BIOREP (FR1.1)

The BIOREP facility is a high pressure set up to perform percolation and transfer experiments on fluid-rock interactions under a large range of pressure and temperature conditions, while continuously monitoring geochemical and bio-geochemical evolution. The facility is particularly adapted to monitor biological system evolution during the experiment.

The range of pressure and temperature of BIOREP allows simulating conditions that are typical for CO₂ storage or for CO₂ leakage, along a deep well or in the overburden. It could be also employed to simulate other subsurface storage conditions (e.g. other gas, water, oils) and systems of exploitation (e.g. geothermal, in-situ biolixiviation).

The facility could be used to do classical batch experiments, equilibration or transfer experiment between compartments through columns and also microfluidic percolations in highly pressurized micro-chips.

Brief technical description with picture and/or diagram

The percolation is performed between 2 or 3 high pressurized batch cells, with a high pressure syringes or a pump and can be applied to fluids (gas or liquids, supercritical fluids). Different setup can be realized in order to answer specific questions (i.e. with different types of regulating modules between these cells). For instance: Batch A can be set up with a predefined geochemical equilibrium and a gas phase can be introduced. A chosen reaction matrix (being crushed rock, sediments, pellets or synthetic material) inoculated with microorganisms can be tested in different percolation systems (column, Hassler cell or microcells). The B batch allows collecting fluids after percolation for sampling purpose. At the end of experiment, the column can be analysed.

Experimental conditions: Temperature from -10 to 120°C. Pressure up to 200 bar.

Materials in contact with fluids: PTFE, PEEK, C276 (Hastelloy) and silica and borosilicate for the microfluidic cells.

Advantages (technical, economic…)

Thanks to its modular and compartmentalized conception, BIOREP allows a wide range of experiment to study microbiological and geochemical processes with in situ conditions – typical for CO₂ storage or related to (well, overburden condition).

All the gases and liquids can be collected under pressure or progressively degassed to avoid the risk and biases linked to decompression.

Besides those basic principal characteristics and adaptation, the BIOREP facility is divided in three different modules that allow specific approaches:  

• TRANSREP

Three reactors platform with transfer patterns that can be designed according to the desired experiment

• MICROREP

Microfluidic and analytical lines that allow the transfer of pressurized fluids into microchips and captors/ electrodes with low consumption of experimental fluids. The microfluidic approach also allows to perform spectral (IR/RAMAN) characterization.

• CYCLOREP

Closed loop build to recirculate fluids into an Hassler cell. This design is particularly suitable to experiment and assess the stabilization phases of an injected fluid through rock percolation. The module also allows to measure any loss or collapsing effect of the rock plug. It is particularly suitable to study injectivity.

• MULTIREP

Three Hassler like reactors that allow to handle different types of sample and conditions at the same time.

The facility situated in BRGM research centre in Orléans, France, benefits from the support of the different laboratory and technicians from BRGM. The team managing BIOREP will provide support in designing and setting up experiments. In addition, chemical, biological and mineral characterization of samples can be provided by BRGM (including Raman). Modelling of the experiments and reactive transport processes is also possible and can be provided.

BIOREP allows the monitoring of microbiological systems in high pressure and dynamic conditions, which is unique. In specific, BIOREP differs from other facilities on the following properties:

• Respect of the biologic neutrality of the containment and limit the risk of bio-corrosion associated. Most material in contact with the studied medium and biological system is Téflon or Hastelloy.

• Sampling procedure and process adapted to micro biological material to ensure a slow decompression and avoid cell lethality related to decompression.

• Possibility of managing independently the batch’s geochemistry and therefore to create gradients through the column between the two batches (for instance between oxic and anoxic areas).

• Possibility to use geological laboratories on chips as well as transfer cells (Hassler cell, columns).

• Pressure, temperature, gas consumption and regulation, flow rate, pH and redox can be monitored on line depending the designed setup and with the highest standard of precision.