The Challenge
A large, integrated paper mill was struggling with maintaining temperature in its white water system. White water temperature is critical for fiber dispersion, chemical additive performance, and sheet formation, but in this area, process variability made heating especially difficult.
The mill had previously attempted to use several other brands of Direct Steam Injection (DSI) heaters, but they were unable to handle the variable operating conditions. Frequent swings in flow rate and steam pressure led to unstable operation, large swings in temperature, and poor reliability. Conventional spargers were ruled out due to scaling, steam hammer, and uneven mixing.
As an older mill, space constraints limited the available options for adding equipment.
To stabilize this process, the mill needed a solution that could:
- Deliver precise, reliable heating despite rapidly changing process conditions.
- Operate across a wide range of flow rates and steam pressures without requiring multiple heaters.
- Improve process stability and paper quality without significant capital investment.
- Have a small footprint and flexible installation requirements.
The Solution
ProSonix partnered with the mill to install an I-Series Direct Steam Injection Heater in the white water system. Unlike traditional injectors, the ProSonix heater’s internally modulated steam control ensured smooth, vibration-free operation and uniform mixing—eliminating hammer and fouling issues.
Key design conditions included:
- White water heated from 110°F to 160°F. (43-71°C)
- White water flow rates of 1,000 to 2,300 GPM. (227-522 M3/h)
- Steam pressure range 78–90 PSIG (538-620 Kpag)
- Achieving ±2°F temperature accuracy throughout operating range.
ProSonix I-Series heaters are compact and able to be installed in a variety of orientations, making it easy to find a suitable location.
Results & Benefits
- Achieved Temperature Goals: Raised white water to desired temperatures across highly variable flows and steam pressures using a single heater.
- Equipment Protection: Eliminated steam hammer, scaling, and vibration issues common with spargers and other DSI technologies.
- Improved Process Stability: Precise temperature control reduced variability, enhancing fiber performance, chemical efficiency, and overall paper consistency.
- Operational Reliability: One targeted installation delivered consistent results with minimal maintenance requirements.
Summary
This large pulp and paper mill overcame years of heating challenges in its white water system by installing a ProSonix I-Series Direct Steam Injection Heater. The ProSonix heater was able to handle wide swings in flowrate and steam pressure and deliver reliable heating, improved process stability, reduced variability, and enhanced paper quality without costly system overhauls.