From the 1970s to today: A view on environmental progress
David Owen reflects on his career in chemistry, exploring how initially environmental chemistry was primarily concerned with the development of control techniques to comply with emerging environmental legislation.
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About the author
David Owen has an organic chemistry background; his first degree was from Liverpool University. He worked with Lucas in Birmingham as a development chemist in the motor vehicle battery industry and subsequently received a PhD in organo-fluorine chemistry from Birmingham University. After working for British Steel for three years, he joined Betz Laboratories, an American water treatment company with a spread of interests, set up the Irish operation and resided in Ireland for four years before setting up his own business specialising in wastewater management and its chemistries. Specialist areas included paper chemistry and refinery equipment decontamination during turnaround maintenance. He later established a new chemical company, marketed towards waste management in the oil industry (drilling fluid management) and in refinery process waste streams. He continues to consult on specific industrial problems and serves on the RSC ECG committee. |
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I spent my early working years in industry working at an American company specialising in water and process chemistry. Their target market was large process industries in continuous operation: hydrocarbon processing (refining); exploration (downhole); chemical plants (e.g. ammonia or urea, monomers for plastics such as ethylene and styrene); steel; mining (especially coal); metal industry (e.g. bauxite purification and aluminium production); and paper. Other miscellaneous industries included fibre production from cellulose or man-made raw materials. This work gave me precious expertise in a variety of industry practices and processes; I will discuss some of them here. After understanding utilities and processes, which were the beating heart of their operations, more detailed analyses turned to corrosion control in cooling water, boiler-water treatments to ensure optimum heat transfer and cleanliness of the water and equipment furnaces.”
Water industry
In the late 70s, the major concern was environmental compliance, especially effluent waters. Suspended solids, oil in water, COD (chemical oxygen demand) and chemicals became the main source of anxiety. At the time, it was common to use chromate-based corrosion inhibitors in large cooling water systems. The reason? Because they worked well. The wastewater then went down the drain untreated. Some plants were using several tonnes of chromate per year. This was the substance that caused cancers in California, as depicted in the film Erin Brockovich, a landmark case in environmental law. Aided by technology advances, chromate was phased out in the mid-80s. Indeed, many substances used for various industrial applications were either banned outright or substituted in the 80s. For example, hydrazine was used as an oxygen scavenger in high pressure boilers. The material was shown to be mutagenic and new technology was introduced to prevent exposure.”
In the late 70s, the major concern was environmental compliance, especially effluent waters. Suspended solids, oil in water, COD (chemical oxygen demand) and chemicals became the main source of anxiety. At the time, it was common to use chromate-based corrosion inhibitors in large cooling water systems. The reason? Because they worked well. The wastewater then went down the drain untreated. Some plants were using several tonnes of chromate per year. This was the substance that caused cancers in California, as depicted in the film Erin Brockovich, a landmark case in environmental law. Aided by technology advances, chromate was phased out in the mid-80s. Indeed, many substances used for various industrial applications were either banned outright or substituted in the 80s. For example, hydrazine was used as an oxygen scavenger in high pressure boilers. The material was shown to be mutagenic and new technology was introduced to prevent exposure.”
Atmospheric chemistry
During my PhD, studies into organo-fluorine chemistry, the hole in the ozone layer finding was discovered. Chlorofluorocarbons (CFCs) were blamed, and the Montreal Protocol ended their manufacture in the West. China continued to manufacture CFCs long after replacements were found. Fluorine chemistry was seen as the sole bad actor, although its products had been in existence for some time as aerosol propellants and as refrigerant gases.
During my PhD, studies into organo-fluorine chemistry, the hole in the ozone layer finding was discovered. Chlorofluorocarbons (CFCs) were blamed, and the Montreal Protocol ended their manufacture in the West. China continued to manufacture CFCs long after replacements were found. Fluorine chemistry was seen as the sole bad actor, although its products had been in existence for some time as aerosol propellants and as refrigerant gases.
Oil industry
At Birmingham University, one of my lecturers was seriously concerned about lead in petrol as an octane improver. He would tell anyone who would listen about the evils of the substance. He was a respected academic, but most people simply listened politely and shrugged.
In the UK, there was a pecking order between industries. Usually, the oil and petrochemical industries would clean up their act first with the installation of new effluent plants to deal with free oil in water, suspended solids and sometimes biological oxidation of pollutants in an oxidation ditch. Clean-up in other industries would follow. There was an industry based in Ellesmere Port next to the Shell petrochemical plant, that manufactured tetraethyl lead (TEL). Prior to being was phased out in 1999, it had been responsible for 74% of UK lead emissions from petrol. After phase-out, the contribution was just 1%. The manufacturer moved into new products, and seeing the redundant equipment from the manufacturing of TEL, the sense of ‘why did it take so long’ was overwhelming.
At Birmingham University, one of my lecturers was seriously concerned about lead in petrol as an octane improver. He would tell anyone who would listen about the evils of the substance. He was a respected academic, but most people simply listened politely and shrugged.
In the UK, there was a pecking order between industries. Usually, the oil and petrochemical industries would clean up their act first with the installation of new effluent plants to deal with free oil in water, suspended solids and sometimes biological oxidation of pollutants in an oxidation ditch. Clean-up in other industries would follow. There was an industry based in Ellesmere Port next to the Shell petrochemical plant, that manufactured tetraethyl lead (TEL). Prior to being was phased out in 1999, it had been responsible for 74% of UK lead emissions from petrol. After phase-out, the contribution was just 1%. The manufacturer moved into new products, and seeing the redundant equipment from the manufacturing of TEL, the sense of ‘why did it take so long’ was overwhelming.
Steel industry
The steel industry was large, with five major sites operating blast furnaces and steel converter plants called BOS (basic oxygen steelmaking). This was known as the “heavy end”. The making of steel required a large amount of metallurgical grade carbon in the form of coke.
A coke oven was an ecological nightmare, the coal was converted to coke by dry distillation of crushed coal at >1100°C. The gas produced was extremely crude and consisted of hydrogen, carbon monoxide, aromatics such as benzene, toluene and xylene (BTX), and it was rich in ammonia and tar. Other contaminants were cyanide and sulphide. The odour was unique and enveloped the local area. A by-product plant attached to each coke oven cooled and cleaned the gas to remove some of the contaminants. Huge steam plumes developed when these plants quenched the red-hot coke underwater. The clean gas was used to fire the ovens , with the remaining used to heat processes in the steel mill. Each of the operations were large units on vast sites. The main issues were fouling in off gas mains and equipment along with wastewater quality. Typical plants could produce about 40,000 tonnes of coke per week.
Most of this activity came to an end with the sale of the British Steel Corporation (BSC). Once in private hands, the corporation was downsized, and major steel works closed their “heavy end” forever. At one stage, BSC was making about 15 million tonnes of steel per year. The tonnage has been reduced with the closure of the heavy ends .
The steel industry was large, with five major sites operating blast furnaces and steel converter plants called BOS (basic oxygen steelmaking). This was known as the “heavy end”. The making of steel required a large amount of metallurgical grade carbon in the form of coke.
A coke oven was an ecological nightmare, the coal was converted to coke by dry distillation of crushed coal at >1100°C. The gas produced was extremely crude and consisted of hydrogen, carbon monoxide, aromatics such as benzene, toluene and xylene (BTX), and it was rich in ammonia and tar. Other contaminants were cyanide and sulphide. The odour was unique and enveloped the local area. A by-product plant attached to each coke oven cooled and cleaned the gas to remove some of the contaminants. Huge steam plumes developed when these plants quenched the red-hot coke underwater. The clean gas was used to fire the ovens , with the remaining used to heat processes in the steel mill. Each of the operations were large units on vast sites. The main issues were fouling in off gas mains and equipment along with wastewater quality. Typical plants could produce about 40,000 tonnes of coke per week.
Most of this activity came to an end with the sale of the British Steel Corporation (BSC). Once in private hands, the corporation was downsized, and major steel works closed their “heavy end” forever. At one stage, BSC was making about 15 million tonnes of steel per year. The tonnage has been reduced with the closure of the heavy ends .
Coal industry
The coal industry existed in most parts of Britain; however, the problems of pollution were particularly severe in South Wales due to the narrow seams and the presence of fine clays near the seams. The excavated coal had to be crushed and washed to provide a clean product. The washeries designed to settle out the polluting clays failed badly and there was a high load of clay discharged to the local rivers. In the late 70s, products became available which caused the clays to floc into larger, settle-able particles. The lagoon systems began to work well, and this type of pollution effectively ceased. Now the problem has disappeared due to closure of all the pits.
The coal industry existed in most parts of Britain; however, the problems of pollution were particularly severe in South Wales due to the narrow seams and the presence of fine clays near the seams. The excavated coal had to be crushed and washed to provide a clean product. The washeries designed to settle out the polluting clays failed badly and there was a high load of clay discharged to the local rivers. In the late 70s, products became available which caused the clays to floc into larger, settle-able particles. The lagoon systems began to work well, and this type of pollution effectively ceased. Now the problem has disappeared due to closure of all the pits.
Paper industry
The paper industry in Britain has had a chequered past. Local production was in three main centres: Kent, Northwest England and Scotland. There were some pulp mills working in the 70s and into the 80s, but the polluting nature of the chemical pulping of raw feedstock (trees) made the environmental compliance impossible. The other main factor was the price of energy; ~ 1 tonne of water is evaporated per tonne of wet laid pulp in the formation of a sheet of paper. The solution was a change in scale of operations and product type.
Recycling plants were devised and commissioned to recover good pulp to make recycled white paper. The removal of ink from used paper became an art form using washing and floatation technologies with special chemical additives to make the plants technologies work. One of the unmentioned wastes from the recycling from pulp to paper is the waste fillers, usually chalk or clay, along with the rejected short fibres and inks. This material represents a large waste stream, typically of the order of several hundred tonnes per day for a typical 300 tonne per day pulp plant on a dry weight basis. It is spread on land as a form of ‘fertiliser’ on farmland local to the mills. There has been no viable alternative route to a product to date although some significant trials at making construction board were carried out.”
The paper industry in Britain has had a chequered past. Local production was in three main centres: Kent, Northwest England and Scotland. There were some pulp mills working in the 70s and into the 80s, but the polluting nature of the chemical pulping of raw feedstock (trees) made the environmental compliance impossible. The other main factor was the price of energy; ~ 1 tonne of water is evaporated per tonne of wet laid pulp in the formation of a sheet of paper. The solution was a change in scale of operations and product type.
Recycling plants were devised and commissioned to recover good pulp to make recycled white paper. The removal of ink from used paper became an art form using washing and floatation technologies with special chemical additives to make the plants technologies work. One of the unmentioned wastes from the recycling from pulp to paper is the waste fillers, usually chalk or clay, along with the rejected short fibres and inks. This material represents a large waste stream, typically of the order of several hundred tonnes per day for a typical 300 tonne per day pulp plant on a dry weight basis. It is spread on land as a form of ‘fertiliser’ on farmland local to the mills. There has been no viable alternative route to a product to date although some significant trials at making construction board were carried out.”
Agricultural industry
Another major pollutant is ammonia. It is estimated that about 75% of all chemical ammonia sources spread on agricultural land (as fertiliser) ends up in rivers and ultimately in the air, where it acts as an air pollutant. The chemical industry has optimised the manufacture of ammonia from atmospheric nitrogen via the Haber process. A typical modern plant can produce 1000 tonnes per day of ammonia and 1200 tonnes per day of urea from a purified natural gas source. The carbon footprint has been reduced but remains large. New technology is emerging to optimise nitrogen in fertiliser, designing them to provide exactly the amount of nitrogen the plant needs.
Another major pollutant is ammonia. It is estimated that about 75% of all chemical ammonia sources spread on agricultural land (as fertiliser) ends up in rivers and ultimately in the air, where it acts as an air pollutant. The chemical industry has optimised the manufacture of ammonia from atmospheric nitrogen via the Haber process. A typical modern plant can produce 1000 tonnes per day of ammonia and 1200 tonnes per day of urea from a purified natural gas source. The carbon footprint has been reduced but remains large. New technology is emerging to optimise nitrogen in fertiliser, designing them to provide exactly the amount of nitrogen the plant needs.
Conclusions
The most polluting industries have closed down in the UK over the last fifty years and been exported to less regulated areas of the planet, driven by politics, legislation, economic factors and consumer action. In the next industrial age, critical raw materials and utility products promise to be the focus.
The most polluting industries have closed down in the UK over the last fifty years and been exported to less regulated areas of the planet, driven by politics, legislation, economic factors and consumer action. In the next industrial age, critical raw materials and utility products promise to be the focus.
Reference
B. Christman, A brief history of environmental law in the UK, Environmental Scientist, November 2013, pp 4-8; env_sci_nov_13.pdf (the-ies.org)
B. Christman, A brief history of environmental law in the UK, Environmental Scientist, November 2013, pp 4-8; env_sci_nov_13.pdf (the-ies.org)
