A. J. Priestley

Colour and turbidity removal with reusable magnetite particles—VI: Pilot plant operation

Abstract A novel process which utilizes fine magnetite particles for the removal of colour and turbidity from water has been tested in a 60 1 min −1 pilot plant on water from an unconfined aquifer in Perth, Western Australia. The performance of the pilot plant closely matched jar test results. The process design was optimized to achieve a high quality product water on a raw feed which was difficult to treat in the conventional alum coagulation and filtration plant. A comparison of the conventional and magnetite treatment systems is made, which shows that the magnetite process is viable as an alternative water treatment technique.

ION EXCHANGE IN A MOVING BED OF MAGNETIZED RESIN

SUMMARY From the results observed in the treatment of a number of hard alkaline feedwaters it has been shown that the use of a magnetic carboxylic acid resin in a fluidized bed has definite advantages over existing systems for dealkalization. Less resin is needed and simpler plants can handle the same throughput of raw water whilst maintaining product quality. Plant operation is simple and truly continuous without any complex valve system or pressurized vessels. The ability of the resin to treat a turbid effluent of variable composition from a sewage treatment plant has been demonstrated. Cost analyses have suggested that for a large plant, e.g. 1 mgd, changes in reactor design will be necessary to maintain the advantages mentioned above for small scale plants. A number of alternative configurations have been considered, including stirred tank, a high voidage packed bed and an entrained reactor. The final choice depends on the scale of the application.

Rapid Sewage Clarification with Magnetite Particles

As discharge standards for wastewaters have become increasingly stringent, the need for a diverse range of treatment technologies has become more urgent. Physico-chemical processes based on coagulation chemistry have been applied to wastewater treatment, and have been found especially effective for suspended solids removal. This paper describes a novel way to engineer a process based on coagulation/flocculation chemistry. The process is based on the use of very fine magnetite particles, which not only remove the necessity for an extended period of flocculation but also provide very rapid solid-liquid separation by utilisation of their magnetic properties.