15/06/2026
💡 Can ESMIL membrane technology be used to concentrate monomer-containing process streams?
This was the challenge presented to us by a customer operating in the advanced plastics recycling and biotechnology sector. Today, we can confidently say that the answer is: yes. ✅
The project objectives were:
1️⃣ Increase the concentration of sodium sulphate (Na₂SO₄)
2️⃣ Reduce the level of dissolved salts
3️⃣ Produce a monomer fraction meeting the quality requirements for sale
To evaluate the process, we carried out a staged pilot testing programme using nanofiltration (NF) and reverse osmosis (RO).
▶ NF was used to concentrate sodium sulphate and monomer-rich streams
▶ RO was applied to polish the NF permeate by reducing dissolved salt content
The results achieved:
✔️ Recoveries of up to 76% for NF and up to 84% for RO
✔️ Conductivity increased from approximately 16,370–22,840 μS/cm to 50,960–59,310 μS/cm during NF concentration
✔️ RO permeate conductivity reduced from approximately 350 μS/cm to around 70 μS/cm
✔️ Effective sodium sulphate concentration combined with significant dissolved salt reduction through RO polishing
Following the successful trials, the customer moved forward with a dedicated 1.8 m³/h pilot system designed and manufactured by ESMIL using 4040 membrane modules. The mobile skid platform can operate with UF, NF and RO membranes, supporting further process development and optimisation. 📊
👉 It quickly became clear that the project had potential far beyond the pilot stage. The experience gained from operating the pilot unit paved the way for the next scale-up phase, and we are now developing a full-scale containerised membrane system based on 8040 membrane modules.
This project reflects the way we approach membrane solutions at ESMIL. We start by validating the technology under real operating conditions and then scale the process step by step towards full industrial implementation.
As a result, the final solution is based on real process data and proven performance, ensuring it is tailored to the customer’s application rather than relying solely on design assumptions.