Jet Condenser | Different Types Of Jet Condenser
What is Jet Condenser
Jet condenser is a mixing type condenser where exhaust steam is condensed mix up with cooling water.In a jet condenser, high power is required for condensation. Design of jet condenser is simple.But after condensation, cooling water cannot be used to boiler as it is not free from salt and other impurities.So good quality water is used in jet condenser for condensation.
Advantages and Disadvantages Of Jet Condenser
Advantages Of Jet Condenser:-
1. Design of the jet condenser is simple.
2. Less floor area is required as compared to the other condenser.
3. Price is cheap of this condenser.
Disadvantages Of Jet Condenser:-
1. Vacuum efficiency is low.
2. Pure condensation is not possible.So it can't be reused.
Different Types Of Jet Condenser
According to the direction of flow and arrangement of tubing system, mainly four types of jet condenser is used.
1. Parallel flow jet condenser
2. Counter flow or low level jet condenser
3. Barometric or high level jet condenser
4. Ejector condenser
Parallel-Flow Jet Condenser
As you see in the diagram, exhaust steam, and cooling water enter the top of the parallel jet condenser and mix up together in the condenser shell. This mixture is removed from the bottom of the condenser. Actually, in the condenser, exhausted steam is condensed after mix up with water. The condensate cooling water and air flow's direction is downwards of the condenser and it is separated by two individual pumps which are air pump and condensate pump. A single way air pump is sometimes used for this separation. At the time of separation, a vacuum is created in the condenser chamber. Condensate extraction pump delivers the condensate to the hot well where an overflow pipe is connected to the cooling water tank where surplus water of hot well is stored.
Counter-Flow or Low Level Jet Condenser
In counterflow or low-level jet condenser, exhaust steam enters lower side and cooling water comes upper-side of the condenser chamber, see in the diagram.The direction of exhaust steam is upper-side and cooling water is downwards.Air pump has created a vacuum and it is placed at the top of the condenser shell.The vacuum draws the supply of the cooling water which falls a large number of jets.A perforated conical plate stores this falling water, from which it escapes in second series of jets and meets the exhaust steam entering at the bottom.Condensate and cooling water released for this rapid condensation to discharge the hot well through a vertical pipe by condensate pump.
Barometric or High-Level Jet Condenser
In barometric or high-level jet condenser, a long discharge rod is attached to the lower side of the condenser shell, see in the diagram.Condenser shell arrangement of this type is same as the low-level jet condenser. Exhaust steam enters to the lower side of the condenser and direction of steam flow is upward direction.Cooling water also enters from upwards of the shell and stored at perforated conical plate.Vacuum is created by air pump, placed at the top of the condenser shell.Now steam and cooling water mix up together and discharge hot well through a discharge pipe placed at the bottom of the condenser shell.There is no pump attached in between hot well and discharge pipe. The surplus water store in a cooling tank through an overflow pipe.
In ejector-type condenser, steam and water mix up simultaneously and pass through a series of metal cones.A non-return valve arrangement is arranged for entering the exhaust steam in the condenser shell.Water enters at the top through a number of guide cones.Steam and air pass through the hollow truncated cones.In the cone, kinetic energy is partly transformed to pressure energy.The condensate and discharge to the hot well.