• Grid reference:
    • ITM 679477,875116
    • old style H7957075142
  • 54°37'5"N; 6°46'5"W
  • Knockaconny, County Tyrone : the limestone quarry extends into Ballysudden and Galanagh townlands.

Clinker manufacture operational: 27/8/1968 to date

Approximate total clinker production to 2015: 17.4 million tonnes (24th)

Raw materials:


This was Ireland’s fourth rotary kiln plant, and the first with an efficient kiln. The kiln became the most successful of five of the same design in this study (the others being at Weardale, Dunbar and South Ferriby), and its efficiency and output were such that no serious consideration could be given to a change of process. It is thus one of only three Lepol kilns remaining. The kiln was briefly the largest in capacity until overtaken in 1970 by the Hope and Northfleet kilns, and it remains the longest-operating kiln.

The rawmills are distant from the kilns and could not use waste heat from the kiln system for raw material drying. They are heated with fuel oil, with typical heat usage ✄ MJ/kg.

The plant’s location is sufficiently close to Belfast (60 km) and Derry (50 km) to assure a good market although only road transport is available.

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

Note: technical information on currently operational plants is ✄withheld in the public version of the site at present unless already published.


One 1350 kW Aerofall mill for coarse grinding and one Polysius 900 kW double-rotator mill for separator rejects regrind(1).

One rotary kiln was installed:

Kiln A1

Supplier: Polysius
Operated: 27/8/1968 to date
Process: Semi-dry: Lepol 27.7×3.91 m grate(1): details✄

  • hot end: ITM 679487,875145 {old style 279580,375170}
  • cold end: ITM 679467,875108 {old style 279560,375113}: the kiln is entirely enclosed.

Dimensions: Metric 60.39 × 3.918BC / 4.351D(1)
Rotation (viewed from firing end): anti-clockwise(3)
Slope: 3.5% (2.006°)(3)
Speed: 1.1 rpm(3)
Drive: 134 kW(3)
Kiln profile: ✄
Cooler: grate: details✄

  • 1968-1978 Oil(2)
  • 1978 to date: coal - later supplements ✄

Coal mill: ✄
Exhaust: two Sturtevant electrostatic precipitators in parallel before ID fan(1).
Typical Output: ✄
Typical Heat Consumption: ✄


  • (1) pamphlet 1970
  • (2) Jackson p 277
  • (3) Cement Technology 1970

Sources: Jackson, pp 221, 277: “Cookstown Works, Northern Ireland”, Cement and Lime Manufacture, 41, January 1968, p 13: “A new cement works at Cookstown”, Cement Technology, 1, 1970, pp 7-16: Cookstown Works (pamphlet), Blue Circle Publicity Department, 1970.