What is the paper pulp preservative? A comprehensive explanation of its principles, selection, and application.2
IV. Key Indicators for Selection and Applicable Scenarios
4.1 Core Selection Criteria
Bactericidal spectrum: Priority broad-spectrum type (bacteria + molds + algae), covering a comprehensive range.
pH adaptability: Matches the pH of the slurry system (neutral / alkaline system selects isothiazolinone, acidic system can choose DBNPA).
Thermal stability: Adapted to production temperature (stable at ≤50℃, high-temperature system selects heat-resistant models).
Fiber safety: Non-degradable fibers, does not affect whiteness / strength, avoids fluctuations in paper quality.
Environmental compliance: Compliant with GB 4806, REACH, and FDA standards, low toxicity, easily degradable, no residual risk.
Cost efficiency: Low addition amount (0.01%–0.05%), high cost-effectiveness, balancing effectiveness and cost.
4.2 Suggestions for Selecting Scenarios
Chemical pulp / Mechanical pulp (original color pulp): The preferred choice is isothiazolinone (BIT/CMIT), which is broad-spectrum and safe, protecting the whiteness of the original color pulp.
Waste paper deinking pulp (high pollution): The preferred choice is DBNPA, which quickly kills bacteria and prevents contaminated pulp and ink odors.
Neutral / Alkaline papermaking system: Isothiazolinone combination, pH 6–10 stable, suitable for modern papermaking processes.
White water recycling system: DBNPA + isothiazolinone combination, rapid sterilization + long-lasting antibacterial, controlling sludge.
Export / High-end paper types: Isothiazolinone (fully certified), compliant with environmental protection, no residual risk.
V. Scientific Application Plan and Additive Process
5.1 Add Position (Precise Dosage)
Slurry mixing tank / Slurry formation tank: Main dosing point, directly in contact with the slurry to inhibit microbial proliferation.
Underground white water tank: Controls microorganisms in the white water to prevent cyclic pollution.
Starch glue / Auxiliary material tank: Prevents mold growth of auxiliary materials and avoids secondary pollution.
High-risk nodes for rotten slurry: Pipe elbows, slurry storage tower, key for intensive dosing.
5.2 Add Method (Choose as Needed)
Continuous addition: Low dose (0.01% - 0.02%) is continuously added, maintaining stable antibacterial effect, suitable for routine production.
Intermittent shock: High dose (0.03% - 0.05%) is added periodically (e.g. once a day), quickly killing stubborn microorganisms, suitable for periods with high incidence of rotten pulp.
Combined addition: DBNPA (shock) + Thiourea Oxide (maintenance), balancing rapid and long-lasting effects, achieving the best overall result.
5.3 Important Notes
Avoid mixing: Oxidizing and non-oxidizing disinfectants must not be mixed to prevent failure or dangerous reactions.
pH control: Isothiazolinones are stable at pH 3–11, while DBNPA is optimal at pH 4–9.
Safety precautions: Wear gloves and goggles during operation to avoid skin/mucous membrane contact.
Storage conditions: Store in a cool, dry place, avoiding high temperatures and direct sunlight. The shelf life is 12 months.
Core Conclusion
The anti-corrosion agent for paper pulp is a key additive that addresses microbial contamination and ensures stable production. Thiourea derivatives, due to their broad-spectrum, safe and stable properties, have become the mainstream choice; DBNPA is suitable for high-pollution scenarios due to its rapid bactericidal effect; oxidative disinfectants are used only as auxiliary disinfection. Scientific selection (matching pH / pulp seed), precise dosing (location / method / dosage) can achieve comprehensive benefits such as efficient anti-corrosion, low consumption and environmental protection, and quality improvement.
