
Project Case Study
News ⋅ Project Case Study: EVA Plant Debottlenecking
EVA Plant Debottlenecking Case Study: 35% Capacity Increase
How can an EVA plant increase capacity without a full rebuild?
ECI Group helped an EVA producer in China achieve a 35%+ capacity increase by implementing our proprietary Hybrid Autoclave Reactor Extension (HARE™) technology. The project also improved product quality, operational flexibility, and reactor performance—with minimal downtime.

Project Summary
- Process: Autoclave
- Location: China
- Original Capacity: 72 ktpa
- New Capacity: 100 ktpa
- Capacity Increase: >35%
- Technology Used: HARE™ (Hybrid Autoclave Reactor Extension)
- Downtime: 30-day shutdown
- Start-up, Product Qualification and Performance Tests: 1 week
What Is Plant Debottlenecking?
Plant debottlenecking is the process of removing production constraints to increase throughput, efficiency, and product flexibility—without building a new facility.
In high-pressure polyethylene and EVA plants, this often focuses on improving reactor conversion, throughput, and performance while maintaining safety and product quality.
Client Challenge
The client approached ECI with a view to increase the production capacity of their autoclave plant originally commissioned in 2016. They specified the following key success parameters:
- Increase conversion to maximize production
- Maintain or enhance product properties and qualities
- Minimize downtime during implementation
- Maintain or improve safety performance
- Improve high-pressure recycle (HPR) unit performance
ECI Group’s Solution
Following a detailed feasibility study, ECI Group identified that installing a hybrid reactor extension (HARE™) would deliver the best outcome.
Why HARE™?
HARE™ technology enables:
- Increased reactor conversion
- Higher throughput within existing infrastructure
- Improved product consistency
- Enhanced operational flexibility
The HARE™ provides these benefits whilst avoiding the cost and downtime associated with a major plant overhaul.
Engineering and Execution Approach
- ECI Group conducted an in-depth plant assessment, evaluating all potential debottlenecking strategies with associated considerations for capital costs, plant downtime and operating costs.
Key deliverables included:
- Process & Instrumentation Diagrams (P&IDs)
- Long-Lead Item (LLI) specifications for early procurement
- Laser scanning of the plant
- Full 3D digital model development
Working with the client’s preferred local EPC contractor:
- ECI Group designed all high-pressure systems
- EPC partner handled low-pressure plant design
- Long-lead equipment orders were placed early
- Vendor data was integrated into a shared 3D model
To minimise impact on operations:
- Installation completed in 30 days, the majority of which took place during normal plant operation
- Start-up and performance testing completed within one week
- Rapid achievement of design capacity and product quality
The upgraded plant restarted successfully in November 2022.
Results and Benefits
Key Outcomes
- >35% increase in plant capacity
- Improved EVA product quality and consistency
- Enhanced reactor and process performance
- Minimal disruption to operations
- Fast return on investment
Key Success Factors
- Deep expertise in high-pressure LDPE/EVA technologies
- Early engagement with critical equipment vendors
- Integrated 3D modelling and design coordination
- Strong collaboration between client, EPC, key vendors, and ECI Group
This project highlights how advanced engineering and proprietary technology can unlock significant hidden capacity in existing EVA plants.
By leveraging our proprietary HARE™ technology and a highly coordinated execution strategy, ECI Group enabled a step-change in production performance—without the cost or downtime of building new infrastructure.
Looking to Increase EVA Plant Capacity?
Contact ECI Group’s Consultancy Services team to explore how debottlenecking, reactor upgrades, and high-pressure process optimisation can help you maximise production and profitability.