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British Standard Portland Cement Company
New cement works were set up by E J and W Goldsmith, barge owners, at Motney Hill, Rainham in 1912. The firm was afraid of losing their share of the cement trade on the Thames after the British Portland Cement Manufacturers merger in 1911. The works were acquired in 1927 by the Horne Group who sold cement under the Red Triangle trade mark. The Horne Group modernised the works "at considerable expense".
A cement price war broke out in 1928 which only ended in November 1928 when the Horne Group and other independent producers joined the 'Cement Manufacturers Association'. The Horne Group then failed due to lack of finance after the price war, bad timing of investment in the industry just before the Depression, and possible poor management leading to inefficiency. The Horne Group was liquidated in 1931, with the Rainham works falling into the hands of Associated Portland Cement Manufacturers and closing soon after.
Little trace remains of the cement works or the adjacent dock. The vertical dock walls have been re-profiled by Medway Council, and the walls of dock side store houses leveled. The works site is now part of the nature reserve and has been reclaimed by scrub and bramble. Any buildings have been leveled, but it was possible a few years ago to trace the footprint of the silos and kiln bases.
The washmills in the quarry have survived to above ground level, and may be substantially interpreted. These are being excavated by the Friends of Berengrave, and more details of progress so far may be found at their website: www.friendsofberengrave.btik.com
The washmills appear to have been constructed in two phases.
The first phase in 1912 consisted of two circular washmills constructed in local stock bricks, an adjacent brick built boiler and engine house, and a further slurry pit from which the chalk slurry would have been pumped to the works.
Chalk would have been brought by the tramway to the washmills from the chalk face, and the normal practice was to put the chalk through a crusher before it was tipped into the first mill. There are some concrete bases to the east of the mills (marked on the plan as M and N) which may have been the site of the crushers. The washmills worked in tandem, the chalk being tipped into the first, where the chalk was broken down into smaller particles by an autogenous process, i.e. stirred around by the rotor arms and harrows and breaking up through friction between chalk particles. Smaller particles passed through a filter at the side of the mill [on the north west of the southern mill], from which the slurry is fed to the second mill where the process is repeated with a smaller gauge filter [west side of mill]. From here the slurry, which would contain fairly coarse particles would be pumped to a collecting pit, EO on the plan, for pumping, probably with a conventional three throw pump via a 6 inch diameter caste iron pipe, to the cement works. EO was equipped with an agitator to keep the slurry in suspension.
The engine house would, almost certainly before 1914, have been equipped with a coal fired boiler and a steam engine, of which there was still a wide range being manufactured and installed in cement works. It is most probable that there was a shaft drive between the engine and the washmills, where the substantial girder remains indicate the height of the rotor heads, gearing and shafts
The second phase of construction took place with the modernisation of 1927, with the distinctive use of concrete for all flooring and mounting blocks. The important point to consider is what was the function of any modification at the washmills. There would appear to be only one answer which would fit and accord with the layout on the ground. This was to further process the chalk slurry by grinding it to the fineness required for the final feed mix.
Feature EB would be the mounting for an oil engine. By 1927 diesel engines were commonly in use in cement works. Something like a Blackstone industrial engine would have served. This engine could have driven a shaft mounted on features EC, EG, EJ and EP. What the shaft would in turn drive via belts would be four machines each mounted on a pair of mounts, features B1 to B8. The equipment mounted would be vertical ball mills, the most likely manufacturers being
either F. L. Smidth of Copenhagen or Krupp of Germany, both of whom made
mills with a round base.
This leaves the question of the steel [iron?] tray. The obvious answer to this is that it was a sieve through the slurry ground to the required fineness would pass. Particles which would not pass through the mesh could be recycled through the ball mills. The fine slurry would then pass to the collecting pit to be pumped to the works. The sieve mechanism would most likely have been fabricated locally, e.g. by the works repair and maintenance department to meet the specific need. Both the ball mills and the sieve/filter would have required extra water, which probably accounts for the tank marked to the west of the washmills on the 4th edition Ordnance Survey. At least one set of pumps would have been needed near the feature ER
Given the lack of documentary evidence about the British Standard works, and the degree to which the works were dismantled and subsequently demolished, it is
difficult to be precise. We do not know a great deal about Goldsmiths' works, except that it had at least one rotary kiln using the wet process [which used a great deal of coal in drying the slurry in the first third of the kiln]. If as is suggested there was a ball mill to the east of the works, they might have been using the dry process in the second kiln. The only good photographs of the works appear to have been taken by Aerofilms in 1930 when all modifications were complete.
Jim Preston
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