The sugar cane capital of Australia


 

Sugar cane is a very important agricultural product in Australia and Queensland is the main area you will find it. You will come across the first cane fields in northern New South Wales really. However, the bulk production takes place farther up north on the east coast of Queensland especially in the area of Bundaberg. Here you will see kilometre upon kilometre of sugar cane fields along with the railway tracks for the sugar railway that transports the harvested cane to the mills and distilleries.

Historically, it was the Sydney area right in 1788 where the first attempts of growing sugar cane were made. Unsuccessfully though; the conditions were just too lousy for it. I guess you can say there was Hope for sugar when Captain Lois Hope set up the first viable sugar cane plantation and a raw sugar mill near Cleveland, Brisbane, in the 1860s.

According to a very nice diorama set up by the Lions Club of Home Hill of the Burdekin Shire, this shire in Central Queensland is the undisputed sugar capital of Australia and one of the largest sugar-producing regions in the world. I will just go ahead and believe this to be true and use the excellent display of the Lions Club to tell you more about the sugar cane industry of Australia.

The Burdekin is located in the dry tropics and enjoys a yearly average rainfall of about 1000mm. With its 300 days of sunshine it is a perfect agricultural area. Man’s knowledge about irrigation and the underground aquifer add to the perfection and the farmers make excellent use of the fertile soil. The result is a production of 8.2 million tonnes of cane a year on 80.000 hectares of land. This cane is refined into 1.25 million tonnes of sugar in only four large-scale mills. Overall this accounts for a quarter of Australia’s sugar production. Hence the sugar industry with its associated businesses play a big role in the regional labour sector. Apparently it is worth mentioning that the Burdekin is one of the last regions in Australia that still burns cane before harvest to remove excess leaves. Such cane fires can be seen in the evening or early morning during the months of June to December.

Some herbological and growing information about sugar cane

Sugar cane is a kind of grass and therefore has green leaves, a stalk and roots to collect sunlight, moisture, and carbon dioxide. The food source, a sweet juice containing sugar, is stored in its stalk.

New cane is grown is grown from pieces of cane stalk, called setts, which are planted in furrows, fertilised and then watered. As the young cane grows, the land around it is cultivated to control weeds and to let air and water into the soil. In moist, warm conditions, the cane grows quickly and is usually ready to harvest in 10-18 months. Mature cane stands 2-4 metres high and is traditionally harvested between June and December in the Burdekin. This season is commonly called the crushing because after the harvest the cane is taken to the mill and crushed there to remove its sugar juice.

The harvest

In the past, before there were machines, the harvest was done by hand like with any agricultural harvest. Thousands of cane cutters would swing their cane knives and cut the cane just above the ground. It was a physical demanding job especially in these tropical temperatures. Many if not most cutters were South Sea Islanders, known as Kanakas,who were brought over to Australia as cheap labour. (Btw. Kanakas is where the German xenophobic term Kanakken comes from which used to refer to foreigners coming from Turkey or Southern Europe; not only were we disrespectful and hateful to foreign workers, we had no clue about what we were calling them.)

Until the 1940s, most cane was cut green by hand, with the residual trash brunt on the ground. Then burning became the standard practice to reduce and limit outbreaks of the potentially fatal Weil’s disease. Burning also made harvest faster. Hand cutters were used well into the 1960s and in 1979, Australia became the first sugar-producing nation to convert entirely to mechanical cane harvesting.

To harvest cane, the harvester moves along the rows of cane, removing the leafy tops of the cane stalks. With burnt cane harvesting the green leaves don’t exist anymore. They have been burnt off so only the stalks are left. This is still the preferred method in the Burdekin region because the cane is so high and there would just to much green trash left. The shower of small pieces of burnt foliage which floats from the sky during a cane fire is commonly known as ‘Black Snow’or ‘Burdekin Snow’.

The stalks are cut off at ground level and chopped into short lengths, called billet. These billets are transported from the harvester to a cane railway siding where a mill-owned locomotive will come to collect full cane bins and deliver them to the sugar mills.

After harvesting, the stubbles left behind on the stool of cane still in the ground grows new shoots, producing what is known as a ratoon crop. Two or three ratoon crops can be grown before a paddock is ploughed out and then left fallow for a period, before being replanted with new cuttings for the cycle to start again.

A little bit more information about the railway system: When you take into consideration that we are talking about 80.000 hectares of sugar cane fields you can imagine how big the railway system must be. All over the area you see signs that warn you to pay attention to the trains in harvesting season. Sugar cane must be milled as soon as possible after it is harvested to minimize deterioration and loss of sugar content. That’s why the trains run 24/7. The locomotives can haul up to 200 cane bins in one trip. The whole network of railway lines in the Burdekin covers more than 600km of cane railway tracks.

In case you are interested in how raw sugar is made (all information is directly copied from the diorama)

There are altogether 10 steps in the sugar production. Here we go:

  1. Cane receival

Once harvested cane arrives at the mill, it’s weighed and received at an automated cane-receiving station.

  1. Shredder

The cane billets are tipped out of the cane bin and onto a cane carrier which transports them to a shredder. The shredder shreds the cane into fibrous material.

  1. Extraction station

Pairs of rollers feed the cane through a series of mills. Each mill comprises a series of rollers. This process separates the sugar juice from the fibrous material, called bagasse. The juice is pumped away for processing into raw sugar. Each farm’s juice is sampled separately to determine its sugar content (CCS). The bagasse is recycled as fuel for the mill boiler furnaces.

  1. Heaters

The juice is passed through a series of heaters. Juice extracted from the crushing mills contains impurities which are removed by adding lime.

  1. Clarifiers

The lime neutralises acids and precipitates impurities that settle out in large, specially designed vessels, called clarifiers. The clear sugar juice is run off from the top of each clarifier. Muddy juice extracted from the bottom of the clarifiers is mixed with fine bagasse and then filtered, using cylindrical rotating vacuum filters to recover the sugar. The mud and bagasse mix is known as mill mud.

  1. Evaporators

The clear juice from the clarifiers is concentrated by boiling it under vacuum in a series of connected vessels, called evaporators. The concentrated juice is called syrup or liquor.

  1. Pans/crystallisers

The syrup, which is about 65-70% sugar, is further concentrated through boiling in a vacuum pan, where it is seeded with small sugar crystals in a process called crystallization. The sugar crystals are grown to the required size (about 1mm), the mixture of syrup and crystals is discharged from the pan.

  1. Centrifugals

Syrup is separated from the raw sugar crystals in centrifugals, which contain perforated baskets. They spin at high speed in a casing similar to a household washing machine. The dark syrup surrounding the crystals is thrown off and passes through the perforations. It is boiled again at the pans and more raw sugar crystals are recovered. This process is repeated until the amount of sugar obtained is too small to make further extractions economical. The syrup left over from the final centrifuging is called final molasses.

  1. Sugar dryer

The raw sugar from the centrifugals is dried by tumbling through a stream of air in a rotating drum.

  1. Sugar storage

The raw sugar is then transferred for short-term storage in bulk bins at the mills.

By-products

Molasses

Molasses is the thick, dark product which remains after as much sugar as possible has been removed. It is used as a valuable stockfeed. It is also fermented to produce ethanol, yeast, and monosodium glutamate. Significant quantities of molasses are exported each year through Australian Molasses Trading.

Bagasse

Bagasse is the fibre leftover after sugar cane is crushed to remove its juice. It is used as boiler fuel at all four Burdekin Sugar mills to produce steam, which is converted into electricity for the milling process.

Mill mud

Mill mud is the mud and dirt washed off the cane when it reaches the sugar mills. Rich in nutrients, mill mud improves soil fertility and is commonly used as fertiliser on cane farms and other applications.

That is what I have learned from the diorama.

Now what it doesn’t tell us – and why should it? – is that we consume way way too much sugar today. I understand that it’s a whole industry behind it and much more so. Yet, we don’t need that much sugar in our lives, in fact, we shouldn’t eat that much sugar. We are literally killing ourselves by eating the wrong food. We are heading to a (bitter)sweet death!

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