In alkaline pulping, pulp washing, and papermaking sizing, fatty acids and resin acids in raw materials react with added sodium hydroxide and sodium sulfide to form foaming substances like saponified compounds, residual alkali, and alkali lignin. Combined with foam stabilization by cellulose and air entrainment during pulp conveying and mixing,大量stable foam is generated. These foams reduce equipment utilization, slow production, and impair washing and sizing quality — a long-standing industry challenge. Traditional mineral oil or ordinary silicone defoamers easily break emulsion and fail in high-alkali high-temperature environments, unable to meet the persistent defoaming demands of long alkaline processes (especially black liquor washing). With diversified raw materials like bamboo and bagasse pulp, and green production demands for "rapid defoaming, low dosage, no post-pollution", finding a "high-alkali-resistant, heat-resistant, easily dispersible, nonionic" specialized defoamer has become a key pulping issue.
Addressing this,
Anhui IOTA Silicone Oil Co., Ltd. officially launches
Defoamer for Papermaking Pulping IOTA 1831. Characterized by "appearance: white micro-emulsion; emulsion ionic type: nonionic; pH 7±1; active content ≥10%; centrifugal stability (3000rpm, 15min): no layering, no precipitation; viscosity 500–1500cSt; heat resistance ≤100℃; diluent: water", with modified polysiloxane as main material, combined with well-dispersing aids, special alkali-resistant emulsifiers, and siloxane addition products, backed by "outstanding alkali resistance + rapid defoaming + nonionic safety + no post-pollution", it serves as the "clean choice" for alkaline pulping defoaming,
achieving the leap from "uncontrollable foam in high alkali" to "alkali-resistant defoaming, pulp new clean".
System Positioning: Modified Polysiloxane Defoamer vs. Ordinary Silicone/Mineral Oil Defoamers
IOTA 1831 belongs to the modified polysiloxane emulsion defoamer family, distinct from traditional polydimethylsiloxane (PDMS) and mineral oil defoamers. Ordinary PDMS easily emulsifies and creaming in high-concentration alkali (pH>10); mineral oil defoamers have poor persistence and may cause post-pollution (paper defects, equipment coking). IOTA 1831 modifies the polysiloxane backbone via siloxane addition products, with special alkali-resistant emulsifiers, keeping the emulsion stably dispersed in strong alkaline pulping systems under nonionic state — exerting PDMS low-surface-tension rapid spreading while avoiding alkali-induced emulsion breaking.
Molecular Architecture: Modified Polysiloxane + Special Alkali-Resistant Emulsifier + Siloxane Addition Product
The core design of IOTA 1831 comes from its ternary composite structure:
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Modified Polysiloxane Main Body: Chemically modified backbone reduces surface tension far below water/foam film, enabling defoamer droplets to rapidly spread on foam liquid film surface, causing local thinning and rupture.
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Special Alkali-Resistant Emulsifier: Evenly disperses active ingredients into white micro-emulsion (500–1500cSt) under nonionic condition, ensuring no layering or precipitation in alkaline black liquor at pH 13–14, with excellent centrifugal stability.
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Siloxane Addition Product: As synergistic defoaming component, enhances penetration and suppression against stubborn foam stabilizers like lignin and resin acid saponates, extending foam inhibition time.
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Clear Physicochemical Baseline: pH 7±1 near neutral for good compatibility; heat resistance ≤100℃ matches pulping/washing temperature window; active content ≥10% ensures effective concentration.
Performance Leap: From "Foam Accumulation Delaying Production" to "Rapid Defoaming New Clean"
Introducing IOTA 1831 brings the following improvements across pulping:
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Outstanding Alkali Resistance: Designed for alkaline pulping, stable in high-alkali black liquor, no creaming, no failure.
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Rapid Defoaming: Quickly eliminates foam caused by lignin and other surfactants, fast action, low dosage.
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No Post-Pollution: No harmful residues, avoiding paper defects and equipment fouling, meeting green production requirements.
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Heat Adaptation: ≤100℃ heat resistance covers washing, bleaching, screening temperatures.
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Flexible Dilution: Can be diluted with water, simply mixed, convenient for on-site drip control.
Application Penetration: From Alkaline Main Line to Black Liquor Washing
IOTA 1831 covers full-scene defoaming in pulping and papermaking:
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Alkaline Pulping: Washing, bleaching, screening after NaOH/Na2S cooking.
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Special Pulps: Bamboo pulp, bagasse pulp, neutral pulping.
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Black Liquor Treatment: Dedicated foam control for black liquor washing lines.
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Papermaking Sizing: Foam control in internal and surface sizing.
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Water Treatment: Foam suppression in pulping wastewater treatment.
IOTA Technical Guide: Drip Control, Use Diluted Immediately
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Application: Direct drip with dosing pump into foaming system. Recommended initial dosage 0.08–0.5kg defoamer per ton pulp, expected 0.05–0.3kg per ton (air-dried). Optimize drip point for minimum effective dosage.
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Dilution: Dilute with water and mix slowly. Diluted defoamer should be used ASAP, generally stored no more than 12 hours.
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⚠️ Taboo: Avoid sunlight (store cool dry); diluted product not for long storage (≤12h); prevent freezing or overheating (heat resistance ≤100℃); separate from strong oxidants; avoid direct skin contact.
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Storage: 50kg plastic drum, 200kg iron drum, or per customer request. Store in cool dry place, avoid sunlight. Shelf life ≤1 year, transport as general goods. Along with IOTA 1823 (oil-based defoamer, 25kg plastic drum, general goods), IOTA 1831 is specifically designed for aqueous alkaline pulping with larger packaging (50/200kg) for industrial lines.
Industry Insight: The core value of pulping defoamer lies in "modified polysiloxane for low-surface-tension rapid breaking, special alkali-resistant emulsifier for high-alkali stable dispersion, siloxane addition product for lignin stubborn foam penetration". IOTA 1831, with "white micro-emulsion, nonionic, pH 7±1, active ≥10%, viscosity 500–1500cSt, heat ≤100℃, centrifugal stable, 50/200kg drum, ≤1yr" hard parameters,
fills the rapid defoaming link of domestic alkali-resistant defoamers in alkaline pulping, black liquor washing, and bamboo/bagasse lines. For paper mills, it upgrades along the path of "mineral oil defoamer → ordinary silicone defoamer → modified polysiloxane alkali-resistant defoamer", reducing defoamer consumption, increasing machine speed and equipment utilization, achieving pulp new clean and green premium.
