Eka® bleaching services

Eka Engineering specialize in the design and supply of chlorine dioxide plants and equipment to the pulp and chemical industries

Eka Engineering is the engineering and contracting division that is part of our bleaching chemicals business. We specialize in the design, build and supply of chlorine dioxide plants and equipment to the pulp and chemical industries.

We offer completely new turnkey plants, the upgrade and repair of existing plants and comprehensive services for large-scale production and application of chlorine dioxide; for both vacuum and atmospheric technology plants. Our experienced personnel, world class technology and project management capabilities provide customers with a significant advantage for their operations. We operate globally and provide customers with quick and personal service.

Our offering - Expert Services for Optimal Plant Performance

• New ClO₂ generators and rebuilds

• Process optimization and troubleshooting

• Inspections and maintenance

• Trainings and startup support

• Spare parts service

• R&D support

Plant Ribas Brazil — Our latest project; building an Integrated Manufacturing Model in Ribas do Rio Pardo in 2024

>200 installations

Having completed over 200 installations globally, we bring a wealth of experience and knowledge to every tailored project.

Lowest AOX

We are proud to offer the lowest levels of AOX, or halogenated organic compounds, ensuring a cleaner and more sustainable solution.

Optimized Consumption

Our advanced integration with pulp mills ensures that we minimize losses and optimize resource use.

Costsaving Efficient

Integrating our processes with the mill's operations reduces waste and maximizes efficiency, helping our customers become more cost efficient.

Safe & Stable Operations

We deliver high-standard safe and stable installations based on well-established industry practices and cutting-edge innovations.

Eka Engineering specialize in the design, build, and supply of chlorine dioxide plants and equipment

We offer turnkey plants, upgrades, repairs, and comprehensive services globally with experienced personnel, world-class technology, and project management capabilities.

We offer best available techniques (BAT) for safe, effective and sustainable chlorine dioxide production

We design systems to meet your mill's specific needs and requirements. We recommended technologies using methanol (CH₃OH) or hydrogen peroxide (H₂O₂) as reducing agents, based on their high yield, low cost and good fit with the mill's chemical systems.

We offer processes that produce chlorine dioxide (ClO₂) without formation of elemental chlorine (Cl₂). These offer a significant advantage for our customers, dramatically reducing the level of chlorinated organic compounds (AOX) in their pulp mill effluent. While vacuum processes are more complex compared to atmospheric processes, they are preferable for larger ClO₂ demands. However, the HP-A process is frequently used, especially when retrofitting older installations.

Processes

On-Site ClO₂ Production

The formula to produce (ClO₂) is to reduce sodium chlorate (NaClO₃) in an acidic solution. The different processes are distinguished from each other by use of different reducing agents and acids for reducing sodium chlorate (NaClO₃), to chlorine dioxide (ClO₂) and respective biproducts.

NaClO₃, to ClO₂ and respective biproducts.

The SVP (Single Vessel Process) chlorine dioxide process family consists of several similar processes based on the same equipment configuration. It is relatively easy to switch from one to the other. The most common chemicals for SVP processes is sulphuric acid for acidification and methanol as reducing agent to produce ClO₂.

For more details see below or download our broschures.

SVP-LITE^® Process

The SVP chlorine dioxide process consists of numerous variations where LITE is the simplest one. Reaction, crystallization, and gas-liquid separation all take place inside the SVP generator, hence the name single vessel process (SVP). The process operates in vacuum to ensure a high concentration and yet safe level of chlorine dioxide. The by-product stream consists of an aqueous solution of acidic sodium sesquisulphate which is generally used for acidification in the pulp mill.

SVP-SCW Process

The SVP-SCW is a modified version of the LITE which adds another washing step for the by-product stream. The advantages of washing sodium sesquisulphate is to recover an acidic filtrate stream of sulphuric acid, reducing the overall H₂SO₄ consumption by approximately 17%. Moreover, the salt after the second wash is neutral sodium sulphate which is desired in the mill’s evaporation plant for caustic make-up, reducing the waste generation to almost zero.

HP-A^®Process

HP-A is one of the newest processes by Nouryon. The proprietary technology has several advantages over earlier atmospheric chlorine dioxide processes and is commonly rebuilt from older Mathieson processes. The processs utilizes sulphuric acid for acidification and hydrogen peroxide as reducing agent to produce ClO₂.

Integrated Manufacturing Model

The Integrated Manufacturing Model concept lowers the carbon footprint and enhances chemical production efficiency while reducing transportation needs. Nouryon recently completed the construction of sodium chlorate and hydrogen peroxide facilities in Ribas do Rio Pardo, Brazil, supporting the pulp mill that began production in late 2024.

Integrated Manufacturing Model - A state-of the-art facility located next to a customer's pulp mill, often inside the perimeter fence.

With a full-scale Integrated Manufacturing Model in place, our customers benefit from a tried, tested and successful concept managed and operated – on site, 24/7 – by our experts who ensure consistent production and delivery of chemicals needed to operate the mill.

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Advancing Environmental Sustainability through Innovative Technologies

Our technology ensures the lowest levels of AOX in the industry, demonstrating our commitment to reducing harmful emissions. Additionally, our process is optimized for efficiency and operates primarily within a closed-loop system, minimizing waste, promoting sustainability, and reducing overall environmental impact.

Why does ECF bleaching by Eka Engineering technology make good environmental sense?

Following the abandonment of chlorine as a bleaching agent due to environmental considerations, two technologies were developed. The first is Elemental Chlorine Free (ECF) and the second is Total Chlorine Free (TCF). The distinguishing factor between the two processes is the use of chlorine dioxide, which is used in ECF but not TCF. To compensate for the lack of chlorine dioxide, TCF will either add higher dosages of hydrogen peroxide, or supplement the process with ozone.

In 2024, ECF pulp constituted 93% of the world share of bleached chemical pulp market. TCF, although decreasing slightly in market share, has remained at approximately 5% of the bleached chemical pulp market.

Learn more in the research paper Environmental systems analysis of alternative bleaching sequences with focus on
carbon footprint by Pia Jour, Karin Halldén and Eva Wackerberg.

Service and spare parts

Our spare parts service will help ensure your plant availability is maximized and any downtime is minimized.
We deliver all parts rapidly and reliably using our extensive supply chain and global logistics network.

For quality assurance, we deliver spare parts from the original supplier whenever possible. Some typical spare parts we provide include pump parts, instruments, valves, and filter inserts.

Optimization

Assessment of chemical yield on sodium chlorate, reducing agent and acid
Chlorine dioxide production capacity tests
Saltcake removal & utilization
Vent system emissions recovery
Investigations of emissions to both air and sewers
Advanced process control implementation

Operational Support

Our experts are invaluable in troubleshooting and solving mill problems. With knowledge of kraft, mechanical and sulfite pulp bleaching and associated processes our engineers have helped solve pulp brightness problems, scaling issues and environmental concerns

Remote or on-site troubleshooting
Applied Kepner-Tregoe methods
Inspection on material conditions
Root cause analysis
Maintenance planning assistance
Inspection and advice on sodium chlorate, sulfuric acid, methanol, hydrogen peroxide and chlorine dioxide storage
Investigations of process and production limitations in the chlorine dioxide plant

Process safety

Participation in safety audits and risk analysis at the chlorine dioxide plant
Interlock checkouts for Process Safety Management (PSM) program
Process Hazard Analysis (PHA) re-validation for methanol, chlorine dioxide, turpentine, ammonia and non-condensable gas (NCG) systems
Supporting documentation / process safety information / Management of Change (MOC) process verification
PHA Facilitation & OEM Process Expert

Training

Our experts are often asked to deliver customer-specific bleach plant operations training. In these sessions, we train mill personnel how to evaluate, troubleshoot and optimize their own process and often present case studies of real situations encountered. Training is onsite and is beneficial to all personnel – operators, engineers and foremen.