EVALUATION OF THE HABER COLD PROCESS
for
Haber, Inc.
Towaco, New Jersey
by
T. F. Izzo
7
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Pincock, Allen & Rolt, Inc.
1750 East Benson Highway
Tucson, Arizona 95714
August 1985
PAR Project No. 611.00
August 21, 1995
Mr. Robert w. McPherson
Executive Vice President
Haber, Inc.
470 Main Road
Towaco, NJ 07092
Dear Mr. McPherson;
Enclosed are three copies of the Pincock, Allen & Molt, Inc. report on the Evaluation of the Haber Gold Process
We genuinely appreciate the opportunity to have worked with you and your people on this most interesting project, and look forward to a continuing good relationship with Haber.
If you have any questions or comments regarding the report, please contact me.
Yours very truly,
PINCOCK, ALLEN & HOLT, INC
Senior Process Engineer
EVALTIATION OF THE RARER COLD PROCESS
o The Haber Cold Process is a novel method for processing gold ores that offers various advantages aver present techniques.
o The Haber Cold Process extracted gold in bulk and in significantly less time than is possible with cyanide. Recovery rates were exceptionally good, particularly when compared to cyanide on the ores tested.
o The Saber Cold Process responded to the conventional procedure of recovering the gold from solution using activated carbon.
o The Saber Gold Process does not require any exotic equipment or hardware, nor pose unusual engineering problems in the design or fabrication of a commercial plant.
o Handling requirements for the chemicals used are significantly less stringent than those practiced for cyanide. This should simplify waste disposal.
o In the tests observed, the Haber Cold Process extracted 99 percent of the gold from a low grade ore from the Cripple Creek district of Colorado and 93 percent of the gold in a high grade ore concentrate from the Victorville area of California. In both instances leach time was completed in 6 hours. In both tests,flaber processed the ores as received and did not attempt to optimize extraction by size reduction.
o Haber. Inc. has demonstrated effective processing and assay procedures.
o Further design data is suggested before the Process is commercialized far any particular ore.
While clearly different in chemical substance, the HGP is very similar in form to cyanide vat leaching where ground ore is interacted with lixiviant that chemically solubilizes the gold The gold reagent solution can then be treated with activated carbon where the gold is absorbed and subsequently stripped using conventional techniques.
The actual composition of the lixiviant is proprietary, however, it consists of a consumable reactant labeled AP3, a catalyst or potentiator, designated as ?C, and a mineral acid used to condition the ore that is a function of a particular ore's minerology. In some instances, Haber reports the addition of the mineral acid is not necessary. They also note that when the mineral acid is indicated, it is often more economic to float the Ere free of acid consuming minerals such a calcite than bear the expense of neutralization.
The Haber system should be tailored for each type of ore it is to process. In the tests that the writer observed, the ratio of lixiviant to ore processed (solids) was varied from 1:1, where the weight of 240 gallons of liquid is approximately one ton, to 2:1. Haber explained that an objective in developing Haber also contends that the lixiviant can he recycled in a commercial plant which would require a make-up of reagents to equal those lost in the liquid-solids separation, about 95 gallons out of the 240 gallons used, and an amount of AP3 corresponding to that consumed in reacting with the gold.
This fact remains to be confirmed and should be the subject of pilot tests on an ore Haber plans to commercia1ize.
In demonstrating the naber Gold Process, naber relied on decantation and washing in order to remove the gold pregnant solution from the tailings. This technique is widely practiced in the mining community usin9 thickeners. During the demonstration witnessed by the writer, saber did not attempt to maximize this procedure other than to its feasibility. The separation was sufficient to determine this procedure is adequate and that a conirnercial installation would most likely be more effective in reducinq the amount of wash water that would be required to recover the solubilized gold a flow circuit for a specific ore is to minimize this ratio, and that they believe a iti ratio is possible as demonstrated with the Cripple Creek ore. When dealing with small quantities such as with the Black Hawk ore, the first priority was to verity that high recovery rates were possible, and that the 2:1 ratio was used to be certain that after the liquid-solid separation there would be sufficient solution to effect a carbon absorption.
During the period from July 1 to 4, 1983, the writer observed the pilot testing of the Haber Gold Process and the Alpha Process at the Silver Tech Mine pilot plant located two miles southwest of Tombstone, Arizona. This report deals with the testing of the Haber Gold Process for the recovery of gold from precious metal ores. A copy of the Haber9 Inc. report on the conduct of the Haber Cold tests is enclosed with this report.
In conjunction with the Saber Gold Process evaluation, the writer collected 29 samples of various input chemicals, process streams and products from the pilot tests. These samples were prepared and assayed independently by Skyline Labs, Inc. in their Tucson, Arizona laboratory. The PAH sample descriptions and results are presented in Tables I and II. The assay results show good agreement with the Haber samples taken at the same points in the process at the same time, and that the preparation and assay procedures used by Haber are in accordance with good practice.
In the testing of the Haber Process on ore from Cripple Creek Colorado, 225 gallons of water, i.e kilograms of a reagent identified as FC 20 gallons of AP3, and 5 gallons of UA were reacted with 2000 pounds of ore in a rotating tumbler for sir hours. The details of the test are presented in the enclosed report by Haber, Inc.
The leach solution contained 89.4 percent of the gold in the original 0.032 ounce Au per ton ore.
The residue was washed and decanted twice to remove the soluble gold values from the solids. As shown in the enclosed Haber report, 225 gallons of the combined supernatants were treated with 1 pound of activated charcoal to absorb the contained gold. After several hours, the calculated loading on the carbon was 9.4 ounces of gold per ton of carbon, the measured loading on 0.81 pound coarse carbon collected after the loading step was 6.3 ounces per ton. The tine carbon collected contained 19.64 ounces of gold per ton.
A portion of the coarse carbon was stripped using an aqueous solution containing 2 percent caustic soda and 0.1 percent sodium cyanide by weight. The solution also contained 20 percent ethanol by volume. The stripped carbon contained 0.075 ounce of gold per ton, indicating that the gold in the Haber leach liquor can be loaded and stripped using activated charcoal.
The recovery of gold in leach liquor to be treated by further processing can be represented as 0.032 oz Au/ton x 0.894 x 0.96 or 0.028 ounce Au/per ton, using the pilot plant leach recovery of 89.4 percent, and assuming a soluble loss of 2 percent on an ore continuing 0.032 ounce of gold per ton. Preliminary indications are that the gold in solution is recoverable by carbon absorption and stripping techniques.
A summary of the leach reagentEcosts from the Haber report are as follows.
Cripple Creek Ore - Leach Reagents
Reagent Cost Usage/Ton ore $/Ton Ore
FC 0.25/Kg 1.8 Kg 0.45
HA 0.30/gal 5.0 gal 1.50
AP3 0.40/gal 20.0 gal 9.00
Leach Reagent Total $9.95
Preliminary order of magnitude direct costs for treating 2000 tons per day of Cripple Creek ore using the Haber Process ore are as follows:
Crushing Steel X 3/Ton Ore
Leach Reagents 0.37
Carbon 9.95
Strip Chemicals 0.30
Flux Chernicals 0.02
Other Direct Operating Costs 5.94
Total $16.66
On July 3, a test of the Haber Process was made on 250 pounds of Black Hawk Mine ore containing 0.93 ounce of gold per ton. The details of the test are reported in the enclosed Haber Inc. report. In that test, 92.6 perdent of the gold was extracted in the leach; 99.6 percent of the gold in solution from an earlier test on the same ore was absorbed on activated charcoal.
A Summary of the reagent costs for treating Black Hawk ore is as follows:
Black Hawk Ore - Leach Reaqents
Reagent Usage/Ton Ore $/TON Ore
FC 0.25/Kg 6.04 Kg/ton 1.51
HA 0.30/gal 40 gal/ton 12.00
AP3 0.40/gal 40 gal/ton
Leach Reagent Total $29.51
Preliminary order of magnitude direct costs for treating 500 tons per day of Black Hawk ore are as follows:
Crushing Steel 0.37
Leach Reagents 29.51
Carbon 0.10
Strip Chemicals 6.90
Flux Chemicals 0.60
Other Direct Operating Casts 9.63
Total $47.11
CONCLUSION:
The economics of the Haber Gold Process appear to be sensitive to the concentration of reagents, the amount of calcite in an ore, the liquid to solids ratio and the extent recycle is possible in any given processing scheme.
Establishing the economics and viability of a complete process utilizing absorption of the gold in the leach liquor on activated charcoal, stripping of the charcoal and production of a dare gold product should be pursued with vigor in order to effectively develop a complete Haber Process for the recovery of gold from precious metal ores. This work should be focused on a gold ore Haber is planning to commercialize.
TABLE I
HABER COLD PROCESS SAMPLES, NEWPORT MINERALS ORE(Cripple Creek)
Taken bv Pincock. Allen p Holt. Inc.
E 1965. Tombstone, Arizona
Sample Sample Results
Description No. SamDle Preparation Oz Au/Ton
Read Sample 1 Pulverize 0.030
Liquid Reagent 2 Mane <0.005
Water for Leach 3 None <0.005
Acid and Solid Reagent 4 None <0.005
and Water
4:10 pm Leach Liquor 5 None 0.075
5:10 pm Leach Liquor 6 None 0.040
6.'10 pm Leach Liquor 7 None 0.040
7:10 pm Leach Liquor 8 None 0.025
8:10 pm Leach Liquor 9 None 0.045
9:10 pm Leach Liquor 10 None 0.040
1st Leachate 11 Clarify and Run solution 0.050
1st Wash 12 clarify and Run Solution 0.015
Pregnant shines 13 Filter and wash solids, Assay 0.010
Washed and Dried Solids Only
sands from Pregnant 14 Dry and Pulverize 0.005
2nd wash 15 Clarify and Run Solution 0.005
Carbon Adsorption reed 16 Clarify and Run Solution 0.020
Carbon Adsorption, 4 HR 17 Clarify and Run Solution 0.015
Carbon Solution Tail, 7 Hr 18 Clarify and Run Solution 0.015
Carbon Adsorption 19 None 0.010
Final Solution
Sand Residue 20 Dry and Pulverize <0-005
Loaded Carbon 21 None 6.78
3 Hr C Strip Solution 22 None 0.23
10 Hr C Strip Solution 23 None 0.025
14 Hr C Strip Solution 24 None 0.010
Stripped Carbon 25 Filter, Dry and Assay Solids 0.075
TABLE II
HABER GOLD PROCESS SAMPLES, BLACKHAWK MINE ORE
Taken by Pincock, Allen & Holt.
July 3 and 41 1995, Tombstone, Arizona
Sample Sample
Results
Descriptipn No. Sample Penetration Oz/Ton
Head 5ample 70 Dry and Pulverize Au 1.02 Ag <.005
5 Hr Lead Liquor 72 Filter and Run solution Au 0.385 Ag 0.03
6 flr Lead Liquor 74 Filter and Run Solution Au 0.395 Ag 0.03
2, Black Hawk Mines 75 Au 0.155
Final Tail Ag <.005
There is about 8 more pages but it is not OCR-able. Sorry did the best I could on scanning and translating the document.
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