Sugar beet is a temperate climate crop which is grown successfully in virtually all areas of the world with latitudes in excess of 30° where winters are not excessively harsh. The agricultural cost of producing beet sugar is significantly more than the equivalent cost of cane sugar, so efficiency of production is a high priority.
SKIL has been involved in beet agriculture since 1988 and has worked for major companies as well as small farmers.
Sugar beet is a useful crop for farmers, particularly when incorporated into a rotation scheme. In a good climate they can expect to achieve at least 60 tons/ha when the price they receive justifies the resources required to obtain such yields.
A sugar beet factory can only be operated efficiently if the quality of the beet received is suitable for processing. Cultivation techniques and material inputs must therefore be adapted to the climate and soil types of the region:
Not all land is suitable for growing beet so initial investigations are required to determine suitability and any remedial measures that may be required. Once the land is selected, and at every subsequent sowing, correct preparation is essential to ensure maximum germination takes place. A fine tilth with little stone content is needed to achieve this.
The use of the most effective variety or varieties of beet for the location is pivotal to the success of the crop. It is therefore essential to establish this with practical field trials and, in parallel, to optimise the chemical incorporation within the pelletising material coating the seeds.
Maximum yields can only be obtained when the spacing between rows and seeds within the rows has also been optimised. This sometimes means that existing drilling machines have to be replaced with more modern, high efficiency units.
Fertilisers of the correct type must be applied at the right rate throughout the crop if good yields are to be obtained. Similarly it is necessary to apply appropriate chemicals in order to control airborne and soil borne pests and diseases. Practical trials and experience are needed to determine the correct application procedures.
Harvesting has to be a co-operative exercise undertaken in collaboration with the factory if excessive sugar loss is to be avoided. Good harvest planning is essential.
The factory requires the beet to be delivered in good condition and as free as possible from soil and green material. Deliveries may be rejected in extreme circumstances. Harvesting machines must therefore be efficient, minimising breakages and giving a good separation of the soil and trash. They also have to be compatible with the seed drilling patterns.
Once the beet has been harvested there is a small but steady loss of sugar, exacerbated by poor storage conditions. It is therefore important that sugar losses during on-farm storage are minimised and the agreed delivery schedule to the factory is closely followed.
STAFF DEVELOPMENT AND TRAINING
The development of staff through parallel working is central to SKIL's philosophy but this needs supplementing with training programmes. This should be targeted for several levels of staff and might include the creation of a training centre and visits out of country. We consider the compilation of operating manuals as an integral part of training as well as being essential for good management.
SKIL is able to assist in every sector of beet agriculture and can provide personnel with practical experience of all aspects of beet cultivation whilst understanding factory quality requirements.
The efficient operation of a beet factory depends on full attention being given to every detail from beet delivery to final despatch. SKIL is able to provide personnel with practical experience in all aspects of factory management and operation:
The above disciplines can be applied equally effectively to both new and refurbishment projects.
Although beet is physically different from its tropical counter-part, sugar cane, the factory processes are surprisingly similar. Two major differences are the lower juice colour levels with beet - which allows direct production of white sugar - and a cane factory's self-sufficiency in fuel.
Each beet factory is unique, with its own set of process problems to solve and with a particular market to satisfy. Each aspect of the process therefore needs to be considered:
Reception of beet directly affects factory economics because most beet growing is outside of the factory's control. Sophisticated sampling and analysis systems have been developed to determine the sugar and soil contents in each load so that accurate payment methods are applied and poor quality loads rejected.
Storage of beet at the factory will depend on climatic conditions but can require several weeks' supply where harvesting disruptions occur. Good storage and effective delivery scheduling is therefore imperative to the avoidance of sugar loss.
Extraction starts with washing before the beets are cut into chevron shaped slices and introduced to the diffuser. Diffusion is achieved with water at about 70 °C in a counter-current process and strict temperature control and hygiene is required in order to achieve efficient extraction.
Purification of diffusion juice is simplified by the relatively low colour levels. It is normally achieved using carbonatation with the addition of appropriate chemicals to minimise fouling of the subsequent concentration steps.
Crystallisation follows evaporation to a syrup. Because beet factories are not self-sufficient in fuel the evaporation is more optimised for steam efficiency than a cane factory. It is normal to adopt a three boiling pan system.
Curing, Drying and Storage are all critical to the process because the sugar is produced as the finished product. Centrifugation must therefore be very efficient, drying involves subsequent conditioning and storage must be to the highest quality if the products, usually produced in a relatively short campaign, are to remain market ready throughout the year. If necessary the product can also be screened.
Packaging is a topic in its own right: a typical factory will be capable of producing a range of sugars from icing through cubes to liquid products and a range of packages from 8 gm sachets to bulk road/rail tankers. A direct and thorough knowledge of the market requirements, including modern packaging arrangements, is critical to success.
Factory profitability often relies on the efficient utilisation of the molasses and animal feed co-products. The spent beet fibre can be processed into a variety of both wet and dry animal feed products. The molasses can either be sold on its own, used internally for alcohol production or blended with the fibre to make an enhanced feed product. The importance of the feed products to the factory is such that uniform, high quality products must be produced at all times.
Our specialists can help you investigate all aspects of the industry in order to: