L David Michaud

About David Michaud

Since 1993, when he obtained his Mining Engineering Degree from Queen’s University, David has acquired experience in operating roles including many years in post-commissioning operations troubleshooting. Mineral Processing and Metallurgy has become a core strength and passion for Mr. Michaud.Learn more at https://www.911metallurgist.com/about-us/

Spent Alumina Regeneration

Regeneration of the spent alumina was accomplished by using 0.25% NaOH and 0.5% NaOH. Figure 11 shows the release of selenium, silica, and aluminum when regenerating the adsorption columns that had received the mine leachate. In this case, the regeneration was performed in an upflow mode using 30% bed expansion. As expected, the losses of aluminum

←   Read The Full Metallurgy Article
By |2018-07-12T16:04:24+00:00July 12th, 2018|Categories: Various|Comments Off on Spent Alumina Regeneration

Kaolin Ceramics

clay-minerals magnetic separator

Kaolin is a clay comprised essentially of the mineral kaolinite which has the oxide composition of 46.3% SiO2, 39.8% Al2O3, and 13.9% combined H2O. The structural formula of kaolinite is (OH)8Si4Al4O10. These deposits are sedimentary and contain approximately 90% or more kaolinite along with minor quantities of quartz, mica, and smectite along

←   Read The Full Metallurgy Article
By |2018-05-01T14:36:33+00:00May 1st, 2018|Categories: Various|Comments Off on Kaolin Ceramics

How to Derate a Pump Curve for Slurry Pumping

The pump curves published by pump manufacturers are for the performance of the pump on water. Some pump manufacturers use a derating factor to correct the head and efficiency of the pump when pumping slurry.

This a subject which has had a lot of controversy and disagreement It is suggested that the method used be left to the manufacturer The method

←   Read The Full Metallurgy Article
By |2018-05-01T12:24:53+00:00May 1st, 2018|Categories: Pumps and Pumping|Comments Off on How to Derate a Pump Curve for Slurry Pumping

Silver Chloride Chemistry

To appreciate the development of industrial silver chloride processing it is helpful to outline some of its general properties. Since more comprehensive reviews are available, only basic concepts will be covered here.

Silver chloride is a white, curdy, crystalline solid compound. In the lab, it is prepared from a solution of AgNO3 by precipitation

←   Read The Full Metallurgy Article
By |2018-04-29T15:07:24+00:00April 29th, 2018|Categories: Various|Comments Off on Silver Chloride Chemistry

Effect of Air Flowrate on Flotation Column

On a flotation column cell, the variation of concentrate flowrate, clean coal yield and product grade with air flow rate are shown in Figure 4. These tests were carried out using a 5 wt. % feed slurry. The results show that the concentrate flow rate, yield and product ash content increased with air flow rate. This trend is expected since the available

←   Read The Full Metallurgy Article
By |2018-04-29T12:08:15+00:00April 29th, 2018|Categories: Various|Comments Off on Effect of Air Flowrate on Flotation Column

Visman’ General Sampling Theory

A comprehensive analysis of the entire range of related studies would require a lengthy discussion. Instead, this paper will focus only on the work of Visman (1962, 1969), because his work is part of the current ASTM D2234 standard on coal sampling (American Society for Testing and Materials,

←   Read The Full Metallurgy Article
By |2018-05-22T01:34:22+00:00April 28th, 2018|Categories: Various|Comments Off on Visman’ General Sampling Theory

How to Reduce Ball Mill Overload Risk

Two different circumstances must be addressed for the reduction or elimination of overload risk: a) in existing operations, or b) in the design of new grinding circuits. The methods necessary are in the first case an adjustment of operating conditions; and in the second an adjustment of mill shapes.

Existing Operations: from Equation

←   Read The Full Metallurgy Article
By |2018-04-24T12:47:48+00:00April 24th, 2018|Categories: Grinding|Comments Off on How to Reduce Ball Mill Overload Risk

Column Flotation BIAS

Counter Current flow of mineralized bubbles & wash water

The column underflow is always of slightly higher volume than the feed. This volume imbalance, called BIAS in the control system, is made up by wash water inserted at the top of the column. Part of this wash water travels down the column to exit with the underflow. The remainder overflows with the loaded bubbles.

It is this unique application of wash

←   Read The Full Metallurgy Article
By |2018-04-24T15:34:19+00:00April 23rd, 2018|Categories: Various|Comments Off on Column Flotation BIAS

Gold Refining Contract

The operator’s relationship with the refinery depends entirely upon a well-defined written contract, good representation at the refinery and the use of reliable assay laboratories. While all contracts are similar in that they are meant to safeguard the interest of both refiner and miner, it is not unusual to find a single refinery writing a

←   Read The Full Metallurgy Article
By |2018-04-23T17:45:59+00:00April 23rd, 2018|Categories: Various|Comments Off on Gold Refining Contract

Gallium Uses

Gallium: Cominco has been at the interface between the semiconductor materials and the components industries since the commercialization of the transistor in the early fifties. Based on our commitment to R&D, we have become the largest merchant supplier of several specialty semiconductor substrates

←   Read The Full Metallurgy Article
By |2018-04-23T16:51:23+00:00April 23rd, 2018|Categories: Various|Comments Off on Gallium Uses
I Need Consulting Engineering Help
I Need Ore Laboratory Testing