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Next Generation Refrigerants & Their Lubricants. Jeng-Shiang Tsaih Patech Fine Chemicals Co., Ltd. www.patechfc.com.tw. Major Refrigerants. C FC HCFC HFC HFO NH 3 &CO 2 R32 Hydrocarbons . www.patechfc.com.tw. Refrigerant Classification. P atech. www.patechfc.com.tw.
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Next Generation Refrigerants & Their Lubricants Jeng-ShiangTsaih Patech Fine Chemicals Co., Ltd. www.patechfc.com.tw
Major Refrigerants • CFC • HCFC • HFC • HFO • NH3 &CO2 • R32 • Hydrocarbons www.patechfc.com.tw
Refrigerant Classification Patech www.patechfc.com.tw
Basic Data of Refrigerants Patech www.patechfc.com.tw
Refrigerant Nomenclature Patech www.patechfc.com.tw
Chemical Structure Effect Patech www.patechfc.com.tw
Safety Classification (ASHRAE) Patech Safety Group(ASHRAE 34--2007) A lot of low GWP refrigerants meet A2L group www.patechfc.com.tw
Flammability Consideration Patech • Lower flammability limit (LFL) is the lower end of the concentration range of a flammable solvent at a given temperature and pressure for which air/vapor mixtures can ignite. The GWP and LFL data of some alternatives www.patechfc.com.tw
Refrigerant Progression Patech www.patechfc.com.tw
Environmental Consideration Patech • Environmental Drivers Affecting Industry • Ozone Depletion Effect • Montreal Protocol • ODP • Climate Change Effect • Kyoto Protocol • GWP www.patechfc.com.tw
Environmental Drivers Affecting Industry Patech • Ozone Depletion Effect • Protective Ozone Layer Damaged • By Chlorine & Bromine Gases. • Montreal Protocol In September 16,1987 • Bans CFCs • HCFC R22 Elimination • ODP must be zero • The ozone depletion potential (ODP) of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with R-11 being fixed at an ODP of 1.0. www.patechfc.com.tw
Ozone Depletion Effect HCFC Phase-out Patech www.patechfc.com.tw
Environmental Drivers Affecting Industry Patech • Climate Change Effect • “Greenhouse Gases” Contribute To Global Warming Is Theory. • Kyoto Protocol (1997) Aims To Curb All Greenhouse Gases. • Most Refrigerants In Use Today Are Classified As Greenhouse Gases. • Global-warming potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere. www.patechfc.com.tw
Climate Change EffectHFC Phase-out Patech www.patechfc.com.tw
Another Assessment for Global Warming Patech • GWP is important but not the only measure of environmental impact! • Refrigerants should be measured on TEWI or LCCP analysis • TEWI : Total equivalent warming impact • LCCP : Life-Cycle Climate Performance www.patechfc.com.tw
TEWI & LCCP Analysis Patech Life Cycle Performance • Typical Low Charge Systems: • AC, Heat Pump, Reach-In, Walk-In, Transport • Applications • For Hermetic Systems, Global Warming Is An Efficiency Issue. • Future Refrigerants Must Be Equal Or Higher Efficiency. • Typical Large Refrigeration Systems: • Global Warming Becomes An Efficiency Issue If Charge/Leaks Are Reduced. • Future Refrigerants Must Be Equal Or Higher Efficiency. www.patechfc.com.tw
HoneyWell HFO Refrigerants Patech www.patechfc.com.tw
HFO-1234yf Patech www.patechfc.com.tw
HFO-1234yf Patech . Excellent environmental properties – Very low GWP of 4, Zero ODP, Favorable LCCP – Atmospheric chemistry determined and published . Low toxicity, similar to R-134a – Low acute and chronic toxicity – Significant testing completed . System performance very similar to R-134a – Excellent COP and Capacity, no glide from both internal tests and OEM tests – Thermally stable and compatible with R-134a components – Potential for direct substitution of R-134a . Mild flammability (manageable) – Potential to use in a direct expansion A/C system - better performance, lower weight, smaller size than a secondary loop system www.patechfc.com.tw
HFO-1234yf or CO2 in MAC? Patech • EU: GWP of passenger car refrigerants < 150 (2011) • VDA (German Association of the Automotive Industry ) had • re-affirmed intention to adopt CO2, based on flammability • risks assessments in Europe. • H-D re-affirms validity of flammability risks assessments : • SAE CRP-1234 & U.S EPA. • CO2& HFO-1234yf both remain as options www.patechfc.com.tw
HFO-1234ze Patech www.patechfc.com.tw
HFO-1234ze for Chiller Patech Low GWP Replacements for Chillers • Equal (or better) efficiency compared to R-134a • 99.7% reduction in GWP www.patechfc.com.tw
Trade Off: GWP vs. Performance Patech www.patechfc.com.tw
R410a Replacement- L41 Blend Patech • L-41offers good performance and a significant GWP reduction from R-410A (>75%) • It enables compact high efficiency systems in many regions. • No problems with high discharge temperatures. • L-41 shows lower operating pressures than R-410A and R-32. www.patechfc.com.tw
Operating Pressure Consideration Patech www.patechfc.com.tw
R410a Replacement- L41 Blend Patech Haier A/C unit – Solstice L41 • Safer than HCs • Using R410A technology. • More than 75% reduction in GWP versus R410A. • 30% reduction in GWP versus R32. • Lower discharge pressure than R32. • Lower Discharge temperature than R32. • Lower power consumption than R410A and R32 at high ambient temperature regions. www.patechfc.com.tw
CO2 Refrigerant Patech • The main advantages are a very low environmental impact, non- • flammability and non-toxicity. • The disadvantage is high pressure at low temperatures. • Hot water Heat Pump applications: the application matches the • supercritical temperature glide in the CO2 gas cooler providing • good efficiencies inside a compact system. • Auto A/C applications www.patechfc.com.tw
R-32 Refrigerant Patech CH2F2Difluoromethane (R32) CAS Number : 75-10-5 • Molecular weight : 52.02 g/mol • Boiling point : -51.7 °C • Latent heat of vaporization (1.013 bar at boiling point) : 360.24 kJ/kg • Vapor pressure (at 20 °C or 68 °F) : 13.8 bar • Critical temperature : 78.4 °C • Critical pressure : 53.8 bar www.patechfc.com.tw
R-410 Replacement Patech • R-32 is one of the primary constituents of both R-410A and • R-407C. R-32 is an A2L refrigerant having a GWP (675) • approximately 70% less than that of R-410A, which makes it a • lower GWP alternative to R-410A. • R-32 exhibits slightly higher capacity and efficiency than R- • 410A. • R-32 has an A2L flammability rating, the flammability would • need to be mitigated in the design of the product by • compliance with an applicable safety standard such as IEC • 60335-2-40. R-410A systems should be able to be redesigned • for R-32 with minor modifications. www.patechfc.com.tw
R410a Replacement Patech As R-32 concentration becomes richer, R-32/HFO-1234yf mixtures develop the same characteristics as those of R-410A. www.patechfc.com.tw
R-22 Replacement Patech • R-32 is not a drop in for R-22 since its pressure is around 60% • higher and its capacity is also approximately 60% greater than • R-22 . R-22 systems would require significant redesign including: • lower displacement compressors and other changes to the • refrigeration system components to address the higher • operating pressures; which will be nearly the same changes • needed to redesign R-22 equipment to use R-410A. • The refrigeration capacity can increase 8. 5% of the R22 system • and the EER can increase by up to 7. 1%. www.patechfc.com.tw
R-290 Refrigerant R-290 --Propane (C3H8) • Hydrocarbon systems are commercially available in a number of • low charge air conditioning applications, such as small split, • window and portable air conditioners. • R-290 is the most frequently used hydrocarbon refrigerant in air • conditioning applications. When used to replace R-22, R-290 has • performance characteristics which yield slightly better • performance than R-22. • Compared to HFCs, hydrocarbon refrigerants have: reduced charge • levels (approximately 0.05 - 0.15 kg/kW of cooling capacity), • miscibility with mineral oils (synthetic lubricants are not required), • reduced compressor discharge temperatures, and improved heat • transfer due to favourable thermo-physical properties. www.patechfc.com.tw
R-290 Refrigerant Patech • The factor that works against the safe application of R-290 in air conditioning systems is its high flammability, which creates significant safety concerns in application, installation and field service. European and international standards limit the quantity of R-290 that can be used in a system. • The risk of ignition during normal operation is extremely low. The situation leading to highest risk is sudden leaks, refrigerant handling, and servicing activities. Thus, installation and service practices must be modified to avoid exposing consumers and service technicians to the additional risks associated with highly flammable refrigerants. www.patechfc.com.tw
R-290 Refrigerant Patech • Another factor that must be considered with flammable • refrigerants will be refrigerant reclaim and recovery • requirements. Current recovery and recycling practices depend • largely upon national or regional regulations. options. • Compare to MO/R-290 system, the miscibility of POE/R290 is • poor, so the phenomenon of viscosity dilution is less than • MO/R-290. This result in good lubrication. www.patechfc.com.tw
Vapor Pressures Consideration Patech www.patechfc.com.tw
Approach To Refrigerant Selection Patech Safety A1,A2,A2L,LFL Flammability Toxicity Environment (Montreal Protocol) Stratospheric Ozone GWP & (TEWI/LCCP) Performance COP, Discharge Temp…. Temp glide, Vapor pressure… Physical Properties Energy Capacity (Annual/Peak) Economics Drop-in consideration Total Cost Technology Changes Integrated Analysis Leading To The Selection Of The Best Refrigerant www.patechfc.com.tw
Respective Properties Comparison Patech www.patechfc.com.tw
Benefits and Drawbacks Patech www.patechfc.com.tw
Definition Patech Coefficient of performance (COP) This is used to define heat pump efficiency. COP = Q/ W Where: COP = Coefficient of performance (Unit-less) Q = Energy output (kWh or kJ). W = Electrical or mechanical energy input (kWh or kJ). Energy Efficiency Ratio (EER) www.patechfc.com.tw
Energy Efficient Refrigerants Patech • No refrigerant represents the ideal solution in all cases and for • every equipment – each cooling application has to be looked at • in its own merits and a professional choice must be made taking • into account many more factors than simply GWP. • Energy efficiency is the most relevant criterion to assess the • suitability of a refrigerant in R&AC systems. • On small systems: HCs tend to be more energy efficient. • On large systems: CO2 or NH3are more energy efficient. • On Air-condition systems: HCs> HFO-1234yf> CO2 • On Refrigeration systems: HCs> HFO-1234yf ≒ CO2 • On Heating Pumps: CO2 >HCs> HFO-1234yf www.patechfc.com.tw
Approval to Use Patech • Most would be restricted in Japan, U.S., EU. Not just technical • barriers but also legislative and regulatory barriers. • CO2 : No major regulatory barriers in any region. • Ammonia : Likely to remain restricted to industrial applications • due to toxicity. • Hydrocarbons : Likely to be limited to small refrigeration or room • AC applications due to flammability concerns, unless additional • research can alleviate these concerns. • A2L Fluids : Gaining increased acceptance, but will require: • – Risk assessments to address safety. • – Changes to building codes. • – Changes to equipment safety standards. www.patechfc.com.tw
Patech Oil in Refrigeration System www.patechfc.com.tw
Refrigeration Oil Requirements Patech www.patechfc.com.tw
The Structure of Refrigeration Oils Patech • Mineral Oil (MO): Refined petroleum product, straight or branched chain hydrocarbons. Non-polar chemistry means they mix well with CFCs, OK with HCFCs, not with HFCs. MO • Alkyl Benzene (AB): Synthetic lubricant made to act like • mineral oil, long chain hydrocarbons with closed rings. Somewhat polar - better HCFC miscibility. AB www.patechfc.com.tw
The Structure of Refrigeration Oils Patech • Polyalkylene Glycol (PAG): • Long chain hydrocarbons with alcohol functions. Manufactured chemical that is slippery like oil, but has chemical functions that make it polar - so it will mix with HFCs. Because of its relatively low electric resistivity, however, PAG could not be used in the hermetic compressors used in domestic refrigerators. PAG PVE • Polyvinylether (PVE): The chemical chain of PVE oil shows • similar characteristics to mineral oil (Hydrocarbon) with both good lubricity and similar dialectic strength. In addition, the chemical structure’s side chain has characteristics of PAG oil, with good • solubility and no hydrolysis. www.patechfc.com.tw
The Structure of Refrigeration Oils Patech POE • Polyol Esters (POE): • Synthetic lubricants with ester functions in the middle of long chain hydrocarbons. More polar so they mix better with HFCs. POE lubricants are desirable because of their environmental benefits. They can be synthesized from renewable resource and are biodegradable. They are used mainly in domestic and commercial refrigerant systems. They are miscible with mineral oils, hence can be used for retrofits. www.patechfc.com.tw
Advantages of POE Lubricant Patech Advantage of POE Lubricants www.patechfc.com.tw
Refrigeration Oil Comparison Patech www.patechfc.com.tw
Experimental Parameters Patech • There are a number of interactions between the refrigerant and the lubricant that need to be investigated in order to produce systems that are optimized for use. • Miscibility • Solubility (P-V-T) • Thermal Stability • Lubricity • Life Cycle Test www.patechfc.com.tw
Miscibility & Solubility Patech • Miscibility • The ability of two liquids to • mix and form a single phase • Miscibility Curves • Solubility • The ability of a gas to dissolve into a liquid • P-V-T Charts Pressure-Viscosity-Temperature-composition relationship www.patechfc.com.tw