Week 3 - 3D-Modeling the Module

Week 3 primarily concentrated on the shape and design of the algae containment vessel. Fusion 360 provided a user-friendly way of shaping out the design. The dimensions of the vessel can vary depending on the size of the room in which it will be installed. Generally, it will be a hollow system of tubing, consisting of 10 cm diameter plastic piping. The walls of the pipe are of the stock 7.5 mm thickness. The pipe is clear, appears in a rounded, hollow box form. The file is not complete, so we have not uploaded it. We expect to upload it by next week.

The design itself is relatively simple. The pipe is a closed loop, spanning about 40-50 cm width and about 1 m length. There will be a hydro pump installed on the right side of the piping, to keep the algae moving through. On the left side, adjacent to the pump, will be a release to drain the pipes for cleaning. Supports can be manufactured out of cheaper PVC piping, and installed into the wall or the floor according to a customer’s preference.

4/5/16 - Plastic Decision

Group 1
Our module is reliant upon its ability to allow the algae inside to use carbon dioxide and release oxygen. To contain the algae, plastic tubes are needed, but most plastics do not allow for the diffusion of CO2 and O2 (a reactant and a product of photosynthesis respectively). Two solutions to this problem were to either pump in CO2 into the module or find a plastic that would passively diffuse both CO2 and O2.

To save on cost, parts, time, and to allow for a simpler, smaller, and lighter solution it was decided to forego a gas pump and instead research a plastic specifically designed to diffuse the afforementioned gases.

After many hours of searching through multiple webpages, a plastic that fit this description was found: polysulfone. It can withstand household temperature ranges, the pressure exerted by the water, and the pH of the culture.

Polysulfone resin can be purchased at a price of $1,150/ 25 kg (55.1 lbs), or roughly $46/kg ($20/lb).

4/7/16 - Algae Decision

Group 1
During lab today, the group narrowed down the list of feasible algae candidates. As of now, the best algae belong to the genus Chlorella - chosen for its ability to live in freshwater, its relatively fast reproduction rate, because it does not form mats or strands when growing, and for its high photosynthetic efficiency.

Research needs to be done to determine which species of Chlorella is the best choice to grow in the culture. The noted species are Chlorella vulgaris, Chlorella pyrenoidosa, and Chlorella sorokiniana.