Our STT® Technology
STT® technology significantly increases reaction rates where momentum, heat, or mass transfer is a challenge. A significant benefit of the STT® technology is that optimization can be determined on the bench scale (Magellan® series), which easily scales through the pilot production (Innovator® series) and then into the commercial scale.
STT® reactor technology for chemistry applications has been developed and thoroughly tested over Eight (8) years. The key component of the process is a small reactor that produces a chemical process intensification system, resulting in significant time and cost savings over traditional chemical processing methods.
Some of the advantages that the STT® Reactor technology brings include:
- Rate enhancement
- Improved conversion
- Selectivity enhancement
- Continuous processing versus batch
- Improved temperature and reaction environment control
- Reduced catalyst consumption and solvent use
- Reaction of normally immiscible materials
- Mixing of materials with large relative viscosities
- Improved safety in handling toxic and explosive materials
- Rapid and efficient cleaning
- Small reactor foot print compared to conventional reactors. Accompanying photograph of a 1,000ML STT® Reactor Assembly for biodiesel duty illustrates size.
4Rivers has the advantage of previous work done where the STT® Technology has been developed, tested, and demonstrated in applications for biodiesel, bioethanol, specialty chemicals, pharmaceuticals and pharmaceutical precursors, agrochemicals, deagglomeration, fine particle synthesis, basic chemicals, materials used for electronic applications and blending. Named STT® after its spinning tube-in-tube design, the system’s unique two-dimensional flowing film high shear produces significant time and cost savings over traditional volume-based production methods by minimizing mass transfer problems. STT® technology allows us to avoid serious inefficiencies resulting from uneven mixing, temperature gradients, scale-up constraints, and excessive waste which are prevalent in most conventional manufacturing processes. With its broad applicability and flexibility, STT® technology and reactors allow us to accelerate the rates of chemical reactions of solid, liquid, or gaseous materials by up to three orders of magnitude and to increase yields by up to seven-fold, control the quality of chemical processes in real-time, and dramatically decrease the time required for manufacturing scale-up.
In summary and specifically for production of biodiesel:
The STT® system is a true continuous processing system and employs a high shear flowing film, rather than a batch mixing approach, for reacting the feedstock oil with methanol using a catalyst to make biodiesel. Reactants enter the system at one end of the narrow annular zone between the stator and the rapidly spinning rotor, and are quickly and thoroughly mixed by high shear forces in a few milliseconds. The transesterification chemistry is essentially complete in less than a second. The temperature of the mixture is controlled precisely by the heat exchanger jacketing the stator. Sensors for measuring temperature, monitoring reaction process, or gathering other information relative to the manufacturing process can also be incorporated along the rotor/stator assembly to dynamically monitor the reaction process.
Two material entry ports and the product exit port are shown in the figure. The reaction takes place in the annular zone between the rotor and the stator. The highly-effective type of flow that occurs in the STT® system is not achieved in other flow-through reactor systems, even those that also employ a rotor-stator design or cavitation. This flow pattern is a result of a proprietary and patented process system design.
The STT® Biodiesel Production Unit is better operationally for the following reasons
- Less expensive, more efficient, safer, and easier biodiesel production process.
- Dramatically reduced biodiesel total conversion time of less than one second. (Conventional plants typically require from 90 minutes to more than 24 hours total production time.)
- More efficient transesterification process that produces negligible soap and requires less downstream processing.
- Multi-feedstock flexibility and ability to switch rapidly between alternative feedstocks (a few minutes, rather than days for conventional production units).
- Consumes less catalyst and uses a lower-cost catalyst.
- Requires less energy.
- Better for the environment since it does not produce contaminated production waste-water.
- Production unit has fewer moving parts and overall components making it more durable, requiring less maintenance and lasting longer.
Practical applications of the STT® Technology to date
- Research and Development Facilities operated by the US Environmental Protection Agency
- Research and development into perfume and fragrances manufacturing
- A 50 million gallon per annum Biofuels project under construction in the US