Cement Kilns: Burham

Burham Brand. Although superceded in Britain by the "Blue Circle" in the 1920s, the brand continued in use for some export markets well into the 1960s, and continued in use as a brand in Nigeria until 2015. The central object represents an early form of tensile strength specimen.

Location:

Grid reference: TQ71876075
x=571870
y=160750
51°19'12"N; 0°28'0"E
Civil Parish: Burham, Kent (north end) and Aylesford, Kent (south end)

Clinker manufacture operational: 1854-1938

Approximate clinker production: 5.0 million tonnes

Raw materials:

From 1854 to 1869:
- Chalk: (probably Holywell Nodular Chalk) bought in - perhaps from Formby's
- Medway alluvium
From 1869 to 1914:
- Lower and Middle Chalk from Upper Culand pit (573850,161850) yielding:
  - West Melbury Marly Chalk Formation: 97-100 Ma: 5%
  - Zig-zag Chalk Formation: 94-97 Ma: 67%
  - Holywell Nodular Chalk Formation: 92-94 Ma: 27%
  - New Pit Chalk Formation: 90-92 Ma: 1%
- Middle and Upper Chalk from Bluebell Hill pit (574160,162090) mainly for white lime, yielding:
  - Holywell chalk: 1%
  - New Pit chalk: 51%
  - Lewes Chalk Formation: 88-90 Ma: 48%
- Upper Gault Clay (100-105 Ma) from the main brick pit at 572300,160900
- From 1908 to 1938:
  - Lower Chalk from Lower Culand pit (573700,161400), yielding:
    - West Melbury marl: 40%
    - Zig-zag chalk: 60%
  - Gault Clay
Ownership:
- 1854-1859 Thomas Cubitt and Co.
- 1859-1871 Webster and Co.
- 1871-1900 Burham Brick, Lime and Cement Co. Ltd
- 1900-1938 APCM (Blue Circle)
The plant was initially primarily concerned with brick making, using the Gault Clay quarry immediately adjacent to the plant, but also made hydraulic lime and Portland cement. The initial installation was described on its sale in 1859 as "consisting of engine and house, washing mills, some four kilns, with accompanying drying stoves and nine coking ovens". The four wet process bottle kilns increased to nine (216 t/week) by 1869. During 1872-1877, a further 13 kilns were added, bringing output to 578 t/week. A further eight kilns were added in 1878-1881 (total 810 t/week) and 16 more in 1885-1893 (total 1284 t/week). These kilns constituted a more or less continuous long row extending 250 m along the Medway bank. From around 1895, some of the bottle kilns were replaced with Batchelor kilns, and seven were converted to shaft kilns, converted again to Schneider format around 1901. By 1901, the complement was now 19 bottle kilns (493 t/week), 17 chamber kilns (510 t/week) and 7 shaft kilns (560 t/week) – total output 1563 t/week. In 1906, another five chamber kilns were added. With the advent of the rotary kilns, the remaining bottle kilns and the last block of chamber kilns were removed.

Rotary kilns were installed commencing 1911, to form what was at the time one of the country’s most up-to-date rotary plants. The tenuous justification for this was typical of the early APCM management style. Burham was very badly situated: it lacked any sort of landward transportation link, and its barge transport via the Medway was unsuitable for 20th century operations, since only small barges could negotiate Rochester Bridge. However, at the time of acquisition, the plant was substantially mortgaged, and continued development of the plant was necessary in order to avoid foreclosure. The plant was described in detail in the APCM 1924 schedule. The rest of the chamber kilns and the Schneider kilns remained in place, and were occasionally used as top-up capacity. They last operated in 1927. The plant shut down in 1930, and kiln A4 was moved to Harbury to become kiln B2. The remaining kilns were re-started briefly in 1934 and again in 1936-1938, sending clinker by barge to Martin Earles and Crown and Quarry for grinding. The kilns were moved elsewhere: kiln A1 to Masons as kiln A4, and A2 and A3 to Golden Bay (New Zealand). The plant formally closed in 1941, but it ceased to produce clinker in 1938. The structures were demolished, and the site was abandoned as waste. The backwater of the Medway on which the plant was situated, produced by the straightening of the river in the 1830s, could only be maintained navigable by constant dredging, and has now practically silted up. Foundations, slurry backs and three slurry mixers are still present, thickly overgrown. The quarries are waste land.

Power Supply

The original plant was directly driven by steam engines. The pre-war kilns were also operated by direct steam power. In 1920 the kiln section was electrified, with five generators driven by gas engines. Purchased power was never used.

Rawmills

Washmills were always used. In the 1912 rotary kiln plant, there was a 120 kW washmill, two 50 kW screening mills and two 75 kW tube mills used in series, located on the edge of the clay field at 572110,161090. After installation of kiln 4, the tube mills were removed, and a further two screening mills were added.

Four rotary kilns were installed:

Kiln A1

Supplier: Ernest Newell
Operated: 1912-1930, 4/6/1934-5/11/1934 , 1936-8/1938
Process: Wet
Location: hot end 571883,160709: cold end 571865,160768: hot end enclosed.
Dimensions: 202’0”× 10’0”B / 8’6”CD (metric 61.57 × 3.048 / 2.591)
Rotation (viewed from firing end): anti-clockwise
Slope: 1/25 (2.292°)
Speed: 0.65-1.3 rpm
Drive: 30 kW
Kiln profile: 0×2591: 1981×2591: 3429×3048: 15621×3048: 17069×2591: 61570×2591: Tyres at 1372, 17678, 36576, 52730: turning gear at 19202
Cooler: rotary 80’6”× 6’4” (metric 24.54 × 1.930) beneath kiln
Cooler profile: 0×2078: 775×2078: 6039×1930: 24536×1930: Tyres at 3810, 18745
Fuel: Coal
Coal Mill: indirect: supplied by a central milling section consisting three roll crushers, two dryers and eight Griffin mills, shared by kilns 1-3. A further three Griffin millls were added when kiln 4 was installed.
Exhaust: direct to stack
Typical Output: 168 t/d
Typical Heat Consumption: 8.60 MJ/kg

Kiln A2

Operated: 1913-1930, 4/6/1934-5/11/1934, 1936-8/1938
Location: Hot end 571891,160712: Cold end 571873,160771: hot end enclosed.
Identical in all other respects to A1

Kiln A3

Operated: 1914-1930, 4/6/1934-5/11/1934, 1936-8/1938
Location: Hot end 571900,160715: Cold end 571882,160773: hot end enclosed.
Identical in all other respects to A1

Kiln A4

Supplier: Vickers
Operated: 1920-12/1930
Process: Wet
Location: Hot end 571909,160717: Cold end 571891,160776: hot end enclosed.
Dimensions: 202’0”× 9’10½”B / 8’10½”CD (metric 61.57 × 3.010 / 2.705)
Rotation (viewed from firing end): ?
Slope: ?
Speed: ?
Drive: ?
Kiln profile: 0×2705: 3124×2705: 4191×3010: 15164×3010: 16231×2705: 61570×2705: Tyres at 2134, 17221, 35509, 53797: turning gear at 33528?
Cooler: rotary 71’11¼” × 6’4” (metric 21.93 × 1.930) beneath kiln
Cooler profile: 0×2553: 6077×2553: 7449×1930: 21927×1930: Tyres at 4858, 19844
Fuel: Coal
Coal Mill: indirect: see A1
Exhaust: direct to stack
Typical Output: 179 t/d
Typical Heat Consumption: 8.68 MJ/kg

Sources::
- Primary Sources:
  - Greenhithe Archive
  - W A Brown, pp 109-111
  - APCM 1924 schedule
  - Ordnance Survey 1:2500 mapping
  - BGS mapping and monographs
- Confirmatory Sources:
  - Eve, p 31
  - Francis, pp 186-188
  - Jackson, pp 217, 274
  - Preston, pp 72, 77, 85, 170, 174, 200-201
  - Pugh, pp 13, 16, 23-24

William Alden Brown included the following description of Burham:

Process: Wet

Materials: Chalk and clay

Weekly Capacity: 3,000 tons.

Chalk Quarry: Steam navvy capacity 80 tons per hour.

Clay Quarry: Steam navvy capacity 40 tons per hour—three locomotive engines and 6 cubic yard capacity side-tipping cars.

Chalk quarry 1½ miles from the washmill; clay quarry half a mile from the washmill.

Grinding the Raw Materials:

Washmill (coarse gratings)
Washmills (fine gratings)
Two tube mills (6 × 26 feet)
Three sets of three-throw ram pumps

Average running hours 65 per week full capacity.

Slurry Storage and Mixing:

Three circular storage tanks 66 feet diameter × 10 feet deep.
Three sets of three-throw ram pumps.

Rotary Kilns for Burning:

Three rotary kilns (9 feet diameter × 200 feet long).
Three rotary coolers (6 feet diameter × 80 feet long).

Average running time 50 full weeks per year, allowing each kiln off two weeks during the year for relining in firing zone and minor repairs and adjustments.

Coal Crushing, Drying, and Grinding:

One crusher
One dryer (5 feet diameter × 60 feet long).
Eight Griffin mills.

Average running time 120 hours per week.

Grinding the Clinker:

Eight ball mills (No. 8).
Eight tube mills (5 ft. 6 in diameter × 27 ft. long).

Average running time 120 hours per week.

Cement Storage:

Low frame buildings divided into bins by timber partitions.
Capacity 15,000 tons.
Packing, hand labour.

Cooperage:

Stave Department
- Four multiple stave jointers.
- Four stave tonguing and grooving machines.
- Two stave chiming, crozing, and printing machines.
- Two 80 ft. stave heating stoves.
Trussing Department
- Eight adjustable trussing bells for different sizes barrels.
Heading Department
- Four head rounding machines.
- Three treadle head compressors.
- One circular saw.
- Two tonguing, grooving, and thickening machines.
Iron Department
- Four hoop riveting machines.
- Four hoop splaying machines.
- Three multiple hoop punching and shearing machines.
Hydraulic Plant
- Two accumulators.
- Four sets pumps.
Machine Shop
- One circular saw sharpener.
- One automatic cutter grinding machine.

Power required: 70 to 80 horse-power. Average running hours 60 per week. Output 12,000 barrels.

Sack Department:

Sack storage capacity for 200,000 sacks.
One sack-cleaning machine.
Drying apparatus.
Two sewing and darning machines.

Power Plant:

2,500 horse-power.
Three compound engines: one 1,500 h.p., two 500 h.p. each.
Eight Lancashire boilers.

Note.—The apparent large boiler capacity is due to the arrangement of the works, three separate power plants being laid down, each having one engine, viz. :—

One 500 h.p. engine for raw grinding with two boilers.
One 1,500 h.p. engine for cement grinding with four boilers.
One 500 h.p. engine for kilns and auxiliary machinery with two boilers.

Power Supply

Rawmills

Kiln A1

Kiln A2

Kiln A3

Kiln A4