Improving the efficiency of evaporation plants that produce condensed milk by applying liquid-vapor jet units

This study's object is the evaporation unit that produces condensed milk. The problem of low efficiency of evaporation units producing condensed milk has been solved by replacing steam jet ejectors with fundamentally new two-phase jet devices represented by liquid-vapor jet units. Their operational process is based on a jet thermocompression principle, which makes it possible to reduce the consumption of boiler steam, which is used in steam jet ejectors as a working jet of active flow. In liquid-vapor jet devices, boiler steam is used only to heat the working fluid of the active flow in a heat exchanger-heater. Given this, it is possible to reduce its consumption by 2.95 times and achieve the economic effect averaging USD 1,337. Another advantage of liquid-vapor jet units is that the generation of working steam occurs in the supersonic part of the active flow nozzle. As a result, it is possible to improve the degree of increase in the pressure of the secondary flow and abandon its multi-stage compression as is implemented in steam jet ejectors. This further increases the efficiency of installations based on such units by 25–30% compared to steam jet ejectors. And, most importantly, the use of liquid-vapor jet devices makes it possible to simplify the design of the evaporation unit and switch from a two-case to a single-case scheme. This provides a reduction in the cost of a product unit by an average of USD 450 per ton. This paper reports the thermodynamical, exergy, and thermoeconomic analyses. As a result of the study, it was found that the modernization of evaporation units that produce condensed milk by using liquid-vapor jet unit makes it possible to improve the efficiency of such systems by 2.1 times on average