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50-587: The Sanson Tramway in the Manawatū region of New Zealand operated from 1885 until 1945. Owned by the Manawatu County Council, it connected with the national railway network at Himatangi on the Foxton Branch . It was never part of the national network . After the construction of a tramway (later upgraded to a railway) linking Foxton and Palmerston North, settlers north of Foxton began efforts to have

100-445: A base for cattle-feed, industrial alcohol, yeast production and so on. Boiling in a vacuum pan used to be a batch process, but continuous pan boiling is inherently far more efficient. In the 1970s the first commercially successful continuous vacuum pans (CVPs) were developed. In the 1980s these first pans achieved a better uniform crystal size than that which some factories achieved with their batch process vacuum pans. The sugar from

150-470: A completely separate factory or at a back-end refinery which is attached to the raw sugar factory. A cane sugar mill can also produce sugar that is suitable for direct domestic or industrial consumption. This is called plantation white sugar or mill white sugar, see below. The overall quality of raw sugar that goes into the factory is dependent on agricultural practices and the cultivar used. Harvesting can be done by machines or by hand. If done by hand, it

200-525: A high sugar yield and quality. Before the actual extraction of cane juice starts, the cane has to be prepared. This can be done by rotating knives or shredders. There are two modern types of processes for extracting juice from cane: The products of the extraction phase are: In 2004 and 2005 the Enterprise Sugar mill in Louisiana had a traditional mill and a diffuser, which both processed cane from

250-469: A juice of poor clarity, which can be recycled for further purification. The evaporation process serves to concentrate the clarified juice. The most widely used evaporator is a multiple-effect evaporator of the Roberts type. The product of this step is syrup of 78 to 86% purity with a soluble solid content of 60-65°Brix and containing 3.5-4.5% invert sugars. The temperature, velocity and retention time in

300-519: A logistics centre and the Volkswagen factory. Sugarcane mill#Harvest and transport to the sugar factory The term is also used to refer to the equipment that crushes the sticks of sugar cane to extract the juice. There are a number of steps in producing raw sugar from cane: These processing steps will produce a brown or raw sugar. Raw sugar is generally sent to a sugar refinery to produce white sugar. This sugar refining can be done either at

350-448: A rail link built from to their settlements so they could easily access the port. In 1878 the Foxton and Sanson Railway Company was formed in order to build a line northwards from Himatangi (then named Carnarvon) to Sanson, and it envisaged that the line would become part of a trunk route from Wellington to the north. Before construction began legislation was passed that made it appealing for

400-548: A rural tramway as they had been on the nation's expanding network of railway lines before being displaced by more powerful and substantial engines. When Foxton locomotive depot closed and passenger services on the Foxton Branch were withdrawn in 1932, running to Foxton from the tramway ceased. The line received a boost just before World War II when it was required to service contractors at the Ohakea RNZAF Base , and during

450-502: A stationary engine, or pulled by small, light locomotives. Tramways can exist in many forms; sometimes simply tracks temporarily placed on the ground to transport materials around a factory, mine or quarry. Many use narrow-gauge railway technology, but because tramway infrastructure is not intended to support the weight of vehicles used on railways of wider track gauge , the infrastructure can be built using less substantial materials, enabling considerable cost savings. The term "tramway"

500-402: A three roller crusher, which together open most of the thin-walled cells. The juice is then removed from these opened cells by leaching. I.e. the sucrose from these opened cells dissolves in water. The diffusion process proper takes place on the 10-16% of sugar containing cells that have not been opened. First hot water is applied to kill the protoplasm of the cells. This makes that the walls of

550-424: Is added to serve as nuclei for sugar crystals, and more syrup is added as the water evaporates. The growth of crystals continues till the vacuum pan is full. The crystals and the mother liquor (molasses) now form a dense mass known as massecuite . The 'strike' (contents of the pan) is then discharged into a crystallizer. In the crystallizer, the crystallization process of the massecuite continues. The purpose of

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600-409: Is generally controlled by a central process control system, which directly controls most of the machines and components. Only for certain special machines such as the centrifuges in the sugar house decentralized PLCs are used. This also has to do with security for security reasons. Sugar mills date back to Arab Egypt in the 12th century. An artisanal version is the trapiche , later substituted by

650-409: Is normally preceded by burning the field. However, stalks from a burnt field more quickly loose sugar content while waiting to be processed. Cane is transported by truck, narrow-gauge railway , container or cart . On arrival the cane is sold based on weight or sugar content. There are several ways to unload the harvest. Overall, limiting the time between cutting and milling is essential for achieving

700-441: Is normally used. Sugarcane diffusion is the process of extracting the sucrose from the cane by osmosis and lixiviation also known as leaching . There are two types of diffusers. One relies on immerging the mat of bagasse in the juice by counterflow. The other relies on percolation of the juice through the mat of bagasse. At a chemical level, the first step is to open the cells. This is usually done by revolving cane-knives and

750-591: Is not used in North America, but is commonly used in the United Kingdom and elsewhere where British railway terminology and practices influenced management practices, terminologies and railway cultures, such as Australia , New Zealand , and those parts of Asia, Africa and South America that consulted with British engineers when undergoing modernization. In New Zealand, they are commonly known as " bush tramways " and are often not intended to be permanent. In Australia

800-407: Is the exception. There are multiple ways to use sulphitation for making plantation white sugar. In the purification stage of cold acid sulphitation, SO 2 is added to the mixed juice in order to lower the pH to 3.8-4.2. Lime is then added to increase the pH to 7.2-7.4. Next the juice is heated to 103-105°C before moving to the clarifier. In the clarifier the impurities settle, and the resulting

850-403: Is then again heated to 55°C and lime and CO 2 is added till a pH of 8.4-8.6 is reached. This is followed by a second pressure filtration. At the end of the evaporation step, Sulfur dioxide (SO 2 ) is added to lower the pH of the syrup to 7.0. In sugar factories, carbonation is not widely used, because it requires large quantities of lime and CO 2 , and sulphitation is cheaper. India

900-447: Is then allowed to flash to its saturation temperature: this process precipitates impurities, which get held up in calcium carbonate crystals. The flashed juice is then transferred to a clarification tank. In this clarification tank, the suspended solids are sedimented. The supernatant , known as clear juice is drawn off of the clarifier. The clarified juice is then sent to the evaporators. The settled solids can be filtered to produce

950-552: Is then dissolved and fed back to the syrup, while the C-sugar is dissolved or used as seed for the B-sugar. In storage, plantation white is more vulnerable than raw sugar. Sugar produced by carbonation is especially vulnerable to color change. Ash content also contributes to discoloration. In Brazil discoloration is countered by storing at a maximum temperature of 35-40°C and by producing sugar of 166 IU so lots of color can be lost before

1000-402: Is then filtered. The purification stage of hot acid sulphitation involves first heating the mixed juice to 70°C before lowering the pH to 3.8-4.2 by adding SO 2 . The process then runs like that of cold acid sulphitation. The purification stage of double liming consists of first heating the mixed juice to 70°C and adding lime till a pH of 7.2-7.4 is reached. SO 2 is then added to lower

1050-473: The Manawatu County Council to build the line as a tramway and thereby qualify for subsidies. Work started from the Foxton line at Himatangi in 1882, and the line opened to Rongotea Siding on 23 August 1884, followed by Sanson , south-west of Feilding , on 16 November 1885. In 1902, a short extension beyond Sanson was opened to the southern bank of the Rangitikei River , opposite Bulls . The Sanson Tramway

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1100-433: The addition of phosphoric acid; surface-active agents and phosphate, followed by heating and aeration of the syrup and addition of flocculant . The syrup is then moved to a special clarifier. The crystallization and centrifugation steps for plantation white might differ on account of the boiling system used. For plantation white the regular three-boiling system can be used. An alternative is to only ship A-Sugar. The B-sugar

1150-414: The cell becomes semipermeable . By osmosis, water or thinner juice can then enter the cell and replace heavier juice until an equilibrium is reached. In this phase sucrose penetrates the walls faster than non-sugar with higher molecular weight. This makes that the purity of the last extracted juice from diffusion is higher than that acquired by straight milling, even while diffusing extracts more sugar. In

1200-424: The centrifuges is dried and cooled and then stored. During bulk storage the quality of the raw sugar decreases because of a chemical reaction between amino acids and degraded invert sugars, known as the maillard reaction . The raw sugar can also be directly packed into bags for shipment. In many cane sugar producing countries the standard sugar product is generally known as plantation white sugar. In rich countries,

1250-415: The crystallizer for more than a day. The C-sugar from the centrifuge is mingled with syrup and used as massecuite seed, and so returns to the start of the process. The molasses resulting from this centrifuge step are called final molasses, or blackstrap. It is a heavy viscous material containing about one-third sucrose, one-fifth reducing sugars, and the remainder ash, organic non-sugars and water. It serves as

1300-445: The crystallizer is to reduce loss of sucrose by it remaining in the mother liquor / molasses, in particular with low-grade massecuites. The crystallizer works by cooling the massecuite. This decreases solubility and again increases saturation, forcing crystallization to continue. Crystallizers are cylindrical or U-shaped vessels equipped with low-speed stirring elements. They are often connected in series for continues operation. Cooling

1350-401: The diffuser and this dilute juice is allowed to percolate through the bed of cane. At this point the concentration of sucrose in the cane is higher than the concentration of sucrose in the dilute juice just mentioned and so sucrose diffuses from the cane to the juice; this now slightly richer juice is pumped back up the diffuser and the process is repeated, typically, 12 to 15 times (compared with

1400-452: The evaporator are regulated to prevent sucrose inversion , or decomposition of sucrose in glucose and fructose. Another concern is scale formation on the heating surface of the evaporator. The application of a magnetic flow can help to prevent scaling. Crystallization is done with a single-effect vacuum boiling pan and a crystallizer. In the vacuum pan, the syrup is evaporated until it gets supersaturated with sugar. At this point seed grain

1450-553: The first stage, A-sugar, is stored. The molasses from the A-centrifugation, A-molasses, are fed to the B vacuum pan. This results in B-sugar and B-molasses. A mix of A-sugar and B-sugar forms the commercial product of the factory. The B-molasses are of a much lower purity. They are boiled again in the C-pan. While the A and B stage do not always use a crystallizer, it is essential for this low-grade massecuite. The massecuite remains in

1500-532: The four to six times for the milling process) The mixed juice has a pH of about 4.0 to 4.5 which is quite acidic. During purification, calcium hydroxide, also known as milk of lime or limewater, is added to the cane juice to adjust its pH to about 7 or 8. This can be done while the juice is still cold (cold liming) or after it has been heated to about 104°C (hot liming). It can also be done in phases (fractional liming). The lime helps to prevent sucrose's decay into glucose and fructose. The superheated limed juice

1550-567: The ground they were less likely to be blocked by debris, but they obstructed other traffic, and the wagons could not be used beyond the limits of the rails – whereas plateways had the advantage that trucks with unflanged wheels could be wheeled freely on wharves and in factories. Edge rails were the forerunners of the modern railway track. These early lines were built to transport minerals from quarries and mines to canal wharves. From about 1830, more extensive trunk railways appeared, becoming faster, heavier and more sophisticated and, for safety reasons,

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1600-425: The low standard of 230 IU is reached. Some cane sugar mills have so-called back-end refineries. In back-end refineries, raw sugar produced in the mill is converted to refined sugar with a higher purity for local consumption, export, or bottling companies. Wastage is used for heat generation in the sugar mills. The remaining fibrous solids from the juice extraction phase, called bagasse , are burned for fuel in

1650-470: The massecuite increases viscosity . At the optimum temperature for crystallization, the massecuite is too viscous for the centrifuge to properly separate the crystals from the molasses. However, as the mother liquor of the massecuite is still supersaturated at this point, the viscosity can be reduced without re-solution of the crystals. This can be done by bringing it to a state of saturation by heating or adding water. The sugar centrifuge serves to separate

1700-430: The massecuite into sugar crystals and mother liquor / molasses. These centrifuges consist of a cylindrical basket suspended on a spindle. The perforated sides are lined with wire cloth , inside of which are metal sheets containing 400-600 perforations per square inch. The basket revolves at 1000-1800 rpm. While the mother liquor, molasses passes through the holes in the centrifuge, the sugar crystals are retained. After

1750-655: The mill's steam boilers. These boilers produce high-pressure steam, which is passed through a turbine to generate electrical energy ( cogeneration ). The exhaust steam from the turbine is passed through the multiple effect evaporator station and used to heat vacuum pans in the crystallization stage as well as for other heating purposes in the sugar mill. Bagasse makes a sugar mill more than energy self-sufficient; surplus bagasse goes in animal feed, in paper manufacture, or to generate electricity for sale. As in many other industries factory automation has been promoted heavily in sugar refineries in recent decades. The production process

1800-401: The milling extraction efficiency, imbibition water is added at each mill. Hot water is poured over the cane just before it enters the last mill in the milling train and is recirculated up to reach the first mill. The juice squeezed from this cane is low in sugar concentration and is pumped to the preceding mill and poured onto the cane just before it enters the rollers, the juice from this mill is

1850-448: The pH to 5.4-5.6. Now a second portion of lime is added to again reach a pH of 7.2-7.4. Following this, the juice is heated to 103-105°C before moving to the clarifier. The evaporation step for plantation white is the same as that for raw sugar. At the end Sulfur dioxide (SO 2 ) is added to lower the pH of the syrup from 6.5 to 5.5. After evaporation, an extra clarification process can be inserted. Basic steps of this sub-process are:

1900-403: The percolation system process, shredded cane is introduced into the diffuser at the feed end; hot water is poured over the shredded cane just before the discharge end of the diffuser. The hot water percolates through the bed of cane and removes sucrose from the cane. This dilute juice is then collected in a compartment under the bed of cane and is pumped to a point a little closer to the feed end of

1950-466: The public highway, sharing with other road users. Initially horse-drawn, they were developed to use electric power from an overhead line . A development of the tramway in the United Kingdom was the trolleybus , which dispensed with tracks but drew electricity from overhead wires . Between 2001 and 2020, two trams built to carry automotive parts (the " CarGoTram ") operated in Dresden , Germany between

2000-462: The purification, evaporation, and storage steps. In the purification step, the objective of carbonation is to separate non-sugar contents such as colloids and insoluble particles as well as colored material. If carbonation is used, the mixed juice is heated to 55°C and lime is added till a pH of 10.5-11 is reached. Next, Carbon dioxide (CO 2 ) is added, and the juice is pushed through pressure filters. This results in calcium carbonate mud. The juice

2050-512: The requirements placed on them by Parliament became more and more stringent. See rail tracks . These restrictions were excessive for the small mineral lines and it became possible in the United Kingdom for them to be categorised as light railways subject to certain provisos laid down by the Light Railways Act 1896 . Meanwhile, in the United Kingdom the term tramway became the term for passenger vehicles (a tram ) that ran on tracks in

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2100-417: The same area. Weekly raw juice samples were taken and analyzed. These were found to be very similar, despite the diffuser achieving a higher extraction. Juice extraction by milling is the process of squeezing the juice from the cane under a set of mills using high pressure between heavy iron rollers. Those mills can have from 3 up to 6 rolls; every set of mills is called a tandem mill or mill train. To improve

2150-412: The same way pumped back up the milling train. Mixed juice (that is to say cane juice mixed with the water introduced at the last mill) is withdrawn from the first and second mills and is sent for further processing. Milling trains typically have four, five or six mills in the tandem. To improve the milling extraction performance before the cane reaches the first mill, knife and shredder preparation equipment

2200-503: The shaft of a wheelbarrow—in turn from Low German traam , meaning a beam. The tracks themselves were sometimes known as gangways , dating from before the 12th century, being usually simply planks laid upon the ground literally "going road". In south Wales and Somerset the term "dramway" is also used, with vehicles being called drams. An alternative term, " wagonway " (and wainway or waggonway), originally consisted of horses, equipment and tracks used for hauling wagons. Usually

2250-542: The standard sugar product for direct consumption or industrial use is white sugar . In Codex White A quality, white sugar has a minimum polarization of 99.7% and an ICUMSA color of 60 IU. Plantation white might have a polarization of e.g. 99.4-99.7% and a color between 80 and 250 IU. Plantation white sugar is produced by making changes to some of the stages mentioned above. There are two ways to make plantation white sugar, carbonation and sulphitation. To make plantation white sugar by carbonation requires changes to

2300-427: The sugar is purged, it is cut down, making the centrifuge ready for the next badge. It is quite common for sugar to result from repeatedly undergoing the crystallization and centrifugation steps. This depends on the boiling system The most common boiling scheme is the three-boiling system. This method boils the sugar liquors in three crystallization/centrifugation stages, called A-, B- and C-. The sugar resulting from

2350-516: The term was widely used in connection with logging, no longer extant. Today in the state of Queensland , however, there remain several thousand kilometres of sugar-cane tramways . Passengers do not generally travel aboard tramways, although employees sometimes use them, either officially or unofficially. The term was originally applied to wagons running on primitive tracks in mediaeval Great Britain and Europe . The name seems to date from about 1517 and to be derived from an English dialect word for

2400-578: The war petrol restrictions helped to generate traffic. These restrictions ended with the coming of peace and post-war traffic on the line was too insignificant to justify its continued existence. It closed on 29 November 1945. 40°23′28″S 175°19′00″E  /  40.391°S 175.3166°E  / -40.391; 175.3166 Tramway (industrial) Tramways are lightly laid industrial railways , often not intended to be permanent. Originally, rolling stock could be pushed by humans, pulled by animals (especially horses and mules), cable-hauled by

2450-424: The wheels would be guided along grooves. In time, to combat wear, the timber would be reinforced with an iron strip covering. This developed to use L-shaped steel plates, the track then being known as a plateway . An alternative appeared in 1789, the so-called " edge-rail ", which allowed wagons to be guided by having the wheels flanged instead of running, flangeless, in grooves. Since these rails were raised above

2500-444: Was initially operated by the steam tram Hibernia from Wellington. It was not an adequate source of motive power, and a former Foxton locomotive from the days when the Foxton Branch was a tramway commenced work on the line by the time it was opened to Sanson. As traffic became more substantial, old locomotives were acquired from New Zealand Railways to run on the tramway. As these locomotives were very light, they were just at home on

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