Enabling more efficient biogas upgrading

In today’s low carbon world, biogas presents a compelling alternative to natural gas

Fast growing market demand for renewable energy sources and incentives to generate biogas from waste has put suppliers and operators of biogas upgrading plants under increasing pressure to accept a diverse range of feedstocks.  This leads to unpredictable levels of volatile organic compounds (VOCs) in the gas that can significantly impact the efficiency and uptime of the plant.  Where biomethane is being injected to the gas grid the commercial penalties and risks can be severe if purity levels are not consistently met.

Advanced, real-time online VOC monitoring

BioSpec VOC accurately monitors individual ketones and terpenes as well as hydrogen sulphide, ammonia and other components. This gives operators a clear, accurate and real-time picture of the removal of the VOCs from the biogas and enables the upgrading plant to be managed more efficiently. Advanced optical absorption spectroscopy technology is used to analyse all the individual VOC components in a single measurement.

Reduced operating costs

BioSpec VOC reduces the operational cost of activated carbon filters, safeguards separation membranes and reduces the total cost of upgrading biogas to biomethane.

Maximise Uptime

Monitoring of the VOCs enables plant uptime to be increased and grid supply obligations to be met.

No Recalibration

The device does not require any further recalibration in the field during its lifetime, eliminating the need for calibration gases to be held onsite.

Multiple Sample Points

Measurement at multiple sample points allows for analysis of the biogas before, during and after the upgrading process with a single solution.


Biomethane Specification

Biomethane must meet a certain specification for grid injection or use as a vehicle fuel. Monitoring VOCs and other contaminants provide an additional level of confidence and security in knowing that the biomethane produced complies with the specifications required.


CO2 Removal

BioSpec VOC improves the operational efficiency of the biomethane plant by helping avoid the risk of VOCs breaking through into the CO2 removal process (biogas upgrading) and the consequent costs in their loss of efficiency or potential replacement. For example, VOC breakthrough can cause damage to separation membranes and void warranty cover.  Impurities such as VOCs can also reduce the efficiency of PSA upgrading technology.  BioSpec VOC provides assurance that these contaminants are removed, mitigating against the risk of  reduced throughput and plant downtime.


Activated Carbon Filters

BioSpec VOC can continuously monitor the composition of the biogas between each activated carbon filtration stage. All components are measured in a single measurement and are reported on an individual level. This is vital as different components break through the activated carbon filters at different rates. This provides the earliest indication of activated carbon filter saturation. By monitoring the VOCs, you can ensure that the activated carbon filters are replaced at the optimal time, thus helping to reduce operational costs on filter replacement.



Raw Biogas

BioSpec VOC can monitor the composition of the biogas before it passes through the activated carbon filters. This information can be used to select the best type of activated carbon needed for purifying your biogas, depending on the type and concentration of contaminants in the raw biogas.


Sources of Biogas Impurities

Common volatile organic compounds and other contaminants found in biogas include p-Cymene, limonene, pinenes, hydrogen sulphide, ammonia and more. These impurities can come from a wide range of feedstock sources, such as food waste, garden waste, cosmetics, household products, farm waste, wastewater and landfill. BioSpec VOC measures all of these components and many more.



BioSpec VOC uses an ultraviolet optical absorption spectroscopy technique to measure individual contaminants in the gas mixture. This is the ideal technology for monitoring VOCs and optimising the performance of biogas upgrading plants. There is zero sensor drift with this measurement technique and no recalibration or carrier gases are required. These benefits allow for ease of operation and minimal ongoing costs associated with operating the analyser.


Measured Gas Components

As standard, BioSpec VOC measures and reports individual concentrations for each of the following components in every measurement:

Acetone, 2-Butanone (MEK), 3-Carene, alpha-Pinene, beta-Pinene, Limonene, p-Cymene, Xylenes (m, o, p), DMS, CS2, H2S, NH3

The innovative choice for biogas upgrading plants

Significantly more reliable and cost-effective than conventional Gas Chromatography (GC) instruments, BioSpec VOC has been designed specifically for the purpose of VOC monitoring in biogas upgrading plants. It is straightforward for OEM upgrading plant suppliers to integrate the solution into their specific systems. This enables a more holistic solution to be offered and sustainable profits delivered to plant owners.

Flexible Installation

BioSpec VOC can be installed in new plants and retrofitted into existing installations.

Easy Integration

Concentrations, trends and alerts on VOC content is easily integrated into operating systems.

Simple Operation

No specialist expertise is necessary to operate the device.


Minimal Maintenance

Low maintenance, no recalibration and no costly consumables required.

Customer References

BioSpec VOC is supplied to and marketed by Pentair under the BioSENSE brand name