Case Study: Humidi-Tea Perfection at Sabuj Agro Industries Tea Factory

Sabuj Agro Industries tea factory in Bangladesh. Photo: Courtesy of Condair.

“Air humidification is a proven method for enhancing the profitability of a tea production facility.”

The Sabuj Agro Industries tea factory in Bangladesh recently installed a Condair JetSpray humidification system to maintain perfect humidity in its production facility and to ensure the highest quality black tea.

By maintaining a high humidity in the factory, moisture loss from the cut tea leaves is significantly reduced. This improves the fermentation process, resulting in a blacker, more flavorsome tea with improved liquor characteristics and a higher market value, according to Condair.

Condair’s representative in India, Regent Machine & Servicing, managed the design of the humidification system along with its supply and installation. Jaydeep Dasgupta, managing director at Regent Machine, said, “Air humidification is a proven method for enhancing the profitability of a tea production facility. By maintaining a high ambient humidity with a JetSpray humidifier, moisture loss from the tea is virtually eliminated during fermentation. As the moisture content in the tea leaf is kept higher, the chemical reactions that occur during oxidation are enhanced, producing a product with a better final taste, strength and color."

Dasgupta added, “Most CFM machines have built-in humidifiers that pass humidified air through the tea from below. However, these systems are not adequate to prevent drying, particularly from the layer on the top, which is exposed to the room’s atmosphere. Losses of up to 10 percent are not uncommon even on humidified CFMs. This moisture loss will inhibit the fermentation process and result in a poorer quality product with a lower value. It also increases the volume of secondary refuse tea, as more tea degrades from being granular to dust during production.”

The JetSpray humidifier consists of a control panel and a series of nozzles, which can be mounted throughout the area to be humidified, as well as on the in-duct manifold, as a retrofit replacement of the CFM’s original, inefficient in-duct humidifier. The precision engineered nozzles combine compressed air and water, which when released create a fine and highly directional aerosol. The compressed air ensures the moisture rapidly evaporates without any risk of wetting in the area or on machinery within the room. The fan-free design means the JetSpray can operate in very industrial, dusty environments without problems. The nozzles have a self-cleaning mechanism that prevents blockages and the humidifier can operate with any potable water quality without the need for highly filtered, mineral-free water.

The Sabuj Agro Industries tea factory is located in Atwari Upazila, Bangladesh. The system installed at the factory has 32 nozzles humidifying the air to 75-80 percent RH in the CTC area, and 60 nozzles maintaining 90-95 percent RH in the fermentation area. In total, the complete system is capable of providing up to 678 liters of humidity per hour to the atmosphere inside the factory. Sabuj Agro’s owner decided to invest in the JetSpray – and replace an existing spinning disc system – after seeing the JetSpray successfully controlling the humidity at the nearby Bajrang tea factory located, across the border in West Bengal, India.

The Condair Group is a specialist in humidification and evaporative cooling, with energy efficient, hygienic and innovative technologies for commercial, industrial and heritage applications.

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