Thermocompressors reduce steam consumption at low temperature ranges, help reduce line steam

Equipment provides reclamation and reuse of heat energy important to an efficient ethanol production process
By | August 01, 2002
Customer: Plant design-builder

Date: August 2002

Background: Since 1991, Broin & Associates, Inc. of Sioux Falls, S.D. has been a key player in ethanol plant design and construction. Working with Broin & Associates, Croll Reynolds Company, Inc. of Westfield, N.J., has supplied its high performance vacuum ejector systems to the ethanol industry.

Steam ejectors play a vital role in the evaporation process, and multi-nozzle thermocompressors improve plant production reliability and efficiency. These thermocompressors provide the reclamation and reuse of heat energy so important to the efficient production of ethanol.

Specifying the Equipment: A thermocompressor is essentially an ejector used to entrain and compress a low-pressure fluid to a reusable pressure/temperature.As stated above, this equipment provides the reclamation and reuse of heat energy vital to an efficient ethanol production process.

Thermocompressors reduce steam consumption at low temperature ranges and are an effective method for achieving significant reductions in line steam consumption. They are also energy saving systems, which require a relatively low capital investment, and are installed with minimal labor.

According to Croll Reynolds, thermocompressors replace pressure regulators or reducing valves in high-pressure steam supply lines. By using high-pressure steam they recompress low-pressure steam to some intermediate pressure and temperature. They may be added to single and multiple-effect evaporators where thermocompressors provide energy savings equiv
alent to the addition of another "effect" at substantially reduced costs. They are also used on flashed condensate recovery systems, reclaiming the heat content in high-temperature conditions.

The Process: Thermocompressors are commonly employed in the evaporator area of an ethanol plant, where thin stillage is concentrated into syrup. Vapor recompression from the multi-nozzle CR thermocompressors is an essential part of the process.

Materials of Construction: The no-moving parts simplicity of a Croll-Reynolds Thermocompressor minimizes maintenance and downtime. They can be fabricated from any workable or weldable material that the user's special needs may demand.

Standard materials of construction for small, single nozzle unit are cast-iron with a stainless-steel nozzle.

Spindle operated and multiple nozzle thermocompressors typically have carbon steel bodies and stainless steel nozzles as standard materials of construction. In spindle operated units, the spindle and spindle guide are also stainless steel.

For most conventional applications, these materials will withstand abrasion and corrosion resulting from the passage of steam at supersonic speeds through the basic body and the stainless steel nozzle. However, where highly corrosive conditions exist, or where special industry requirements demand (as in the food industry), units can be fabricated entirely of stainless steel or from hastelloy, titanium and other exotic alloys.

Since the user is best qualified to determine the corrosive properties of the process gas in his application, materials of construction are normally specified by the customer, Croll-Reynolds Company will, of course, offer its technical input based upon their experience in the design and manufacture of steam ejectors and similar equipment for the process industries.