A high pressure motive fluid, typically steam, enters the steam ejector and passes through the nozzle. During operation, the shock wave may move downstream upon reduction in the condenser pressure. Virtually maintenancefree with no moving parts, they can be fabricated from. Steam jet vacuum ejectors remove gases andor vapours from process operations thereby generating a vacuum in the reactor. A vacuum ejector uses steam pressure to draw air out of the vacuum pipe and reservoirs of continuous train brake. Pdf chemical engineering drawing symbols phuong vy. Working principle of steam ejector power plant tutorials. Steam jet ejectors are mass flow machines that are ideally suited for extracting and compressing noncondensable gas from a condenser operating at high vacuum. Steam locomotives, with a ready source of steam, found ejector technology ideal with its rugged simplicity and lack of moving parts.
Steam ejectors use steam or gas instead of moving parts to compress a gas. Steam jet ejectors offer a simple, reliable, lowcost way to produce vacuum. The mixture then enters to an inter condenser where the steam is condensate. Transvac design and manufacture a comprehensive range of steam jet ejectors from coarse vacuum single stage units. The inter condenser are designed with a special inter condenser baffles of tubes where heat transfer takes place. This condition occurs as the pressure compression ratio p m p v is greater than 1. Through this nozzle, its velocity increases and consequently low pressure exists at that point on nozzle. In a steamjet ejector, the suction chamber is connected to the vessel or pipeline that is to be evacuated under vacuum.
The suction flow is compressed to a higher pressure. They are especially effective in the chemical industry where an onsite supply of the highpressure motive gas is available. Ejectors are considered an alternative to mechanical vacuum pumps for a number of. The mixture leaves the ejector at a pressure p s that is intermediate to the motive p m and suction p v pressures. Steam jet ejectors are used in the process, food, steel and allied industries in connection with such operations as filtration, distillation, absorption, mixing, vacuum packaging, freeze drying, dehydrating and degassing. Steam jet ejectors are used in the process, food, steel and allied industries in connection with such operations as filtration, distillation, absorption, mixing, vacuum packaging, freeze drying, dehydrating. The steam or air converts that pressure or potential energy to velocity or kinetic energy. In a jet or ejector, a relatively highpressure gas, like steam or air, expands through a nozzle. A steam ejector basically comprises of three 3 elements. The steam jet ejector is designed to operate at the critical condition, where the supersonic shock wave is located at the nozzle exit. Graham corporation ejector efficient operation youtube. However, the energy efficiency of steam jet ejectors is significantly less than a mechanical compressor.