The FT74XA is compact, mobile and easy to install. It has an integral pressurized hot water generator and requires only electricity and cooling water to operate making it ideal for confined spaces with limited services such as laboratories.
Operation with either plate or tubular heat exchangers means a wide range of product viscosities can be handled. A progressive cavity feed pump ensures that flow rates are independent of viscosity / backpressure changes and allow a maximum operating pressure of 10 bar.
Typical processing flow rates are 10-20 L/h with holding temperatures up to 150°C. At pasteurization temperatures flow rates of up to 60 L/h are achievable.
Cleaning is in place (CIP) using the feed pump in high flow rate mode and there is a centrifugal pump CIP option (FT74-52) which generates very high cleaning velocities to deal with products that are particularly difficult to clean.
Sterilization (SIP) of the system is controlled from the touchscreen. System sterilization time and temperature are defined and key temperature sensors are monitored to ensure the entire system satisfactorily completes the SIP cycle.
Automatic pre-heat control (FT74-46) offers an independent hot water circuit and the product pre-heat temperature is set via the touchscreen.
The system is well instrumented for both process and services with all sensors displayed on the touchscreen and recorded values can be seen graphically and saved to USB datastick for further analysis.
The FT74-30-MkIII is the standard plate heat exchanger, comprising a regeneration section, a heating section and a cooling section. It is based on miniature 316 stainless steel plates specifically developed for this application. The chevron pattern mimics the turbulence and shear rate of industrial-scale systems. Holding tubes of 2s and 15s (@10l/hr) are provided as standard.
A number of options can be provided to enhance the performance of the standard plate heat exchanger. These options involve additional plate configurations and are easy to retrofit by the user.
The FT74-31 Homogeniser interconnecting plate can be fitted into the regeneration section and permits connections to an upstream (ie before heat treatment) homogeniser to be made. It includes a temperature sensor on the homogeniser return, which can be displayed on the FT74-44 data logger. The FT74-32 Homogeniser interconnecting plate enables the homogeniser to be connected after the heat treatment (downstream).
Note: only one interconnecting plate can be fitted at a time.
The FT74-33 Two-stage cooling option provides a complete additional cooling stage. The second cooling stage can be used in conjunction with a chilled water/glycol supply (eg Armfield FT63) for the best possible product cooling. Output temperatures below 5°C are possible, dependent on the product and the flow rate. An interconnecting link is provided to permit single-stage cooling.
The FT74-34 Additional heating option provides extra plates in both the heating and regeneration sections. This is useful for difficult products at high temperatures, or where higher throughputs are desired.
The FT74-20-MkIII is the standard tubular heat exchanger, and uses a series of concentric 316 stainless steel tubes to heat and cool the product. A gentle preheat can be achieved by adjusting the hot water flow to the first two tubes. Four further heating tubes are used and both 2s and 15s (@ 10 l/hr) holding tubes are provided as standard.
The four cooling tubes can be used either as a single cooling stage, or split into two stages of two tubes each for enhanced cooling when used in conjunction with a cooling water supply and a chilled water/glycol supply (eg Armfield FT63). The FT74-20-MkIII can be upgraded to the FT74-24-MkIII (below) at a later date.
The FT74-24-MkIII is an extended version of the FT74-20-MkIII, with a total of eight cooling tubes (4+4). When used with a chilled water/glycol supply on the second four tubes, and with the static mixer options, this heat exchanger can give product output temperatures below 10°C, dependent on product, flow rate and processing temperature.
The FT74-21 is a set of static mixers for two tubes, and can be used with either tubular heat exchanger to improve the heat transfer. This is particularly useful when trying to get maximum heating or cooling with viscous products. Multiple sets can be used to optimise both heating and cooling performance. Additional static mixers can be added at any time.
When working with particulate products and the tubular heat exchanger, the standard mechanical back pressure valve can be replaced by the FT74-22 to give much more stable flow and back pressure. (Requires a supply of compressed air).
The FT174-41 is used in place of the feed hopper. The suction feed assembly allows the system to be connected to a feed tank. The assembly includes an in-line level sensor to protect the feed pump from running dry.
The FT74-45 is an additional heat exchanger, which can be used with the FT74-20-MkIII or FT74-30-MkIII to sterilise the complete system including the cooling section. The heating power is derived from the hot water boiler used in the FT74XTS. It can also be used to link to and sterilise an aseptic filler such as the Armfield FT83.
Note: If using an in-line homogeniser, the additional cooling tubes of the FT74-24-MkIII, or holding times in excess of 45s, then additional measures will be required to completely sterilise the system. Please consult Armfield with your specific requirements.
The FT174-53 adds an automatic water feed to the suction feed assembly (FT174-41). Should a low feed-level situation occur then the unit can switch to a pressurised water feed automatically. This therefore means that the operation of the HTST system is not interrupted.
Comprising three different holding tube coils, packaged together in an insulated canister, the FT74-65 can be easily configured to provide seven different holding times between 30s and 120s (@10 l/hr). Intermediate holding times can be achieved by varying the feed flow rate. The variable holding tube can be used with all the plate and tubular heat exchangers described above. It is supplied with an additional temperature sensor to enable the product temperature from the holding tube to be displayed on the screen.
Platinum resistance (PT100) temperature sensors for high accuracy