As an experienced provider of turnkey caustic soda plant solutions, we share below a realistic timeline based on industry practice and our project experience.
Typical Project Timeline for a Turnkey Caustic Soda Plant
In general, the construction period of a turnkey caustic soda plant ranges from 8 to 18 months, depending on capacity, technology route, and local conditions. The entire project can be divided into several key stages.
1. Project Planning & Feasibility Study (1–2 Months)
The project planning and feasibility study stage is the foundation of the entire turnkey caustic soda plant. At this stage, we work closely with clients to transform an initial investment idea into a technically and economically viable project concept.
Key Scope Definition
During this phase, we assist clients in defining all critical technical and commercial parameters, including:
Plant capacity
Daily production capacity is typically expressed in TPD (tons per day) of NaOH. Capacity selection directly affects equipment size, power consumption, capital expenditure, and future scalability.
Product form
Depending on downstream market demand, the plant may produce:
Liquid caustic soda (30%, 32%, or 50%)
Caustic soda flakes
Caustic soda pearls
Each product form requires different evaporation, solidification, and packaging systems.
Raw material quality
The quality of brine (salt source) is a decisive factor in membrane cell electrolysis performance. We evaluate:
Salt purity and composition
Presence of calcium, magnesium, sulfates, and organic impurities
Availability and logistics of raw salt supply
Local utilities and infrastructure
Stable supply of electricity, process water, cooling water, steam, and compressed air is essential. Power cost, in particular, has a major impact on operating expenses in caustic soda production.
Environmental and safety requirements
We assess local regulations related to:
Chlorine and hydrogen handling
Wastewater discharge
Solid waste disposal
Occupational safety and hazardous area classification
Feasibility Analysis Benefits
A professional feasibility study helps to:
Estimate total project investment and operating costs
Compare different technology routes and capacity options
Identify potential technical and regulatory risks
Optimize plant configuration before detailed engineering begins
2. Basic Engineering & Detailed Design (2–3 Months)
Once the feasibility study is approved and the technical route is confirmed, the project enters the engineering design phase. Today, membrane cell technology is the most widely adopted solution due to its high efficiency, low energy consumption, and compliance with global environmental standards.
Process Engineering
At this stage, we develop complete process documentation, including:
Process Flow Diagrams (PFD) showing overall material and energy balance
Piping and Instrumentation Diagrams (PID) detailing valves, instruments, and control loops
Process descriptions and operating philosophies
These documents form the technical backbone of the entire plant and guide all downstream activities.
Equipment & System Design
We prepare detailed specifications for all major and auxiliary equipment, such as:
Membrane electrolyzers
Brine purification reactors and filters
Heat exchangers and evaporators
Pumps, tanks, and pipelines
Chlorine drying and compression systems
Hydrogen treatment and safety systems
Each piece of equipment is selected to ensure long service life, operational stability, and ease of maintenance.
Plant Layout & Civil Design
A rational plant layout is essential for:
Safe material flow
Efficient operation and maintenance
Future expansion possibilities
We design:
General plant layout (GAD)
Building structures and foundations
Pipe racks and access platforms
Hazardous area zoning
Electrical, Instrumentation & Automation
Modern caustic soda plants rely heavily on automation. We provide:
Electrical single-line diagrams
Instrument lists and control logic
DCS or PLC-based automation systems
Energy monitoring and safety interlocks
A well-executed engineering design phase ensures stable operation, low energy consumption, and full compliance with international standards, while minimizing on-site rework and schedule delays.
3. Equipment Manufacturing & Procurement (3–5 Months)
As a turnkey caustic soda plant provider, we take full responsibility for equipment manufacturing and global procurement, ensuring quality consistency and delivery schedule control.
Core Equipment Manufacturing
Key systems manufactured or sourced during this phase include:
Electrolyzers (membrane cell units)
These are the heart of the plant, determining energy efficiency, current efficiency, and product purity.
Brine purification system
Includes chemical dosing units, clarifiers, filters, and polishing systems to meet strict membrane cell requirements.
Evaporation and concentration system
Multi-effect evaporators are designed to reduce steam consumption and achieve target NaOH concentration.
Flaking or prilling units
For clients producing solid caustic soda, specialized solidification systems are integrated into the process line.
Chlorine and hydrogen handling systems
These include dryers, compressors, absorbers, and safety devices designed according to international safety codes.
Parallel Project Execution
One major advantage of turnkey project execution is parallel scheduling. While equipment is being manufactured, civil works and site preparation can proceed simultaneously, effectively shortening the total project duration.
Equipment lead time varies depending on:
Plant scale
Degree of customization
Local content requirements
Careful procurement planning is essential to avoid bottlenecks during installation.
4. Civil Construction & Installation (2–4 Months)
The construction and installation phase transforms engineering drawings into a physical operating plant.
Civil Construction
Civil works typically begin while equipment manufacturing is ongoing and include:
Foundations for heavy equipment
Structural steel and concrete works
Plant buildings and control rooms
Utility corridors and drainage systems
Proper civil preparation ensures smooth equipment installation and alignment.
Mechanical & Electrical Installation
After equipment arrival, installation activities include:
Mechanical erection of electrolyzers, tanks, and evaporators
Piping fabrication and installation
Electrical cable laying and termination
Instrument installation and loop checking
Integration of control systems
Safety & Quality Control
Throughout this phase, we implement strict:
Construction safety management
Quality inspection and testing procedures
Compliance checks against design and standards
Well-organized construction management helps compress installation time without compromising safety or quality.
5. Commissioning, Trial Run & Training (1–2 Months)
The final stage before handover is commissioning and startup, where the plant transitions from construction to stable operation.
Commissioning Activities
We conduct:
Cold commissioning: system checks without chemicals
Hot commissioning: introduction of brine and utilities
Functional testing of all subsystems
Safety and interlock verification
Trial Operation
During trial runs, the plant is operated under increasing loads to:
Verify production capacity
Confirm product quality and purity
Optimize energy consumption
Validate process stability
Any issues identified during trial operation are corrected promptly to ensure reliable long-term performance.
Operator Training & Handover
We provide comprehensive training covering:
Process operation and control
Routine maintenance procedures
Emergency handling and safety protocols
Complete technical documentation and as-built drawings are delivered as part of the turnkey handover.
