THE GREAT SUGAR REFINERY AT BRISTOL - 1873.

It has lately happened that sugar in its various forms has attracted very general attention. The importation of sugar into the United Kingdom last year amounted to nearly sixteen million hundredweight, and of this amount fourteen millions and a half were entered for "home consumption." We may remark, moreover, that this represents about half a hundredweight a year for every individual in the population, so that, even reckoning a vast quantity consumed for making preserves and other articles of luxury and ordinary diet, a large quantity must be left for consumption in its natural or refined condition. We observe also that of the sugar destined for home use 5,224,470 cwt. came from British possessions, 3,091,275 cwt. from the Spanish West India Islands, 1,878,587 cwt. from Brazil; while 2,238,811 cwt. came from France and 34,816 cwt. from Germany, a large proportion of the latter two items being probably coarsely-prepared beet-root sugar of a low saccharine quality. It appears, indeed, from the returns that by far the largest quantity consisted of what is called raw sugar, and that a very considerable proportion of this must be converted into refined or loaf sugar, though doubtless the use of raw or moist sugar is still falsely regarded as economical among the poorer classes.

It is true that even some of the moist sugars undergo a process of refining, and that loaf or lump sugars of low quality are sold at a price so little above that of the raw sorts as to bring them within the reach of the million ; but in neither of these forms is actual purity attained, and in both moist and lump sugars the saccharine or sweetening quality is frequently small because of the intermixture of beet and other low-class sugars, which are in this way sold at the same price as cane sugar.

By the old process, which is still retained in some refineries, either bullocks' blood or "finings", made by mixing a solution of alum with lime-water, is used for forming a coagulation, which rises to the surface and takes with it the impurities of the sugar, in the shape of scum, to the top of the "blowing-up pan". But a more complete result can now be obtained by filtering through animal charcoal, and this plan is mostly adopted. The question is, how to obtain perfectly pure sugar, which shall have the largest amount of saccharine property and can yet be sold at a price which brings it into direct competition with the coarse, impure sugars known as "moist". This result has been attained by complete crystallisation after refining, and the process by which it is produced may be seen at the largest refinery in England - that of Messrs. Finzel and Sons, of Bristol.

The Counterslip factory, at Bristol, was established within the present century by the father of the present senior partner and the grandfather of the junior partners - the late Mr. Conrad Finzel, who by his application of centrifugal machinery to the completion of crystallised sugar, and by the adoption of various improvements in the earlier stages of manufacture, achieved a great commercial success and reputation, in obtaining a new and cheap form of the pure product.

The original building at the Counterslip shared the fate of many other sugar factories, and was burnt to the ground. Of the present great block, which covers nearly two acres, one portion was not completed till 1847, the other having been erected in 1859 ; so that the three tall shafts which are visible almost as soon as we have left the railway station, mark the progress of a business which has grown with marvellous rapidity, until the weekly production of its special manufacture has reached 1200 tons.

There is sufficient indication of its extent in the broad area between the factory and the warehouses - processions of drays and wagons bring boxes, bags, and tierces, which are conveyed on tramways to the lower part of the big building, to be converted into the brilliant colourless crystals, packages of which are coming out on another tramway in an almost endless train.

Arriving first at the sale-room and the sampling-room, where a surprising variety of raw sugars are inspected and purchased, we are conducted through the ordinary offices, and thence to the private room of the firm, on the first landing. We go up to the laboratory, a plain but very completely appointed apartment on an upper story, where sugars in every variety are tested, and afterwards experimentally submitted to the refining process. The apparatus here consists of vats, filtering cylinders, vacuum-pan, and centrifugal machine, by means of which an able practical chemist and analyst conducts in miniature the operations that are consummated on a gigantic scale in the adjacent building. It is worth noting, however, that even in this laboratory, as the experiments are intended to have a practical result, 10 cwt. of sugar can be carried through all the processes for converting it into crystals.

These processes, however, must be seen in the factory itself, and we will pass out of the commercial department and into the refinery, or rather into one of its departments on the first floor. Here casks, bags, and boxes of Demerara, Mauritius, and Havannah, together with baskets from Java, are disposed of with astonishing celerity by the men who receive them. Constantly as they come up, they are unhooped, ripped open, or staved in, and their contents are at once capsized through openings in the thick timber floor, beneath which lie the great boiling-pans, where the first operation of refining is effected by the reduction of the raw sugar to a brown viscid syrup, sufficiently fluid to be strained through coarse canvas bags, which are contained in a series of cisterns. This rough filtration removes from the sugar its coarser impurities, and it is allowed to pass from the bottoms of the bag-lined cisterns to a great reservoir, the magnitude as well as the contents of which enable us to contemplate it with a feeling like that of a fly peering over the edge of a dish of honey.

Presently, having safely surmounted the difficulties of a tortuous iron staircase, we are in a great, dim expanse of floors and beams, strange side-lights, and sudden shadows. This is, in fact, the floor where, by galleries and footways, we reach the mouths of a numerous series of deep filtering cylinders, each of which is filled with animal charcoal finely ground. Into these the brown, viscid syrup is pumped from the main tank or reservoir, and here the actual refining process may be said to be effected. So important is this second filtration, and, if properly conducted, so completely does it remove every particle of foreign impurity, that its results are very carefully watched. The operation of each separate cylinder is marked and recorded by means of copper pipes, one of which runs from the bottom of each, and terminates in a tap fixed over a long copper trough, so divided into compartments as to make it quite easy for an inspector to detect any imperfection in the syrup yielded by any one of the long series of filtering cisterns, and to trace it to its source.

The liquid syrup, or clarified fluid sugar, when it leaves these charcoal filters, is perfectly colourless and of intense sweetness, while its purity is so complete that crystallisation may be at once effected. A number of reservoirs receive it from the cylinders, and from these it is at once pumped up again into enormous vacuum pans, some of them capable of containing from 27 to 30 tons of sugar each ; while two of them - the largest in the world - will turn out respectively 400 and 500 tons a week.

It is in these pans that the sugar is crystallised, by evaporation of the moisture and concentration of the clarified syrup, and this is the process which requires the greatest attention. By the old process this concentration was effected by boiling the syrup in open pans, where, of course, the temperature was much greater, and all kinds of devices were employed for regulating the heat to an even degree. Seventy years ago, we are told, the Hon. Charles Edward Howard, starting from the ascertained principle that fluids will boil in a partial vacuum at a much lower temperature than in an open vessel, invented a closed copper pan or boiler, the middle of which was cylindrical, and the top and bottom spherical in form. This vessel had a double bottom, to the cavity of which steam was admitted, so that the contents of the pan could be raised to any required temperature, while a coil of copper pipe carrying steam through the body of the pan itself assisted the evaporation of the syrup. The bottom cavity contained steam at low pressure, the spiral coil being supplied with steam at high pressure, and consequently at great heat ; and from the centre of the crown or dome of the pan a bent tube and apparatus was connected with an air-pump, so that the pan could be almost entirely exhausted of air, while a valve served to admit small quantities of air in case of a too rapid exhaustion. With this contrivance and the air-pump at work the sugar could be boiled at a temperature of 130 deg. to 150 deg., while the exact heat could at any moment be ascertained by properly adjusted thermometers and immediately regulated.

All modern adaptations of vacuum-pans are founded on Howard's invention, and the gigantic vessels used at the Counterslip refinery are on the same principle, with the addition of certain improvements and modifications which serve to reduce the degree of heat at which boiling may be effected, and to secure facilities for frequently testing the progress of crystallisation. The operation may be seen going on in the most extraordinary manner through a round, thickly-glazed peep-hole in the side of the copper monster, within which the sugar bubbles and stirs into aggregated crystal forms, which ultimately fall to the bottom of the vessel in a moist, warm, grainy mass.

This granulated mass is allowed to fall into one or other of a long row of copper coolers in a floor beneath the evaporating pans, and thence, when its temperature is considerably diminished, is subjected to the process which first distinguished Messrs. Finzel's sugar from that of other manufacturers.

It is this process which perfects the sugar and reduces it to pure saccharine divested of superfluous moisture and any remaining syrup by submitting it to the action of the centrifugal machines, a large number of which occupy two separate floors of the refinery, and are unceasingly at work.

These machines are large cylinders of copper, set in a frame or bed, like so many enormous camp soup-kettles without lids, but with this difference, that each cylinder is made to revolve with great rapidity on a central axis, and that within the cylinder itself is a lining of wire gauze, between which and the outer pan some space is left.

To these centrifugal cylinders the cooled crystallised sugar is brought by means of a travelling trough running above them along the whole length of the room, and each machine as it receives its charge is set rapidly in motion, revolving with such velocity that every particle of moisture is flung off the whirling crystals, which come from this finishing operation hard, dry, and beautifully lustrous in appearance. So rapidly is this operation effected (the cylinders making many revolutions in a second), that a hundredweight and a half of sugar is completed by each machine in a minute and a half.

From each cylinder the charge of sugar is taken by an attendant workman, who receives it in a perambulator, which conveys it to a lower floor to become perfectly cool.

The process of refining may now be said to be complete ; but the mass of sugar has yet to be raised by means of lifts to the mixing-room, where a long detachment of workmen receive the products of the mechanical portion of the factory and deftly mingle it with wooden shovels. The mixing-room presents a very striking, and even a picturesque, appearance ; for it is a vast lofty hall, in which are elevated a number of high stages or galleries built of timber, and bound at the edges with iron. These stages mark off a great square space on the floor below, which itself has some distinguishing divisions, and into which the crystallised sugar is shot from the perambulators in which it is conveyed along the upper galleries. The cataract of white crystals pouring down from the iron-bound edges of this upper gallery to augment the heaps below, amidst which the white dresses of the men offer an opaque contrast, suggests a confused recollection of early reports of Cape diamonds and rock crystals. But perhaps by this time the strong saccharine influence of the atmosphere is inducing a somnolent condition, which is only partially dissipated by an introduction to the basement of the building, where in the filling-room a series of traps in the ceiling admit the mixed sugar from the floor above into shoots, and so it is poured into the tierces, bags, and packages in which it is sent out. Each filler in this lower room has his particular shoot, and when he requires a fresh supply of sugar he gives a sharp peal on a bell, which apprises the mixers that they must open the trap with another discharge.

The necessity for this careful mixing is to be explained by the fact that the crystallisation differs in its various stages, so that crystals of various sizes are turned out of the vacuum pans, and require to be mixed in order to secure a certain uniformity of quality. The filling-room is, of course, one of the busiest departments of the factory, and the rapidity with which the sugar is rammed down into the various packages with great iron pestles, and the deft dispatch which distinguishes the heading in of casks, the hooping of tierces, and the making up of big parcels, is enough to make the observer wink.

It should be noted that each tierce and hogshead is entirely lined with a peculiar kind of waterproof paper, which excludes both dust and moisture, and that small parcels of sugar are made up in bags perfectly lined with the same material.

Of course the supply of casks and tierces is in itself a very large business, and this is the work of a branch establishment - St. Paul's Cooperage - where, two or three streets off, above a hundred and fifty men are employed, under the direction of Mr. William Finzel, the youngest son of the senior partner. There is an atmosphere of sugar here also, from the number of casks and boxes which are sent to be utilised after they have been emptied of their contents ; but the saccharine flavour is almost superseded by the pervading sense of beech-wood, oak-wood, and ash, represented by piles and stacks of staves, by logs and trunks, which are to be reduced to heads and struts of casks by a great circular saw ; by stores and sheds where rushes, hoops, and old rope (for caulking purposes) are kept, and by the merry din of a hundred stalwart coopers, who seem bent on hammering each other into permanent deafness. The average consumption of timber in the cooperage is 450,000 ft. every week, so that we may regard the package department as a very considerable branch of the refinery - though a visit to the boiler-house on our return obliterates the figures of the cooperage from our estimate. About thirty steam-engines are at work night and day to supply the motive power of this great factory of sugar, and thirty-one boilers are required to supply the steam, not only for the engines, but for the processes of the refinery.

With regard to the quality of this sugar, the latest analysis of the crystals gives :

Moisture, which is no more than .059, representing by far the larger portion of the total of foreign matter, which altogether amounts no more than 1-1300th part of the gross weight - as near an approach as possible to absolute purity, and with the additional advantage claimed for this sugar, that its integrity of substance prevents it from absorbing moisture from the atmosphere and renders it most valuable for preserving or confectionery purposes, since it is not likely to ferment or to deteriorate, and does not waste material by the formation of large quantities of scum during boiling.

And what about the 700 workpeople employed in this great hive? It would be almost impossible to visit a factory nowadays without seeking to know something of the relative position of "employer and employed". In this respect it is not too much to say that these relations at the Counterslip are characterised by liberality and mutual confidence arising out of a very pleasant organisation, which appears to have been originated by "the Good Conrad Finzel" (for by that title the founder of the house is still known in Bristol), and is well carried out by his present representatives.

The hands here receive a higher rate of wages than is paid at any other refinery in the west of England, since it is essential to secure competent workmen to conduct the processes for obtaining this highly-crystallised sugar. But apart from this there are several beneficial provisions in connection with this industrial colony. There is a library and reading-room, and religious instruction and ministration by a duly qualified minister for the families of those who desire to embrace the privilege ; there are also numerous beneficent provisions for the old, the sick, and the disabled, the widow and the orphan.

The "benefit club", supported by the men themselves, has the firm amongst its best subscribers ; but the benefits established in connection with the factory itself are even of more importance, for they embrace provisions by which any man meeting with an accident serious enough to disable him receives half his wages if he has been more than seven years in the employ of the firm, and seven shillings a week if his services have been for a shorter period. Should the accident prove fatal and the man leave a widow, she receives five shillings a week for life. A large number of old and infirm workmen also receive superannuation pensions ; so that in the little territory of the Counterslip some of the social problems of the day come near solution.

from ... The Illustrated London News, 29 Nov 1873, p515.