Cement Kilns



  • Grid reference: NZ51563452
  • x=451560
  • y=534520
  • 54°42'11"N; 1°12'0"W
  • Civil Parish: Throston, County Durham

Clinker manufacture operational: ~1863 to 2/6/1939

Approximate total clinker production: 1.96 million tonnes

Raw materials:

  • Limestone:
    • Thames chalk ballast
    • 1902-1919? Upper Chalk (Seaford Chalk Formation: 85-88 Ma) from owned quarry at Purfleet: 555700,178300 West Thurrock, Essex: 500 km by sea.
    • 1919?-1939 Carboniferous Limestone (Four Fathom Limestone Member: 326-331 Ma) from Barton Hill: 421700,508100 Barton, North Yorkshire: 55 km by rail.
  • Clay:
    • Tees Alluvium from Cowpen Bewley, County Durham 451200,525300
    • from around 1902 Boulder Clay from Saltholme, Cowpen Bewley, County Durham 449600,423200: 12 km by rail.


  • ~1865-1919 Otto Trechmann Ltd
  • 1919-1939 Warren Cement Works Ltd

Peter Otto Eduard Trechmann was born in Wilster, not far from Lägerdorf, in 1820, and set up at Seaham as a shipping agent. The Warren plant had previously been used for "Roman Cement" manufacture. Hart Warren, the dune-line stretching north-west from Hartlepool, had been used as a dump for chalk ballast by the Hartlepool docks, and Portland cement manufacture started shortly after Trechmann’s takeover. Initially there were five wet process bottle kilns; this was expanded to thirteen (390 t/week) by 1885. A set of five pairs of Dietzsch kilns and a set of ten chamber kilns were added in the late 1880s. All except five bottle kilns were removed. Trechmann, with his German contacts, was the first British manufacturer to use Dietzsch kilns. Capacity at this stage was Dietzsch 500, chamber 265 and bottle 150 t/week. The plant was one of a few in the area that experimented with the use of slag in the early 1900s. Around 1904-1905, two rotary kilns were installed, the bottle kilns were removed, and all the chamber kilns were decommissioned by 1906. The Dietzsch kilns gave 500 t/week, and the rotaries 400, giving Davis’ 1907 capacity of 900 t/week. Trechmann’s was primarily a shipping business from the outset, and this allowed it to continue moving chalk from the Thames after other manufacturers had given up. However, almost all its fleet was lost during WWI, and the shipping business was wound up in 1919. This is probably also the time when the Purfleet quarry was sold, and the plant was modified for grinding hard limestone. Capacity was said to be 1200 t/week eventually .

The plant was the last of those in the north-east dependent on remote raw materials, and its demise, although logically inevitable, was drawn-out and surrounded in mystery. Francis says that the cement company was sold to ICI in 1919. In the Oxford Dictionary of National Biography entry for Charles Taylor Trechmann (55, p 249), it is said that the family business was sold to ICI “about 1924”. Both these statements (presumably with a common origin) are suspect since ICI did not exist before December 1926. 1924 was the year in which shipment of anhydrite to the SA&N plant at Billingham began. The plant was run down during the depression and ceased production in 1939, although it remained in operating order in expectation of new finance. A parliamentary question was raised concerning its failure to obtain government assistance. However, Herdman (op cit) states that there was a fixed 99 years life for the plant stipulated in the original lease of May 1840. The company (Otto Trechmann Ltd ) was bought out by a consortium of Blue Circle, Tunnel and Rugby in mid-1939 and the plant was promptly decommissioned. Herdman says some of the machinery was sold to ICI. The site remained abandoned until 1948, when it was completely cleared, and the site remains mainly waste ground. The plant, being close to Hartlepool docks, had good road, rail and water transport facilities.

The plant had its own anhydrite mine, which operated from 1924 to 1930. Since it must have had a substantial output, employing as many as 190 underground workers, it must have sold most or all its product to SA&N and ICI. It shut down in 1930. Charles Taylor Trechmann (Otto’s grandson) was a prominent geologist. He drilled deep boreholes in the locality and wrote extensively on the geology of the Durham coast. The subsequent development of the anhydrite mine at Billingham (1927) was due largely to his work.

Please contact me with any relevant information or corrections. I am particularly interested in firmer dates and statistics.


A washmill was originally used, fed with chalk and clay from rail. With the use of hard limestone, the clay slurry was ground with limestone in tube mills.

Three rotary kilns were installed:

Kiln A1

Supplier: Fellner & Ziegler
Operated: ?11/1904 - 1915: 1918 - 1931
Process: Wet
Location: hot end 451534,534566: cold end 451526,534535: hot end enclosed.
Dimensions: metric 30.00 × 2.000
Rotation (viewed from firing end): clockwise
Slope: ?°
Speed: ?
Drive: ?
Kiln profile: 0×2000: 30000×2000: tyres at 2400, 13500, 25500: turning gear at 13750
Cooler: rotary, metric 16.20 × 1.450 beneath kiln
Cooler profile: 0×1300: 16200×1450: tyres at 1200, 13500: turning gear at 4000
Fuel: Coal
Coal Mill: indirect: ball mill common to A1 and A2
Typical Output: 1904-1915 29 t/d: 1918-1931 46 t/d
Typical Heat Consumption: 11.0 MJ/kg

Kiln A2

Operated: ?10/1905 - 1915: 1918 - 1936
Location: hot end 451539,534563: cold end 451530,534532: hot end enclosed.
Rotation (viewed from firing end): anticlockwise
Identical in all other respects to A1

Kiln A3

Supplier: Ernest Newell
Operated: 1914 - 1915: 1918 - 5/1939
Process: Wet
Location: hot end 451544,534558: cold end 451529,534521: unenclosed.
Dimensions: 120’0” × 7’4½” (metric 36.58 × 2.248)
Rotation (viewed from firing end): clockwise
Slope: ?°
Speed: ?
Drive: ?
Kiln profile: 0×2248: 36576×2248: tyres at 3429, 17145, 35433: turning gear at 18974.
Cooler: concentric rotary beneath kiln
Cooler profile:
Fuel: Coal
Coal Mill: ?
Typical Output: 68 t/d
Typical Heat Consumption: 7.8 MJ/kg

Sources: Cook, pp 103-104: Francis, pp 227-228: Jackson, pp 281, 300, 301: J. Herdman, The Warren Cement Works, Centre Circle, 2002 (Durham Record Office pamphlet B 14/6)

© Dylan Moore 2011: commenced 10/08/2011: last edit 11/07/2017.

Return to plant list

Old Maps

A detail plan of the plant has been partially completed, but further progress is prevented by lack of information on the layout of the earlier plant and later additions.

Approximate capacity: tonnes per year
Warren Capacity