Ammonia refrigeration equipment process, the development process of ammonia refrigeration system

Process: The refrigeration process is carried out in a circulating closed system composed of ammonia compressor, cooler, regulating valve, evaporator, etc., and the ammonia liquid enters the evaporator after reducing the pressure through the regulating valve, absorbing the heat of the cooled medium and evaporating, so that the temperature of the medium is reduced to achieve the purpose of refrigeration; The evaporated ammonia is sucked back by the compressor, compressed and discharged to the cooler, so that the ammonia is cooled and condensed into ammonia, and then re-enters the evaporator through the regulating valve to evaporate, so that the purpose of refrigeration is achieved by repeated circulation.

Ammonia machine, the volume is relatively large, installation and maintenance are more troublesome, and ammonia also has a characteristic, can not be in contact with copper, and copper contact will react, copper in heat conduction performance is very superior, now the use of ammonia machine is not very much, but in the cold storage is still more common, because ammonia machine is easy to low temperature.

To fully understand such a large area, it is recommended that you first look up information on the Internet or go to the library, and then ask others if there is anything you don't understand. The principle of the ammonia refrigeration process is that ammonia is easy to liquefy, and liquid ammonia becomes a gas and absorbs a large amount of heat to refrigerate.

Refrigeration is divided into air-conditioning conditions and refrigeration conditions.

Air conditioning conditions The refrigerant in air conditioning conditions is generally freon, because the effect of freon refrigeration is particularly good, but it is harmful to the ozone layer, but there is no refrigerant that replaces the complete freon There is also a reason why freon is used in air conditioning.

Refrigeration conditions refrigeration is generally used ammonia because refrigeration is how many degrees below zero, a large amount of cooling capacity is required, a large amount of refrigerant, and ammonia is not as good as freon refrigeration, but ammonia is much cheaper than freon, and there is no pollution.

1 compression, 2 condensation, 3 throttling, 4 evaporation.

Hello dear, the development process is as follows: American inventor Perkins (}co}i 1i1) working in London in 1834'd) Formally filed a UK patent application for expansion refrigeration of ether in a closed loop. This is the prototype of a vapor compression chiller.

The invention of air chillers came slightly later than vapor compression chillers. American John Gorry (Johng Orrie) introduced his invention of the air chiller, which is the world's first air chiller for refrigeration and air conditioning. The first ammonia absorption chiller was designed and manufactured in Calle, France.

Among the various types of refrigerators, compression refrigerators have developed rapidly. Since the American Boyle invented the ammonia compressor in 1870 and the German Linde (Tirade) built the first ammonia refrigerator, the ammonia compression refrigerator has been widely used in the industry. With the continuous development of refrigeration models, the types of refrigerants have gradually increased, from the early air, carbon dioxide, ether to methane, sulfur dioxide, ammonia, etc.

In 1929, with the advent of freon refrigerants, compression refrigerators developed faster and surpassed ammonia refrigerators in terms of application. Subsequently, the azeotropic mixed refrigerant was used in the Indian period of the 2nd century, and the non-azeotropic mixed refrigerant was used in the 60s of the Canadian century. Until the 80s of the 2d century, before the issue of the phase-out of ozone-depleting substances CR was officially recognized, the development of refrigerants based on various halogenated hydrocarbons had almost reached a fairly complete level.

Hello dear and happy to answer for you. Found for you: Commissioning of ammonia coolers:

The ammonia synthesis reaction is a reversible reaction and a heating reaction, the role of the ammonia cooler can be cooled to make the reaction in the direction of ammonia synthesis, and at the same time, it is used for ammonia liquefaction and separation, so that the products are reduced, and the anti-lead wax should be shifted to the right. The ammonia vapor in the condenser transfers heat to the coolant cooling water, and the ammonia vapor that loses heat is condensed into liquid ammonia; The throttle valve will replenish the liquid ammonia sliding from the condensation to the evaporator in a controlled manner, so that the evaporator can work continuously, which is the whole process of refrigeration. The minimum temperature for cooling is about minus 30 degrees Celsius.

I hope mine can help you and wish you a happy life

The refrigeration principle, structure and operation method of ammonia machine.

Because liquid ammonia has good thermodynamic properties and no adverse effects on the atmosphere, it is widely used in industrial and commercial refrigeration systems as a refrigerant by the global refrigeration industry. In particular, it is most commonly used in large and medium-sized cold stores built to ensure the quality of perishable food (about 80% of the world's large cold stores use ammonia refrigeration systems). Basic knowledge of ammonia refrigeration (1) Physical and chemical properties of ammonia 1

Relative density of gas ammonia (air = 1): 2Liquid ammonia relative density (water = 1):

3.Boiling point:; 4.

**Limit:; 5.According to the definition of the List of Hazardous Chemicals (2002 Edition), ammonia belongs to the first class of toxic gases.

Liquid ammonia is ammonia in a liquefied state, also known as anhydrous ammonia, which is a colorless liquid, corrosive and volatile. It is formed when gaseous ammonia is pressurized, and at the same time releases a large amount of heat, on the contrary, liquid ammonia absorbs a large amount of heat when it evaporates, due to its good thermodynamic properties, liquid ammonia is widely used as a refrigerant in refrigeration systems. According to the Code for Fire Protection Design of Buildings (GB50016-2006), the fire hazard classification of liquid ammonia should be characterized as Item 2 of Category B; The evaporation temperature of liquid ammonia is that once it leaks under outdoor conditions, gaseous ammonia can be formed immediately; There is a risk of burning**; Ammonia can invade wet**, mucous membranes and eyes, and can cause severe coughing, bronchospasm, acute pulmonary edema, and even blindness and death by asphyxiation.

2) Ammonia refrigeration principle: the vapor compression refrigeration cycle consists of four processes: the evaporation of the liquid refrigerant or the isobaric heat absorption of the gaseous refrigerant; compression of refrigerant coarse cavity vapors or gases; liquefaction of refrigerant vapors or isobaric exothermic of gases; Throttling of refrigerant liquids or expansion of gases. The cascade refrigeration cycle consists of two or more independent refrigeration systems.

Different refrigerants are used in each refrigeration system. The evaporator of the high-temperature system is also the condenser of the low-temperature system. The vapor jet refrigeration cycle uses a refrigeration cycle in which the refrigerant vapor is pressed from the evaporator to the condenser, liquefied, throttled, and enothermic evaporated in the evaporator.

Adsorption refrigeration cycle, air refrigeration cycle ......Main equipment and facilities: mainly composed of compressor, condenser, ammonia reservoir, oil separator, throttle valve, ammonia separator, evaporator, intercooler, emergency ammonia drainer, oil collector, various valves, pressure gauge and high and low pressure pipelines. Among them, the compressor, condenser, throttle valve and evaporator (cold storage pipe) in the refrigeration system are the four most basic components.

They are connected by pipes in turn to form a closed system, in which the refrigerant ammonia is constantly circulating, changing the state, and exchanging heat with the outside world. Ammonia refrigeration cold storage: including warehouse, refrigeration room, control room, substation and distribution room, etc.

The schematic diagram of the ammonia cold storage refrigeration system is as follows:

The synthesis process of ammonia refrigerant is mature, easy to prepare, and inexpensive. The pressure of the ammonia refrigerant in the condenser and evaporator is moderate (the condensation pressure is generally, the evaporation pressure is generally; The cooling capacity per unit volume is larger than that of CFC-12 and HCFC-22; The refrigeration coefficient is high, the heat release coefficient is large, and the ammonia compressor is the smallest at the same temperature and the same cooling capacity. Ammonia refrigerants are widely used in large cold storage, supermarket food display cabinets.

Lubricating oil plays the role of lubrication, cooling, washing and energy regulation in the refrigeration system, generally speaking, the oil accumulation in the cooling equipment is the biggest obstacle affecting the refrigeration effect of the ammonia refrigeration system, and may even cause production stoppage. Therefore, it is necessary to investigate the causes and effects of lubricating oil bursting into the cooling equipment and the measures that should be taken in the design and operation.

1. The reason why the lubricating oil enters the cooling equipment in the warehouse.

Lubricating oil plays the role of lubrication, cooling, washing and energy regulation in the refrigeration system, qualified lubricating oil should be used, and defective products should not be used, and the flash point and freezing point of lubricating oil should be strictly controlled to ensure the safe operation of the compressor.

When the machine is running, the temperature of its running parts can not be too high, the maximum oil temperature shall not exceed 70, overheating, to stop the machine to find the cause of the elimination, such as the old oil should be heated, filtered, precipitated before use. When the compressor is running, the temperature of the ammonia gas discharged is very high, generally 70 150 °C, and at this temperature, part of the lubricating oil will evaporate into oil vapor.

The higher the exhaust temperature, the higher the evaporation rate of the oil. The test data show that the evaporation rate of oil at 80 is ; At 100 the evaporation rate of the oil is at 120 The evaporation rate of the oil is ; At 140 the evaporation rate of the oil is .

On the other hand, due to the large speed of the air flow, generally between 12 and 30m s, it also carries a certain amount of oil particles, so it can be considered that the oil enters the high-pressure part of the refrigeration system in the form of gas, fine particles, and even larger balls under the drive of high-temperature ammonia. The ammonia-oil mixture entering the high-pressure part is decelerated in the oil separator, and the ammonia speed is reduced from i2m s, and most of the oil is removed by changing direction or centrifugal force, liquid washing, etc., but there is still 3 5% lubricating oil burst into the heat exchange system. In addition to part of the oil attached to the condenser, pipeline system, liquid reservoir and other equipment, there will still be 1 2% of the lubricating oil into the cooling equipment.

The advantages of ammonia as a refrigerant are: easy to obtain, low cost, moderate pressure, large unit refrigeration capacity, high exothermic coefficient, almost insoluble in oil, small flow resistance, and easy to find when leaking.

His role is refrigeration, and relatively speaking, the importance of this is relatively good, relatively good.

In ammonia refrigeration, the role of ammonia is as a refrigerant, and the refrigerant is the carrier of cold or heat, which can transport the outdoor heat or cold to the room to meet the needs of air conditioning.

The condensed liquid enters the siphon tank first, is connected with the compressor oil cooler through the pipe at the bottom of the siphon tank, and is discharged into the condenser after heat absorption, and the condensed excess liquid is led out into the reservoir in the middle of the siphon tank. Intercoolant is used in bipolar systems.

In this case, the role he plays is to need a refrigeration, and relatively speaking, the effect is relatively good, and its role in it must be paid attention to.

What is the role of resettlement in Fuzhou when the cold rises? This should play a certain role in stability, so let's find out more about the specialty store.

The main parameters of the refrigeration system are the dynamic data of the temperature and pressure of the refrigeration equipment during operation. The parameters of the refrigeration system are: evaporation pressure and temperature, condensing pressure and temperature, cooling temperature, compressor suction temperature, exhaust temperature, intermediate pressure and temperature, etc.

Among them, evaporation pressure and temperature and condensation pressure and temperature are the main parameters.

Understand and be familiar with the changes in the main parameters of the refrigeration equipment at each stage of the operation process. It plays an extremely important role in the reasonable configuration, correct operation and adjustment of the equipment, ensuring safe operation, reducing the consumption of electricity, oil and water, and improving economic efficiency.

Scientific and reasonable safety operating procedures should be formulated and strictly observed. All cryo-safety workers must be certified to work to ensure safe operation.

1. The newly installed refrigeration system must go through the pressure test, leak detection, sewage discharge, and vacuuming, and the refrigerant can be filled when the system is confirmed to have no leakage.

2. When filling the container with refrigerant, the valve opening operation should be carried out slowly to avoid brittle damage to the container.

3. In the refrigeration system, it is strictly forbidden to close the valves at both ends at the same time for the pipeline equipment containing liquid refrigerant.

4. In order to avoid the occurrence of open flames mixed with ammonia and air, there can be no open flames between the freezing station and auxiliary equipment, and it is strictly forbidden to use open flames for heating in winter.

5. When overhauling equipment and pipelines, it is strictly forbidden to disassemble the equipment for welding operations when the refrigerant is not evacuated or replaced and completely connected to the atmosphere.