LBG Production with MachOne Cryochiller

MachOne's Cryochiller uses a reverse Brayton cycle with nitrogen circulating in a closed loop. Proprietary high-speed centrifugal compressors and a turboexpander cool the nitrogen, which then provides the refrigeration required to liquefy the biomethane through a heat exchanger.

The nitrogen refrigerant remains physically separated from the biomethane. This indirect cooling arrangement protects the product gas from cross-contamination and avoids using a hydrocarbon as the refrigerant inside the cooling cycle.

How the LBG Process Works

1. Biomethane Supply

The upstream upgrading plant removes the bulk of the CO₂ and other unwanted components from the raw biogas. The liquefaction system is designed around the actual biomethane composition, pressure, temperature and flow profile.

2. Final Polishing

Before liquefaction, the gas is polished to prevent CO₂ and water from freezing in the cryogenic equipment. MachOne's current process basis typically targets below 50 ppmv CO₂ and below 1 ppmv H₂O before the gas enters the cold section.

3. Cryogenic Cooling

The closed nitrogen loop supplies cold to the biomethane through the heat exchanger. The system is configured for the required LBG storage condition, typically around −150°C to −160°C depending on the downstream use and storage pressure.

4. Off-Gas Recovery

Gas released during polishing can be returned to the upgrading process or another suitable upstream point when the overall plant design allows it. This reduces methane loss compared with simply venting the stream.

5. Storage and Offloading

The finished LBG is transferred to an insulated cryogenic tank and prepared for loading into a tanker. Storage volume, holding time, pressure, boil-off-gas handling and loading capacity are defined for the site's production and collection schedule.

Biogenic CO₂ Purification and Liquefaction

The CO₂-rich stream from a biogas upgrading plant may still contain moisture, methane, oxygen, nitrogen, H₂S, VOCs and other trace components. The treatment train is therefore configured around a complete gas analysis and the quality specification for the intended liquid CO₂ market.

Why MachOne?

Two Product Routes, One Coordinated Project

LBG and liquid CO₂ can be developed as separate systems or as one coordinated plant concept. Aligning feed streams, utilities, controls, storage and offloading early reduces interface risk and gives the project a clearer overall operating basis.

Proprietary Cryogenic Technology

MachOne develops and manufactures the high-speed motors, centrifugal compressors and turboexpanders at the core of its Cryochiller. The closed nitrogen cycle can deliver the low temperatures required for biomethane liquefaction without direct contact between the refrigerant and the product gas.

Modular and Transportable

Containerised and skid-mounted sections are assembled, wired and tested before shipment. This limits the connections required on site and supports both new plants and retrofit projects where available space or construction time is constrained.

Scalable for Distributed Production

The modular concept allows liquefaction capacity to be matched to the biogas plant and expanded by adding units. This is particularly relevant for sites that are distant from a suitable gas grid or want an additional route to market.

Flexible Product Specifications

LBG temperature and pressure, liquid CO₂ grade, storage capacity and loading arrangement can be configured around the intended customer and logistics model. The process is not treated as a one-size-fits-all package.

Automated Operation and Remote Support

The systems can include PLC-based automation, remote monitoring, alarm management, operating-data storage and integration with the customer's control system. Service, spare-parts and maintenance responsibilities are agreed for each project.

Biogenic CO₂ Purification and Liquefaction

The CO₂-rich stream from a biogas upgrading plant may still contain moisture, methane, oxygen, nitrogen, H₂S, VOCs and other trace components. The treatment train is therefore configured around a complete gas analysis and the quality specification for the intended liquid CO₂ market.

How the CO₂ Process Works

1. Feed-Gas Cleaning

Where required, dedicated activated-carbon beds or other treatment stages remove H₂S, VOCs and relevant trace contaminants. The exact pretreatment depends on the upgrading technology and the incoming CO₂ composition.

2. Compression and Drying

The cleaned gas is compressed and dried with molecular sieves. Removing water before the cold section prevents ice formation and protects stable operation.

3. Liquefaction and Separation

The dry CO₂-rich gas is cooled and liquefied. A separator can produce an industrial-grade liquid stream, while a cryogenic stripping configuration provides deeper removal of non-condensable components for higher-purity applications.

4. Quality Control

Product quality is verified against the agreed specification. An integrated analysis system can monitor CO₂ concentration and relevant trace contaminants, support batch documentation and provide the traceability required by the selected market.

5. Storage and Offloading

The liquid CO₂ is held in insulated storage and transferred by pump to a road tanker or the site's downstream process. Tank capacity and loading arrangement are sized around production rate and collection frequency.

Industrial or Food-Grade CO₂?

CO₂ concentration alone does not determine whether a product is food grade. A high-purity system can be designed to produce liquid CO₂ above 99.99%, but acceptance for food or beverage use also depends on limits for trace contaminants, continuous or batch analysis, sampling, documentation, traceability and the standards required by the buyer and local market.

For this reason, GGS recommends defining the intended CO₂ customer and quality specification at the beginning of the project. The treatment process, analyser package, storage system and operating procedures can then be designed around an agreed and verifiable requirement.

Applications

LBG / Bio-LNG

• Heavy-duty road transport

• Marine fuel and bunkering

• Off-grid industrial energy supply

• Virtual-pipeline distribution

• Flexible storage and transport of renewable gas

Liquid Biogenic CO₂

• Industrial process use

• Greenhouse enrichment

• Refrigeration and cooling applications

• Food and beverage applications when the complete product specification and quality requirements are met

• CCS - permanent underground storage

• Carbon utilisation and Power-to-X (PtX), including e-methanation, e-SAF and other renewable synthetic-fuel pathways

Integrated with the Biogas Plant

Liquefaction performance depends on the upstream process and the downstream logistics. GGS can help coordinate the interfaces between the MachOne solution and other specialist systems, including:

• Raw-biogas pretreatment and H₂S removal

• Biogas upgrading and biomethane polishing

• Biomethane and CO₂ compression

• LBG and liquid CO₂ storage

• Tanker loading and offloading systems

• Gas analysis and product-quality control

• Plant controls, remote access and data exchange

• Commissioning, training, service and maintenance

GGS acts as the Nordic commercial and technical interface. MachOne and the relevant specialist suppliers retain responsibility for their technologies and the delivery scope agreed in the final proposal.

Planning an LBG or CO₂ Project?

Send us the available gas data and your intended product routes. GGS and MachOne can use this information to establish a preliminary process concept, identify critical interfaces and define what must be verified before equipment sizing and performance guarantees.

Useful Project Data

• Existing or planned biogas-upgrading technology

• Minimum, nominal and maximum biomethane flow

• Biomethane composition, pressure, temperature and moisture

• Minimum, nominal and maximum CO₂-rich off-gas flow

• CO₂-stream composition, including CH₄, O₂, N₂, H₂S, water, VOCs and other known contaminants

• Target LBG production, temperature, pressure and end use

• Target liquid CO₂ production, grade and intended customer or application

• Annual operating hours and expected load variation

• Available electrical power, water, cooling and compressed air

• Required storage capacity and tanker collection frequency

• Site layout, ambient design conditions and ATEX classification

• Required redundancy, availability, remote support and service scope