Hello MNM readers!

My IFRF story starts with an interview in May 1978.  I had just been awarded my doctorate in fluid mechanics and heat transfer and was enjoying a holiday near Cannes during film festival week when I was instructed by L’Air Liquide to fly to IJmuiden for a meeting at IFRF.  In those days research investigators weren’t employed directly by IFRF but were seconded to the Research Station for three years by an IFRF member organisation.  In my case, L’Air Liquide had short-listed me as a potential candidate and the trip to IJmuiden was the final decisive step, so I was keen to learn about IFRF and win the job.

What a contrast from the sunny beaches and rarefied atmosphere of Cannes to arrive amongst the smoking chimney-stacks of the Hoogovens steelworks!  When the taxi driver dropped me at  a shabby-looking, wooden prefab, I told him he was mistaken – he pointed at a small sign that read ‘IVO’ (the Dutch acronym for International Flame Research) and drove off.  My first impression was not good but the rest of that day – and the next five years – were very different!

I met with Roy Payne (Scientific Manager), Sigfrid Michelfelder (Director) and a very international group of investigators from Japan, Germany, Italy, the Netherlands and France.  Our discussions were extremely stimulating and confirmed that the combination of high-level science and practical industrial application of the research, as well as the truly international nature of the research team and the industrial members, would give me a unique learning opportunity in a challenging environment – exactly what I was looking for after three years of academic research.  I flew back to Nice having decided to take the job and to share my enthusiasm with my wife (who was also ready to live in a different country), and we made what proved to be one of the most important decisions of  our working lives that very night.

On joining IFRF in July 1978, my first job was to manage a US EPA/EERC (California) contract on the effect of atomizer design and droplet size on NO_x formation in oil-fired burners.  For this contract, IFRF had bought the first, recently-developed, Malvern laser scattering analyser.  We investigated different atomizers and showed that although droplet size distribution were very different and had an impact on NO_x and other flame properties, there was no simple relationship and that droplet trajectories and velocities in the near-field of the burner ought to be considered.  This work was published at the 3^rdEPA Symposium on Stationary Source Combustion in Los Angeles in 1979, allowing me an unforgettable first trip to the USA and an inspiring exposure to the American way of conducting research:

• The control of pollutant formation in fuel oil flames; the influence of oil properties and spray characteristics (England, Heap, Horton, Pershing, Flament), EPA, 3^rd Symp. on Stationary Source Combustion, March 1979
• Effects of fuel properties and atomization parameters on NO_x control for heavy fuel fired package boilers (Flament, Payne) – IFRF Doc. No. F 09/a/20, 1979

This project was one amongst several driven by the strong interest of industry and governments for NO_x reduction from oil, coal and gas flames.  Since funding from the European Coal and Steel Community had declined and members’ contributions only accounted for about 25% of IFRF’s annual budget, we had to seek direct industry and governmental research funding in order to sustain the Research Station.  For instance, the ‘Air Pollution’ trials series (AP-6 to AP-11) were supported by the Dutch government and aimed at better understanding the effect of burner designs, scaling, confinement, firing density and boundary conditions on NO_x emissions from boiler or industrial furnace burners burning oil, coal or gas.  This work is described in the following paper:

• Recent activities of the IFRF Research Station in the field of pollution control in industrial combustion systems (Akiyama, Flament, Witkamp), VDI-BerichteNo. 423, 1981

Experimental trials were often conducted in IFRF’s refractory-lined Number 1 Furnace which had huge thermal inertia, necessitating round-the-clock operation and measurements for extended periods of up to three weeks.

For these experimental campaigns one investigator was nominated ‘trial leader’, managing the project, with two or three other ‘shift leaders’ managing the operators and measuring technicians during 8-hour morning, afternoon or night shifts (week-ends included).  During the AP series trials, I worked as a shift leader, later taking on the trial leader role.  Needless to say this work pattern created a strong team spirit – we felt both empowered and responsible, and shared our failures and successes.

As part of the research undertaken during my five years assignment to IFRF, several proprietary industrial low-NO_x burners were also tested and some fundamental studies of NO_x formation in simple long coal flames were also conducted for EPA.  For more information, please see the following IFRF document from the Archive:

• Detailed measurements of long pulverized coal flames for the characterization of pollutant formation (Michel, Payne) – IFRF Doc.No. F 09/a/23, 1980

Together with such industrial contract work, IFRF also conducted members’ research, elaborated by the Programme Executive in discussion with the so-called Technical Panels.  The main topic at this time was scaling of combustion systems.

The ‘Oil Burner’ (OB) trials (O-18 to O-19) were designed for detailed comparison of flames from similar gas- and oil-fired burners at different scales ranging from 0.6MW_th to 33MW_th in collaboration with the UK’s Central Electricity Generating Board (CEGB), which was conducting the large scale burners while IFRF tested at the 0.6-2.3MW_th size.  See:

• Investigation into the scaling of combustion systems: O-18 and O-19 investigations (Salvi, Payne) – IFRF Doc. No. F 31/a/52, 1981

Although the experiments went well and produced very useful data, they clearly showed that simple scaling rules could not be derived – particularly for oil flames swirling burners –  because of the importance of residence time for droplet evaporation and the complex interaction between spray and swirling flow at the root of the burner.  This encouraged us to initiate the members-funded ‘Near-Field Aerodynamics’ (NFA) programme in 1983.  This programme continued until 1990 and generated a wealth of new information and the concept of the ‘aerodynamically air-staged’ low-NO_x burner (AASB).  The NFA programme is described in the following Archive paper:

• Background and programme outline for the IFRF burner near-field aerodynamics project (Bortz) – IFRF Doc. No. G 14/a/2, 1983

In 1980, another strong line of research was launched thanks to a very ambitious contract with Steinmüller of Germany, with the financial support of the German Federal Ministry of Environment.  This involved the injection of calcium-based sorbents into pulverised coal flames for simple, low-cost in situ SO₂ capture.  While not a new idea, the development of staged combustion for NO_x reduction had created different temperature fields believed to be more favourable to such a process.  The first experimental campaign, conducted in 1980, proved very promising and this work generated strong interest from various parties in Europe and the USA.  IFRF members decided to spend some internal money to improve the fundamental understanding of calcination and sulphation of calcium hydrates and carbonates in an isothermal plug flow reactor (IPFR) and, simultaneously, run practical experiments.  Meanwhile, after some specific trials in Number 1 Furnace, Charbonnages de France decided to implement this technology on a new 700MW_e coal-fired power station.  See the following paper for more information:

• Reduction of SO₂ emissions from a coal-fired power station by direct injection of calcium sorbents in furnace (Brice, Chelu, Flament, Manhaval, Vandycke), EPA/EPRI 1^st Joint Symp. on Dry SO₂ and Simultaneous SO₂/NO_x Control Technologies, San Diego, November 1984

IFRF’s work on direct SO₂ capture continued until the late 1980s when it became clear that in spite of its good cost efficiency, this process would not be able to meet the stricter regulations being implemented worldwide, and which necessitated flue gas desulphurisation (FGD) systems being deployed.

From a personal point of view, the first SO₂ trial for Steinmüller was the last project that I managed as, in Summer 1980, Roy Payne left IFRF for a position at EERC in California and I was offered the job of Scientific Manager.  This was quite a challenging – I was 29 and had to take over managing of a team of seven investigators, some of whom were new to IFRF, with others joining soon after.  Furthermore, taking over from Roy was a real challenge for me.  Having worked very closely with him for two years, I had developed a huge respect for his capacity for work, his sharp yet simple way of understanding complex technical issues, and his people-management skills:  I was not sure that I was up to the task!  However, with support from IFRF’s various panel chairmen, combined with my fellow investigators’ friendly approval, I took the position.

During my three years as Scientific Manager, IFRF continued its ongoing studies.  These included the AP series (up to AP-11) where we studied the effect of coal quality on the behaviour of air-staged combustion with a focus on NO_x and flame properties.  Eleven different coals, ranging from low-volatile bituminous to sub-bituminous coals, were tested and exhibited huge differences in behaviour which we could not explain.  Subsequently, these results led us to build a vertical furnace operating as a plug flow reactor to study nitrogen behaviour and its conversion to NO_x during coal combustion under more controlled conditions.  For more information on this research, please see:

• Direct reduction of sulphur dioxide emission with pulverized coal firing using calcium based sorbents (Flament, Parodi), VDI-Berichte No. 498, 1983
• Recent IFRF studies upon the reduction of NO_x and SO₂ emissions from pulverized coal flames using staged mixing burners (Flament, Phelan), in Air Pollution by Nitrogen Oxides(edited by Schneider and Grant), Elsevier, 1982

A key task of the Scientific Manager was to elaborate proposals for contract research work.  Indeed, during this period the Research Station needed research contracts with a value of around three times the funding being contributed by IFRF members in order to balance our budget.  The costs associated with running Number 1 Furnace for a week of experiments meant that we had to sell the equivalent of 20 weeks of such experiments every year!  I recall having to write 15 contract research proposals during my last year at IJmuiden, and not all of them were successful.

Fortunately, oil prices had gone sky high at that time and many industries were very interested in switching from oil to any other fuel.  As a consequence, IFRF won several industrial research contracts on this issue – and some of these were of considerable technical interest.  For example, Hoogovens contracted IFRF to combust pulverized coal under conditions simulating a blast furnace environment, requiring us to fit a real blast furnace tuyère to Number 1 Furnace and operate at a combustion air temperature of 1200°C.  While the ‘scientific dimension’ was not always present, such contract work did offer other benefits, including helping IFRF to survive financially and the building/procurement of valuable new equipment for the Research Station.  It also brought to those involved in the work, including myself, a unique opportunity to acquire wide-ranging practical experience of handling and burning almost anything in any furnace conditions, thus becoming real combustion engineers!

However, undertaking such short-term, practically-oriented, contract work was not what IFRF had been established for, and we were very aware that more long-term financing had to be secured in order to avoid IFRF’s operations having to be scaled down.  This imperative encouraged us to seek support from the International Energy Agency (IEA), which was seeking to undertake combustion research.  In May 1983, shortly before I left, IFRF took part in a decisive meeting in the USA at which the key elements of an IEA research programme on coal combustion sciences were elaborated.  An agreement was signed in 1984, bringing IFRF generous financial support and enabling the staff to focus more on combustion research and less on income generation from contract research.

Looking back on my time at IFRF some forty years later, I can say that my five years’ experience there was the most thrilling and decisive part of my professional career.  The combination of a unique multi-cultural team, and collaboration with the best academics and premium players in industry was challenging and required a tremendous amount of work.  The learning-curve was extremely steep but very rewarding.  I have never learnt as much as during those five years, and this experience proved to be an outstanding asset for the rest of my career.

Gérard Flament

[Ed. – thank you, Gérard, for sharing what a formative experience IFRF was in your professional career.]