Pulp Slurry and Erosion: Why Careful Valve Selection Is Crucial in the Paper Industry

In the modern paper industry, companies face a challenge: you process pulp slurry, chemically aggressive media, and fiber-rich flows — all of which place high demands on your valve technology. When you do not use a properly selected valve, you risk wear, erosion, unplanned downtime, and high maintenance costs. At Bray Controls Benelux, we specialize in valve technology, including specific solutions for paper mills. In this blog, we explain why the right valve selection is crucial, which factors you should consider, and which products from our portfolio can help you achieve optimal performance.

Why is valve selection so important in the paper industry?

The paper and pulp production process consists of several stages: pulp manufacturing, pulp bleaching and washing, and fiber recycling. In all of these, pulp slurry (a mixture of cellulose fibers, water, chemicals, and often solid particles) plays a central role. Because this slurry is often abrasive (fibers and solid particles move at high speed through pipes), erosion and wear occur. Erosion causes seals, valve seats, and internal surfaces to wear down more quickly, resulting in leaks, incomplete shut-off, and ultimately production downtime.

Additionally, paper mills use chemicals (such as caustic soda, acids, peroxide, or chlorine dioxide) that are highly corrosive. The combination of an abrasive and chemically aggressive medium means that you cannot simply use a standard valve; you need a solution that is resistant to both erosion and corrosion.

Furthermore, downtime in a paper mill is extremely costly, as energy, raw materials, and production time are lost. That is why a reliable valve is essential.

Key process stages in the paper industry

Below are three typical processes within paper mills where valves play a key role:

1. Pulp slurry transport and preparation

During pulp preparation, wood or plant material is processed into pulp. This pulp contains fibers and slurry components that need to be moved through the system. This means that valves in this phase are often exposed to high loads from fibers, solids, and chemicals. A good example is the Kraft process, where pulp, white liquor, green liquor, or black liquor are handled. Therefore, a valve must have a robust design.

2. Bleaching, washing, and rinsing pulp

When pulp is bleached, chemicals such as chlorine dioxide, peroxide, or ozone are used. Because these chemicals can quickly corrode the valves that handle the pulp, it is important to carefully select the materials and valve type.

3. Recycling and fiber reuse

In paper and pulp recycling, slurry often contains fibers, non-paper particles, metal fragments, or other solids. Here, knife gate valves often perform best due to their large bore and ability to handle fiber-rich media.

What should you consider when selecting a valve?

When selecting a valve for the paper industry, it is important to take the following criteria into account:

• Material and corrosion resistance: For chemically aggressive or particle-laden media, choose stainless steel, duplex steel, special coatings, or linings.
• Abrasive loading: If fibers or solid elements are present in the medium, the valve must be designed for wear resistance (e.g., hardened discs, seats, or replaceable components).
• Type of operation (isolation vs. control): Does the valve need to fully shut off, or must it modulate flow? Slurry transport typically requires on/off isolation, while washing and bleaching may need control valves.
• Flow path and geometry: Minimal pressure drop and no dead zones help limit erosion and wear.
• Maintenance and service life: Modular designs, replaceable components, and easy inspection reduce maintenance time and minimize downtime.
• Actuation and automation: For frequent use or integration into automated processes, an actuator is recommended for safe and fast operation.

Relevant valve products from Bray Controls Benelux

At Bray Controls Benelux, you will find a wide range of valves, actuators, and accessories specifically suited for demanding industries such as pulp & paper. Below are a few examples:

• Series 30/31 Butterfly Valve – These butterfly valves are suitable for isolation applications with a resilient seat.
• Series S19/S19L Ball Valve – The ideal ball valve for pulp and paper transfer applications.
• TriLok® Triple Offset Butterfly Valve – A zero-leakage butterfly valve perfectly suited for use in paper mills.
• VM Series Knife Gate Valve – With its robust design, this valve is ideal for the paper industry.

By choosing the right products from our range, you ensure your paper mill is resistant to erosion, wear, and chemical stress.

Why choose Bray Controls Benelux?

At Bray Controls Benelux, you benefit from:

• Specialization in valve technology for demanding industries such as pulp & paper
• A comprehensive product portfolio, allowing you to rely on a single supplier for butterfly valves, ball valves, knife gate valves, actuators, and controls
• Regional presence in the Benelux (Heerhugowaard) with local stock and service
• High quality, reliability, and expert support in valve selection, essential for processes involving pulp slurry and erosion risk

Conclusion

In the paper industry, processing speed and continuity are essential. A poorly chosen valve can lead to erosion, wear, production loss, and high maintenance costs. With a thoughtful selection based on material, valve type, process stage, and maintainability, you are better prepared for the challenges of pulp slurry, chemicals, and fiber-rich flows.

Bray Controls Benelux provides both the products and the expertise to help you meet these challenges. By using our high-quality valves, you can optimize your process, minimize downtime, and maximize reliability.

Learn more about Bray’s solutions for the paper industry on our applications page.

Would you like advice on which valve best suits your paper mill? Contact us for tailored technical advice!