In Nordic climates, effective insulation is not a luxury, it’s a necessity. Rockwool, a global leader in stone wool insulation, creates high-performance thermal barriers by spinning molten rock into fiber, similar to candy floss. This process starts with melting sand and basalt at extremely high temperatures, powered by an advanced Oxyfuel combustion system.

In the production of stone wool, Rockwool’s Oxyfuel combustion system requires highly precise control of both the pressure and flow of oxygen and natural gas. Achieving the ideal flame temperature for melting raw materials is critical, as any deviation can result in inefficient combustion, increased energy consumption, or even system instability.

Key challenges

• Pressure Control: Maintaining consistent pressure is crucial to achieving optimal combustion conditions. Variations in pressure can lead to uneven fuel consumption, resulting in fluctuating temperatures that affect the quality of the stone wool produced.
• Flow Regulation: Accurate flow control is essential for managing the mix of oxygen and natural gas. An improper balance can lead to incomplete combustion, higher emissions, and wasted energy.
• High Temperature Handling: The Oxyfuel burners operate at extreme temperatures, requiring valves that can withstand these harsh conditions while maintaining precise control.

For this furnace application, melting sand into insulation material requires the perfect mix of natural gas and oxygen. To achieve this, the regulator maintains a stable pressure before the flow meters and at the valve inlet, ensuring accurate flow control through the Ramén KSC Ball Sector Control Valve. This precise regulation is essential for getting the correct mixture of natural gas and oxygen at the burner, which is critical for efficient and consistent melting.

To address these challenges, we have supplied a complete valve solution: the Cashco Pressure reducing regulator SLR-2 for pressure control, and the Ramén KSC Ball Sector Valves with actuator and positioner for precise flow regulation.

This exemplifies the potential of our flow control technology in supporting Rockwool to achieve:

• Increased efficiency: Oxyfuel combustion can optimize thermal output while minimizing nitrogen dilution, potentially reducing energy waste and emissions.
• Cleaner emissions: A more controlled process can lead to lower NOx emissions and facilitate easier CO₂ capture and storage.
• Sustainable production: The resulting stone wool products are designed to be durable, recyclable, and non-combustible, contributing to energy-efficient building solutions.