|1940s Tunnel Brand|
|Big T Brand used from the late 1960s|
Clinker manufacture operational: 1949 to date
Approximate clinker production to 2015: 31 million tonnes (13th)
The plant was one of several post-war projects that were somewhat delayed by the economic circumstances of the late 1940s: it was originally scheduled for start up in 1947. It was the last green-field plant location to be remote from both raw materials and its position seems to have been predicated by the rules of the then-existing pricing cartel. Even water was not available on site: it was pumped from an artesian well 8 km away. Both raw materials are brought by rather arduous trips on minor roads through a semi-urban area. The use of colliery waste, with a potential fuel saving, was not new: it had been employed at Cousland much earlier. Despite the obvious suitability of dry process, FLS were uninterested in this, and the plant used standard wet process as previously installed by them at many other hard-rock sites such as Hope, Ketton, Drogheda, Limerick and Ribblesdale. By the 1960s, however, they had started to develop “long dry” kilns, and A3 became a successful first venture in Britain. The carbonaceous rawmix made it peculiarly appropriate in this instance. It had a long service life.
The need to maintain capacity while getting rid of the wet kilns necessitated its replacement with the highly-efficient A4, which for the first time allowed full utilization of the potential heat content of the raw material.
The plant is on the Wrexham to Connah’s Quay branch railway and could use this initially for shale movement (from Llay Main’s siding when it still operated) as well as coal and despatch. Now only coal arrives by rail, and the plant transport is nearly all by road. The A55, 3 km away, gives rapid access to the motorway network.
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, except where already published (see references).
Four rotary kilns were installed:
Rotation (viewed from firing end): clockwise
Kiln profile (from cooler ports): -3000×3300: 34000×3300: 35750×3000: 62750×3000: 65000×3450: 97250×3450: 97250×3000: 98000×3000: tyres at 3000, 32000, 59000, 86000: turning gear at 56000: dust return at 61000.
Cooler: Unax planetary 10×6.30×1.400
Fuel: 1950-1970, 1975-2005 Coal: 1970-1975 oil
Coal Mill: indirect: 410 kW Tirax ball-mill common to A1 and A2 with oil-fired drying air
Typical Output: 1950-1966 415 t/d: 1966-2005 420 t/d
Typical Heat Consumption: 1950-1956 7.10 MJ/kg: 1957-1966 6.75 MJ/kg: 1966-2005 5.70 MJ/kg
Operated: 12/1949-1991, 1995-2005
Location: Hot end (cooler ports) 329214,362104: Cold end 329122,362137: hot end enclosed
Dimensions (from cooler ports): Metric 98.00 × 3.000BC / 3.450D
Kiln profile (from cooler ports): -3000×3000: 62750×3000: 65000×3450: 97250×3450: 97250×3000: 98000×3000: tyres at 3000, 32000, 59000, 86000: turning gear at 56000: dust return at 61000.
Cooler: Unax planetary 10×6.30×1.200
Typical Output: 415 t/d
Typical Heat Consumption: 1949-1956 7.10 MJ/kg: 1957-1966 6.75 MJ/kg: 1966-2005 5.60 MJ/kg
Identical in all other respects to A1
Process: Long dry
Location: Hot end (cooler ports) 329203,362087: Cold end 329083,362129: hot end enclosed
Dimensions (from cooler ports): Metric 128.00 × 4.150BC / 4.550D
Rotation (viewed from firing end): anticlockwise
Kiln profile (from cooler ports): -3300×4150: 85000×4150: 88000×4550: 128000×4550: tyres at 3500, 34500, 74000, 113500: turning gear at 69000.
Cooler: Unax planetary 10×13.00×1.600
Fuel: 1966-1970, 1975-2005 Coal: 1970-1975 Oil
Coal Mill: indirect: Tirax ball-mill
Typical Output: 930 t/d
Typical Heat Consumption: 3.95 MJ/kg
Operated: 26/07/2005 to date
Process: air-separate precalciner: details ✄
Location: hot end 329138,362045: cold end 329076,362067: unenclosed
Rotation (viewed from firing end): anti-clockwise
Kiln profile: ✄
Cooler: grate: details ✄
Coal mill: ✄
Typical Output: ✄
Typical Heat Consumption: ✄
Sources: Jackson, pp 248, 291: Tunnel Cement (brochure), Tunnel Portland Cement Co., Ltd., 1950: Mervyn E. Foulkes, “The History of Cement Manufacture at Padeswood, North-east Wales” in Magazine of the Buckley Society, 28, 2004: Mervyn Foulkes also produced a video: A History of Cement Making at Padeswood Works in North Wales, Knew Productions, 2006 - the motivations for the production of this video were essentially the motivations for making this website - it is highly recommended.