The Phurnacite plant, it's problems
Pitch being a skin irritant, working conditions were very poor in the early days and as far back to 1911 regulations required that bathing facilities should be provided for patent fuel workers. Nowadays, with adequate bath facilities and a use of proper barrier creams coupled with far better operating conditions most of the hazards have gone from the fuel worker’s jobs.
In order to eliminate pitch dust from the atmosphere at the plant, liquid pitch was introduced in the mid 1970’s. This resulted in a very poor briquette. Various things were tried to remedy this. Good results were obtained by addition of Sulphite lye to the mixture. However, this produced an obnoxious smell, which could not be eliminated, Molasses were tried in its place with almost similar results. Their factors combined with the public’s awareness of pure air, resulted in demonstrations or protests from the local people. Pollution is always a problem in any plant; it was the major issue and threatened to close the plant.
In the late 1960’s, the Balfour process was brought in, to try to control pollution. The process consisted of a large retort. Ovoids were fed into the top and carbonised. They were then let out through the bottom, through a gravity system. Once in operation, the volatile matter (Gas) could be used to heat up the retort for carbonising and inert gas (NITROGEN) was used to prevent combustion of the Ovoids. The proves could be called a continuous or flow process, besides low pollution, was that the unit could be shut down easily, without any damage, which would occur when a disticoke battery is shut, due to strikes, etc. However, a serious fault kept recurring with the solesand and the fantips. Although some of the finest retort and disolation engineers were called in, they failed to overcome the problem and the system discontinued, in the early 1970’s. This whole operation cost quite a great deal of money, but only shows the extent to which the national coal board is prepared to go to overcome the pollution problem of the phurnacite plant.
A system of burning off the fumes with the use of propane gas, although very expensive, is in operation. Another mixture tried in briquetting was the addition of sulphate ammonia to the raw coal at the blending site. Although this did improve the fuel slightly, the damage it caused to the machinery dryers etc, outweighed any benefit it had, it was later tried on an expensive system of being fed the coal, just before the pug. This still resulted in corrosion and was discontinued, when the pitch was changed from being fed directly into the pug, to being fed with the coal in the cage mill. Though agreeing, that the pollution caused by the plants is bad, it must also be considered, the contribution it makes to the national clean air. Without phurnacite production of roughly 75,000 tonnes per year, a greater amount of coal would have to be burned and although spread out, the pollution is bound to be greater. The weather conditions have a considerable effect on pollution. Research over a long period of time shows that pollution is greatest in bad weather, irrespective of production figures or plant times of charging. The workmen have been accused of not using the machinery properly but this is denied, as everyone at the plant is concerned because they realise that continual complaints can close the plant and everyone will be out of work.
Another problem facing the works is the shortage of coals suitable for the phurnacite process, which originally used Aberdare dry steam coal. The blending of bituminous and low volatile coal is difficult, when coals available but without suitable coals it becomes impossible it is reported from time to time, that trees in the Duffryn woods, close to the plant are being killed off, yet the new trees in the area which were planted, when the tip was removed some years ago are thriving. Most of the trees dying off are the result of underground fires. The pollution control cabin is manned at all times and everything possible, is done to satisfy the public. Machinery, being very old, is also a problem. It is hard to keep it in running order, due to machines being run for such long periods and the scarcity of replacement parts.