Clinker manufacture operational: 1883-1932
Approximate total clinker production: 1.76 million tonnes
The plant was built to the north of the pre-existing lime and brick plant, on the site of the worked-out brickfield. The 1886 Engineer article implies that Portland cement manufacture had been subject to “costly and fruitless attempts” at the site before the plant described was launched. A previous plant called the "Hydraulic Lime and Cement Works" was put up for sale in October 1875. This had two 25-ton wet process bottle kilns along with three wash backs and drying flats, evidently using chalk marl alone. Evidently only hydraulic lime had been produced. When the new plant started, chalk and gault clay were used, the clay being already available from the much more substantial brickworks next door. The plant as first designed exemplifies the great simplicity and compactness of the “off-the-peg” cement plant of the 1880s. Read the Engineer article.. The plant started up with a set of six Johnson chamber kilns, capacity 120 t/week. In 1887 four locally-designed double-deck chamber kilns were installed, giving 100 t/week. Installed in 1888 was one of the second-generation Ransome rotary kilns which, like the others, failed to operate successfully, although Stokes used it to pilot his own developments in the 1890s. Seven more chamber kilns (210 t/week) were added in 1891. A further block of six (190 t/week) and four Schneider kilns consuming excess slurry dryings (320 t/week) were installed around 1900. This made the total capacity 940 t/week. It became one of only two plants (the other being Vectis) outside the Thames/Medway area comprising APCM in 1900. The installation of the rotary kilns involved the removal of the first block of chamber kilns in 1903. The remaining static kilns continued in commission, although only intermittently used: they were last operated in 1926. All transportation was by road and the Great Northern Railway. Although the raw materials were excellent and the site was strategically good, negotiations to extend the land southward failed and the reserves of high carbonate chalk were insufficient to make an upgrade worth while, so the plant closed with the 1932 downturn. Most of the site is long cleared, and is now partly occupied by a readymix plant, but the second chamber kiln block still remains. Some foundations are still visible on the unoccupied ground towards the railway. The quarries are flooded.
Three rotary kilns were installed:
Supplier: “Pollitt and Wigzell”. This may just be a contractor. They made steam engines. The kilns were identical to those at Swanscombe and so were Fellner & Ziegler (considerably modified).
Rotation (viewed from firing end): clockwise
Cooler: rotary 53’0”× 4’10½” (metric 16.15 × 1.486) below firing floor.
Location: hot end 518981,235104: cold end 519022,235103: totally enclosed.
Read the Engineer article.
© Dylan Moore 2011: commenced 12/03/2011: last edit 26/02/2017.
Approximate capacity: tonnes per year
The Ransome kiln as modified by Stokes. Picture: Blue Circle archive. The photograph was taken in the 20th century long after it was abandoned and was modified for clarity. The hood and cooler below the kiln are gone. Behind the end wall was the slurry preheater.