Concentrated expertise for a natural product
Green leaf threshing and the Primary are the start of a long journey. They are the first steps in the manufacturing process for cigarettes. Here, the raw tobacco passes through a number of stages to prepare it for use in the cigarette makers and ensure the whole process runs smoothly. Hauni’s subsidiary Garbuio is the global market leader in the development and manufacture of machinery and equipment for the Primary – supervising every step of the process and with a strong focus on quality.
The leaves have spent two years packed tightly together, separation is a delicate process. In the first step, the slicer cuts the raw tobacco bales into smaller slices. This prepares them for the next stage – tobacco conditioning.
Loosening and Conditioning
Supple and full of flavor
Tobacco conditioning and casing lay the foundations for a consistently high level of cigarette quality and ensure that downstream production processes run like clockwork. In the conditioning cylinder, the dry raw tobacco is loosened using water and steam which make it supple and increase the moisture content from 10 to 21 percent. This opens the pores of the individual tobacco leaves. They are ready for the next step.
The search for hidden particles
They may be tiny – but the smallest particles of non-tobacco related material can spoil the appearance and taste of a cigarette. A series of systems now inspect, detect, and remove unwanted material from the tobacco. These include magnets, screen belt conveyors, separators, metal detectors, and sophisticated optical detection systems. They ensure that only the tobacco remains.
Quality at its finest
Smells and tastes good
At this stage of the process, the leaves are sprayed with natural flavors in the casing cylinder. Here, the casing – and water contained in the casing – are sprayed onto the pre-warmed tobacco. It is important that warm casing is always applied to warm tobacco as this enables it to penetrate the pores in the leaf surface and enter the leaf more easily. The casing is a sugary liquid containing a variety of flavorings, e.g. glycerine and extracts of liquorice, chocolate, plums and figs.
Flat as a flounder
Tobacco leaves also contain stems. These are low in nicotine and sugar and thus in great demand for use in light, low-nicotine cigarettes. They have high filling power and are therefore indispensable in cigarette production. When the stems are flattened, the structure of the expanded fibres can be enhanced. In other words, the cigarette makers can process the stems more effectively and the quality of the cigarette also improves.
Once the tobacco leaves have been mixed to perfection, they go under the knife. The cutting tools must always be kept clean and extremely sharp because this has a significant impact on the quality of the final blend. But perfectly honed blades also increase precision and produce less dust. Tobacco cutters which automatically sharpen the knives according to their level of wear are a vital part of the product portfolio. They can process up to 12 tonnes of fine cut tobacco leaf and three tonnes of leaf stem per hour.
May we expand a little?
The tobacco is now rapidly heated to a temperature above the boiling point of water. Steam condenses on the tobacco, forcing up its temperature. The rapid temperature rise causes the water in the tobacco cells to expand. This increases the volume of the tobacco and gives it higher filling power. At the same time, it raises the moisture content from 21 percent to approx. 25 percent. The tobacco now passes into the dryer.
Immediately after being expanded, the tobacco is dried in a jet of steam heated to 300°C in a low-oxygen environment. This fast process dries the tobacco gently and fully preserves the cell expansion generated in the previous step. The moisture content drops from 25 to 13 percent.
Cooling prevents collapse
After drying, the tobacco is cooled. Why is that important? Firstly, because rapid cooling helps to stabilize the filling power gains achieved in the dryer. Secondly, because the dried tobacco must be cold when it enters the flavor cylinder. This is the only way to ensure there is no uncontrolled loss of aroma.
A final touch of flavor
The final step of tobacco processing. Flavorings are evenly sprayed onto the cut tobacco. They create the unmistakable scent of a freshly opened packet of cigarettes and give the cut filling material its characteristic flavor. The product is gently mixed during processing.
Optimum product solutions
In the right place at the right time
Hand over the tobacco
Before the next stage can begin, the tobacco has to be unpacked. The tobacco leaves are generally shipped to cigarette factories in 200 kg cartons or bales. So the first job is to remove the packaging. The unpacking station is fast, reliable, and flexible. It is capable of unpacking up to 48 cartons per hour – that’s around 12,000 kg of tobacco. The machine requires extremely little maintenance and can easily be converted for different carton designs.
Always stay flexible
Filling stations are vital for achieving maximum flexibility in the scheduling of cigarette production. Here, containers and cartons are carefully filled with cut tobacco. Tobacco can then be removed from them for production as required. These filling stations feature mobile tippers, gantry robots and other equipment. A storage area and fully automated logistics systems are also included.
The perfect feed
An abundance of tobacco – the blends are ready for processing. A variety of tobacco feed plants ensure a reliable supply of tobacco to the cigarette makers. These are directly connected to the Secondary. Tobacco is pneumatically transported through long pipelines from the feeder to the maker. The plants guarantee a smooth and gentle feed. The transport capacity and air speed can be precisely and automatically adjusted and controlled.
A smooth journey
From unpacking to sorting. From sorting to separating. From separating to moistening. From moistening to mixing. From mixing to cutting. From cutting to drying. From drying to cooling. From cooling to mixing. From mixing to the warehouse. Everything must run like clockwork. It involves an extraordinary range of conveyors – conveyor belts, flat conveyors, Troughed belt conveyor, heavy duty conveyor belts, vibratory conveyors, screening conveyors, and movable conveyors.
Billions of cigarettes – all with the same tobacco quality and high level of consistency. That takes a lot of work. The tobacco mass flow therefore requires precise monitoring and metering in the Primary. This is the task of weigh belts.
Efficient logistics systems
Storage and blending
Careful blending of the tobacco is essential. This is the only way to create homogeneous and consistent blends, which ultimately decide the quality of a cigarette and give them their unmistakable taste. Blending plants create the perfect tobacco blends. Multitalented machines have been developed for this process. They not only blend the tobacco but can also be used as storage silos and buffers.
This step removes larger particles, such as leaf stems, from the production flow. It increases the overall efficiency of the removal of unwanted stems from the cut tobacco. Fewer particles also mean fewer irregularities in formation of the tobacco rod during the cigarette manufacturing process. And fewer embers falling from the cigarette during smoking.
The preparation and finishing of tobacco is, to say the least, a dusty job. Dust extraction systems are required at various stations in the Primary. We support our customers with effective air-flow dust filters and cyclones. Air-flow dust filters separate the dust while cyclones remove solid bodies from the air. Both are then collected and, if necessary, re-used. From the removal of the packaging to the tobacco transport – we guarantee clean air in the Primary.
Tailored automation strategies
Hauni automates machines, lines and entire primary plants. With the best hardware and software components the market has to offer. Our teams keep an eye on new trends and liaise closely with customers and suppliers. Based on this information, our engineers then develop the best automation strategies available.
Machines & plants