Clinker manufacture operational: 11/1907-1932, 1936-1939, 1946-1963
Approximate total clinker production: 3.0 million tonnes. Prior to the formation of Crown & Quarry in 1907, the seven Frindsbury plants had made about 2.8 million tonnes.
The plant was the successor of the Frindsbury group of seven adjacent plants (from north to south, Phoenix, Globe, Bridge, Crown, Quarry, Beehive and Beaver). See also a general history of the Frindsbury cement plants. Their combined capacity (t/year) was as follows:
The site was cramped and short of raw materials as the chalk of the Frindsbury peninsula was rapidly removed, leaving existing settlements, and the parish church, precariously perched on chalk pinnacles. APCM having acquired the entire group therefore cut back and rationalized the operations of the site as “Crown and Quarry”, although it is symptomatic of the management paralysis of the combine at this time that the rationalization was delayed until 1907.
Of the seven plants, Phoenix and the already-closed Bridge and Globe plants were left derelict until the leases were sold in the late 1930s. By the amalgamation of the remaining Crown, Quarry, Beehive and Beaver plants, it had initially 88 chamber kilns with a capacity of 2555 t/week. The Crown kilns were removed around 1912, leaving 59 kilns with a capacity of 1714 t/week. This was for a projected rotary kiln which was shelved due to WWI. From this time on, the chamber kilns were used intermittently as make-up capacity. They were last used in 1925 when, to make room for the installation of the first rotary kiln, the Quarry chamber kilns were removed, leaving only the 34 kilns of Beehive and Beaver; these also were shut down and progressively removed. The rebulit plant was provided with extra clinker grinding capacity that could be fed directly by crane from barges, allowing the plant to grind clinker from the plants above the bridge - mainly Burham, and later Martin Earles. During WWII, the plant was requisitioned for fertiliser manufacture. The early plants’ site had no rail link, although the quarries were connected with standard gauge rail. In 1929, the quarry track was connected to the main line at Strood dock, but water transport remained predominant throughout the later life of the plant. The whole Frindsbury plants site has been completely redeveloped, the more recent plant area being occupied by the incongruously-named Laser Quay trading estate. The quarries have also mostly been built over, but the more northerly ones around the parish church are still waste land.
A washmill and screener mill located on the quay were used, milling chalk and clay together.
Two rotary kilns were installed:
Supplier: ex Magheramorne A2 (FLS) reassembled by Head Wrightson with a Vickers Armstrong Desiccator added
© Dylan Moore 2011: last edit 14/09/13.
Approximate capacity: tonnes per year
The bank of the river on Limehouse Reach was the site of the first Portland cement plant in the Medway Valley in 1851. At this point the river cuts through the uppermost levels of the Upper Chalk in an incised meander. A ridge of chalk runs NW-SE, and the river, in rounding the Frindsbury peninsula, runs hard against the chalk slope on the upstream (west) side, and forms an alluvial flood plain on the downstream (east) side. Thus, when I. C. Johnson decided to set up in business on his own, the location had a number of advantages:
Furthermore, a disused steam-powered oil mill already existed on the site, and Johnson took over the lease on this. In order to facilitate construction of the cement plant to his specifications, Johnson went into partnership with the prominent engineering contractor George Burge. The company was called Burge, Johnson & Co, and the plant was named the Crown Works. George Burge put his son (George junior) in charge of the cement operations, and when Johnson left in 1853, Burge junior was left in sole charge. George Burge Jr (1832-1911) concentrated on cement manufacture and on the development of new kilns, and became the key figure in the subsequent development of the site, constructing all seven cement plants. He also constructed the Falcon and Gillingham plants and rebuilt the Wouldham Court plant.
Operation of the Frindsbury plants was complicated by land ownership considerations. The southern part of the peninsula was (and still is) owned by the Rochester Bridge Trust, and the northern part was (and still is) owned by the Dean and Chapter of Rochester Cathedral. Both were inalienable feudal lands, and the landlords were due both ground rents and mineral extraction royalties. Johnson's original plant straddled the boundary of the two land lots. Rather than deal with multiple quarry operators, a single mineral extraction company was nominated, and all users were required to source their chalk from this. George Burge Jr went into partnership with wheeler-dealer William Tingey (1821-1907) to obtain the lease on most of the peninsula chalk land, and they formed the Rochester Chalk Company to work it. The chalk at Frindsbury was of limited extent and difficult to develop, and the company opened up more reliable chalk lands up-river at Wouldham. For the rest of the 19th century the operation of the cement plants was affected by strained relations with the chalk company.
George Burge Jr sold his Crown plant to William Tingey in 1868 and set up the Phoenix Portland Cement Co Ltd (in partnership with John McGowan) to operate the Phoenix plant on the site of a previous lime plant at the north end of the site. The Crown plant was from then on owned by William Tingey & Son until 1900, although Burge continued to design and construct its expanding manufacturing equipment. Both the Crown and Phoenix plants initially had wet process bottle kilns with slurry backs and separately-heated drying flats. In the 1870s, probably in co-operation with his mentor I. C. Johnson, Burge developed a chamber kiln design, and subsequently obtained a patent 1872. He formed a partnership with William Morgan and C. R. Cheffins to set up the Gillingham plant (trading as the Gillingham Portland Cement Co Ltd) and probably installed his first chamber kilns there. The partnership was subsequently joined by Frank Chapman – William Tingey’s son in law.
Burge probably installed his first Frindsbury chamber kilns at Crown in 1876. After this, the proven compactness and labour economy of chamber kilns prompted Burge to construct more plants. In 1880 he set up the Globe plant for J. C. Gostling & Co Ltd, who had previously set up and operated the London Portland plant at Northfleet. He also set up the Beehive plant which he operated himself as an experiment in his first use of a double-deck chamber kiln design similar to the Batchelor kiln. After the success of the latter, most of the kilns he installed were of this type, allowing many kilns to be crammed in to the restricted footprint of the Medway bank. The Phoenix plant was converted to chamber kiln operation in 1883.
The subsequent timeline of the Frindsbury site was as follows:
The Frindsbury plants in 1907, at their maximum development, and before Blue Circle began to dismantle them, showing locations of washmills (where known) and chamber kilns. The grid squares are 100 m. The land-lot boundaries are approximate.
There follows a list of all the chamber kilns installed at the Frindsbury site, based upon the best available information. This provides a large database of chamber kiln characteristics, but it should be borne in mind that, given that all the kilns were constructed by George Burge Jr, they are not necessarily representative of chamber kilns in general.
This section © Dylan Moore 2013: last edit 23/06/13.