S Block Heroes – Experiences of a Graduate Engineer
In 1974 Monsanto hired 4 graduate chemical engineers at their West Footscray plant, following a similar number in the previous year, in order to allow for existing plant supervisors to be moved onto the start-up team for a 100,000 tonne/y vertically integrated styrene monomer plant planned for start-up in 1977.
I shared an office with 2 other chemical engineers with 1 or 2 years’ experience and all of whom were assigned to the polystyrene plants in ‘S’ Block and were known as the ‘S Block Heroes’ due to an atmosphere of frenetic endeavour to reduce batch cycle times, improve yields and troubleshoot the many inevitable variabilities of batch processes.
We also got up to a range of other activities after work (or sometimes commencing a bit before quitting time) including playing cards and other board games and visiting the local pub on the way home on Friday afternoons.
On my first day at West Footscray I was given a list of projects by my supervisor and it was with a degree of excitement that I shared them with my office buddies, only to have that dashed by their dismissive attitude to “those old chestnuts forget about them”. They promptly took me on a tour of S Block and in particular the Dept 81 control room for introductions to the ‘Flying Dutchman’, Stan and the other plant operators and process foremen, who would become part of my family over the next 3 years.
My first job was to reduce batch charging time. This was real chemical engineering and my study applying Bernoulli’s equation to the styrene charge pump piping network determined that by increasing the charge pump discharge line size from 2” to 3” we could reduce charging time from 20 to 10 minutes without overloading the pump motor, providing the savings for project justification.
At a department meeting I confidently commenced to explain the benefits of the piping replacement, when senior process engineer Bill interrupted abruptly with the words ‘Won’t work, pumps can’t pump more, waste of money’. I was dumbfounded, immediately thinking that I’d made a fundamental mistake in my calculations when I happened to look up at my office buddies, who were thrusting an imaginary microphone in Bill’s face, while rolling an imaginary video camera and bursting with laughter.
Bill didn’t see the funny side of the situation and remained sceptical however, the project was approved and went on to justify its cost of implementation. There was one small problem, however with the new larger piping system which was leaking of styrene monomer from the oval meter flanges following shut-off of the actuated kettle charge valve at the end of charging.
On investigation of this apparent high pressure in the charge pipe manifold it was found that the cause was the new 3” check valve, which unlike its 2” predecessor provided a tight seal against reverse flow, resulting in thermal overpressure of the blocked-in piping segment full of incompressible styrene monomer as the temperature rose during the day. A solution was to drill a 3mm diameter hole in the check valve flapper preventing development of high pressure and oval meter leakage.