Browsing by Author "Goetzman, Harold E"

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Batch Sintering Tests with Bethlehem Steel Mix and Various Fluxes
    (University of Minnesota Duluth, 1989-04-24) Goetzman, Harold E
    A research program to evaluate the performance of Michigan Limestone Operations (MLO) fluxes in the Bethlehem Steel Corporation (BSC) sinter mix was carried out at the Coleraine Research Laboratory (CRL) during the period March 1 to April 10, 1989. This test work was conducted under a contract with MLO to provide the information required by Bethlehem Steel to consider a change in their current flux usage. The sintering tests were to include an evaluation of dolomite strata and size consist in addition to a comparison of BSC and MLO limestone.
  • Thumbnail Image
    Item
    Evaluation of Indian Iron Ore for Direct-Reduction Pellets
    (University of Minnesota Duluth, 1991) Goetzman, Harold E
  • Thumbnail Image
    Item
    Investigation of Papermill Sludge as a Taconite Binder
    (University of Minnesota Duluth, 1989-03-16) Goetzman, Harold E;
    Bentonite has been used by the taconite industry since commercialization of the process in the early 1950's. Although many alternate binders have been tested, including organic materials, bentonite still remains the preferred binder. Bentonite has the unique qualities that promote stable green balling conditions and provides acceptable strengths during drying, preheating, and contributes to the fired pellet strength at an acceptable cost. The incentive to consider other binders is based on such factors as improving the metallurgical properties of the pellets, decreasing their silica content, and lower overall costs. The USBM conducted a number of small scale tests using papermill sludge and other additives in place of bentonite as a binder for taconite pellets. Their balling tests indicated that acceptable green-ball strength could be achieved with papermill sludge. The fired pellet evaluations, however, were based on muffle furnace tests which do not accurately predict the fired pellet quality. Although the fired pellet data were also encouraging it was recognized that pot-grate tests were needed to obtain more definitive test data that could be directly related to commercial practice. Subsequently, the USBM recommended that the IRRRB fund an extension of the program to include pot-grate tests to verify the fired pellet quality obtained in the muffle furnace work. A test program was prepared by the Coleraine Research Laboratory of the Natural Resources Research Institute (NRRI) in cooperation with Dr. J. Nigro and Dr. L. Haas, USBM, and Mr. S. Dickinson, IRRRB. The contract proposal was submitted to the IRRRB January 27, 1988. The contract included evaluation of concentrate and sludge filtering and blending aspects, green-ball quality, and fired pellet quality based on pot-grate tests. This report presents data on all three aspects as stated in the contract and conclusions regarding future efforts in this area.
  • Thumbnail Image
    Item
    Preliminary Testing and Pilot-Scale Processing of the Kittson County Bloating Clays
    (University of Minnesota Duluth, 1996) Oreskovich, Julie A; Goetzman, Harold E
  • Thumbnail Image
    Item
    Second Quicklime Test 03-4 Balling Circuit November 1994
    (University of Minnesota Duluth, 1995-01-16) Goetzman, Harold E; Bleifuss, Rodney L
    There were two main goals to the second test; to determine the long tenn operability of balling circuits using quicklime and to produce green balls equal in quality to those produced using bentonite without allowing the mixed material to sit before balling. Modifications were made to the 03-4 circuit after the May test in order to achieve both of the above and this test was run from November 8 through November 12, 1994. A summary of the results is given below: The test was a success for two reasons. The 03-4 circuit ran smoothly for 4 days using quicklime instead ofbentonite. -.And, because the circuit ran smoothly, a lot of useful and meaningful data was collected and evaluated. The test was completed safely. There were no incidents or accidents reported during the preparation for or during the test. Levels of ammonia and fugitive dust were monitored during the test and found to be lower than during the May test. The levels detected in both tests were well below MSHA requirements. The green ball quality achieved during this test was higher than that achieved during the May test but below desired levels. However, this test, the May test and pilot plant tests all indicate that acceptable quality green balls can be produced using quicklime under the right conditions. Good quality green balls were produced during the May test when the mixed materials were allowed to sit after being mixed, during pilot plant tests when the materials were mixed for 1 minute and during this test when the mixing time exceeded 110 seconds. There were no unloading or handling problems during the test despite the fact that the pulverized quicklime was contaminated with pebble sized chunks. The supplier, Marblehead Lime Company, indicated that the chunks represented contamination from loading bins at their plant. The fired pellet quality on the entire line dropped during both tests despite the fact that quicklime was being used on only one of the four circuits on the line. This appears to be indirectly related to the use of quicklime. It appeared that, during the tests, quicklime reacted with the water in the bentonite and negatively affected the water absorbing properties of the bentonite. The circuits using the contaminated bentonite then produced poorer quality green balls than the circuit using quicklime. The slightly lower quality green balls produced using quicklime combined with the significantly lower quality green balls made with contaminated bentonite and resulted in lower quality fired pellets. This was suspected in the May test and verified during this test.