DescriptionThe Salsan II rig was build in the winter 2014/2015. Central to the set-up is a dip-tube salt separator. The special "zircalloy" vesel originally designed for the 2005 salsan campain by Andrew Peterson was re-used. In this previous study, salt separation was visualised using neutron radiography. Zircalloy was used as construction material as it is transparent for neutrons.
The objective of this set-up is to study the separation and deposition of salts under hydrothermal conditions and to obtain data that complement CFD simulations of the flow inside the salt separator.
Characteristics of the set up
- Up to 320 bar
- T max. 450°C
- V* = 20 ml/min.
- Vessel volume ca. 50ml
- 9 individually controlled vessel heaters
Features of KONTI C:
- Microalgae pumped as a slurry (10 - 20 wt. % of DM) at 1 kg/hours
- Pressure max = 40 MPa
- Temperature max = 550 °C
- New salt separator design (patent filed)
- Gaseous effluents analysed online by a MicroGC
- Liquid effluents analysed online by TOC and conductivity
- Highly automated (liquid sampling, temperature profile measurements) and remote controlled.
The biomass-water-mixture is sent to the reactor that can be filled with different types of catalysts to be tested. After a pressure regulation valve and a phase separator, the liquid products can be examined with our TOC apparatus in terms of carbon content or in our HPIC to identify chemical compounds. The gas is sent to a gas chromatograph and is being analyzed it in a continuous way.
- Liquid biomass model substances
- Pmax 40 MPa
- Tmax 550 °C
- Ratio biomass / water variable
- Long-term catalyst stability testing possible
- Online GC analyses, offline TOC and HPIC analyses by sampling
The KONTI-2 is a continuously operating laboratory plant built to demonstrate the process of the hydrothermal gasification of real biomass to methane and carbon dioxide. A hydrothermal environment (conditions of subcritical or supercritical water, 25-35 MPa and 350-450 °C) is used for the gasification because biomass with a high water content or organic containing waste waters serve as feed. Unfortunately no slurries can be fed due to the small scale of the PDU (feed stream about 1 kg/h - there is no pump available which is able to pump slurries at that scale), so liquid biomass has to be used.
The LabVIEW™ program is used to monitor pressures and temperatures to control the heaters and to switch the pumps.
The plant consists of seven sections:
- Feeding: The biomass is pumped from a stirred isothermal tank via a booster pump and a high pressure pump into the plant.
- Preheating: The biomass is heated up to preheat it and to hydrolyze larger biopolymers into smaller molecules.
- Salt separation: Removal of dissolved salts by precipitation through heating up the feed stream to supercritical temperatures.
- Gasification: Gasification of the biomass to methane and carbon dioxide in a fix bed reactor filled with a catalyst under near critical or supercritical conditions.
- Cooling and pressure regulation: After the reactor the product stream is cooled to about 50 °C. The pressure is regulated via and control valve and a relief valve where the product stream is expanded to atmospheric pressure.
- Phase Separation of the gaseous and the aqueous phase. The gaseous product then pass a condenser to remove water vapour.
- Analysis and exhaust gas combustion: Online GC analysis of the gaseous products and combustion of inflammable gases before venting into the air.
Sapphire Window Cell
- Pmax 35 MPa
- Tmax 400 °C
- Sapphire windows
- Optical width 8 mm Ø
High-Pressure Reaction Cell / DRIFTS set-up
- Sample volume: approx. 80 mg catalyst
- Pmax : 11 Bara
- Tmax: 500 °C - heating rates: up to 5 K / min
- Window: ZnSe (transparent from 20'000 cm-1 to 455 cm-1)
- On line analysis of the reactant and product gas composition possible with QMS
High Pressure Autoclave
- Volume = 422 ml
- Pmax = 325 bar
- Tmax = 500 °C
- Online detection of temperature and pressure
The vessel is built in a continuous flow system with the following characteristics:
Fed with a pulseless HPLC pump capable of 1-10 mL/min Preheater capable of heating the feed to 350C, maintaining the fluid at slightly subcritical conditions so that precipitation does not occur before the Salsan vessel. Separate heater controls for the top and bottom of the vessel. In normal operation, the bottom zone is kept at a lower temperature to allow brine to accumulate in this zone. The top zone is kept supercritical for salt separation. Online monitoring of conductivity for indication of salt removal efficiency. The vessel is constructed so that fluid enters in the top through a dip-tube. The fluid flow reverses as it is heated to supercritical conditions. Meanwhile, salts precipitate either as solids or as a brine and settle to the bottom of the vessel.
Catalytic reactor for in-situ XAS under supercritical water conditions
Batch Hydro I + II
- Volume approx. 30 mL
- Pmax 40 MPa
- Tmax 550 °C
- Possibility of addition of inert gas (larger pressures possible)
- Heating by immersion into fluidized sand bath (heat up rates 5 – 40 K / min)
- Quenching after reaction by immersion into water bath
- No online analysis of reactants and products possible during reactio
Reactor Stainless steel, channel height = 4 mm Maximum heating temperature = 750°C
Gas Sampling Movable stainless steel sampling capillary, internal diameter = 0.5 mm, external diameter = 0.8 mm Capillary enters reactor through high temperature septum port Capillary is placed directly above catalyst plate Electrical step motor is coupled to a linear positioning system (accuracy < 0.1 mm) Heated transfer line to GC and MS
Setup Control LabVIEW™ program to control the step motor, the mass flow meters and the controllers of the different heaters
- Spectral range: 900 - 1700 nm
- Detector: Indium Gallium Arsenide
- Array format: 320 x 256
- Pixel: 30 x 30 microns
- Frame rate: 30 Hz
- Temperature range: 20 - 1200°C