top of page

New Smart Bioreactor is Designed and Built at Portland State University

A new technique to stimulate specific beneficial bacteria for Phosphorus and Nitrogen removal was developed by Bashar Al-Daomi at PSU’s Civil & Environmental Engineering Dept. This technology recently won Bashar the final round prize of $5,000 at PSU’s CleanTech Challenge!

By Bashar Al-Daomi — Portland State U. PhD Student, Institute for Sustainable Solutions Fellow

Wastewater is a crucial environmental issue that we deal with every day. If wastewater is left completely or partially untreated and disposed into our rivers and lakes, it will leave behind high concentrations of organic matters, phosphorus and nitrogen. This will pollute and threaten water ecosystems causing risks to aquatic life species due to algal blooming and high oxygen

At the American Water Works Association’s (AWWA) Water Quality Technology Conference in Portland, OR, November 2017, PSU Ph.D. graduate student Bashar Al- Daomi unveiled a new smart bioreactor he and Dr. Bill Fish have designed and created.

Microbes can do a great job of removing phosphorus and nitrogen pollutants from wastewater if we can design a perfect mutual collaboration between lab researchers, wastewater treatment plant operators and microbes. This collaboration provides us a better understanding of microbial metabolism while we support microbes with optimal life conditions (Dissolved oxygen, nutrients, organic carbon such as acetate, temperature, pH, ORP, etc).

In the Water Quality Lab of Dr. Bill Fish, PSU Ph.D. graduate student Bashar Al-Daomi stepped up to the challenge to develop a smart, simple, reliable, and efficient lab reactor. This reactor aims to show how different types of bacteria (phosphorus accumulative organisms PAOs, glycogen accumulative organisms GAOs, and ammonium oxidation bacteria AOB) grow and interact with each other responding to a variety of control conditions. This reactor focuses on simulating and modelling actual advanced wastewater treatment processes by studying at which low level of both oxygen and organic matter can achieve high phosphorus removal within Enhanced Biological Phosphorus Removal processes?

Bashar, working with technical assistance, created this sophisticated, automated research reactor at a reasonable cost and far less expensive than commercial bioreactors on the market. Bashar took a challenge and made it into an opportunity to develop a cheaper and better product. In fact, the need to be frugal became a central part of the innovation since his goal is to make low-cost wastewater treatment available to areas that cannot afford expensive municipal systems.

This lab reactor is smart since it operates itself automatically based on using timers, sensors, and controllers connected together in one control unit. This unit helps to control and adjust pH and dissolved oxygen measurements to match with different microbial needs. It also collects accurate lab data and builds a trustable database for developing bio-mathematical models.

This reactor can run as a Sequential Batch Reactor SBR that can cover cycles: Anaerobic, Anoxic, Aerobic and sedimentation stages by relying on time not space (controlling the time sequences between each stage). Also, it can be run as one of series of SBRs within continues treatment systems.

This lab system would be beneficial for our students at PSU on conducting capstone and graduate students’ projects besides some applications for environmental engineering course at CEE.

Since the Pacific Northwest-American Water Works Association PNWS-AWWA 2020 vision initiative seeks supporting new young professionals and students who are interested in working on water/wastewater treatment field. This smart bioreactor makes it affordable and easier for colleges and high schools to engage young students and inspire them to become future leaders in water and wastewater purification field. Currently, Bashar and his team are working hard on upgrading the reactor’s design and making it less expensive to fit with a business model that cover 10% of the colleges and high schools’ labs in Oregon and Washington.  Recently, Bashar won the first round of the Portland State University CleanTech Challenge for his reactor and received a $1500 prize. Also, his reactor was selected as one of five finalists. Bashar also won the final round of PSU’s CleanTech Challenge prize and was awarded $5000! PSU has selected him to represent the school to compete with other colleges in Oregon State for the final state $25,000 prize to be awarded this June.

Bioreactor Applications (Applicable Research Ideas)

  • This unit can be used to simulate microbial processes and optimize the metabolisms of organisms that are vital in waste treatment, such as phosphorus accumulative organisms PAOs, glycogen accumulative organisms, GAOs, and ammonium oxidation bacteria AOB.

  • Since this smart reactor uses process technology and automated control, it can be used for optimizing the consumption of dissolved oxygen. This can help with reducing the cost of consumed energy in wastewater treatment.

  • This system can help to develop biological and mathematical models for temperature control, bacterial growth rate, pH control, efficient organic carbon consumption.

  • Another main goal of this system is to combine EBPR technology (Phosphorus removal) with Annamox technology (Nitrogen removal) in one system by maintaining NH3/NH4 not oxidized at low DO as EBPR effluent combining with an anoxic reactor that already has nitrite to create anammox bacteria. This process aims to remove nitrogen with less both organic carbon (acetate or ethanol) and oxygen consumption.

Lab Bioreactor Components

  • A 5-liter jacketed glass reactor (double rings for temperature control),

  • pH sensor, controller (high and low pH)

  • 2 pumps (Acid and Alkaline)

  • Dissolved oxygen sensor and controller

  • Air blower, Oxygen bottle, and Oxygen pump

  • Temperature sensor

  • Oxygen Reduction Potential (ORP) sensor

  • Adjustable float level sensor

  • Adjustable timer/duration agitation,

  • Digital Stirrer Fine air diffuser

  • Sludge drain valve (Ring shape)

  • Organic carbon solution (substrate) injection syringe,

  • Control unit, sensors and Ring diffuser-plastic support (wiring and 3D plastic printing were made by hiring an external technician).


  • No complicated programming is required and high-resolution operational screen is clear and easy to navigate,

  • Reporting flexibility (data can be saved and emailed),

  • Stand-alone and computer sensor interface with a touch screen

  • Collect, analyze, and share sensor data wirelessly with iPad, and Android devices


  • Partial financial support for this work was provided by the MoHESR and PNWS-AWWA scholarships and Beta project and PSU Cleantech Challenge grants.

  • Clean Water Services for providing a mentoring program and UNESCO-IHE for providing innovative online courses on biological wastewater treatment.

bottom of page