Preliminary Design Considerations

FRED and OSCAR have been tasked with jobs that require them to be outside of a laboratory environment. Our discussions with industry experts emphasized the need to design a system that minimized the chance of any bacteria escaping into the environment. Despite our belief that due to the increased metabolic load FRED and OSCAR are undertaking they would not be able to outcompete any native bacteria, we took these concerns to heart when we designed our project. We have designed multiple layers of controls for each system, utilizing both biological and physical controls.

Physical: The first line of defense

The best way to prevent FRED and OSCAR from spreading into the environment is to make sure that they can't get to it. As such both our bioreactor and biosensor prototypes involve isolating the bacteria in closed systems. In our biosensor we seal the tubes with a one way valve with FRED trapped inside. The tailings sample is added through the one way valve and then when the testing is done the cap is twisted slightly to release bleach into the sealed system. After the bleach is added the tube is disposed of in a safe manner.

OSCAR presents more of a challenge, as he needs to remain in one place for an extended period of time to perform his tasks. For this we have created a bioreactor house for him. In this sealed system filtered air is bubbled in to keep oxygen levels optimal while a HEPA filter is used to screen air coming out. To extract any hydrocarbons from the reactor a belt skimmer is used that selectively picks up oil while leaving bacteria behind. When the oil is seperated from the belt skimmer it is exposed to UV to kill any bacteria, and then is placed into a fractional distillator that heats to 400°C to seperate the hydrocarbons from each other.

Biological: Preparing for the worst