Problem: The first UASB reactor is barely producing any biogas. This is a sign that microbes in the reactor are not working to their full potential (the reactor and gas bag have already been checked for leakage). Literature review suggests that the performance of the reactor could be improved by increasing the temperature of the water.
Potential Solution: Apply heat tape to the reactor to warm the water. This tape could possibly be wrapped around the bottom half of the reactor, or around the clear flex influent tubing (connected to the peristaltic pump). Wrapping the tape around the influent tubing, rather than the reactor itself, would promote more even heating due to a large surface area. Connect a temperature probe near the effluent of the reactor, and use ProCoDa to take constant temperature measurements. Used with a relay box, ProCoDa can turn the heat tape on or off automatically, depending on the temperature of the effluent water.
Questions to Answer:
What is heat tape? How does it work? How do you attach it? How do the different types of heat tape differ from each other?
What is the range of temperatures that a UASB can successfully operate at? Is there any equation that could help us predict the optimum temperature for our reactor? (We may already have these answers in our literature review from last semester. Look there first)
What is the ambient temperature of the room where the reactor is located, and what is the influent temperature of the water coming from the wastewater plant?
How much energy will be lost to heating the room, rather than heating the water?
How much energy is needed to heat the water to the desired temperature, with and without taking heat loss into account? (Use basic thermo and definition of specific heat capacity)
What types of heat tape can be covered with insulation safely?
Are both the PVC pipe and the clear flex influent tubing compatible with the temperature ranges used by the heat tape?
Is the heat tape flexible enough that it could be wrapped around the clear flex influent tubing?
To connect the temperature probe to the reactor, we will need to drill a small hole/port and create a water-tight seal. Where is the best location on the reactor to do this (we want the effluent temperature)? The temperature probe already has a mechanism for such a connection in between the probe itself and the 'handle' (check out the temperature probe sitting on our lab bench).
The cord on the temperature probe is not long enough to reach our ProCoDa box. How can we make it longer? Are there extension cords with the correct type of connections?
Will the temperature probe need to be cleaned? Will the accumulation of gunk on the probe prevent it from working properly?
Problem: The first UASB reactor is barely producing any biogas. This is a sign that microbes in the reactor are not working to their full potential (the reactor and gas bag have already been checked for leakage). Literature review suggests that the performance of the reactor could be improved by increasing the temperature of the water.
Potential Solution: Apply heat tape to the reactor to warm the water. This tape could possibly be wrapped around the bottom half of the reactor, or around the clear flex influent tubing (connected to the peristaltic pump). Wrapping the tape around the influent tubing, rather than the reactor itself, would promote more even heating due to a large surface area. Connect a temperature probe near the effluent of the reactor, and use ProCoDa to take constant temperature measurements. Used with a relay box, ProCoDa can turn the heat tape on or off automatically, depending on the temperature of the effluent water.
Questions to Answer: