Skip to main content

Construction and Working of Ammonia - Water system in Vapor Absorption System :

 I) AMMONIUM WATER SYSTEM :

An Ammonium - water refrigeration system uses ammonia as refrigerant with water as absorbent.




WORKING OF THE SYSTEM :

* After expansion in the valve, the liquid refrigerant enters the evaporator. There, it absorbs heat from the place to be refrigerated. Its phase changes from liquid to vapor.
* Then, the vapor reaches absorber where it is readily absorbed in a low temperature absorbing medium. So, it mixes with the weak solution, thus the solution now becomes strong. Some heat being rejected during the process.
* This strong solution is pumped to the high pressure and passes through heat exchanger. Here, it takes some heat from the weak solution which is throttled and returning back to the absorber. This    increases the efficiency of  the system.
* Generator heats the strong solution, thereby forming Ammonia vapor. During heating, some water  may also be vaporized. This water vapor is separated in the analyzer.
* Even after this, if any water vapor is present, that will be condensed in the rectifier, by passing cooling water.
* Now, only pure ammonia vapor enters the condenser and cooling water is passed through the condenser. Because of the condensation refrigerant vapor becomes liquid and this liquid goes to the receiver. Thus the cycle continues. 

Comments

Popular posts from this blog

MELTING FURNACES FOR FERROUS METALS : CUPOLA AND ITS WORKING

Various types of melting furnaces are used in different foundry shops, depending upon the quantity of metal to be melted at a time, and the nature of work that is carried out in the shop.  The primary objective in cupola is to produce iron of desired composition, temperature and properties at the required rate in the most economical manner. Besides, this furnace has many distinct advantages over the other types, e.g., simplicity of operation, continuity of production, and increased output coupled with a high degree of efficiency.  Description Of a Cupola : The Cupola Furnace consists of a vertical, cylindrical steel sheet, 6 to 12 mm thick, and lined inside with acid refractory bricks or acid tamping clay. The refractory bricks or the tamping clay used consist of  silicon oxide acid (SiO2) and alumina (Al2O3). The lining is generally thicker in the lower where the temperatures encountered are higher than in the upper region. The shell is mounted either on a brick work fo...

SIMPLE CARBURETOR - CONSTRUCTION AND WORKING

CONSTRUCTION OF SIMPLE CARBURETOR :  The main Components of Simple Carburetor are : Float Chamber, float, nozzle, venturi, throttle valve, inlet valve, and metering jet . In the float chamber, a constant level of petrol is maintained by the float and a needle valve.  The float chamber is ventilated to atmosphere.  This is used to maintain atmospheric pressure inside the chamber. The float which is normally a metallic hollow cylinder rises and closes the inlet valve as the fuel level in the float chamber increases to certain level. The mixing chamber contains venturi, nozzle and throttle valve. The venturi tube is fitted with the inlet  manifold. This tube has a narrow opening called venturi. A nozzle is provided just below the centre of this venturi. The nozzle keeps the same level of petrol as that of the level in the float chamber. The mixing chamber has two butterfly valves.  One is to allow air into the mixing chamber known as choke valve. The other is to al...

Advantages And Disadvantages Of Air Refrigeration System :

 Advantages Of  Air Refrigeration : 1. The refrigerant used namely air is cheap and easily available. 2. There is no danger of fire or toxic effects due to leakages. 3. The weight to ton of refrigeration ratio is less as compared to other systems. Disadvantages Of Air Refrigeration : 1. The quantity of  Refrigerant used per ton of refrigeration is high as compared to other systems. 2. The COP of the system is very low. Therefore running cost is high. 3. The danger of frosting at the expander valves is more as the air contains moisture content.