Session: Research Posters

Paper Number: 120046

120046 - Design and Optimization of a Cost-Effective Bioreactor for Biogas Production With Feedback Control System 

This research focuses on the design and development of an economical bioreactor system for efficient biogas production. The biogas production through bioreactors relies on diverse configurations and circuit designs with sensors, which play a crucial role in industry-grade equipment. The dissolved oxygen (DO) sensor, pH sensor, temperature sensor, and agitator motor speed feedback are essential design parameters that form pivotal components of a comprehensive control system. While the DO sensor is to monitor for potential oxygen leaks into the vessel, the remaining sensors control pH regulation, heating control, and the physical motor speed, respectively. The central controllers for this system are an Arduino microcontroller and a standalone proportional-integral-derivative (PID) temperature controller. The Arduino consistently monitors the pH level and implements appropriate corrective measures to maintain the pH within the predefined working range for efficient biogas production. This utilizes a peristaltic pump, this injection method ensures controlled flow, and a three-way solenoid valve allows the pump to prime the lines first, which eliminates potential oxygen exposure to the system. When a solution is required to get the pH back within the parameters, the pumps will turn on with the solution going through a return line into the original container. Then, the valve will open to the main vessel allowing a prespecified solution to enter the bioreactor, and when finished, the solenoid valve closes, and the motors turn off. Maintaining the desired biomass temperature involves utilizing a thermocouple, a PID controller, a solid-state relay, and heat tape. The bioreactor vessel is built of a glass cylindrical container with metal lids for positioning and mounting the sensors with a heat tape wound around the outer walls. The heat tape is powered by an external 120 VAC power source, and it is activated when the solid-state relay is sent a signal from the PID temperature controller. The agitator stirrer is run by an electric motor, which is geared down to meet the preferred speed range of stirring for the biomass slurry, and the agitator blades stir the bottom portion of the biomass, keeping all portions from becoming stagnant. The thermocouple threads into the bottom lid of the bioreactor concentric with the agitator shaft and clears the agitator blades because there is a notch in the agitator shaft. The DO and pH sensors are suspended into the top of the biomass, with the probe tips submerged. By optimizing the design parameters of pH, temperature, and agitator speed, the proposed innovative bioreactor will demonstrate the significance and excellence of efficient biogas production, resulting in high-quality biogas energy.

Presenting Author: Austen McKee Tarleton State University

Presenting Author Biography: I am a Mechanical Engineering student at Tarleton State University and I am expected to graduate in May of 2024.

Authors:

Austen McKee Tarleton State University