Date of Award
Master of Engineering (Research)
Cork Institute of Technology.
Noel B. Duffy
This thesis was originally conceived as a potential Masters Degree research programme by the management of ADM Ringaskiddy as a means of maximizing throughput through the plant’s wastewater treatment facility. This facility is a major producer of citric acid using beet molasses and a fermentation process. It was proposed that removal of a compound, known as betaine, from the citric acid process waste stream would reduce the Chemical Oxygen Demand (COD) content of the waste requiring treatment before disposal. This would be achieved by using the citric acid process waste as the feedstock for a betaine extraction process. The wastewater treatment facility in ADM Ringaskiddy is one of the major “bottlenecks” in the process stream and prevents any increase in production levels. Removing a considerable part of the COD content would also have environmental benefits and assist meeting current and future environmental regulations.
Such aspirations also made sense from a financial point of view, as betaine is worth a considerable sum of money in purified form. Every year, literally millions of Euro worth of betaine were “going down the drain”. The ambition of this thesis was that the marketable value of produced betaine would offset the considerable capital expense of the equipment required.
In summary, separation of betaine from the waste stream is technically feasible but considerably more work is required to achieve a working model or a pilot rig, where extraction of betaine could be studied on a continuous or semi-continuous mode rather than using batches of feedstock. The difficulties encountered during the study stemmed from the fact that the process waste is full of molasses residue and liable to biodegradation. During use of the CSEP (Chromatography SEParator) pilot rig, it was noticed that the resin within the column had a finite life span. It is possible to acquire high purity betaine solution at a high recovery rate from the CSEP pilot rig but this is often at the expense of resin life span.
From the investigations during this thesis, it is recommended that a two-stage separation process be utilized. The first stage separation would remove the bulk of the molasses impurities with a high recovery of betaine and the second stage separation would refine the solution to give a high purity betaine product at some expense of recovery.
Burkley, Colin G., "Extraction of a Valuable Compound from a Waste Stream for ADM Ringaskiddy" (2003). Theses [online].
Available at: https://sword.cit.ie/allthe/337