No more machine downtime in Carel’s in-room solution

Ferrarelle SpA deals with the bottling and distribution of mineral waters, both nationally and internationally. This industrial production process requires relative humidity to remain above a certain threshold, so as to prevent evaporation of the water contained in the lubricant used to run the bottles along the conveyor belts. If humidity is too low, the water evaporates causing the bottles to fall off the lines. This means machine downtime and a consequent decline in efficiency.

At its Darfo Boario Terme plant, in northern Italy, problems were found in the production lines due to excessively low relative humidity. The chosen solution was an in-room humidification system, which both meets the requirements and achieves the desired objectives.

From collection to delivery of the water
The various stages in the process include the production of plastic bottles using PET (polyethylene terephthalate) preforms, bottling and closing, labelling, packaging and storage. Special conveyor belts move the products between the different stations on the production line; these are constantly lubricated so as to ensure correct flow of the bottles, placed upright and close to each other. If humidity is low, the properties of the lubricant degrade and the bottles overturn; the machinery then needs to be stopped so as to return them to the correct position. Consequently, it is essential to maintain relative humidity above 35 per cent, to avoid production line stoppages.

In-room adiabatic humidification
The plant covers an area of about 50 x 70 m. The AHUs installed for air change have fabric distribution ducts, and therefore a ducted humidification system was not possible. Carel, thus proposed an in-room system, comprising a pumping station with a capacity of 80 l/h, and five blowers, divided into two zones. The required set point is around 45 per cent for relative humidity and between 15-18°C for the temperature. The winter months are the most critical, as outside temperatures are low and relative humidity falls significantly due to the air being heated before entering the production area.
This is therefore the period with the highest humidification load needed to reach the desired conditions.

The humidifier can be controlled remotely via BMS, and receives a relative humidity signal from a sensor that was already installed in the plant. The humidifier only starts when the air handling unit is operating. The set point was set at 45 per cent, with a 5 per cent band, with humidity production thus modulated close to the set point so as to guarantee excellent precision. The water is atomised into small droplets that evaporate naturally when coming into contact with the air; the end result is humidification of the air until reaching the desired conditions.

Complete and efficient solution
As humidification is direct, correct design of the installation is essential, and was carefully evaluated by Carel personnel. The humidification system was installed in the most critical area of the plant, where the main production lines are located.

The pumping station, on the other hand, was installed close to the equipment compartment for convenience in terms of installation, wiring and maintenance.

Conclusions
The humiFog direct humidifier allows the specific requirements to be met without significant structural requirements for installation. The five blowers distribute the humidification load according to actual needs. The desired environmental conditions are achieved with low operating and maintenance costs. Electronic control guarantees high performance and flexibility, making humiFog direct the best solution for the case in question.

For more details, visit:
www.carel.com