Industries / Bioethanol
EFFICIENT BIOETHANOL DEHYDRATION
Conventional bioethanol dehydration using molecular sieves or azeotropic distillation is often a compromise in energy consumption, process complexity or operating costs. We offer a more effective alternative: with our pervaporation technology, bioethanol can be dehydrated continuously to below 0.1 wt%.
Purity without compromise
In bioethanol production, every penny per litre counts. Yet, many operators accept the limitations of conventional methods: molecular sieves operate discontinuously and require complex regeneration phases, while azeotropic distillation processes often rely on additives to overcome the azeotropic point.
Today’s market demands more. Pharma-grade ethanol and food-grade bioethanol require absolute purity. Residual additives or unwanted by-products such as aldehydes – which can occur in molecular sieves – are unacceptable. DeltaMem’s pervaporation technology offers a straightforward alternative. Our process requires no third component and generates no by-products, delivering bioethanol of the highest quality for the pharmaceutical and food industries.
Debottlenecking and direct dehydration
DeltaMem technology does more than replace conventional dehydration methods. It can also enhance the performance and capacity of existing bioethanol plants.
- No evaporation required: We can process liquid, water-rich ethanol (even exceeding 10% water content) directly. This saves the energy that would typically be required for the complete evaporation of ethanol (as needed for molecular sieves).
- Debottlenecking existing plants: By integrating DeltaMem units into existing installations, regeneration side streams from molecular sieves can be treated separately, increasing overall plant throughput without major modifications or investment in additional dehydration capacity.
- Continuous operation: Our pervaporation operates continuously under stable process conditions, simplifying plant operation and process control.
- Electrification for lower emissions: Since our process operates at relatively low temperatures, it can be combined with heat pump technology. This enables fully electrified dehydration systems, reducing dependence on fossil fuels and supporting the transition to low-carbon bioethanol production.
Cost advantage: reduced energy consumption
For a bioethanol stream with 8% water content, our pervaporation requires only 0.14 kg of steam per kg of dry ethanol. Compared to thermal processes that must repeatedly evaporate and condense the entire volume, this offers an unbeatable cost advantage per litre of final product.
Case study: recovering value from process side streams
In the production of food-grade bioethanol, side streams are generated that are often treated as waste. For one of our clients, we supplied a pervaporation skid specifically designed to dehydrate these streams, using the dry solvent as biofuel. Prior laboratory testing confirmed the long-term stability of our membranes when exposed to complex mixtures containing by-products such as fusel oils, transforming a disposal challenge into a valuable product stream.
Purity for pharmaceutical applications
While molecular sieves can lead to formation of aldehydes, our process remains inherently clean. This makes DeltaMem the preferred choice for the dehydration of pharma-grade ethanol. No trace of cyclohexane, no thermal degradation products – simply efficient removal of water, delivering high-purity ethanol.
Frequently asked questions
Can DeltaMem increase the capacity of molecular sieve plants?
Yes. Debottlenecking existing molecular sieve systems is one of our core strengths. By integrating pervaporation units into the regeneration cycle, we process the regeneration side streams separately, increasing overall plant capacity and improving energy efficiency without the need for major modifications or investment in additional dehydration equipment.
What are the space requirements for a pervaporation plant?
Our systems are designed with a compact footprint. As they do not require large distillation columns or large regeneration vessels, DeltaMem systems can often be integrated into existing plants where installation space is limited.
Are the membranes stable when exposed to fusel oils?
Yes. Through long-term tests and large-scale applications in the food-grade ethanol sector, we have demonstrated that our membranes remain stable and maintain their separation performance even when processing complex mixtures containing by-products like fusel oils.
How does pervaporation differ from molecular sieve dehydration?
Unlike molecular sieve processes, pervaporation operates continuously and requires no regeneration cycles. Furthermore, it can directly process liquid, water-rich ethanol with a water content of over 10% without requiring the prior evaporation of the entire stream. This significantly reduces energy consumption while simplifying plant operation.