Our Nautilus BMP/RBP (biomethane potential) set has been developed based on operational research in the UK food waste industry. All our Nautilus sets INCLUDE our gas flow meters with real-time conversion to standard temperature and pressure using our custom data logging software. Through hundreds of tests done by ourselves, and thousands of tests by our clients, our machines have been thoroughly evaluated for practicality, results quality, and durability, NRM lab alone has 34 of our Nautilus machines  in continuous operation doing certified RBP tests.

Before developing our machine, we used reactors with individual mixer motors and found that, although the final biogas yield after 30 days was similar, small changes in mixer speed, or a mixer motor failing impacted the kinetics of the biogas production for individual samples. We have developed a patent  gearbox mixer system that, through one motor alone, mixes all 15 reactors at the same speed under homogeneous thermal conditions. Our BMP reactors are 1 litre wide mouth HDPE bottles to minimize errors in measurement and lead to the most accurate and reliable results.

Our reactors have a wide mouth design that allows you to load them with the desired inoculum and sample without any hassle. You can then fit the reactor tops and place them in the water bath, which has a lid and a gearbox to align the reactors. Our reactors also come with a gas flow meter hose that you can connect to monitor the biogas production. You can flush the gas if needed and adjust the temperature and mixing speed of the water bath. Air-tight ports also enable pH monitoring, nutrient supplementation, or sampling without disruption to batch tests for repeatable and consistent results. 

Minimum Water Evaporation

We use widely available HDPE bottles as our reactors, which are durable, cost-effective, and have a large active volume for more accurate testing*. Our water bath has Perspex lids that prevent water vapour from escaping and condenses it back into the bath. This ensures minimal water loss even in thermophilic operation. 

Unmatched Consistency

Our Nautilus BMP is designed to give you the most accurate and consistent results. We use larger 1-litre reactors that can accommodate heterogeneous inoculum and substrate samples, reducing the error caused by small variations in fat content. We also use top of the range Grant © water baths that maintains a stable temperature for the reactors. Moreover, a single mixer motor is used that ensures uniform mixing intensity for all reactors, even if unstirred whilst keeping replacement costs low.

Our Arduino-based system is a Open-Source state-of-the-art data logger . When one of the tumblers in the gas flow meter tips, a magnet attached to the tumbler bucket causes the reed switch to close and records  the volume in real time. Also connected to the Arduino are a  BMP280 barometric pressure sensor, a microSD card reader,  and a thermocouple amplifier to which is connected a type-K thermocouple.  All tumbler events are written to a log file on the microSD card including the channel number, the time at which the event occurred, the air pressure at that time and the temperature as recorded by the thermocouple.

​For ease of use, other log files (e.g a summary of what has happened in the last 24 hours) which are calculated from this event data, including standard temperature and pressure (STP) conversion are also stored on the memory card. A suite of Python utilities has also been developed to simplify set up and operation of the data logger. All raw and processed gas flow data can be downloaded in csv format and readily converted to graphs, or exported for specific mathematical analysis.This enables simple data extraction for easy no hassle analysis.