Operation and Use of a Mercury Vaporizer

Open the cover of the mercury still and mix talcum powder (or substitute with chalk powder, graphite powder, iron oxide powder, etc.) with water to form a paste. Apply it evenly to the inner wall and bottom to prevent the distillation residue from sticking to the inner surface.

2. Place the pure hard mercury paste, washed by pressure filtration, into the mercury vaporizer, maintaining a paste layer thickness of 40 to 50mm; excessive thickness may lead to incomplete mercury distillation. Prevent mercury paste from boiling and gold particles from splashing into the outlet pipe.

3. Secure the lid of the mercury vaporizer, tighten the fixing bolts, place the vaporizer on the combustion furnace, connect the water pipes, and insert the outlet of the exhaust pipe into a basin of water. Prepare for mercury distillation.

4. Ignite the furnace, adjust to a low flame for slow heating, and remember not to heat up rapidly. (The decomposition temperature of the mercury-gold solid solution in hard mercury paste is close to the boiling point of mercury. Rapid heating can cause the mercury-gold solid solution in the hard mercury paste to not decompose and instead directly enter into sublimation and vaporization of mercury, leading to violent boiling and splashing.)

After approximately 30 to 50 minutes, adjust the combustion furnace to medium heat. The mercury inside the steam distillation unit vaporizes into mercury vapor due to the high temperature and escapes from the tank into the exhaust pipe. As the mercury vapor passes through the water jacket of the exhaust pipe, it condenses into liquid mercury due to the circulating cooling water, which then drips into the cold water basin for collection.

6. For the later stage of the mercury distiller (where there is no obvious mercury liquid discharge through the exhaust pipe), adjust the furnace to high heat and continue to distill mercury for 30 minutes to ensure complete distillation of the remaining mercury in the mercury paste.

7. Elevate the outlet of the mercury vaporizer's exhaust pipe above the water level in the basin, shut down the combustion furnace, open the mercury vaporizer's pressure relief valve to maintain a pressure balance inside and outside the unit, and prevent any hazards. (The balanced pressure inside the mercury vaporizer will become negative as the temperature drops; the exhaust pipe inserted into the cold water basin can draw cold water back into the vaporizer, posing an explosion risk.)

8. Remove and collect the mercury liquid from the water basin, and then reuse it in the mercury mill and mercury board. (If the mercury liquid becomes dirty or its color darkens, losing its metallic luster, it can be cleaned by washing with a 5% to 10% dilute nitric acid or dilute hydrochloric acid solution.)

9. After the mercury still has completely cooled, open the lid of the mercury still and remove the sponge gold.