Biomedical subjects

P A Lant

Publications and source records attributed to P A Lant.

5 recordsLinked to original sources

PubMed2001

Biodegradation of high strength phenolic wastewater using SBR.

This investigation demonstrates the capability of a bench-scale sequencing batch reactor (SBR) to biodegrade an inhibitory substrate at a high loading rate. A SBR loading rate of 3.12 kg phenol.m3 d-1 (2.1 g COD.g-1 MLVSS d-1) with a COD removal efficiency of 97% at a SRT of 4 days and a HRT of 10 hours was achieved; this rate was not reached before. The SBR was operated at 4 hours cycle, including 3 hours react phase. The synthetic wastewater of 1300 mg/L phenol was the sole carbon source. Oxygen uptake rates (OUR) were monitored in-situ at various stages of the SBR. The oxygen mass transfer coefficient, KLa, of 12.6 h-1 was derived from respirometry. Use of respirometry in SBR aided the tracking of the soluble substrate through OUR.

Aerobiosis↗

PubMed2001

Using the flexibility index to compare batch and continuous activated sludge processes.

This paper considers the question of which is better: the batch or the continuous activated sludge processes? It is an important question because dissension still exists in the wastewater industry as to the relative merits of each of the processes. A review of perceived differences in the processes from the point of view of two related disciplines, process engineering and biotechnology, is presented together with the results of previous comparative studies. These reviews highlight possible areas where more understanding is required. This is provided in the paper by application of the flexibility index to two case studies. The flexibility index is a useful process design tool that measures the ability of the process to cope with long term changes in operation.

Bioreactors↗

PubMed2001

Activated sludge flocculation: direct determination of the effect of calcium ions.

The effect of calcium on activated sludge flocculation dynamics is investigated using a unique experimental technique. The technique allows on-line analysis of the size of activated sludge flocs during flocculation and provides valuable insight into the mechanisms of flocculation. Activated sludge samples were firstly sonicated for 3 minutes at 50 W and then stirred at 100 rpm. The floc size was subsequently measured on-line using a Malvern Mastersizer/E. For concentrations of calcium less than 4 meq/L no significant increase in final floc size was observed even though an increase in the initial rate of change of floc size could be seen. Addition of calcium greater than 4 meq/L resulted in a dramatic increase in floc size. Results from this investigation support the theory that cations are involved in flocculation through cationic bridging, and will be used in ongoing investigations to model the flocculation process.

Calcium Chloride↗

PubMed2001

Using the World Wide Web to revolutionise technology transfer and training in the water and wastewater industries.

Industry professionals of the near future will be supported by an IT infrastructure that enables them to complete a task by drawing on resources and people with expertise anywhere in the world, and access to knowledge through specific training programs that address the task requirements. The increasing uptake of new technologies enables information to reach a diverse population and to provide flexible learning environments 24 hours a day, 7 days a week. This paper examines one of the key areas where the World Wide Web will impact on the water and wastewater industries, namely technology transfer and training. The authors will present their experiences of developing online training courses for wastewater industry professionals over the last two years. The perspective is that of two people working at the "coalface".

Diffusion of Innovation↗

PubMed2001

Operating space diagrams: a tool for designers of wastewater treatment plants.

Recent years have seen the introduction of new and varied designs of activated sludge plants. With increasing needs for higher efficiencies and lower costs, the possibility of a plant that operates more effectively has created the need for tools that can be used to evaluate and compare designs at the design stage. One such tool is the operating space diagram. It is the aim of this paper to present this tool and demonstrate its application and relevance to design using a simple case study. In the case study, use of the operating space diagram suggested changes in design that would improve the flexibility of the process. It also was useful for designing suitable control strategies.

Computer Simulation↗