Electrified Distillation Explained: The Science Behind VoltaSplit™

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Introduction

Distillation is a cornerstone process in industries such as chemicals, oil & gas, pharmaceuticals, and food & beverage. While conventional distillation has been used for centuries, it is energy-intensive and often relies on energy produced from fossil fuels.

This not only drives up operating costs but also contributes significantly to greenhouse gas emissions.

Sulzer’s VoltaSplit™ technology introduces a new way forward: electrified distillation, offering a smarter way to run this essential process. But what exactly is electrified distillation, and how does VoltaSplit™ make it possible? Let’s break down the science behind this innovative approach.

Electrified Distillation Explained

For a distillation or stripping column to operate properly, the bottom must be kept warmer than the top. Traditionally, this is achieved by supplying heat to the reboiler (using steam, hot oil, or fired heaters) and removing heat at the condenser (with cooling water or other utilities).

VoltaSplit™ takes a smarter approach. Instead of wasting the latent heat in the column’s overhead vapor by condensing it in the top condenser, VoltaSplit™ uses electrically powered compressors to raise its pressure and condensation temperature. This compressed vapor then serves as the heating medium for the reboiler at the column bottom.

By recycling energy already present in the process, VoltaSplit™ can reduce the need for external utilities, helping to lower operating costs and CO₂ emissions.

How VoltaSplit™ Works – Step by Step

1. Overhead Vapor Recovery – The vapor leaving the top of the column contains substantial latent heat.

2. Vapor Compression – Electrically driven compressors increase the vapor’s pressure, raising its condensation temperature.

3. Heat Reuse in the Reboiler – The compressed vapor is condensed in the reboiler, releasing heat that provides the necessary boiling duty at the column bottom.

4. Normal Column Operation – Part of the distillate is recycled as reflux to maintain separation, while the rest is withdrawn as product.

   
   

To support reliable operation, auxiliary equipment may be included:

• Startup reboiler (powered by steam or electricity), used during start-up and for process control.

• Trim condenser, used during shutdown or special operating conditions, powered by conventional utilities.

  
  

This configuration makes VoltaSplit™ both flexible and robust for industrial-scale operation.

Key Advantages of VoltaSplit™

• Seamless Integration – Can be retrofitted into existing distillation columns or incorporated into new designs.

• Electrified Operation – Uses electricity as its main energy source, enabling decarbonization when paired with renewable power.

• Advanced Controls – Ensure smooth and efficient operation together with rotating equipment.

• Proven Performance – Demonstrated reductions in energy consumption, operating costs, and CO₂ emissions.

  
  

Economic and Environmental Benefits

• Energy Efficiency – VoltaSplit™ can reduce energy use by 50% to 95%, with exact savings depending on column design and operating conditions.

• Lower Operating Costs – Lower demand for utilities such as cooling water and steam, which can reduce overall operating costs.

• Reduced CO₂ Footprint – Direct CO₂ emissions can be reduced to near zero when powered by renewable electricity.

• Rapid Payback – In many cases, return on investment can be achieved in under two years, depending on local energy costs.

• Eligibility for Incentives – Many installations qualify for grants, tax credits, or preferential financing.

  
  

The Future of Distillation

As industries seek to decarbonize while maintaining profitability, Sulzer’s VoltaSplit™ offers a future-proof solution. By recycling energy within the column itself and running on electricity, VoltaSplit™ combines efficiency, sustainability, and cost savings in one technology.

Ready to modernize your distillation process? Contact Sulzer Chemtech to learn how VoltaSplit™ can help you achieve your efficiency and sustainability goals.