Dust Emissions on the Thames

In April 1948, the question of cement industry dust emissions on Thamesside was debated in Parliament. A certain amount of objective data was presented and the Government's position was stated. It forms the basis for a discussion of how control of dust emissions was progressing after WWII. The debate can be found in Hansard 450: Adjournment Debate Thursday 29 April 1948.

Motion made, and Question proposed, "That this House do now adjourn."—[ Mr. Joseph Henderson.]

11.59 p.m. Mr Solley (Thurrock Note 1)

The House has been listening to much talk about monopolies, and I should like to draw attention to one particular kind of monopoly, the cement monopoly. I do not propose to deal with the cement industry at large, but only with certain of its activities which seriously affect thousands of people on both sides of the Thames Estuary, and in particular in my constituency of Thurrock.

In Thurrock we have the Tunnel Portland Cement Company, the Alpha Cement Company, and the Wouldham Cement Company, which is a subsidiary of the British Portland Cement Manufacturers Limited. On the south side of the Thames there are a number of works—the Kent Works, the Swanscombe Works, Bevan's Works and Johnson's Works (Note 2). During the process of the manufacture of cement large quantities of finely ground solids enter the kilns and consequently the kiln gases are heavily laden with dust particles. Although perhaps not accurately as regards scientific analysis, usually this is referred to as cement dust.

The effect of this cement dust is as follows. About 65 tons of it are deposited per square mile of the area in question every month of the year (Note 3). When the wind is blowing from south to north, the cement dust produced by the Kent works find their deposit on Essex soil, and when the wind is blowing from north to south, the cement dust produced by the Thurrock works find their deposit on Kent soil. This figure of 65 tons per square mile per month is three times larger than the average pollution of the atmosphere of ordinary industrial areas.

The effect of the cement dust in the domestic domain is extremely serious. If windows are opened within a mile of these works, furniture inside the rooms become quickly covered with a fine layer of dust. Clothes which are kept on the line become covered. A few weeks ago I had a letter from one of my constituents, a lady who said she could not hang the children's "nappies" on the clothes line because they soon became covered with a layer of dust. The houses and trees next to these factories are smeared with cement dust. One can almost see a "white Christmas" in midsummer. The effect of these conditions on the health of persons living in the area is a matter on which medical opinion cannot speak with direct authority (Note 4). Subject to this, there is no doubt that a considerable amount of anxiety and worry is engendered in the minds of housewives who have to fight valiantly against these extraordinary and difficult conditions.

The question therefore arises: how can this evil be avoided? I must tell the House it can be avoided, and avoided completely. A book published in 1934 by the works superintendent of the Associated Portland Cement Company, Mr A C Davies, which I believe to be a standard textbook on portland cement (Note 5), describes three main methods of avoiding this nuisance. It is interesting to note, with reference to the most efficient method of electrostatic precipitation, that this was first described in detail in the design of Cottrell in 1911 (Note 6). It is of further interest that the physics experiment which suggested the development of an electrostatic precipitator was started as long ago as 1824, the year that the Aspdin (Note 7) patent for Portland cement was filed. We had to wait over a hundred years in the course of industrial development before industry thought it worthwhile to develop a really efficient method of doing away with this cement dust nuisance.

The question arises why these cement monopolies have not taken adequate steps to remedy these nuisances. The answer is not far to seek. There is no doubt that the capital outlay in respect of these plants for dealing with cement dust, is fairly substantial, and the running costs are by no means insignificant. We arrive at this deduction, that the making of bigger and fatter profits, which is the be-all and end-all of the existence of the cement combines, is carried on with complete disregard for the public, and for the common law duties of the combines not to create any public nuisance. For instance, as far as my constituency is concerned, it was almost ancient history when the Thurrock Urban District Council came into being, in 1936, and it was one of the council's first tasks to consider this question of the public nuisance caused in Thurrock.

From then onwards, representations have been made at intervals by the inhabitants to the council, and by the council to the representatives of the cement industry. In 1938, in the case of the Tunnel Cement Works, there were certain kilns in operation, and as far as kilns 4 and 5 were concerned there was only one electrostatic precipitator between them. Kilns 1, 2 and 3 were pumping poison into the atmosphere of Thurrock with complete disregard for the health and convenience of the public. In 1948, we find, with respect to the same works, that kilns 1 to 3 are still without electrostatic precipitators (Note 8).

Before the war the cement industry had no excuses about the shortage of steel; they had no excuse about difficulties of getting apparatus. Their only real excuse was that they were too stingy to spend money to safeguard the public from this nuisance. Today, under the pressure of the urban district councils on both sides of the Thames, councils which are under Labour jurisdiction, the cement companies have suddenly decided to do everything they can to remedy this nuisance. But of course, there is a snag in this apparent readiness; they put the blame on the Government and say that they cannot get the necessary steel. It is interesting to note that they should have waited until there was a Labour Government and they could make these excuses, when before the war they could have remedied the nuisance.

I know that the Minister will say that we must have regard to the shortage of steel and to the necessity of increasing production in the interest of the export drive, but I would say to him that, as far as this nuisance is concerned, I am confident, in the light of my researches and with such knowledge of the law as I possess, that the cement companies are guilty of a public nuisance. I am confident that any of the local authorities concerned could take civil proceedings in order to counteract this nuisance, and, in this connection, it is interesting to note that His Majesty's judges have ruled that it is no defence to a charge of this nature to say that the nuisance arises from the carrying on of a trade beneficial to the community, and that the nuisance is less than the advantage from the trade.

I submit that the Government ought not to say, as I fear may be said, that we are passing through a difficult period and that, on the whole, it is better that production should carry on in its present form rather than that there should be some temporary hold-up caused by the allocation of steel for the manufacture of the necessary equipment. In a sense, if the Government took up that attitude, they would be aiding and abetting the commission of a public nuisance, and I sincerely hope they will avoid that conclusion.

Just one further word on the question of exports. A tremendous amount of cement is being exported, and if the allocation of steel for this plant would necessarily remove from the sphere of exports a corresponding amount of goods, having regard to the fact that cement is one of our priority exports, this amount of steel could surely be well allowed. I ask my hon. Friend to say that he will do all he can in this matter — a matter affecting thousands of people residing on both sides of the Thames.

12.12 a.m. Mr. Dodds (Dartford Note 9)

am grateful for the fact that my hon. Friend has included in his damning indictment people on both sides of the Thames. I speak for the Kentish side of the river, where for more than 20 years the residents have had to put up with this scourge. It is time that effective action was taken. Kent is referred to as the "Garden of England" but only too often, and particularly during the summer months, the whole countryside is covered by a layer of grey cement dust. I well remember last summer that the people throughout the country had the benefit of an excellent summer, but in Kent—and I am sure it must have been the same in Thurrock—everything was covered by this cement dust. There was to be seen cement dust everywhere. Windows in the houses had to be closed because of the fact that the housewife had a terrific job with the dust which was coming in when the windows were open.

Now, it is rather interesting to note that an investigating committee which has been formed of representatives of the local authorities have met representatives of the cement works in the Dartford district, and they were specifically informed that the policy of the cement works was to control this dust nuisance but that this has been seriously interfered with because they cannot get the machinery necessary for the task. I few days ago, at a public inquiry in Lavington, in Wiltshire (Note 10), where the cement people were making application to go ahead with some works in that beauty spot, it was mentioned that if approval were given, machinery would be introduced which would completely obviate the cement dust nuisance in the district. We in the Dartford district feel that if that is correct, we have had for a long time, and are continuing to have, a very raw deal indeed, and we look to the Parliamentary Secretary to inform his right hon. Friend that, so far as the social work and the great activities of the Ministry are concerned, it can have little effect in Kent unless this dust is dealt with. We hope that some statement will be made tonight of the steps to be taken to ensure that this scourge will not last for one day longer than is necessary.

12.15 a.m. The Parliamentary Secretary to the Ministry of Health (Mr. John Edwards Note 11).

My hon. Friend has drawn attention to what, it will be admitted, is an extremely difficult problem, and I would not seek to minimise it in any way. Dust is a very great evil, and I am sure that to those who live in these areas it must be highly annoying. I would not want it to be thought however that there was any evidence to support the view that cement chimney dust causes a direct danger to health (Note 12). My hon. Friend the Member for Thurrock (Mr. Solley) who started this discussion tonight, suggested that there was a doubt, but there is no doubt whatever that cement chimney dust — which, let me make it plain, is not cement, but fine particles of clay and dust which come out of the kilns — does not have a direct effect on health. That does not mean that it is not annoying in a hundred and one ways, but I do not want to be alarmist about it.

We cannot be indifferent to the economic aspects of this question. The works in the region produce one-half of the cement made in Britain - 4,500,000 tons a year (Note 13). There is no comparable region in the world (Note 14). By far the largest export of cement comes from this area. Therefore, it is not, so I am advised by my colleagues, possible to let up in production because of the terrific need we have for cement both at home and overseas.

May I now turn to the aspects of this question which concern my Department? The law relating to cement works says that the owner shall use all practicable means (Note 15) of preventing the escape of fumes, and these words have reference not only to the erection and maintenance of appliances but also to the proper supervision and use of them. Cement works have to be registered with my Ministry (Note 16), but it is only since 1935 that such works were added to the schedule of the Alkali Acts, and since then new works have had to have the best appliances from the start, and existing works have had to provide such appliances (Note 17). We have special inspectors in the Department concerned with all the works under the Alkali Orders, and they are in the closest touch with all the firms. In anticipation of the discussion tonight, I spent part of this morning talking about the question with them, and I hope in due course to go and see the whole thing for myself. I would have gone today, but in the time available it was not possible for me to get away.

I would like to say, in justice and fairness, that in our experience the managers of the cement undertakings in this area are willing to co-operate not only in the field where we have statutory control, the high-level emission of dust, but in the field of low-level emission of dust where we have no powers at all. I do not think that, in fact, from the time we had statutory powers, their record is open to very much criticism. After the cement works were put under this order in this area, that is, from 1935 to the outbreak of war, we got 18 electrical precipitation appliances in operation. In those days plants cost something like £30,000 or £40,000, and over that period, although things were not wholly satisfactory, there was considerable progress. But for the war we should, by the exercise of our powers, have got the Thames-side cement industry into the right position in relation to prevention plants. The war knocked that on the head, and there is a quite genuine difficulty at present in getting delivery of the plant.

I do not need to talk about the competing demands for steel for all the various purposes essential to our economic survival (Note 18). I would not deny that it is easy for me departmentally to make an extremely good case for steel for certain purposes, including purposes of this kind and for electrical precipitation units, but the fact remains that when the allocation of steel is made, and all the other competing claims taken into consideration, then the allocation just does not permit, within the bulk allocations, anything but a quite small output of this type of plant.

Especially in the light of what I have heard tonight, I will certainly do all I can to push forward the production of precipitation plants, but I would not want to mislead anyone on that point, because the allocation of steel is so limited that what it might be open to me to do is also limited, and until we get an improvement in the steel position I am not very hopeful of our being able to do anything very rapid. I have a list of what is being done at present. Some of the plants in this area have, in fact, got precipitation plants in process of erection, others have plants being overhauled because they have got badly "out of trim" during the war, and others have got precipitation plants on order.

I can assure hon. Members that we shall, through our alkali inspectors, do what we can to get a move on here, but I would say that our major difficulties are in the supply of steel, and not difficulties at the present time on the part of any of the cement firms. Although our discussion has largely been concerned with the high-level emissions which cause widespread troubles, we have made considerable progress since the war in dealing with low-level emissions where the problem is localized in character, and where we are not held up in the same way by shortages of materials. There may be one or two points I have not dealt with, but I have taken note of all that has been said in this discussion, and shall take a further opportunity of going into the matter with my advisers.

12.25 a.m. Mr. Pritt (Hammersmith, North Note 19)

It seems to me that the Minister has disclosed rather a serious position and one in which he might be able to bring forward some stronger case for the allocation of steel for this purpose. He is admitting and condoning a position in which a continuous series of public nuisances is being caused by an industry which is no doubt doing a very useful task. But if the local authorities were doing this duty, the problem would be solved in a few months because, having obtained an injunction, these factories could be shut down. If an injunction were obtained, the court might perhaps suspend its operation while someone got busy making this plant.

Question put, and agreed to.

Adjourned accordingly at Twenty-six Minutes past Twelve o' Clock

In 1948, Britain was still suffering desperately from war damage. The cement industry, although it suffered relatively little from direct enemy action, was still significantly affected. It had been in rapid expansion mode in the late 1930s following the earlier depression, but with the war, all new projects were suspended. The industry ran flat out to begin with, supplying the construction of defences and airstrips. This was achieved with a rapidly diminishing workforce due to conscription, so that cement plants were "run into the ground" with little maintenance. By 1944, when the tide of the war had turned, cement manufacture became a low priority, and production reduced dramatically, with much of the plant shut down in a state of disrepair.

After 1945, cement production once again became a priority, for national reconstruction and to rebuild an export market to get desperately-needed foreign exchange. A process of rapid patching up began.

All these events took place against a backdrop of concern about air pollution. Although cement plants had been subject to complaints about fume emissions virtually from the start of the industry in the 1850s, the question of dust emissions only became prominent after the introduction of rotary kilns in the first decade of the 20th century. See for example Wouldham (1902) and Lyme Regis (1912). The industry mainly responded to the avalanche of complaints following rotary kiln installation by - reluctantly - building much taller chimney stacks. These spread the fallout over a proportionally wider area and therefore reduced the density of deposition.

As mentioned in the debate, the use of electrostatic precipitator in the cement industry was developed in the USA from 1911. The technique was first employed in the UK at urban Wishaw plant, following injunctions from the local authority. This was followed by installations on all four kilns at Johnsons in 1933.

From 1929, chain heat exchangers started to be installed in wet kilns. The primary effect of these was to increase the production capacity of the kiln by 20-50%, with obvious economic advantages. These could result in a reduced dust emission, but more often than not, with increased capacity, dust emission increased.

In 1934, as mentioned in the debate, the latest edition of A C Davis's textbook on cement manufacture was published. This contained a chapter on dust collection, discussing a variety of techniques. Naturally, the chapter was worded very carefully to give no endorsement to any particular technique, but by providing some numerical data - 60-80% efficiency from cyclones, and 95% from electrostatic precipitators under certain limited conditions - readers might reach the conclusion that the latter was the "best".

In 1935, in response to gathering public concern, the Alkali Inspectorate were given statutory powers specific to the cement industry. Regulations required that unspecified "best practicable means" should be used for dust control. Gradually, with a large amount of input from the industry, a set of vague definitions of these means emerged. EPs were identified as best means for large plants, but were considered too expensive for smaller plants. For the latter, "a good chain system within the kiln will probably suffice". It was said that feed emerging from the hot end of the chain system "should normally contain about 12% moisture". This will raise a smile from anyone familiar with real-world wet kiln operation (Note 20). A particular development during the 1930s was Vickers Armstrong's supply of kilns with enlarged cold ends, provided with chain systems. These evolved into the Desiccator kiln, many of which were installed towards the end of the decade with Inspectorate approval, with no further dust control.

The concession that chain systems could be, in some cases, the "best practicable means" infected the Alkali Inspectorate's thinking for many years, and allowed the cement companies to ride roughshod over the regulations. In any case, the Inspectorate was always reluctant to use its regulatory powers, in view of their "close relationship" with the cement firms alluded to by the minister (Note 21). However, in case where a plant was planning to increase capacity, permission to instal a new kiln could be withheld unless the new kiln - and other older kilns - were provided with precipitators. So for instance, with the installation of Swanscombe kiln 4 in 1935, it was provided with a precipitator, and precipitators were also added to the three 1929 kilns, which originally had no dust control. Similar events took place at Wouldham in 1936, West Thurrock in 1937, Hope in 1953, Rochester in 1955 and Rugby as late as 1967. However, the last new kiln to be installed without a precipitator was Chinnor B1 as late as 1962.

In the end, the Inspectorate waited to be galvanised into action by public annoyance. Bad pollution events in 1962 led to a much more acrimonious Adjournment Debate in parliament, followed by a radical increase in the stringency of the regulations. The last retro-fit of a precipitator took place at Lewes in 1980, a year before the plant shut down.

Notes

Note 1. Leslie Judah Solley was Labour MP for Thurrock, and had 70.0% of the vote at the 1945 General Election.

Note 2. There were also contributions to the local dust burden from Cliffe (on the Thames) and Rochester and Martin Earles (on the Medway).

Note 3. The limited data on this was provided by the Alkali Inspectorate, and was probably mainly derived from the results of a limited number of deposition gauges around the area, although data from exhaust duct flowrates was becoming available after the war. The “area in question” is undefined. Does he mean the whole of the Thurrock constituency? Or just the urban areas close to the river? Or both banks? Based on actual knowledge of kiln operations, the total stack dust emissions from the eight Thames plants can be estimated at around 4500 tons per month. The constituency at the time had an area of 59.88 square miles, so on this broad basis the number quoted was of the right order of magnitude. But see the discussion above.

Note 4. As pointed out later by the minister, the health effects of the dust, insofar as they were known at all, were thought to be minimal, but the lack of firm knowledge could be used to raise a “fear of the unknown”. Most of the constituents of the dust were physiologically-benign calcite, aluminosilicates and clinker minerals, making it purely a “nuisance-dust”. However, the dust also contained quartz (probably around 2-6%) and heavy metals. Metals such as cadmium, mercury, thallium and lead, which concentrated in the dust, would be confined to the ultra-fine fractions of the dust, and would probably never reach ground level in the locality. As a “nuisance-dust”, it clung tenaciously to all surfaces, particularly paintwork, and at high concentrations, stunted plant life by coating its leaf-surfaces. The practise, which became quite common, of handing out bottles of acid to clean surfaces, was probably more hazardous than the original dust.

Note 5. Arthur Charles Davis, Portland Cement: 3rd Ed, Concrete Publications Ltd, 1934.

Note 6. Frederick Cottrell patented his electrostatic precipitator in 1907, initially to remove liquid mist from wet gases, but the method was first applied to a cement kiln at the Crestmore (California) plant of the Riverside Cement Company in 1911. The first in the UK was at Wishaw in 1928, followed by Billingham (1930) and Johnsons (1933).

Note 7. Hansard misheard this as “Aston”.

Note 8. Kiln 2 had in fact been shut down in the previous year – maybe they didn’t tell the Alkali Inspector. Kiln 1 was shut down a few months later, and kiln 3 a few years after. All these were replaced with much larger kilns equipped with precipitators. By contrast with Tunnel, Bevans across the river had no precipitators at all, and Kent had only cyclones. Tunnel, as the biggest plant, naturally drew attention, but the neighbouring Metropolitan plant was probably the worst polluter - it had calcinators, which generated much more dust than ordinary wet process kilns, and had only cyclones to clean the exhaust gas.

Note 9. Norman Noel Dodds was Labour MP for Dartford, and had 68.4% of the vote at the 1945 General Election. Dartford actually contained no cement plants. The Kent, Johnsons and Swanscombe plants were, oddly, in the Chislehurst constituency, and George Wallace, its Labour MP, did not speak in the debate. Nor did Garry Allighan, Labour MP for Gravesend, in which Bevans and Cliffe were situated.

Note 10. Lavington, Wilts is about 13 km east of the site of the proposed Westbury plant. This appears to be an error - he is probably referring to the Laverton Institute, Westbury, where public enquiries into the plan for the Westbury plant were held, beginning in 1946. Subsequently, the development fell within the control of the 1947 Planning Act, slowing progress considerably; the plant did not start until 1962. All the cement companies moaned incessantly about the delays brought about by the act, but in view of the facts in this article, planning authorities had every right to be fearful about the arrival of the cement industry in their areas.

Note 11. Lewis John Edwards was Labour MP for Blackburn, and had 52.0% of the vote at the 1945 General Election. The Alkali Inspectorate fell within the purview of the Ministry of Health.

Note 12. The minister was conveying the consensus of several medical surveys that had taken place over the years. The importance of breathable quartz had not emerged at that stage.

Note 13. The minister got his data from the Southeast Region Alkali Inspector, whose remit covered a wider area. The annual capacity of the eight Thames plants at that time was around 4 million tons.

Note 14. As is almost always the case with such superlatives, the speaker lacks the knowledge to make such a statement. There were several such concentrations of cement production around the world.

Note 15. Just what means were "practicable" remained open to argument. The form of words effectively excluded the shutting down of plants that failed to comply - they would, at best, "do all they could", which for a small impoverished plant might, in fact, be nothing.

Note 16. To the industry's dismay, cement production was brought within the scope of the Alkali Act in 1881, but reports of the inspectors had only advisory effect until 1935.

Note 17. The Alkali Inspectorate had powers to issue regulations, and in 1935, regulations specific to cement plants were introduced. This allowed them to insist that brand new plant should have "best practicable" dust control from the outset, and that, where a plant was to be extended, retrofitting of existing plant should take place. Nevertheless, these powers were not consistently exercised.

Note 18. The question of the supply of steel is a major point of the debate. The industry had begun to blame their poor environmental performance on lack of steel in 1946. The steel industry, although not nationalised until 1949, came under control of the Ministry of Supply in 1940. The excuse that lack of steel prevented the cement industry from installing dust control equipment was rightly seen as specious, as discussed above. This point is proved by the fact that, during the 1950s, when steel supply was good, the industry remained reluctant to install good dust control. To a large extent, the cement industry's complaints about post-war supply of steel - and coal - were politically motivated. Industry leaders were explicitly blaming "socialism" for all their problems.

Note 19. Denis Nowell Pritt was ILP MP for Hammersmith North, and had 63.8% of the vote at the 1945 General Election.

Note 20. Let me tell you a story. In 1978, Ken Bezant had just arrived as the Exterminating Angel plant manager at Humber. He was concerned about the very high dust losses (particularly on SRPC production) on kilns 1 and 2, which limited production and caused major quality problems, and interviewed me about it. Since I could provide no suggestions for improvement, he suggested that I should consult with Peter Walker. In retrospect, I wonder if he suggested this as an elaborate joke. With some trepidation - after all, people like me did not talk to such God-like eminences - I picked up the phone and dialled his number. I explained the situation. On OPC the kilns lost 15% dust. On SRPC, 20-25%. He registered considerable surprise. He asked "do you measure moisture contents in the chain system?" "Yes, of course, regularly!" "What is the typical moisture content of the material leaving the chains?" Picking myself up off the floor, I reply "well, we've never measured it. But we have measured its temperature - it's 650°C!" He says "Ah, well that's your problem. It should contain 5-10% moisture. Try increasing the slurry feed rate." This was one of those scales-from-my-eyes moments. So much for Peter Walker.

Note 21. Every plant manager (at least in Blue Circle) had a well-stocked drinks cabinet to lubricate his discussions with visiting Inspectors, and the latter often departed with bottles under their arm. On one memorable occasion, when I took the Inspector around a plant (I won't say which) after being softened up by the plant manager, he said "If I'd known it would be this bad, I'd have asked for a case!"

Note 22. .