Our Businesses / Renewables

Anaerobic Digestion

Turning organic waste into renewable energy, with the biology, gas treatment and support to keep your plant performing.

What Is Anaerobic Digestion?

Anaerobic digestion (AD) is a natural biological process. Microorganisms break down organic material in the absence of oxygen. The result is biogas, a renewable fuel, and digestate, a nutrient-rich fertiliser. When biogas is upgraded, the CO₂ removed is biogenic CO₂, a valuable by-product in its own right.

AD takes materials that would otherwise be waste, such as slurry, food waste, crop residues and industrial by-products. It turns them into heat, power, transport fuel or biomethane for the gas grid. It is a true circular solution, and a key part of the move to a low-carbon economy in Ireland, the UK and across Europe.

But AD is a complex living system. A healthy digester depends on stable biology, and the biogas it produces needs careful treatment before it can be used. That is where Nova Q comes in.

How Anaerobic Digestion Works

Feedstock in

Slurry, food waste, grass silage or industrial by-products are mixed and fed into a sealed, oxygen-free digester.

Breakdown by microorganisms

Bacteria and archaea break the material down in four stages: hydrolysis, acidogenesis, acetogenesis and methanogenesis.

Biogas is produced

Raw biogas is mostly methane and carbon dioxide, with traces of H₂S, siloxanes, ammonia and moisture.

Biogas is cleaned

Contaminants are removed to protect CHP engines, boilers and downstream equipment.

Used or upgraded

Clean biogas makes heat and power in a CHP engine, or is upgraded to biomethane for the gas grid or transport.

Biogenic CO₂ captured

The CO₂ separated during upgrading comes from recently grown organic material, not fossil fuels. It can be captured, purified and reused in food and drink, greenhouses and industry.

Digestate back to land

What remains is a valuable fertiliser, returning nutrients to the soil and closing the loop.

NOVA Q
service areas

Biology

Activated Carbon

Biogas Upgrading

H₂S Management

Nova Q supports AD from the feedstock to the gas grid. Highlighted stages are where our four service areas work.

How Nova Q Supports Anaerobic Digestion

We work with AD operators at every stage, from the biology inside the digester to the quality of the gas that leaves it. We help you get more from your plant, protect your equipment and meet your targets.

Biology

BluePlanet™ bacteria for faster hydrolysis, stable digesters and quicker start-up and recovery.

H₂S Management

EnviroChem Metha controls H₂S at source, so far less is left for iron and carbon to handle.

Activated Carbon

Carbons, mobile filters and reactivation to remove H₂S, siloxanes, VOCs and ammonia.

Biogas Upgrading

A major new biogas upgrading project is on the way. Coming soon.

Biology

A Healthy Digester Starts With Healthy Biology

BluePlanet™ Bacteria for Anaerobic Digestion

Two complementary products: AD Activator to speed up hydrolysis at the front end, and ACF-SA to keep the whole process stable. Both are natural, non-pathogenic and free of GMOs.

Enhanced biological hydrolysis

BluePlanet™ AD Activator

Naturally occurring bacteria and nutrients that produce targeted enzymes. Activated on site in an aerated bioreactor for 48 to 72 hours, then dosed to a pre-hydrolysis stage or straight to the digester.

Faster hydrolysis of fibrous and complex solids
Lower solids and viscosity, for better mixing, pumping and digestate handling
Breaks down crust and limits its return in primary and secondary digesters
Faster gas production from hydrolysed feedstock

Best for: fibrous or solids-rich feed, crust, viscosity or pumping problems.

Biological stability and start-up

BluePlanet™ ACF-SA

Naturally occurring bacteria with readily bioavailable micronutrients and trace elements, in a stable liquid. A probiotic and prebiotic supply in one product.

Consistent biological stability, for improved gas quality and yield
Rapid recovery from FOS/TAC spikes
Faster start-up of new or re-seeded digesters
Significantly reduces odour

Best for: rising or unstable FOS/TAC, variable feedstocks such as poultry litter and pig slurry, start-up or re-seeding.

Used together

4 to 6 weeks

Typical time from start-up to stable operation. Recovery is usually much faster: Nova Q has recovered plants in just a few days.

Field result with ACF-SA

3,700 → 5,500 Nm³/day

Gas output at a food waste and cattle slurry AD site, February to April 2018, with total feed back at similar levels by the end of the period.

A programme for your plant. Dose rates depend on your feedstock, solids content, loading rate, retention time and temperature. Send us your feedstock and process data and we will recommend a BluePlanet™ programme for your plant.

Download the technical data sheet

Talk to us about your digester

H₂S Management

H₂S Control at Source

EnviroChem Metha

Most of the H₂S in a digester starts as sulphur bound in the proteins of the feedstock. Iron, activated carbon and air dosing all treat that gas once it has formed.

EnviroChem Metha works a step earlier, holding the sulphur in the feedstock so that far less of it is released as H₂S in the first place.

How It Works

Metha is a liquid contact agent dosed onto the incoming feedstock, upstream of the digester, at around 1 litre per 10 tonnes. It slows the release of sulphur from protein without harming the digester biology, and it is not a biocide.

Lower H₂S at source
Steadier methane
A smaller load left for iron and carbon to handle

Where It Works Best

Metha performs best on protein-rich feedstocks:

Food waste
Slaughterhouse and dairy by-products
Poultry litter
Spent grains

Where the sulphur is largely mineral, iron remains part of the solution. We will tell you before any trial how far Metha can go on your site.

H₂S in biogas · reference sites

1,000–1,300 ppm → 120–150 ppm

Brought down into the normal operating range.

Daily dose per digester · household waste plant

35 L ferric chloride → 1 L Metha

A fraction of the chemical volume to store and handle.

Supported from start to finish. Nova Q supports every application, from feedstock assessment through dosing design to trial supervision. Download the technical data sheet and complete the customer questionnaire, and our team will come back to you with a tailored recommendation.

Download the technical data sheet

Complete the customer questionnaire

Activated Carbon

Biogas and Biomethane Purification

In partnership with Puragen

Raw biogas carries trace contaminants that damage engines, foul equipment and stop gas from meeting grid standards. Our activated carbon products and services remove H₂S, siloxanes, VOCs and ammonia. They upgrade raw biogas to high-quality biomethane that meets gas-to-grid injection standards and protect your CHP engines.

As Puragen's partner in Ireland, we bring their carbon technology, mobile filters and reactivation service to Irish AD plants, backed by local stock and support.

What We Remove

Hydrogen sulphide: toxic and corrosive to engines and pipework
Siloxanes and VOCs: including pinene and limonene, which leave abrasive deposits
Ammonia and odours: removed to protect equipment

Carbon for Every Job

Granular activated carbon: high-capacity adsorption of VOCs and siloxanes
Extruded pellets: low pressure drop and the right contact time
Impregnated carbons: treated to target H₂S and ammonia

A Full Service

Expert support and lab analysis
Fixed filter supply, carbon exchange, maintenance and optimisation
Manifolds fabricated and engineered for any application
Spent carbon reactivated through a closed-loop process, a circular alternative to disposal