Test results of bacterial leaching with an enlarged continuous device (1)

Moscow Institute of steel and alloys and research work of the Central Research Institute of Geological Survey scientifically proven bacterial leaching method is suitable for processing refractory arsenic concentrate. This concentrate is characterized by the inclusion of very fine-grained precious reconstituted parts in arsenopyrite. Compared with the calcination method, the bacterial leaching method does not have a phenomenon in which the surrounding environment is contaminated by harmful arsenic compounds when recovering precious metals.

Despite the many advantages of bacterial leaching, but since this a long time - a method yet to emerge scope of laboratory research. It was only in 1974 by the Central Institute of Geological Exploration, the Moscow Institute of Steel and Alloys and the All-Su Gold, Platinum, Diamond and Tungsten- Molybdenum Industrial Scientific Research and Design Institute at the Central Geological Exploration Science Research Institute < in Tula City ) developed into the first Soviet - after the expansion of the test table means for closed circulation of the continuous culture under conditions of microorganisms such as bacteria leaching could be realized.

This paper include first time bacterial leaching process to expand the results of the test. Containing As8.4% ; S24.1% ; Fe26.6% gold - arsenic flotation concentrate requires bacterial leaching. The metal minerals in the concentrate have sulfides (about 60% ), of which the ratio of pyrite to arsenopyrite is 2 : 1.5~1 . Most of the gold is symbiotic with arsenic pyrite, while a small part is symbiotic with pyrite.

The microorganisms in the enlarged Patricia device are used to decompose the sulfides of arsenic and iron in order to dissociate the fine particles impregnated with gold in the sulfide. The equipment connection diagram of the expansion device is shown in Figure 1 .

The processing capacity of the expansion device is 50~60 kg / day and night. Ten Pachuk troughs are arranged in series in two rows. The effective volume of each slot is 150 liters . Pa Qiuke a slot left alone for the preparation of a solution containing bacteria.

The slurry is self-flowing by means of an overflow pipe connecting the Pachuk troughs. The slurry from the blower PMK-2 agitates the slurry at a pressure of 1.0-1.2 atmospheres. The temperature of the Pachuk trough is maintained at 28~ 32 °C In between, the method relies on the circulation of hot water around the "heating jacket" around the Pachuk trough.

The test was conducted in three main phases.

I. Prepare and obtain lively bacterial substances.

II. The starting device is placed in a normal operating state and leached under specified conditions.

III. Cyanide the bacterial leach residue.

In order to obtain active substances of bacteria, we have used the same laboratory with - microbial culture bacteria "Thiobacillus coli" bacteria solution. The microbial culture was diluted 4 times with Cna~nepuan and several yg~rpeE culture mediums , and there must be a concentrate of research. The ratio of solution to medium is 1 : 2 . Concentrated hydrogen ion with H2S04 , pH : 2.2~2.5 .

The method of preparing the solution is described as follows; in the flask or the Pachuk tank of the laboratory, after blowing air into the bacterial liquid containing the medium and the concentrate, at 30~ 32 °C Get 10~ at temperature 15 liters Bacterial solution. The degree of solution preparation was determined based on the degree and rate of oxidation of the ferrous iron in the medium.

The resulting solution was re-diluted with medium. This is repeated for a job until the number of bacteria disappears.

Then the solution ( 30~ 45 liters Provided to the enlarged Patricia device and prepared for the active bacterial quality necessary to start the test under continuous culture of microorganisms ( 600~) 800 liters ).

Pa Qiuke along the normal state in that slots (a slot from the last slot to the front) gradually increasing the concentration of the pulp, so that a very dilute slurry (solid: liquid = 1: 100) to achieve a given concentration (solid: liquid =1 : 4~5 ).

The thick continuous slurry concentrated bacteria from the contact tank (solid: liquid = 1: 5) to the - of a solution containing bacteria Pa Qiuke groove, thereby gradually Pa Qiuke grooves filled with all bacterial solution and make The pulp becomes thicker.

In this case, the best conditions for the culture activity and the leaching of the concentrate can be guaranteed. Leaching under optimal conditions is achieved after the density of the bacterial culture in all Pachuque tanks reaches 16-20% . The content of arsenic sulfide in the solid at the discharge port of the device is stabilized, which is one of the signs of achieving the prescribed process. When working under defined conditions, measure all of the process's metrics and gather the leaching products needed for the next study.

Flange safety Shields

Commonly used location

piping nerar head and eye level

piping near walkways and traffic areas,including areas with overhead piping.

Unloading/loading areas,including docks and terminals.

Piiping on discharge side of pumps.

Piping in tight,confined spaces.

piping conveying flammables near hot surfaces and instruments panels

Fittings,flange shield,silicone rubber fabric tape

Taixing Yingxing Composite Material Co.,Ltd , https://www.ptfecnyx.com