Patents by Inventor Andrew J. Dalzell

Andrew J. Dalzell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5108626
    Abstract: A process for the recovery of coal particles having a maximum dimension of less than 2 mm from coal tailings including the steps of forming a slurry (101) of tailings having a pulp density of from 10 to 30% by weight; feeding the slurry into a hydrocyclone (103) to produce an underflow second stream which contains the tailing particles over a predetermined size and some of the gangue particles smaller than that size and an overflow stream containing the coal particles smaller than the predetermined size and the balance of the gangue particles, the hydrocyclone (103) being operated such that the underflow stream has a pulp density of from 40% to 60% by weight; adjusting the pulp density of the second stream, if required, to from 20 to 50% by weight; passing the repulped second stream over a rapped or vibrated sieve screen deck (105) having a wedge wire sieve screen with a radius of less than 2 m, an arc angle of from 45.degree. to 60.degree.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: April 28, 1992
    Assignee: Minpro Pty. Limited
    Inventors: Jeremy J. Lees, Andrew J. Dalzell, Murray H. Pryor