Refrigerants play an extremely important role in many different fields. Especially in the field of thermal engineering, which provides thermal equipment for other fields. Refrigerant appears in most airconditioning equipment, refrigeration systems, and deepcooling equipment such as storage, freezing, making ice,… In those systems, the refrigerant acts as a “blood vessel of the system” together with the compressor is the “heart of the system” and make that system magically control the temperature. It is the key component that helps the system to perform heat transfer, which is the miracle that enables temperature control. As a thermal engineering learner, we need to thoroughly understand refrigerant. We need to know about the classification, how it mumbered, how it works in systems, we also need to know about it’s toxicity, flammablity and it’s consequences on the environment and our health. So that we can choose the refrigerant wisely, suitable for the system and balace between cost and health but minimize as much as possible the natural environment affected . So that is the reason why we choose this topic
Ho Chi Minh City University of Technology and Education FACULTY FOR HIGH QUALITY TRAINING SUBJECT REPORT: THERMAL MATERIALS TOPIC: REFRIGERANT INSTRUCTOR : STUDENTS NAME : Ho Chi Minh City, 24/11/2020 STUDENT ID: Feedbacks of lecturer Mark: …………………………… Signature TABLE OF PREPARATIONS No Name ID Preparations Making report file, powerpoint slides, Presentation chapter 1,3 Making report file, powerpoint slides, Presentation chapters 2,4 Outline INTRODUCTION CHAPTER I: Definition and Classification of Refrigerant……………………….1 Definition………………………………………………………………….… … Mumbering…………………………………………………………………… Classification………………………………………………………………….… 3.1 According to the Chemical properites…………………………….….……2 3.1.1 Halocarbons or freons…………………………………………… … 3.1.2 Azeotropic refrigerants………………………………………… … 3.1.3 Zeotropic refrigerants………………………………………… ….…4 3.1.4 Inorganic refrigerants………………………………………… ….…4 3.1.5 Hydrocarbon refrigerants……………………………………… … 3.1.6 Hydrofluoro-olefins…………………………………………… …… 3.2 According to the Flammability and Toxicity……………………… …… 3.2.1 According to Flammability……………………………………… …5 3.2.2 According to Toxicity…………………………………………… … 3.2.3 According to Flammability and Toxicity……………………… … 3.3 According to the Saturated pressure and temperature…………… …… SUMARY………………………………………………………………… …… CHAPTER II: Properties of Refrigerant…………………………………… …… Chemical properties…………………………………………………….……… Physical properties……………………………………………………… …… CHAPTER III:Some commonly used and applications of refrigerants… ….… 12 Some commonly used refrigerant…………………………………………… 12 1.1 CFCs……………………………………………………………………… 12 1.1.1 R-12……………………………………………………………… …12 1.2 HCFCs…………………………………………………………………… 14 1.2.1 R-22………………………………………………………………… 14 1.3 HFCs……………………………………………………………………… 16 1.3.1 R-134a…………………………………………………………….… 16 1.3.2 R-404a…………………………………………………………….… 18 1.3.3 R-407c…………………………………………………………….… 19 1.3.4 R-410a…………………………………………………………….… 21 1.3.5 R-32……………………………………………………………….… 22 1.4 HCs……………………………………………………………………….…23 1.4.1 R-600a……………………………………………………………… 23 1.4.2 R-290………………………………………………………………….25 1.5 Inorganic refrigerants.…………………………………………………….26 1.5.1 R-717 (Ammonia)……………………………………………………26 1.5.2 R-718 (Water)…………………………………………………….….28 Applications of Refrigerant ………………………………………………… 29 2.1 In thermal engineering feild………………………………………………29 2.1.1 In civil refrigeration systems……………………………………… 29 2.1.2 In industrial refrigeration systems…………………………………30 2.2 In other feilds………………………………………………………………31 2.3 Calculate Circulation amount of refrigerant…………………………….32 CHAPTER IV: Global issues caused by refrigerants and solutions……………33 REFERENCES……………………………………………………………… … 34 INTRODUCTION Reason for choosing topic Refrigerants play an extremely important role in many different fields Especially in the field of thermal engineering, which provides thermal equipment for other fields Refrigerant appears in most air-conditioning equipment, refrigeration systems, and deep-cooling equipment such as storage, freezing, making ice,… In those systems, the refrigerant acts as a “blood vessel of the system” together with the compressor is the “heart of the system” and make that system magically control the temperature It is the key component that helps the system to perform heat transfer, which is the miracle that enables temperature control As a thermal engineering learner, we need to thoroughly understand refrigerant We need to know about the classification, how it mumbered, how it works in systems, we also need to know about it’s toxicity, flammablity and it’s consequences on the environment and our health So that we can choose the refrigerant wisely, suitable for the system and balace between cost and health but minimize as much as possible the natural environment affected So that is the reason why we choose this topic! Objectives of the study Know the definition and classification of refrigerant, learn how refrigerant work in system and it affect its impact on the environment As well as learn about the application of refrigerant in the thermal engineering industry separately and other feilds in general After complete the topic, have some basic knowledge about refrigerants Research methods Synthesize and select sources related to refrigerants from Internet, books and lecturers as well as our knowlege TOPIC: REFRIGERANT CHAPTER I DEFINITION AND CLASSIFICATION OF REFRIGERANT Definition A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration cycle In most cycles it undergoes phase transitions from a liquid to a gas and back again The refrigerant acts as a “blood vessel of the system” together with the compressor is the “heart of the system” It is the key component that helps the system to perform heat transfer, which is the miracle that enables temperature control Figure1: Refrigeration cycle [1] Mumbering The numbering of refrigerants is based on the original numbering system for fluorocarbons, which was developed in the 1930s by DuPont and adopted by the entire field in 1956 Since then, it has also been accepted in the ANSI/ASHRAE system as part of Standard 34 (Number Designation and Safety Classification of Refrigerants) The numbering system provides technicians and engineers with an easy way to identify the chemical composition of a refrigerant Each number in the system has its own meaning in the identification of the compounds that form the refrigerant The basic structure begins with the “chemical group” of the substance, followed by a dash (-) and a string of numbers and letters The dash is also commonly omitted For example, HFC-134a consists of the group identifiers “HFC” and “134a”, indicating the chemical composition of the substance Simply the identifying letter “R” is also often used instead of the chemical group, in which case HFC-134a becomes R-134a SUBJECT REPORT : THERMAL MATERIALS TOPIC: REFRIGERANT GROUPING OF REFRIGERANTS : 000 series: methane-based compounds 100 series: ethane-based compounds 200 series: propane-based compounds 300 series: cyclic organic compounds 400 series: zeotropes 500 series: azeotropes 600 series: organic compounds 700 series: inorganic compounds 1000 series: unsaturated organic compounds For example, HCFC-22 is in the “000 series” of refrigerants, meaning it is a methane-based compound R-134a is in the “100 series” of refrigerants, meaning it is an ethane-based compound R-290 is part of the 200 series of propane-based compounds, etc Classification There are thousands of different refrigerants, every year manufacturers nonstop invent new refrigerants to improve the effectiveness.and so there are many ways to classify refrigerants In this report we only mention three common way to classify a refrigerant To facilitate the selection of refrigerants, they often classify them into these type: According to Chemiscal element According to Saturated pressure and temperature According to The flamability and toxicity 3.1 According to Chemiscal element Based on the chemical elements present in the refrigerant, they can be classified into many different types of refrigerants The most common types of refrigerants in use nowadays: Halocarbons or freons Azeotropic refrigerants Zeotropic refrigerants Inorganic refrigerants Hydrocarbon refrigerants Hydrofluoro-olefins 3.1.1 Halocarbons or freons Halocarbons (or freons) are generally synthetically produced Depending on whether they include chemical elements hydrogen (H), carbon (C), chlorine (Cl) and florine (F) they are named after as follows: CFCs (Chlorofluorocarbons): R-11, R-12, R-113, R-114, R-115,… HCFCs (Hydrochlorofluorocarbons): R-22, R-123,… HFCs (Hydrofluorocarbons): R-134a, R-404a, R-407C, R-410a,… SUBJECT REPORT : THERMAL MATERIALS TOPIC: REFRIGERANT 3.1.1.1 CFCs (Chlorofluorocarbons) These are substances containing CARBON, FLORINE and CHLORINE chemicals The CFC refrigerant is now totally banned from use or production within all countries covered by the Montreal Protocol CFCs are generally characterised by a big ODP ( ODP values range from to 1: the closest the ODP value is to 1, the more harmful the refrigerant is for the ozone layer) value, because they contain chlorine, which is accused of heavily contributing to the Ozone Depletion phenomenon As a result, CFCs have been phased out of use nowadays Example: R-11, R-12, R-113, R-114, R-115,… 3.1.1.2 HCFCs (Hydrochlorofluorocarbons) These are substances containing HYDROGEN, CARBON, FLORINE and CHLORINE chemicals Because of high values of GWP (GWP values range from to several thousands: the bigger the GWP value is, the more harmful the refrigerant is for the global warming effect) In general, HCFC gases are to be banned from virgin use from Jan 2010 The general phase out shall be complete by 2015 unless the dates are brought forward Example: R-22, R-123,… 3.1.1.3 HFCs (Hydrofluorocarbons) These are substances containing HYDROGEN, FLORINE and CARBON chemicals The HFC gases are used extensively in every day RAC (Refrigeration and Air Conditioning) systems There is no current ban upon these gases but responsible use and equipment inspections is mandatory under the "F gas" (gas contain Florine) regulations The HFC refrigerants have no ozone depletion potential, but act as a green house gas Only the chlorine free (zero ozone depletion) HFCs are allowed for use nowadays Example: R-134a, R-404a, R-407C, R-410a,… 3.1.2 Zeotropic refrigerants A zeotropic mixture, or non-azeotropic mixture, is a mixture with components that have different boiling points For example, nitrogen, methane, ethane, propane, and isobutane constitute a zeotropic mixture Individual substances within the mixture not evaporate or condense at the same temperature as one substance In other words, the mixture has a temperature glide, as the phase change occurs in a temperature range of about ÷ (℃), rather than at a constant temperature On temperaturecomposition graphs, this temperature glide can be seen as the temperature difference between the bubble point and dew point For zeotropic mixtures, the temperatures on the bubble (boiling) curve are between the individual component's boiling temperatures When a zeotropic mixture is boiled or condensed, the composition of the liquid and the vapor changes according to the mixtures's temperature-composition diagram SUBJECT REPORT : THERMAL MATERIALS TOPIC: REFRIGERANT Zeotropic mixtures have different characteristics in nucleate and convective boiling, as well as in the organic Rankine cycle Because zeotropic mixtures have different properties than pure fluids or azeotropic mixtures, zeotropic mixtures have many unique applications in industry, namely in distillation, refrigeration, and cleaning processes Examples of zeotropic mixtures : R-404a : R-125/143a/134a (44%,52%,4%) R-407c : R-32/125/134a (23%, 25%,52%) R-410a : R-32/125 (50%, 50%) 3.1.3 Azeotropic refrigerants An azeotrope or a constant boiling point mixture is a mixture of two or more liquids whose proportions cannot be altered or changed by simple distillation This happens because when an azeotrope is boiled, the vapour has the same proportions of constituents as the unboiled mixture Because their composition is unchanged by distillation, azeotropes are also called constant boiling point mixtures Some azeotropic mixtures of pairs of compounds are known, and many azeotropes of three or more compounds are also known In such a case it is not possible to separate the components by fractional distillation There are two types of azeotropes: minimum boiling azeotrope and maximum boiling azeotrope Each azeotrope has a characteristic boiling point The boiling point of an azeotrope is either less than the boiling point temperatures of any of its constituents (a positive azeotrope), or greater than the boiling point of any of its constituents (a negative azeotrope) Typical examples of azeotropic mixtures can be seen below: R-502 : 8.8% R-22 and 51.2% R-115 R-503 : 40.1% R-23 and 59.9% R-13 3.1.4 Inorganic refrigerants Inorganic refrigerants consists of inorganic compounds (which does not contain carbon-hydrogen bond) used primarily as refrigerants such as R-718, 717, and 744 Majority of these refrigerants are non-toxic and are environment friendly, inexpensive and non-flammable The report “Global Inorganic Refrigerants Market” analyzes the inorganic refrigerants market by type with respect to three major types such as ammonia, carbon dioxide, and water Used primarily as refrigerants such as: R-718 (H20) R-717 (NH3) R-744 (CO2) 3.1.5 Hydrocarbon refrigerants Depending on whether they include chemical elements hydrogen (H), carbon (C) Hydrocarbon Refrigerants are natural, nontoxic refrigerants that have no ozone depleting properties and absolutely minimal global warming potential The most efficient and environmentally safe refrigerants in the world are the five natural refrigerants which are Air, Water, Carbon Dioxide, Ammonia and Hydrocarbons SUBJECT REPORT : THERMAL MATERIALS