CeBER Research Day 2012: my presentation

09 Oct 2012 Comments 0

I made this prezi for the annual, most nerve-racking event of the year – I can argue complex matters with men and kings alike, but the place I am supposed to feel safest leaves my voice shaking and my hands trembling. This prezi still lacks detail, I hope to flesh it out with the next report, but I also think it is a nice overview of where I am…

The online version of the prezi can be found here.

Survival of the Fittingest – 22 August 2012


At last year’s research day, held at the Atlantic Imbizo, on 30 March 2011, I stated that what I was trying to do in the lab was fundamentally not transferable to the real world. I ended with this point: “This talk was horribly generic, an indication of the chaos and search for meaning in every one of the areas in my life. But I cannot get away from the conviction that these areas have to be addressed as a unit. After 4 years, I don’t know how to do that, but I won’t stop trying.”

Then Prof Noakes presented after me about the value of coaches (or academic supervisors), trust, self-belief (which I’m not good at, at all) and then said ‘the lady that just spoke, will make it because she said she would’. Those were words I really needed to hear. He said ‘How do you know how good you are if nobody tells you?’ and noted that this giving of affirmation is against our culture.


Last year’s research day was two weeks before our first TEDxCapeTown event, an immensely personal experience. We’ve just had our second TEDxCapeTown event, where both Tim and Sue [Harrison, my supervisor] spoke.

The reason why I mention TEDxCapeTown, an independently organised TED event, is that “TED forces experts to make their lives’ work comprehensible to the masses, and consequentially captures the attention of a much broader audience. It’s a win win that’s worth replicating.” – I quote Lexi Lewton.


After that day, after TEDxCapeTown, I dropped everything I ever knew, and dove headlong into shit. Figuratively, but I think I might literally do it by mistake soon, because I’m now on site at the Athlone sewage works, a 100+ ML/day plant, to me, an unfathomable volume and flowrate of fluid.

My life is still in chaos, possibly more so than before, because it is at a much bigger scale. But now, there is meaning.


I started the project because I want to produce a polymer, to change a small part of the polymer industry.But now the PhD has become an exercise in how to address various scales of issues as a unit.


Let me show you my thinking:

The concept of a wastewater biorefinery is built around the overarching ability to function in the face of significant infrastructural limitations, and, through its operation, improve these limitations.”


It has a dual objective: To produce a valuable bioproduct while improving the wastestream used to produce it. In order to achieve this, we need to combine aspects of environmental and industrial biotechnology.

Environmental Biotechnology is characterised by its desire to turn waste harmless, to minimise environmental burden.


From discussions I’ve had with people in the field who are using environmental biotech for beneficiation, for example waste to biogas, this field seems to have a strong developmental focus, and what I call blind altruism. The solutions are largely targeted AT the people and environment, not WITH them, and there is no sustainable business model.

Industrial biotechnology on the other hand strikes me as excessively capitalist, selfish. It is a blind chase for profit at the expense of the bigger picture, and often just a growing bubble – look at how the biofuels industry collapsed. The industry has suffered from investors losing trust in the promise of biotech, and most players are struggling to get investment, and battling to scale.


Where environmental biotech is a soft, accommodative field getting caught up in trying to incorporate everything, please everyone and ‘save the world’, industrial biotech suffers from being too narrow minded. For now these are just my opinions, and they are definitely not applicable in every part of the two fields, but I’m willing to be quoted on them, certainly in the context of organic waste management.

Fortunately I’m not alone in trying to combine these mindsets – there are significant driving forces bringing these different mindsets closer together, starting a conversation. These include climate change, greater exploitation of resources, which are themselves of poorer quality. See as example the reduction of soil fertility and agricultural productivity.


The tensions we see arising now is best described by Alan Brent’s quote on Industrial Ecology: “industrial ecology … integrates multiple, mutually exclusive ontologies, and is thus conceptually complex in ways that are new and particularly challenging” (Brent et al 2008). These tensions inform the organisational institutional constraints, they define the process and in turn this informs the technology, whether it will be adapted.

Technology is important, because without it, what you are trying to do is impossible. But we generally place waaaayyyyy too much emphasis on technology though. The process and the way things fit together MUST inform how the technology works. Previously I called this ‘Design for Down-Stream Processing (DSP)’, but now I believe that it goes far wider than this.

One needs to start with positioning your project in the big picture, and see how it fits, to a greater or lesser extent. I believe that even if you are doing fundamental, abstract research, you need to spend a little bit of time on this. An applied engineer like me spends most of her time on this. Understanding the big picture informs every decision you take on the micro scale, and makes it possible for others to create valuable partnerships with you. It ensures that you don’t inadvertently exclude people by design.

One thing I’ve noticed so far is the dialogue around sanitation.’Pro-poor sanitation’, as opposed to ‘appropriate technology’ illustrates ways of thinking that made me do a lot of thinking around western ways of management, and patriarchy. So I’m now finding my feminist self, giving a whole new meaning to being ‘full of shit’. This is not doing my relationships any favours.


Moving towards a particular process, on a full plant scale.

Early on in the project I had to face a lot of criticism about the priorities of a wastewater treatment works. I had to continuously defend the ‘safe effluent’ as top priority. I just could not manage to create a product and guarantee that the effluent will be safe for discharge at the end. This is why a process is so important – now I can include a polishing step, that adds value in its own right, to make sure the water gets clean. I can get people to think beyond their fear of unsafe discharge because there is an additional step that ensures this. I have to design the technology, however, to make sure that I don’t compromise the next step.


At the same time, having an earlier step that takes my unit process into account, not only makes my process more resilient, but may even provide energy that makes my process more cost effective. In this way the units ‘look out for each other’, and improve each other’s operation.


OK, so now that I am comfortable that there is a need, and a space and value for the unit process that can produce my polymer, and that my unit process will not damage the area around it, let’s focus on the technology itself.


I am working with wastewater, so many of the assumptions around conventional biotech does not apply. The fluid is very dilute, so sterilising for the low yields is not appropriate. Instead of the best organism, with the highest yield, we need to instead work with the organisms most capable of surviving in these conditions, build the reactors that best fit the system while giving the organisms a competitive advantage, while allowing for the most appropriate product recovery. It becomes about being the most responsive to each other, being most fitting, and not being the best. It’s a rather feminine discussion, don’t you think? All about relationships.

I acknowledge that this is not suitable to all systems or products. In my project, the important points are that I am working with a retained biomass system, and I am only interested in the surface of the biofilm. I looked at what reactor environment bugs are generally happiest in, under the most likely flows and substrate concentrations.

However, having said that, the rest of the biofilm still needs to be considered for nutrient removal. This meant I needed a thicker biofilm. I also looked at how best to get product out of these reactors, so the surface of the biofilm had to be easily accessible. These considerations narrowed my selection to the two reactors I have chosen.

So a quick introduction to my bacterium, ‘Pirelli’ [look at my previous blogpost - 'PhD, a love story, sortof' to see the thinking behind the names]. Pirelli likes growing at the air water interface, which means that the reactors I have chosen is not 100% suitable for it, but we’re working on designing a partially submerged fixed bed reactor, like trickle tower or similar.

Roberta is a hybrid Rotating Biological Contactor (hRBC), with a mesh disk instead of the conventional plastic disk. As we saw in the previous slide, Pirelli can grow on her, but the growth is only limited to the air-water interface. Here she is on site, sporting a variety of bacteria and microorganisms, because we have not started to manipulate the microbial population to select for Pirelli yet. The good think to note here is that the on-site reactor setup supports growth.

Agnes is an aerobic granular sludge (AGS) sequencing batch airlift reactor. She is a bit more temperamental and did not perform well in the lab, but she is also a new technology globally and so we tolerate the learning curve. On site though, she performed better than anticipated and formed granules in 24 hours, when we inoculated her with activated sludge. With both Roberta and Agnes, we are not confident of product location yet, so we can not make definitive predictions on downstream processing (DSP) yet. This is a significant cost component of a process, but we do have a few options to explore, based on what the polymer does in the field.

Agnes working with real sewage. She performs better here because the low substrate concentration (<1g/L) prevents foaming, and the activated sludge is a better consistency than the pure cultures we had in the lab. The settling rate of the sludge is very fast, more than 60cm / minute (I am not an SVI competent person yet!), but the treatment efficiency is still expected to be low, as the active biomass is low. Next steps are to inoculate these with Pirelli, build more reactors to test different configurations, and do sampling, data analysis and microbial population analysis.

In closing, what I have learnt this year, is firstly, to stick to core business. Look after yourself, you don’t need to save the world. You need to decide what you want to do, and then stick to it.

Secondly, while pursuing your own interest, don’t let what you do limit access for the collective interest. Invest in a common language sothat you can talk across industries.

Lastly, and a continuing journey for me, is to consider everything as a conversation around responsibilities more than rights. Life is a balance between Values, Legislation & Incentives. It opens up questions around democracy vs patriarchy, balancing care and justice. It changes how we look at, and talk about, everything.

The greatest value in wastewater biorefineries lies not in the technology or adequate engineering design, but in the connections between people, adequate communication and the willingness to engage.

I don’t fit in here in many ways, but I do want to tell you that you are all amazing, this is a top outfit group, the best in the world, and I’m proud to be part of this group. Thank you.

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