Section
| HS Code | 184063 |
| Product Name | MY-205 5% Active Water Treatment & Aquaculture Silicone Antifoam |
| Active Silicone Content | 5% |
| Appearance | Milky white liquid |
| Viscosity At 25 C | 150-300 mPa·s |
| Ph 1 Solution | 6.0-8.0 |
| Specific Gravity At 20 C | 1.00-1.05 |
| Solubility In Water | Dispersible |
| Emulsion Ionic Type | Non-ionic |
| Droplet Size | Fine particle dispersion |
| Defoaming Performance | Rapid foam knockdown |
| Antifoam Persistence | Long-lasting foam suppression |
| Recommended Dosage | 10-500 ppm |
| Shelf Life | 12 months |
| Storage Temperature | 5-35°C |
| Freezing Point | Below 0°C |
| Flash Point | Non-flammable |
As an accredited MY-205 5% Active Water Treatment & Aquaculture Silicone Antifoam factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Supplied in 25 kg HDPE pails with secure lids for safe handling, easy dosing, and stable storage in water treatment and aquaculture applications. |
| Container Loading (20′ FCL) | 20′ FCL loaded with MY-205 silicone antifoam: drums/pails palletized, secured, labeled, ventilated, avoiding heat, moisture, and incompatible substances. |
| Shipping | MY-205 is a 5% active silicone antifoam emulsion for water treatment and aquaculture. Ship as non-hazardous, non-regulated liquid in sealed drums, totes, or bulk containers. Protect from freezing, extreme heat, and prolonged sunlight. Ensure containers are upright, securely strapped, and kept dry during transit. |
| Storage | Store tightly sealed in original container in a cool, dry, well-ventilated area. Protect from direct sunlight, extreme heat, and freezing temperatures. Keep away from oxidizers and incompatible chemicals. Ensure the container remains uncontaminated when dispensing. Use within recommended shelf life. |
| Shelf Life | Store in original unopened container; shelf life is 24 months from manufacture date. Avoid freezing and extreme heat. |
For municipal wastewater aeration basins treating mixed domestic-industrial influent, MY-205 5% Active Water Treatment & Aquaculture Silicone Antifoam is metered into the activated sludge mixed liquor at the point of maximum turbulence before the clarifier splitter box. Jar tests using freshly drawn mixed liquor, not clean water, establish the initial as-supplied dose because filamentous extracellular polymeric substances alter coalescence efficiency. A starting range of 2–10 mg/L as supplied, equivalent to 0.1–0.5 mg/L active polydimethylsiloxane, is injected through a peristaltic pump. The dose is advanced in 2 mg/L increments every 30 min until surface foam coverage falls below 5% of basin area. Foam persistence is recorded by a modified ASTM D3601 bottle test using the same mixed liquor sample. The emulsion is diluted 1:5 to 1:10 with non-potable process water before injection to prevent localized oiling. In this application, the terminal output is clarified secondary effluent continuing to disinfection. No direct food-contact function is implied. Sludge settleability is monitored by sludge volume index when first applying the product because interfacial films can persist in high mixed liquor suspended solids conditions. Where discharge is governed by a National Pollutant Discharge Elimination System permit, the facility reports residual silicone contribution to total organic carbon in the monitoring plan. Published data for MY-205-specific effects on oxygen transfer efficiency in activated sludge basins is limited. Site-specific off-gas testing is advised when the dose exceeds 10 mg/L as supplied.
Where cooling tower foam arises from surfactant loading, glycol leaks, or biological organic films, MY-205 is injected into the cooling water return line upstream of the chemical feed manifold. A pre-dilution of 1:10 with filtered service water is applied before injection to stabilize the emulsion in high-hardness recirculating water. An initial slug dose of 5–20 mg/L as supplied is followed by periodic trim dosing of 1–5 mg/L when basin foam height remains above 10 cm for 15 min or more. The effective dose is not fixed. It shifts with cycles of concentration. At 4–6 cycles, the same active silicone concentration may persist longer because emulsion droplets are retained and continuous make-up water is low. Oxidizing biocides such as sodium hypochlorite must be injected at a separate point from the antifoam. Simultaneous high chlorine demand can degrade the polydimethylsiloxane emulsion and shorten antifoam persistence. Field monitoring includes visual foam collapse, basin surface coverage, and total dissolved solids. ASTM D3601 is used only as a relative screen because clean-water foam tests do not reproduce tower water surfactant matrices. Overdose in this system appears as a persistent surface sheen, heat exchanger film, or atypical condenser back-pressure changes. The corrective action is an immediate blowdown increase and dose suspension. The terminal output is recirculating cooling water with stable heat-transfer performance. Foam control must not mask microbiological fouling or scale indicators. Blowdown discharged to surface water remains subject to site NPDES permit limits. Silicone contribution to total organic carbon is included in the discharge monitoring report. Published data for MY-205-specific degradation in hypochlorite-treated cooling water is limited.
When membrane pretreatment feed contains coagulant polymers or dissolved air flotation carryover, foam can shorten cartridge filter run times and spill from open channels. MY-205 is added after coagulant flash mixing and before cartridge filtration at 0.5–5 mg/L as supplied, equivalent to 0.025–0.25 mg/L active silicone. This dose is deliberately low because the emulsion droplets may accumulate on polyethersulfone or polyamide membrane surfaces if the feed stream is overdosed. For potable service, the product must be authorized under NSF/ANSI/CAN 60, and the authorization document defines the maximum permitted dose. The site runs a modified fouling index comparison according to ASTM D8002 using the same feed water with and without antifoam. An increase exceeding 15% is treated as an unacceptable fouling risk. Continuous injection is preferred over slug dosing to minimize concentration excursions. The terminal output is desalinated process water or potable permeate. The regulatory limit is imposed by the drinking water authority rather than by foam performance. In high-salinity brine and concentrate lines, silicone emulsion stability may break prematurely. Site-specific salt tolerance can be tested by adding the product to a sample of plant brine and observing phase separation after 24 h. Published data for MY-205-specific stability in seawater or Arabian Gulf brine matrices is limited.
Recirculating aquaculture systems present a process conflict: foam fractionation or protein skimming relies on stable foam to remove dissolved organic carbon and fine solids, while silicone antifoam collapses that same foam. MY-205 is therefore not dosed upstream of foam fractionators or in the biofilter feed stream. The operational location is limited to degassing header boxes, pump sumps, and temporary transport tanks where nuisance foam creates overflow or equipment damage. A dose of 1–10 mg/L as supplied is introduced only after the foam fractionator outlet and before the degassing tower. This sequencing allows residual antifoam to break or dilute before the water returns to the culture tank. The terminal output is fish or shrimp biomass grown in recirculated water. No direct food-contact or therapeutic claim applies. Nitrification performance must be measured by ammonia oxidation rate per unit of moving-bed biofilm reactor surface area because chronic exposure of silicone emulsion droplets to biofilter media at doses above 10 mg/L as supplied may inhibit nitrite oxidation. The product is diluted 1:20 to 1:50 with system water and metered through a low-shear pump. High-shear in-line mixers can split the emulsion and form visible surface oil. Oxygen transfer to culture tanks may decline if surface foam removal is excessive. Dissolved carbon dioxide and pH are monitored because foam fractionators also strip carbon dioxide. Before use in food-producing aquatic animals, acute toxicity testing according to OECD 203 and early-life-stage exposure testing are required if supplier toxicity data for MY-205 is absent. Published data for MY-205-specific biofilter compatibility in RAS is limited.
For intensive shrimp and fish ponds with paddlewheel aerators, foam can form from dissolved proteins, saponins, and algal exopolysaccharides. MY-205 is applied at 0.5–2 mg/L as supplied pond volume, diluted 1:50 with pond water, and distributed along the aeration raceway rather than across the entire pond. The dilution and placement prevent a continuous surface slick. Application at the paddlewheel zone uses mechanical energy to disperse droplets into the air-water interface where the foam is generated. Foam collapse is evaluated visually against a site-defined grid. No ISO or ASTM foam test is directly applicable to whole-pond systems. Surface reaeration must be monitored with a dissolved oxygen probe calibrated per ASTM D888-18. A persistent silicone film at the air-water interface may reduce the oxygen transfer coefficient in static pond zones. This is the critical threshold: if surface film coverage exceeds 20% of pond area or dawn dissolved oxygen falls below 4.0 mg/L, dosing is suspended and aeration intensity is increased. The terminal output is harvest-sized aquatic animals produced in a pond environment. The defoamer is not a therapeutic agent and does not remove the organic loading or algal bloom that causes foam. Application is limited to short-duration foam events. Repeated dosing without water exchange may increase organic loading and suspended solids. Where the harvested animals are processed under US FDA jurisdiction, the status of the emulsion under 21 CFR 173.340 as a defoaming agent must be verified separately from the pond-use authorization. Published acute toxicity data for MY-205 in pond species is limited.
Dissolved air flotation units treating food-processing effluent generate a compact float sludge layer, but uncontrolled foam above the float obscures sight gauges, blocks overflow weirs, and destabilizes skimmer operation. MY-205 is dosed into the DAF feed line after pH adjustment and flocculant addition at 1–4 mg/L as supplied. Addition must occur downstream of flocculation to avoid breaking the polymer flocs that carry solids to the surface. Overdose reduces bubble-particle attachment efficiency and increases effluent turbidity. This limitation requires jar testing of each new waste stream using a DAF bench unit or standard jar apparatus. Turbidity is measured by ISO 7027, and total suspended solids by APHA 2540 D. The clarified water must remain below the discharge permit threshold. The terminal output is clarified effluent discharged to sewer or secondary treatment. Foam suppression is only acceptable when the float sludge layer remains continuous and settled solids in the clarified water do not exceed the facility's permit limit. For waste streams containing synthetic surfactants, the emulsion may partition into the float sludge rather than the clarified water. Solids analysis is required prior to beneficial reuse. If the treatment site is within the European Union, the exact substance identity and use descriptor must be registered under REACH Regulation (EC) No 1907/2006 for the site's waste treatment process. Published data for MY-205-specific partitioning in food-processing DAF sludge is limited.
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Introduced as a water-dispersible silicone emulsion, the MY-205 5% Active Water Treatment & Aquaculture Silicone Antifoam presents a 5% w/w active silicone fraction of polydimethylsiloxane and hydrophobic silica dispersed in a nonionic surfactant-stabilized aqueous matrix. The model designation MY-205 identifies the lot-controlled emulsion rather than a mineral-oil or solvent-thinned formulation. In water treatment service, the material is used in turbulent feed channels, aeration basins, dissolved air flotation cells and clarifier launders to suppress foam without introducing hydrocarbon sheen. In aquaculture, the product is directed at foam generated by protein skimmers, raceway aeration and biofilter off-gas; suitability for direct pond immersion must be confirmed against local residue regulations and farm-specific oxygenation protocols.
Batch-release control points for the MY-205 class are summarized in Table 1. The values describe a typical 5% active silicone emulsion; batch-specific certificates of analysis should be consulted for actual flow properties. The emulsion is a milky white liquid with a density close to water, which reduces float separation in low-velocity dosing lines. Viscosity is controlled to allow feed through metering pumps without requiring solvent pre-dilution, though in-line dilution with non-potable process water can reduce local concentration spikes when injection points are located in low-energy zones.
| Parameter | Representative value | Test method / equipment |
|---|---|---|
| Active silicone solids | 5.0 ± 0.5% w/w | Internal solvent-extraction gravimetry |
| Appearance | Milky white liquid | Visual inspection against backlit panel |
| pH, 1% dilution in deionized water | 6.5–8.0 | ISO 4316, potentiometric |
| Viscosity at 25 °C | 500–2,000 mPa·s | ISO 2555, Brookfield LV, 60 rpm |
| Density at 20 °C | 0.99–1.02 g/cm³ | ISO 2811-1 |
| Storage temperature | 5–35 °C | Sealed original container |
Foam knockdown in aqueous systems occurs when the silicone active droplet contacts a foam lamella and spreads across the air-water interface because the low surface tension of polydimethylsiloxane creates a positive spreading coefficient against the surrounding water phase. The hydrophobic silica particles incorporated in the active fraction pierce the film and create a capillary pressure differential that drains liquid from the lamella. This dual mechanism differs from polyether antifoams, which reduce surface elasticity by replacing foam-stabilizing surfactants at the interface but do not necessarily introduce a solid particle bridging component. In water treatment mixed liquor, naturally occurring soluble proteins and extracellular polymeric substances oppose defoaming by increasing interfacial elasticity; therefore the effective dose is not fixed and must be titrated against organic loading.
Dosing location controls both immediate foam collapse and the severity of downstream slick formation. In dissolved air flotation units, the emulsion should be introduced into the feed line upstream of the air saturator or directly into the saturator suction if the pump is tolerant of low-volume water-like emulsions. Post-release addition at the flotation cell nozzle is not recommended because the sudden pressure drop creates a high-shear zone that separates the nonionic emulsifier from the silicone active fraction; the resulting coalesced droplets rise as visible grease-like loci on the clear water zone. In a conventional dissolved air flotation unit handling food processing effluent, the effective dose is reached when the foam height at the scum beach is reduced to a level compatible with skimmer travel and downstream sludge channel flow. Published data for the specific MY-205 configuration is limited, and optimal feed rate should be established by jar test with the actual effluent and air injection temperature.
In recirculating aquaculture systems, surface foam in raceways and pumping sumps is commonly generated by dissolved organics and proteinaceous surfactants from uneaten feed and fecal material. The MY-205 emulsion can be applied to the suction side of circulation pumps or into venturi oxygen injection loops at rates sufficient to collapse the foam film but not high enough to produce an enduring surface layer. Because silicone actives are non-biocidal and function by surface-spreading, the product does not oxidize the dissolved organic compounds that stabilize foam. Foam return after the active droplet population is diluted or removed by solids filtration requires a continuous or semicontinuous feed at a rate matched to organic loading. Operators should monitor dissolved oxygen after initial application, particularly in systems with fall-based or diffuser-based aeration, because excessive surface film can alter the gas transfer coefficient of the air-water interface.
In sludge thickening and belt press filtrate applications, the nonionic emulsifier package of MY-205 is generally less disruptive to cationic polyacrylamide flocculation than anionic or strongly ionic antifoam packages, but compatibility is not guaranteed. Jar tests should combine the antifoam with the polymer solution in the same order and at the same time delay expected on the production line. A common failure mode observed in thickening operations is the formation of small, low-density flocs when the antifoam is added after polymer activation; the residual silicone droplets concentrate at the floc surface and reduce hydrophilicity, impairing settling. The antifoam should therefore be injected upstream of the polymer dilution water or into the sludge feed before the polymer maturation point, and the dose should be minimized to 2–10 mg/L when filtrate is returned to the headworks. This range is an operational window, not a specification limit.
The differences between MY-205 and alternative foam-control agents are summarized in Table 2. The product’s 5% w/w active silicone level is intentionally lower than concentrated silicone compounds because water treatment and aquaculture systems often require lower active doses and easier pumpability. Mineral-oil antifoams contain hydrophobic silica and a hydrocarbon carrier; their initial knockdown is generally slower and the carrier may persist as a visible sheen in clarifiers and receiving waters. Polyalkylene glycol antifoams are water-soluble and less prone to sheen, but their foam persistence is frequently shorter under continuous aeration because the active polymer is carried out of the surface layer more readily.
| Characteristic | MY-205 silicone emulsion | Mineral oil/silica | Polyalkylene glycol |
|---|---|---|---|
| Active fraction | 5% w/w PDMS/silica | 100% carrier/active blend | Typically 100% active |
| Typical product dose in water treatment | 1–50 mg/L by jar test | 5–100 mg/L | 10–200 mg/L |
| Foam knockdown speed | Fast | Moderate | Moderate |
| Foam persistence | Long because of low water solubility | Moderate | Shorter under high dilution |
| Surface sheen potential | Low at controlled dose | High | Low |
| Oxygen transfer impact | Dose-dependent surface film | Surface film hazard | Lower film but possible COD burden |
In membrane bioreactors, direct addition to the membrane tank is not recommended because silicone emulsion droplets can adsorb onto hydrophobic PVDF or polyethersulfone membrane surfaces and contribute to fouling resistance. The product should be added upstream of fine screens and given residence time in the mixed liquor for the active droplets to attach to foam lamellae before the filtration step. In aquaculture water reuse loops, the product should not be viewed as a replacement for solids removal; its action is limited to foam-film destabilization and does not remove dissolved proteins or suspended solids. Where biofilter nitrification performance is critical, preservatives and emulsifier components must be evaluated for microbial inhibition through a side-stream nitrification inhibition test before full-volume addition.
Storage and handling are governed by the emulsion’s freeze sensitivity. Repeated freeze-thaw cycles reduce droplet size uniformity and may lead to phase separation in the container. If freezing occurs, the container should be warmed gradually to 20–25 °C and agitated by recirculation rather than strong air sparging; high shear can destabilize the emulsion and create coarse silicone slicks upon use. The product should not be mixed with strong acids or oxidizing biocides in concentrated form because low pH or oxidative conditions can split the emulsifier from the silicone phase. For continuous dosing, low-flow metering pumps with nitrile or EPDM liquid ends are suitable; silicone oil can swell natural rubber components over extended contact.
Quality-control documentation for MY-205 includes batch viscosity, pH, silicone content and visual emulsion stability. The material is not a defoamer for non-aqueous systems; addition to solvent-based or oil-based process streams may create insoluble deposits. In cooling water and boiler water applications where steam purity is critical, the product should be evaluated for carryover of silica and silicone volatile fractions using the actual steam generation equipment and condensate monitoring. For potable water treatment, end-use approval under NSF/ANSI 60 or equivalent national standards must be confirmed for the specific batch and dosing location. In aquaculture applications involving food-producing species, the safety data sheet and local residue limits should be reviewed before use, because the 5% active silicone level alone does not establish regulatory clearance. Published data for the specific MY-205 configuration in high-pressure steam systems is limited; therefore any use outside municipal aeration, dissolved air flotation, clarifier and aquaculture foam control should be preceded by side-stream evaluation.
