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In this paper, experimental investigations of an adaptive RST control scheme for the regulation of the ethanol concentration in fed-batch cultures of S. cerevisiae is presented. Our main objective is to prove efficiency and robustness of this controller in experimental applications ranging from laboratory to industrial scales. The controller only requires one on-line measurement signal, making it easily implementable in an industrial environment. Disturbance rejection is ensured thanks to an on-line parameter adaptation procedure, which delivers as a side product an estimate of the growth rate that can be used for process monitoring purposes. The robustification of the controller is achieved in a simple way, using the observer polynomial. © 2009 Elsevier B.V., SCOPUS: ar.j, info:eu-repo/semantics/published

In this paper, experimental investigations of an adaptive RST control scheme for the regulation of the ethanol concentration in fed-batch cultures of S. cerevisiae is presented. Our main objective is to prove efficiency and robustness of this controller in experimental applications ranging from laboratory to industrial scales. The controller only requires one on-line measurement signal, making it easily implementable in an industrial environment. Disturbance rejection is ensured thanks to an on-line parameter adaptation procedure, which delivers as a side product an estimate of the growth rate that can be used for process monitoring purposes. The robustification of the controller is achieved in a simple way, using the observer polynomial. © 2009 Elsevier B.V., SCOPUS: ar.j, info:eu-repo/semantics/published

We have developed a high-throughput miniature bioprocess array for the cultivation of microorganisms in a controlled, reproducible environment. The miniature bioprocess array is based on an array of 150-microliters wells, each one of which incorporates MEMS for the closed-loop control of cell culture parameters such as temperature, pH, and dissolved oxygen. The wells incorporate a suite of sensors, including interdigitated capacitors for cell density, thermopile temperature sensors, and oxygen sensors. Deep reactive-ion etched (DRIE) capacitive sensors enable new capabilities, such as the measurement of cell density in the bulk of the solution. Oxygen is generated by electrolysis, which also provides a means of mixing the solution in the well. Data acquisition, communication, and control will be implemented in foundry CMOS. A four-wire bus connects the electronic interface at each well to each other and to a battery, a clock serial input/output, and ground.

The results of prior lab studies at Tyndall AFB were used to design, fabricate, and demonstrate a pilot-scale, complete AP (ammonium perchlorate) biodegradation (reactor) system using actual effluent from washout of Minutemen stage 2 propellant washout supplied by Aerojet's Propulsion Division. Using an anaerobic reactor (1600 gal) in conjunction with the HAP-1 micro-organism discovered AFRL, it was demonstrated in both tests at both Tyndall AFB and Thiokol-Morton (Utah) that virtually complete destruction of ammonium perchlorate in wastewaters was possible. The operating costs for the bioreactor system shows that fixed costs (electricity, maintenance, and labor) are at a minimum for 2000-4000 ppm perchlorate effluents. This is because maximum thruput can be achieved near 4000 ppm effluents. Nutrient cost is approximately linear with perchlorate reduced. As a result, up to 4000 ppm perchlorate effluents can be treated for less than $0.10 per gallon.