However, the energy efficiency of steam jet ejectors is significantly less than a mechanical compressor. The second stage ejector handles the non condensate gasses of first stage ejector and through a vent opening to the atmosphere. The steam or air converts that pressure or potential energy to velocity or kinetic energy. 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. Virtually maintenancefree with no moving parts, they can be fabricated from.
The suction flow is compressed to a higher pressure. In a jet or ejector, a relatively highpressure gas, like steam or air, expands through a nozzle. Through this nozzle, its velocity increases and consequently low pressure exists at that point on nozzle. Graham corporation ejector efficient operation youtube. The inter condenser are designed with a special inter condenser baffles of tubes where heat transfer takes place. Working principle of steam ejector power plant tutorials. Ejectors are considered an alternative to mechanical vacuum pumps for a number of. Steam jet vacuum ejectors remove gases andor vapours from process operations thereby generating a vacuum in the reactor. In a steamjet ejector, the suction chamber is connected to the vessel or pipeline that is to be evacuated under vacuum. Transvac design and manufacture a comprehensive range of steam jet ejectors from coarse vacuum single stage units. 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. 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 ejectors use steam or gas instead of moving parts to compress a gas. Compared with other mechanical compressors, steam jet ejectors offer the benefits of no moving parts and low cost. Steam jet ejectors, the largest vacuum producing devices available are used in the most demanding of applications. Steam locomotives, with a ready source of steam, found ejector technology ideal with its rugged simplicity and lack of moving parts. The steam jet ejector is designed to operate at the critical condition, where the supersonic shock wave is located at the nozzle exit. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Pdf chemical engineering drawing symbols phuong vy. A vacuum ejector uses steam pressure to draw air out of the vacuum pipe and reservoirs of continuous train brake. They are especially effective in the chemical industry where an onsite supply of the highpressure motive gas is available. A steam ejector basically comprises of three 3 elements. This condition occurs as the pressure compression ratio p m p v is greater than 1. During operation, the shock wave may move downstream upon reduction in the condenser pressure. A high pressure motive fluid, typically steam, enters the steam ejector and passes through the nozzle.
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