The Phurnacite plant, the briquette
In the mining of coal, small coal has always been a problem. Even in the days of hand cut, small coal was not paid for and men were sacked for loading too much small coal in their trams. Thousands of tons were tipped in south Wales as waste. Since the war, a lot of these have been cleared but there is still a difficulty in using up small coal, especially in south Wales with its Anthracite and low volatile steam coal is the obvious way to make large coal out of small coal is to combine the smaller pieces together. This is what briquetting does. The most common binder is pitch. Pitch is a residue left when coal tar is distilled. Many other materials have been used from time to time with varying success, but for various reasons, pitch is a binder generally used. The west Wales farmers used to mix Anthracite fines with clay and a little water, puddle into a ball and dried.
The resulting briquette known as Lucm was uses as fuel. Apart from being a messy fuel to make, it was also messy to burn, due to the powdery ash of burnt clay. Other binders used include:
- Crude Oil
- Sodium Silicate
- Sulphite Lye
The disadvantages of some of these binders are high cost and lack of water proofing qualities among other things. The advantages include smokeless ness because pitch when burnt gives off a large volume of heavy fumes. Briquettes have been made without binders but are generally used locally as a domestic fuel to minimise breakage due to handling.
The classic pitch bound block briquette made in south Wales consisted of blending coals. That is steam coal with bituminous, so that the block would tend to cake as it burned and minimised crumbling.
A typical briquette would contain
- Bituminous coal - 25%
- Steam coal – 45%
- Dry Steam coal – 22%
- Pitch – 8%
Such a briquette could be stored in all weathers and climates. Both Scott and Shackleton took crown briquettes to the Antarctic. The built their stables from them and as the horses where consumed as meat, the stables were consumed as fuel. Some of the blocks were returned to the works after thirty years in the frozen waste and were proved to be as good as when they were dispatched.
Although briquetting has been known as worked commercially for over 100 years, it was not until the beginning of this century that a roll press was used giving an ovoid or “boulet” generally about the size and shape of an egg. These where intended for the domestic market and disadvantages of giving off heavy smoke in the early stages of combustion. A lot of work went into the production of smokeless fuel. Trial with smokeless binders proved negative and carbonisation seems to be the answer.
The original Phurnacite had as its objective- Cynheydre anthracite reckoned to be the finest coal in the world. Phurnacite came pretty close to when suitable coals were available, but the very high standard of Ash content, caloriphic value and smokeless ness could never be equalled.
Between the wars compensation for injuries received underground would cease if the man could be found a job, even a light one with the company. This fact coupled with the problems already stated of small coal gave rise to a project by Powell Duffryn Limited to work out a way to kill two birds with one stone, using their small coal and saving compensation payments (getting men to work for the money). One scheme of mixing pulverising coal with oil proved successful for transatlantic liners but for some unknown reasons was dropped.
A plant for the manufacture of briquettes was set up near the washery middle Duffryn. Ovoids were produced there in the early 1920’s. In the late 1930’s Powell Duffryn together with Humphries in Glasgow, embarked on a project to make smokeless fuel using a re-taught process and to expand the works. Following a complaint from France about a shipment of dry steam coal, the engineer at the time went to investigate and came across a plant using the Disticoke ovens. On return, the re-taught method was dropped and a Disticoke battery was built. Tow presses were ordered from France and when the war broke out in September 1939, the two presses were at a northern French port, when France fell in 1940, the two presses remained crated throughout the war. During this time the plant was worked using the two old presses. The plant worked on a two shift - days and afternoons. The ovens were on a 24 hour cycle, this continued until after the war. The actual buildings were designed with a view to expansion and a third press was put into use in 1951.
The estimated life of a battery was 15 years, so number 3 battery was worn-out but the demand got so great it was decided to build more batteries and another briquetting plant. Number 2 plant with two presses and number 3 battery came into operation in 1957. Number 1 battery, which came into action in 1942 was taken out in November 1957. That was 15 Years 9 months, 9 months over its life expectancy. It was entirely re-built and reopened in September 1961. Number 6 battery was opened in 1966/67 and number 7 was opened in 1970. At the same time as a new 40ton press was installed, number 3 battery closed in 1974. The battery had been out of action since that date, various reasons have stopped it being re-built for example the planning permission hadn’t been granted.
Nationalisation of the plant was in 1947, when the coal industry was nationalised. The works were in the Number 4 area as a part of the local mining complex. Then in the early 1960’s the Coal Products Division was formed. Which took in patent fuels, coking plants and by-product works. In the 1970’s this was again reorganised and National Smokeless fuels N.S.F was formed to take over the manufactured fuels industry.
The plant has reached its peak of production an will probably be run down during the coming years. This is due to the fact that as the South Wales pits have been worked out and closed, suitable coals will not be available in sufficient quantity for economic working. The pollution problems will also contribute to the eventual close down.