Chemical and Bioengineering postgraduate personal statement example

Personal statement example

Before each brew at the small brewery where I work, I take a sample from the clean-in-place return line and titrate it to check the caustic strength. If the solution has been diluted by rinse water or weakened by carbon dioxide left in a tank, the clean will not do its job, and a batch of beer can be lost to bacteria weeks later. It is a five-minute task, but it taught me something my degree had only described: a biological process is only as reliable as the engineering around it. I am applying for postgraduate study in chemical and bioengineering because I want to understand that relationship properly, from the behaviour of enzymes and cells to the design of the equipment that keeps them productive.

My undergraduate degree gave me a solid grounding in transport phenomena, thermodynamics, reaction engineering and process control. The modules I found most absorbing were those where these ideas met biology, particularly the treatment of Michaelis-Menten kinetics alongside reactor design. It struck me that an enzyme behaving perfectly in a test tube can perform very differently once it is packed into a column and fed continuously, and that question shaped my final-year project.

For the project I immobilised lactase in calcium alginate beads, packed them into a jacketed glass column and pumped lactose solution through at different flow rates, measuring glucose in the outlet with a colorimetric assay. At low flow rates conversion was high, as expected, but the relationship was not linear, and beads made with a higher alginate concentration gave noticeably lower conversion. Working through the results with my supervisor, I used the Thiele modulus to argue that diffusion inside the larger, denser beads was limiting the reaction rather than the enzyme itself. I also ran the column for six days to track loss of activity, which fell steadily, and I suspect some enzyme leached out as the beads softened. The project was modest in scale, but it showed me how much careful measurement matters: I spent the first fortnight simply making beads of consistent size before any useful data was possible. I achieved a first for the project, and it left me wanting to study immobilisation, mass transfer in biological systems and scale-up in greater depth.

My brewery job has added a practical dimension. I work in the cellar two days a week, logging gravity and temperature during fermentation, transferring beer between tanks and running cleaning cycles. I have no authority over recipes or plant decisions, but I have noticed how much the brewers rely on judgement where measurement is thin, for example estimating yeast health from how vigorously a fermentation starts. That gap between experience and quantitative understanding interests me, and I would like my further study to help close it, whether through better monitoring or better models of fermentation.

Outside work I volunteer at a community bike workshop on Thursday evenings, helping people fix their own bicycles rather than doing it for them. Explaining why a chain slips or a brake drags to someone who has never held a spanner has made me a clearer communicator, and it is a useful reminder that a good fix is one somebody else can maintain. I also enjoy long-distance cycling, which has given me patience for problems that take hours rather than minutes to solve.

I am drawn to postgraduate study because I want the depth to tackle problems in bioprocessing independently: designing systems where enzymes or microorganisms work under conditions that suit both the biology and the plant. I have the core engineering foundation, hands-on laboratory experience and a working knowledge of how a real fermentation process runs day to day. I would bring care with data, steady persistence and a genuine curiosity about why processes behave as they do.