New technology helps firm deliver fresh tea in record time

Kaproret tea estate assistant manager Wesley Ngetich.

Sacks after sacks of green tea leaves picked from Kaproret estate are delivered for processing at Kitumbe tea factory points by 11-kilometre loop steel cables rotating.

The cables are suspended toothed pulleys on 40 towers mounted along the carefully selected route. To convey the leaf, four sacks of 12 kg leaf each are placed on colour-coded hangers and mounted onto the rotating steel cable.

This is only on the designated leaf collection points by means of a grip hook.

The return loop is used to return empty hooks and hangers. The cables are usually rotated at a speed of 90 metres per minute by a drive unit powered by a 75kilowatt electric motor with 100 horsepower diesel engine on standby.

Part of the power is harnessed from the 30kW PV solar panels mounted on the drive roof.

This is not some setting in Europe or some other First World country; It is one from a tea factory in the Rift Valley.

Kaproret Tea Estate Assistant Manager Wesley Ngetich said the James Finlay Tea Factory has been using the technology since 2013.

“The company invested in the ropeway as an alternative means of transporting green leaf with an objective of lowering the cost of transport. The other advantages of the system include continuous feed to the factory, less leaf (Mis) handling, leaf aeration on transit and possible carbon credits,” he said.

Mr Ngetich said the construction of the aerial ropes has reduced the numbers of trucks that James Finlays used to transport harvested tea at Kaproret Tea Estate from six to only four.

The construction of the aerial ropeways has also yielded direct benefits to the environment. “The company was able to reduce their carbon index by 10 per cent within the first year – between 2010 and 2011,” said Ngetich.

He noted that the workers and the community around the factory now face fewer risks of pollution as well as traffic hazards.

Installed capacity

The system has also employed over 50 people and more are now employed in the fields due to the ease of transportation.

The 5.5km ropeway route has been selected to pass through as many fields as possible so as to reduce road shunting distances.

Four designated leaf collection points are located along the ropeway. There are two angle stations on the route. The ropeway has an installed capacity of delivering 70 tonnes of green leaf daily to the tea factory for processing. “We have improved our efficiency to 70 per cent thereby delivering up to 50 tonnes on a single day by bridging the gap to as little as 20 metres between hooks during times of peak crop,” said Ngetich.

He said routine maintenance activities include greasing the rope, diesel engine oil and filter change and fluid coupling oil change.

Others are hook checks and replacement, pulley groove filling, tower nuts and bolts tightening among others.

While in use, Ngetich said, each of the two steel cables (rope) run parallel to each other with a design breaking load of 61 tonnes. “It has been skilfully spliced to form a loop and tensioned to 11 tonnes at the turning point,” said Ngetich.

The estate assistant manager explained that green leaf deliveries require a lot of coordination in order not to fault on leaf traceability and the loading sequence.

“Colour coding and loading interval regimes are normally employed. Communication between collection points and the factory is made possible by means of radio calls,” said Ngetich.