7 Safety Classification (ASHRAE) PatechSafety Group(ASHRAE )A lot of low GWP refrigerants meet A2L group
8 Flammability Consideration PatechLower 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
11 Environmental Drivers Affecting Industry PatechOzone Depletion EffectProtective Ozone Layer DamagedBy Chlorine & Bromine Gases.Montreal Protocol In September 16,1987Bans CFCsHCFC R22 EliminationODP must be zeroThe 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.
13 Environmental Drivers Affecting Industry PatechClimate 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.
15 Another Assessment for Global Warming PatechGWP is important but not the only measure of environmental impact!Refrigerants should be measured on TEWI or LCCP analysisTEWI : Total equivalent warming impactLCCP : Life-Cycle Climate Performance
16 Life Cycle Performance TEWI & LCCP AnalysisPatechLife Cycle PerformanceTypical Low Charge Systems:AC, Heat Pump, Reach-In, Walk-In, TransportApplicationsFor 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.
19 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 OEMtests– 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
20 HFO-1234yf or CO2 in MAC? Patech EU: GWP of passenger car refrigerants < 150 (2011)VDA (German Association of the Automotive Industry ) hadre-affirmed intention to adopt CO2, based on flammabilityrisks 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
24 R410a Replacement- L41 Blend PatechComposition wt%R32HFO-1234yfHFO-1234zeL41-Blend73%15%12%L-41 offers 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.
26 R410a Replacement- L41 Blend PatechHaier A/C unit – Solstice L41Safer than HCsUsing 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.
27 CO2 RefrigerantPatechThe 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 thesupercritical temperature glide in the CO2 gas cooler providinggood efficiencies inside a compact system.Auto A/C applications
28 CH2F2 Difluoromethane (R32) CAS Number : 75-10-5 R-32 RefrigerantPatechCH2F2 Difluoromethane (R32) CAS Number :Molecular weight : g/molBoiling point : °CLatent heat of vaporization (1.013 bar at boiling point) : kJ/kgVapor pressure (at 20 °C or 68 °F) : 13.8 barCritical temperature : 78.4 °CCritical pressure : 53.8 bar
29 R-410 ReplacementPatechR-32 is one of the primary constituents of both R-410A andR-407C. R-32 is an A2L refrigerant having a GWP (675)approximately 70% less than that of R-410A, which makes it alower 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 wouldneed to be mitigated in the design of the product bycompliance with an applicable safety standard such as IECR-410A systems should be able to be redesignedfor R-32 with minor modifications.
30 R410a ReplacementPatechAs R-32 concentration becomes richer, R-32/HFO-1234yf mixtures develop the same characteristics as those of R-410A.
31 R-22 ReplacementPatechR-32 is not a drop in for R-22 since its pressure is around 60%higher and its capacity is also approximately 60% greater thanR-22 . R-22 systems would require significant redesign including:lower displacement compressors and other changes to therefrigeration system components to address the higheroperating pressures; which will be nearly the same changesneeded to redesign R-22 equipment to use R-410A.The refrigeration capacity can increase 8. 5% of the R22 systemand the EER can increase by up to 7. 1%.
32 R-290 Refrigerant R-290 --Propane (C3H8) Hydrocarbon systems are commercially available in a number oflow charge air conditioning applications, such as small split,window and portable air conditioners.R-290 is the most frequently used hydrocarbon refrigerant in airconditioning applications. When used to replace R-22, R-290 hasperformance characteristics which yield slightly betterperformance than R-22.Compared to HFCs, hydrocarbon refrigerants have: reduced chargelevels (approximately kg/kW of cooling capacity),miscibility with mineral oils (synthetic lubricants are not required),reduced compressor discharge temperatures, and improved heattransfer due to favourable thermo-physical properties.
33 R-290 RefrigerantPatechThe 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.
34 R-290 RefrigerantPatechAnother factor that must be considered with flammablerefrigerants will be refrigerant reclaim and recoveryrequirements. Current recovery and recycling practices dependlargely upon national or regional regulations. options.Compare to MO/R-290 system, the miscibility of POE/R290 ispoor, so the phenomenon of viscosity dilution is less thanMO/R-290. This result in good lubrication.
36 Approach To Refrigerant Selection PatechSafetyA1,A2,A2L,LFLToxicityFlammabilityEnvironment(Montreal Protocol)Stratospheric OzoneGWP&(TEWI/LCCP)PerformanceTemp glide, Vapor pressure…COP, Discharge Temp….Physical PropertiesEnergy Capacity(Annual/Peak)EconomicsDrop-in considerationTechnology ChangesTotal CostIntegrated AnalysisLeading To The Selection Of The Best Refrigerant
39 Definition Patech Coefficient of performance (COP) This is used to define heat pump efficiency.COP = Q / WWhere: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)
40 Energy Efficient Refrigerants PatechNo refrigerant represents the ideal solution in all cases and forevery equipment – each cooling application has to be looked atin its own merits and a professional choice must be made takinginto account many more factors than simply GWP.Energy efficiency is the most relevant criterion to assess thesuitability of a refrigerant in R&AC systems.On small systems: HCs tend to be more energy efficient.On large systems: CO2 or NH3 are more energy efficient.On Air-condition systems: HCs＞ HFO-1234yf＞ CO2On Refrigeration systems: HCs＞ HFO-1234yf ≒ CO2On Heating Pumps: CO2 ＞HCs＞ HFO-1234yf
41 Approval to UsePatechMost would be restricted in Japan, U.S., EU. Not just technicalbarriers but also legislative and regulatory barriers.CO2 : No major regulatory barriers in any region.Ammonia : Likely to remain restricted to industrial applicationsdue to toxicity.Hydrocarbons : Likely to be limited to small refrigeration or roomAC applications due to flammability concerns, unless additionalresearch 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.
44 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.MOAlkyl Benzene (AB):Synthetic lubricant made to act likemineral oil, long chain hydrocarbons with closed rings. Somewhat polar - better HCFC miscibility.AB
45 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.PAGPVEPolyvinylether (PVE):The chemical chain of PVE oil showssimilar 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 goodsolubility and no hydrolysis.
46 The Structure of Refrigeration Oils Patech POEPolyol 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.
47 Advantage of POE Lubricants Advantages of POE LubricantAdvantage of POE LubricantsPatech
49 Experimental Parameters PatechThere 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.MiscibilitySolubility (P-V-T)Thermal StabilityLubricityLife Cycle Test
50 Miscibility & Solubility PatechMiscibilityThe ability of two liquids tomix and form a single phaseMiscibility CurvesSolubilityThe ability of a gas to dissolve into a liquidP-V-T Charts Pressure-Viscosity-Temperature-composition relationship
51 Different Refrigerants, Different Miscible Phenomena Miscibility CurvesPatechDifferent Refrigerants, Different Miscible Phenomena
53 Compatibility & Energy Efficiency PatechThe more miscible one makes the lubricant with the refrigerant, the more soluble the refrigerant becomes in the lubricant.Ensure sufficient miscibility of lubricant with the refrigerant to maximize heat exchanger efficiency in the refrigeration circuit and assure required oil return to compressor sump.Optimizing the solubility of the refrigerant in the lubricant in the compressor to ensure fluid film lubrication while minimizingviscous drag.
54 Thermal Stability in HFC PatechDifferent Refrigerants, Different Thermal Test Phenomena
55 Thermal Stability in Low GWP Refrigerants Patech
56 Lubricity TestPatechLubricity tests were performed using a high-pressure tribometer and test pieces.When the test was complete, vane wear depth was measured and the antiwear properties of the test oils were evaluated.
57 Life Cycle TestPatechTest RO for characteristic change after running for 2,000 hrs、3,000 hrs、4,000 hrs. (i.e. color, AV, metal, and viscosity).Measure “wear and tear” on compressor parts.
58 P-V-T Charts Comparison PatechGood miscibility of 1234ze lead to lower viscosity and lower pressure
59 Miscibility Comparison (CO2) The miscibility gap of POE is smallest PatechThe miscibility gap of POE is smallest
60 Miscibility Improvement : New Structure Designed Miscibility ProblemPatechMiscibility Improvement : New Structure Designed
61 Low GWP R32 – Our Solution Patech Miscibility RB series & RH series in R32Miscibility RB series & RH series in R410aRB-68-LD-R(20%) : 10℃ RH-68-LD-R(20%) : -50℃