiently supply the process with the feedstock.

Upon achievement of the performance of the biogas plant, a final acceptance may be granted to pay the balance of suppliers and officially begin the operation of the biogas plant.

OPERATION

Day-to-day operation of the biogas plant includes the following tasks:

Reception of Material

Operators will coordinate the logistics of feedstock arrival, perform visual inspection of the received material, and log tonnages received.

Conditioning of Material

Operators will transfer the material from the reception to the conditioning equipment.

Anaerobic Digestion Process Control

Operators will operate and monitor the various aspects of the anaerobic digestion process, such as temperature, OLR, FOS/TAC, pH, etc.

Operation of Digestate Treatment System

Operators will attend to the dewatering, drying, and water treatment processes.

Operation of Wastewater Process

Operators will ensure that the water treatment process is functional.

Disposal of Contaminants

Operators will manage the logistics and disposal of all contaminants generated by the process.

Operation of Composting Process (if there is)

Operators will operate and monitor the various aspects of the composting process.

Disposal of Digestate/Compost

Operators will manage the disposal of the digestate/compost.

MAINTENANCE

Biogas plants are equipped with multiple equipment that must be maintained to remain optimally functional throughout their entire planned life cycle.

Also, operators must establish and perform preventive maintenance on the equipment.

Unplanned maintenance and repairs are also to be expected and required daily.

OPTIMIZATION

Optimization of the biogas plant may be achieved by performing modifications to improve processes or performance.

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We can do the following for you:

– Generate more excess power to sell.

– Ceate more business revenue.

– Solve your environmental wastewater problems.

– Manage organic waste stench and storage.

– Extend boiler fuel inventory.

– Start a zero-waste system without really trying.

– Offer leading integrated W2E technology.

– Raise efficiency of power generation system.

We are PlanET Biogas Global GmbH. We have designed, engineered, and constructed over 430 biogas and biomethane plants all over the world. We can help you quantify, qualify, and harness the potentials of ALL your organic waste.

Biogas and Biomethane. Turning waste into resources.

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/

BIOGAS PLANT DEVELOPMENT HANDBOOK. PART 3.


6. INPUT FEEDSTOCK

The feedstock dictates the biogas technology to be used, not the other way around. In order to properly design a biogas plant, the developer must fully understand its feedstock.

How will the feedstock be collected and arrive at the biogas plant? How much of it? When will it come? Which form, liquid or solid? Which type of trucks? Is there a significant variation in volumes throughout the seasons? Will this volume increase or decrease over the years?

A significant amount of work must go into trying to model the variation of feedstock throughout the days, months and years of a project. Without this information, it is likely to lead to improper sizing of biogas plants resulting in an inefficient operation and investment.

The composition of the feedstock must also be well known to identify the most suitable technologies to process this material. Furthermore, understanding feedstock composition will allow forecasting digestate quality which will help identify outlets for the digestate.

A detailed analysis of the feedstock composition from a trusted laboratory will outline the following feedstock properties:

• Dry matter content or total solids (TS)

• Volatile solids (VS)

• Total Kedjhal Nitrogen (TKN)

• pH

• Alkalinity

• Contaminants (plastics, glass, metals, etc.)

The total solids test consists of completely drying the material to determine the mass ratio of solids versus the water in the material. For example, dairy cow slurry typically contains 10% solids and 90% water.

The volatile solids test consists of burning (600 °C) the solids from the total solids test to determine the mass ratio of volatile solids (burned) versus ashes.

Note that lignocellulosic material (wood) and plastics will volatilize but are, in fact, not digestible by anaerobic digesters.

Furthermore, anaerobic digestion may be hindered by various inhibiting compounds such as sulfur, salts, ammonia, etc.

For these reasons, additional tests may be performed on the feedstock to determine digestibility, long-term stability and biogas yield. Laboratories with biogas expertise will offer the following tests:

• Biomethane Potential (BMP)

• Anaerobic Toxicity Assay (ATA)

• Continuous Digestion

7. BIOGAS PROCESS TECHNOLOGIES

Anaerobic digestion processing technologies are divided into two major families:

• Wet digestion

• Dry digestion

In either case, these technologies offer either batch or continuous processes.

WET DIGESTION

The process is considered wet digestion when the content of the digester is pumpable. That means that the material inside the digester has a consistency of approximately 10% dry matter or less (90% water).

There exist many configurations of wet digesters:

• Complete mix or Completely stirred tank reactor (CSTR)

• Plug-flow

• Upflow Anaerobic Sludge Blanket (UASB)

• Fixed film reactor

• Floating films reactors

• Sludge bed reactors

• And more.

These configurations have been designed to optimize the process for various feedstock conditions and market applications.

The mass balance of a typical wet digestion process looks like this:

For example, 100 tonnes of solid municipal residential source separated organics (SSO) arrives at the biogas plant using wet digestion (complete mix). This feedstock needs to be pretreated to remove potential contaminants (plastics, metal, sands, etc.). Approximately 10 tonnes will be removed as contaminants and will probably be landfilled.

In order to be pumpable (10% TS), the feedstock will be diluted with water that may come from a fresh source or from a mixed of fresh and recycled water from the wastewater portion of the biogas plant. The liquid feedstock going to the digester will be approximately 250 tonnes.

In the digesters, the bacteria will consume the majority of the volatile solids in the feedstock and will convert them into biogas. Approximately 10 tonnes of gas will come out of the digesters. The more liquid digestate will represent approximately 240 tonnes.

At this point, the digestate may be applied to land directly. Please note that 100 tonnes of solid material turned into 240 tonnes of liquid and land applying the digestate in this form will present significant transportation costs.

The digestate may also be separated into a solid fraction (45 tonnes) to be land applied (or composted down to 35 tonnes) and a liquid fraction (195 tonnes) to be returned the sanitary sewage or directly back to nature.

One may be tempted to use the treated wastewater as dilution water for the input feedstock and limit the amount of water consumed and rejected by the process. It is possible only if the wastewater plant removes almost all nutrients (salts and ammonia/ammonium) in the water. Without this removal, there will be a rapid build up of nutrients in the water and this will inhibit and/or kill the anaerobic digestion process.

DRY DIGESTION

The process is considered dry digestion when the content of the digester is not pumpable. That means that the material inside the digester has a consistency of approximately 10% dry matter or more.

There exist many configurations of dry digesters:

• Continuous vertical

• Continuous horizontal

• Batch (Garages)

• And more.

These configurations have been designed to optimize the process for various feedstock conditions and market applications.

The mass balance of a typical dry digestion process

For example, 100 tonnes of solid municipal residential source separated organics (SSO) arrives at biogas plant using dry digestion (garage style). This feedstock does not need to be pretreated to remove potential contaminants (plastics, metal, sands, etc.).

In the digesters, the bacteria will consume the majority of the volatile solids in the feedstock and will convert them into biogas. Approximately 10 tonnes of gas will come out of the digesters. The solid digestate will represent approximately 90 tonnes. Note that the digestate coming out will be more liquid than the incoming material. In some cases, it may be necessary to add some bulking agent prior to digestion to ensure the out outgoing material remains solid.

In certain continuous “dry” digesters the material can come out as a thick liquid. In these instances, this liquid is still contaminated with (plastics, metals, rock, sands, etc.) and is very difficult material to recycle to land.

In our example, the solid digestate cannot be applied to land directly because the contaminants have not yet been removed. In order to remove the contaminants, the material will have to be dried enough to allow sieving without clogging the screens.

The most efficient way to dry this material is to compost it with drier material such a garden waste. Compost is a science of its own and will not be discussed here. However, we will mention that composting often required a bulking agent (25 tonnes) to ensure proper material structure complying with aerobic composting conditions. The bulking agent will be added to the tonnage of material to be sieved to achieve recycle to land quality.

The digestate may also be separated into a solid fraction (45 tonnes) to be land applied, and a liquid fraction (195 tonnes) to be returned the sanitary sewage or directly back to nature.

Here also, one may be tempted to use the treated wastewater as dilution water for the input feedstock and limit the amount of water consumed and rejected by the process. As with wet digestion, it is possible only if the wastewater plant removes almost all nutrients (salts and ammonia/ammonium) in the water. Without this removal, there will be a rapid build up of nutrients in the water and this will inhibit and/or kill the anaerobic digestion process.

WET VERSUS DRY DIGESTION

As illustrated in the examples above, there is no silver bullet, and it is not true that dry digestion resolves all wastewater issues since composting plants have leachate treatment challenges of their own.

In the example above, using the wet digestion process resulted in 100 tonnes of SSO being converted into 45 tonnes of solid digestate and approximately 100 tonnes of wastewater (some recycled). The result of dry digestion process is 80 tonnes of compost recycled to land prosessed within a composting plant of equal size to the biogas plant.

In general, it is possible to remove ammonia from the wastewater the wet digestion is favored, and if the composting is possible the dry digestion is used.

Ad.

More Generated Power from Waste.

Advance technology + automation + experience + expertise = Innovation

We can do the following for you:

– Generate more excess power to sell.

– Ceate more business revenue.

– Solve your environmental wastewater problems.

– Manage organic waste stench and storage.

– Extend boiler fuel inventory.

– Start a zero-waste system without really trying.

– Offer leading integrated W2E technology.

– Raise efficiency of power generation system.

We are PlanET Biogas Global GmbH. We have designed, engineered, and constructed over 430 biogas and biomethane plants all over the world. We can help you quantify, qualify, and harness the potentials of ALL your organic waste.

Biogas and Biomethane. Turning waste into resources.

https://jcgregsolutions.wordpress.com/2018/08/16/more-fuel-to-extend-operations-and-generate-more-excess-power/

Jess C. Gregorio

PlanET Biogas Global GmbH

Email: j.gregorio@planet-biogas.com

Email: gregoriojess@yahoo.com

Website: http://en.planet-biogas.com/

Biogas Reference Site:

https://jcgregsolutions.wordpress.com/category/solutions-biogas/