Energy-Efficient Coating Preparation Systems for Board Production
Coating Preparation: The Foundation of Board Surface Quality
Coating board production requires precise coating formulation and application to achieve the surface properties demanded by packaging converters — smoothness, brightness, ink receptivity, and glueability. The coating preparation system is responsible for dispersing pigments, mixing binders, and delivering a homogeneous coating color at the correct solids content and viscosity to the coating stations.
A typical coating kitchen for a 200–400 TPD coating board machine handles 15–30 tonnes of dry coating per day, with coating color solids of 58–65% and Brookfield viscosity of 800–1500 mPa·s at 100 rpm. The system integrates pigment dispersion, binder dissolution, blending, screening, and supply tanks with continuous agitation.
Key Equipment Components
Pigment Dispersers
- High-speed dispersers: 55–132 kW motors, blade tip speed 18–25 m/s. Process 2–5 tonnes of pigment slurry per batch. Typical dispersion time: 20–40 minutes to achieve Hegman grind of 6–7.
- Bead mills (for fine grinding): 75–160 kW, media size 0.8–1.5 mm. Throughput: 500–2000 L/h. Used for calcium carbonate and clay slurries requiring particle size reduction below 2 μm.
Coating Color Preparation
- High-shear mixers: 30–75 kW, capable of handling viscosities up to 5000 mPa·s. Ensure uniform distribution of latex, starch, and co-binders throughout the pigment slurry.
- Pressure screens for coating: 100–150 μm slot width baskets remove agglomerates and contaminants. Throughput: 20–50 m³/h per unit at 60–65% solids.
Energy and Cost Optimization
Coating preparation typically accounts for 12–18% of total board machine energy consumption. Optimization strategies include:
- High-solids coating: Increasing solids from 60% to 64% reduces drying energy by 8–10% (approximately 0.05–0.08 t steam per tonne of coating).
- Variable frequency drives: Installing VFDs on disperser and mixer motors reduces energy consumption by 15–25% during partial load operation.
- Heat recovery from drying: Capturing exhaust heat for coating color pre-heating reduces steam consumption by 3–5%.
Maintenance Schedule
- Disperser blades: Inspect weekly for wear. Replace when blade diameter is reduced by >10%. Average service life: 3–6 months.
- Bead mill media: Top up media every 500 operating hours. Complete media change every 2000–3000 hours.
- Coating screens: Clean baskets daily to prevent coating buildup. Replace baskets every 6–9 months.
Contact Leizhan for Coating Board Production Solutions
Zhengzhou Leizhan Technology provides complete coating kitchen equipment and multi-layer forming systems for coating board production. For technical consultation on coating preparation systems, contact the engineering team.
📧 Email: leizhanzhang@gmail.com
🌐 Website: www.pulprefining.com