Case study · New Zealand
Main air heater retrofit
for a new process duty.
A major dairy producer modernised its main air heater with 24 custom-designed heat exchangers, while retaining the existing insulated housing.
Integrated engineering of the heat exchangers, steam supply, condensate and flash steam systems — through to commissioning support.
The challenge
New operating conditions.
Existing space constraints.
Changes to the air treatment process, including the use of a desiccant dehumidifier, changed the inlet conditions of an existing main air heater. The heat exchangers and the connected steam and condensate systems needed to be reassessed together.
Anytherm developed a retrofit around the available space, retaining the existing insulated housing while renewing the heat exchange technology and adapting the wider thermal system.
Project at a glance
Customer
Major dairy producer in New Zealand
Project
Main air heater retrofit · 2021–2022
Scope
Engineering, heat exchanger supply, process integration and commissioning support
The retrofit
Keep the housing.
Renew the thermal system.
24
New heat exchangers
4
Parallel air streams
250,000 kg/h
Total process air design flow · up to
23.5 barg
Existing steam supply cases · up to
30 barg
Future steam supply cases · up to
32 barg
Maximum allowable pressure · steam sections
The replacement heat exchanger banks were engineered to fit the dimensions of the existing installation. Each of the four parallel units contains four steam stages, one flash steam stage and one condensate stage.
16 steam heat exchangers
The main heating duty, designed for the required operating and load cases.
4 flash steam heat exchangers
Recovery of available heat from flash steam within the process conditions.
4 condensate heat exchangers
Further use of thermal energy from condensate to heat process air.
Integrated engineering
Designed as one coordinated system.
Steam and condensate integration
The project included substantial engineering of the steam supply, condensate drainage and flash steam circuits, alongside the thermal and mechanical design of the new heat exchangers.
Where the main air heater could not use all available flash steam under the changed conditions, the concept provided for useful heat recovery in another process.
Prepared for future requirements
The design covered existing steam supply cases up to 23.5 barg and future cases up to 30 barg, depending on the operating conditions. The future maximum-airflow, maximum-duty case uses 25 barg. The steam sections have a maximum allowable pressure of 32 barg. Operating, control and safety concepts were developed for the different production and load conditions.
Anytherm also supported pipework planning, design reviews and coordination of the equipment interfaces.
Certification for New Zealand
The pressure equipment was designed to PED 2014/68/EU and AD 2000. To meet the project’s New Zealand requirements, Anytherm coordinated additional inspection and individual conformity assessment under PED Module G by TÜV SÜD (Notified Body 0036), recognised by WorkSafe New Zealand for this project. This brought the European design and manufacturing documentation together with the required local acceptance route.
Original project photographs
From finished heat exchangers
to the installation on site.
Photographs from factory preparation and commissioning show the replacement heat exchanger elements and their integration into the existing process.
From engineering to operation
Support through commissioning.
Anytherm coordinated engineering, manufacture, certification and international delivery of the heat exchangers. During commissioning in New Zealand, its engineers supported the team in adjusting and optimising the operating parameters.
Customer feedback reported that the targeted production throughput and energy savings were achieved. The feedback also highlighted the technical solution, progress reporting, delivery and support during commissioning.
“We have just recently completed a replacement / upgrade of a large air heater coil radiator. Anytherm AG were contracted to provide engineering for the new design of both the radiator section along with the steam supply and condensate systems.
Anytherm worked extremely well with the rest of the design team on this project. They provided a robust solution and engineering throughout the design phase; this gave us the confidence to proceed with them through to the build stage. Anytherm provided very good, up-to-date progress reporting that led through to the delivery of the equipment on time and without issues.
Anytherm were then on site for the commissioning phase, providing engineering expertise to enable the commissioning team to optimise the running parameters that meet both the throughput and energy savings that we were targeting.
The Anytherm team were great to work with, providing an extremely professional service. I would without hesitation recommend Anytherm AG to anyone and would not hesitate to use Anytherm AG again.”
Senior Engineering Projects Manager
Major dairy producer in New Zealand
Customer testimonial · anonymised
Your existing plant. New possibilities.
Planning a heat exchanger retrofit?
Talk to our team about changed process conditions, existing space constraints and the integration of new heat exchangers into your plant.