Lethal Dose of Cyanide

The chemistry of cyanide solutions is complicated because the cyanide ion forms compounds and complexes with many elements. Some cyanide species are highly toxic whereas others are relatively inert and harmless. Molecular hydrogen cyanide (HCN) is the most toxic form of cyanide. Under most conditions, HCN exists as a gas which readily dissipates or reacts with the environment to form less toxic or nontoxic forms of cyanide. Thus HCN is an ephemeral toxin, and many naturally occurring geochemical processes reduce the HCN concentration of a heap system with time.

As discussed below, free cyanide

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By | 2017-03-17T19:06:42+00:00 January 14th, 2017|Categories: Laboratory Procedures, Safety|Comments Off on Lethal Dose of Cyanide

How to Extinguish a Mine Fire

In the anthracite fields of Pennsylvania, mine fires occur with more or less regularity and their existence is an ever-present hazard in coal mining. In all probability 90 per cent, of the mine fires can be ascribed directly or indirectly to the ordinary miner’s open lamp. Other causes may be smoking, electrical installations, gas explosions, gas feeders, and the communication of fire to the outcrops from ash dumps, culm banks, timber and brush fires.

Fires in pump rooms, engine rooms, and barns have been largely eliminated as a result of the Act of Assembly, approved June 15, 1911, which provides

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By | 2017-03-17T19:08:00+00:00 December 23rd, 2016|Categories: Geology, Safety|Comments Off on How to Extinguish a Mine Fire

Underground Mine Ventilation

Efficient ventilation of underground mines consists in having such complete control of air currents that there is always supplied at places where men work sufficient moving air to allow working at maximum capacity without injury to health; and in case of underground fire or of surface fire in the vicinity of mine openings, underground air currents may be quickly reversed if desired, or air may be sent into or excluded from any region and fire fumes confined to only part of the mine workings, instead of penetrating practically the entire mine.

Health and safety of workers in mines as well as proper

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By | 2017-03-17T19:16:02+00:00 October 25th, 2016|Categories: Geology, Safety|Tags: |Comments Off on Underground Mine Ventilation

Cyanide Poisoning Antidote

In 1910, the Committee of the Chemical, Metallurgical and Mining Society of South Africa, appointed to investigate cyanide poisoning, recommend as an antidote to Cyanide Poisoning the following:

  1. Thirty cc of a 23 per cent, solution of ferrous sulphate.
  2. Thirty cc of a 5 per cent, solution of caustic potash.
  3. Two grams of powdered oxide of magnesium (light).

In every cyanide-room there should be kept three boxes, containing—

  1. A metal receptacle to hold about a pint, and a spoon.
  2. A blue hermetically sealed phial, containing 30 cc of a 33 per cent, solution of ferrous sulphate.
  3. A white phial, hermetically sealed, containing 30 cc of caustic potash.
  4. A packet of oxide of magnesium (light).

Preparation of Antidote

Quickly empty the contents of the blue phial, of the white phial, and of the magnesia package into the metal receptacle, and stir well with the spoon. This should be done as rapidly as possible, as the patient’s chance of life depends on promptness.

Administration of the Antidote

If the patient is conscious, make him swallow the mixture at once and lie down for

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By | 2017-03-18T12:26:45+00:00 September 15th, 2016|Categories: Safety|Tags: |Comments Off on Cyanide Poisoning Antidote

Underground Mine Fire Prevention

During the winter and spring of 1917, an unprecedented number of underground fires occurred in the Butte district. With one exception, these fires were caused by the failure of electrical equipment, and called attention to the increased fire hazard in underground mining operations occasioned by the extensive use of electricity.

Five local conditions that contributed toward a heavy fire risk were:

  1. The heavy continuous timbering necessary for mine supports;
  2. the strong ventilating pressures in the shafts and main airways;
  3. the subsidence and faulting movements in the country rock, which ruptured cables and displaced trolley and lighting wires;
  4. the strongly acid mine waters, which quickly developed any weak points in the electrical insulation;
  5. oxidation in old stopes containing large amounts of timber.

In the summer of 1917, a comprehensive plan of fire prevention was begun by the Anaconda Copper Mining Co., which involved a thorough and intensive development of the preventive measures then in use

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By | 2017-03-19T01:34:40+00:00 May 25th, 2016|Categories: Safety|Comments Off on Underground Mine Fire Prevention

Gold Room Security

Very little is documented about Gold Room Security due to the sensitivity of people around it. At the same time, when establishing a new operation it is useful to have a standard security starting point on which to address the issues with directly related to gold room security design fundamentals. This paper will provide guidelines and a ‘prompt’ for the issues to be considered when establishing a new operation. Gold mining invites the inherent problems of vulnerability, threats and countermeasures for the security of gold

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By | 2017-03-17T19:32:40+00:00 March 1st, 2016|Categories: Gold Extraction, Safety|Tags: , |Comments Off on Gold Room Security

Crushing Plant Startup Sequence & Procedure

The following items make up an EXAMPLE Crushing Plant Startup Sequence & Procedure that all must be checked in preparation and before the equipment in the Crushing Plant is started.crushing-plant

If maintenance has occurred since the last operating shift, ensure that the MCC is energized and that all safety locks have been removed from equipment starters. Walk along all conveyors and check belt scrapers, idlers, and pulleys to ensure that

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By | 2017-03-17T19:35:48+00:00 January 26th, 2016|Categories: Concentrator Manuals/Procedures, Crushing & Screening, Safety|Tags: , , |Comments Off on Crushing Plant Startup Sequence & Procedure

Gold Processing Plant Glossary

The point of a cone. The point of a cyclone from which coarse material is discharged. In a cyclone, it is open and the size of the opening affects cyclone performance.

A silver sulphide mineral (Ag2S). The most important silver mineral in the ore.

Barren Solution:
The cyanide/lime process solutions that have had the gold and silver removed.

A filter designed to remove small amounts of fine solids to make a crystal clear solution or water.

Classification: A method of separating different size particles that relies on the relative movement in a fluid

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By | 2017-03-19T06:06:18+00:00 January 25th, 2016|Categories: Concentrator Manuals/Procedures, Safety|Comments Off on Gold Processing Plant Glossary

Fire Prevention in Mineral Processing Concentrator Plant

A fire prevention and control program must have the understanding and the cooperation of every employee in order to be effective. Although the overall program is under the direction of the mine manager, each employee on the job does have a direct responsibility for the program.

The mine manager, because of his knowledge of the operation, is in an excellent position to determine the fire prevention measures necessary. He should be able to recognize the need for specific fire protection equipment and should take necessary steps to see that such equipment is provided.


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By | 2017-03-17T19:35:56+00:00 January 25th, 2016|Categories: Concentrator Manuals/Procedures, Safety|Comments Off on Fire Prevention in Mineral Processing Concentrator Plant

Hydrochloric Acid & Sodium Cyanide

Even a small concentration of hydrochloric acid in the air irritates the membranes of the respiratory tract making it easily detectable in amounts below the Threshold Limit Value of five parts per million. One to five parts per million can be detected by smell, while five to ten parts become disagreeable.

In addition hydrochloric acid mixed with sodium cyanide liberates HCN gas. This is extremely dangerous (read the cyanide safety section). Contact of hydrochloric acid with any cyanide containing solutions must be avoided.

Personal protective equipment is not an adequate substitute for

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By | 2017-03-17T19:35:58+00:00 January 25th, 2016|Categories: Concentrator Manuals/Procedures, Reagents and Chemicals, Safety|Tags: |Comments Off on Hydrochloric Acid & Sodium Cyanide