The complex designed by specialists
of our company allows the efficient
beneficiation of own deposit of gold
K.L. Pentzel, Chief Technical Officer
«Gold Mine Technology» JSC
Within the several recent years along with positive dynamics of gold price growth the gold miners of our country became more active as well — both existing and potential enterprises. New names are coming into the gold mining, and they are interested in entering and settling in this business. All this can stimulate, in particular, both the development of branch and the development of economy in general. However the main problem for small gold mining business is availability of resource base. It is not a secret for anybody that the greatest part of stocks and resources belongs to radical deposits. At the same time geological exploration works, construction and commissioning of the ore deposit, if we speak about the new enterprise, demand enormous capital investments. For the significant part of representatives of small and medium business this becomes very difficult. Another thing is to begin or continue the development of the loose gold deposit.
Having obtained the license for the right of subsoil use, after the registration of the whole required package of authorization documentation, the subsoil user can immediately begin production from small volumes, by means of commissioning of one or several washing units. Here it is worth making a reservation that before 2017 the development was possible only at deposits with the confirmed stocks. Today for the development of pillar alluvial deposits the procedure remained as before, however in terms of the development of technogenic deposits the life of gold miners became easier after the letter from the Federal Agency for Subsoil Management «Concerning some features of the development of technogenic (earlier broken by production) alluvial gold deposits» No. CA-04-30/10154 dated 01.08.2017 (its prolonged edition). Thanks to this letter the subsoil user can skip long and expensive stage of exploration works for the development of technogenic gold deposits. All stocks are defined by the pilot development planning allowing the acceleration of the startup of gold mining site considerably.
Today there are less perspective pillar alluvial gold deposits year by year. Besides this, their opening is impossible without conducting of full geological exploration works. However there are a lot of technogenic deposits appeared within many years of operation. Their resource over the country can be estimated as hundreds of millions of cubic meters.
Industrial development of technogenic deposits can stimulate several factors at the expense of which the repeated development becomes profitable. Such factors are, first, high current and perspective price of gold; second, the imperfection of the applied technologies and devices during recent years, operational and technological losses due to which were considerable; third, preparation of authorization documentation excludes the stage of geological exploration works in their classical way (which was mentioned above) and allows to calculate stocks by means of pilot development planning that considerably reduces terms of commissioning of the technogenic field.
Considering all aforesaid, the «Gold Mine Technology» JSC, besides sales of the equipment for development of alluvial fields became the full-scope independent subsoil user, having obtained the license for the field of alluvial gold in the Amur region.
Our company achieves the result at the expense of application of own design — the washing and screening complex (WSC) on the basis of inertial screen with application of jigging technology.
The deposit purchased by «Gold Mine Technology» JSC is notable for the existence of the large amount of fine gold which was lost by local mining partnerships because of imperfection of disintegration and extraction by primary mining in the early nineties. All metal of the technogenic deposit is concentrated in lixiviation dumps from recent years. Besides this, domestically manufactured bulldozers T-130 popular at that time could not make qualitative «stripping» and opening of radical rocks in the manner as it is done by modern heavy bulldozers and excavators. Existence of pillar deposits left by subsoil users of recent years in opencast boards can become one more positive factor for the development of the technogenic gold deposit.
All the above mentioned facts anyway are present at the deposit of «Gold Mine Technology» JSC. After the procedures of registration of all necessary permissions and coordinations in August, 2019 our company started the gold mining process.
The publication of all qualitative and quantitative parameters of production requires a certain statistics and the time period of trouble-free operation. However it is possible to declare with confidence that the chosen technique and the equipment have high efficiency. There are first kilograms of the gold-bearing concentrate consisting fine, sometimes hardly seen to a human eye metal, received.
Briefly about the technology and WSC
The equipment in the developed complete set is suitable both for technogenic and for pillar alluvial deposits.
Principle of operation
Supply of sands into the washing and screening complex (WSC) can be carried out by two ways:
- Bunker way with application of «transporting» water.
- The complete set including the reception bunker and a vibration feeder, task of which id the forced uniform supply of highly clay sands to the screen for washout and classification.
The WSC is completed by one of inertial screens of heavy type (depending on desirable productivity): GIT-42M, GIT-52MB, GIT-62MB, GIT-62ME or GIT-72! Screens are equipped by the system of washout which was designed taking into account the possibility of pressure regulation in nozzles along the whole area of the washing flight.
The screen can be completed by one or two sowing flights.
The concentrating system of the WSC has gate structure. Depending on the nature of scattering two options are possible:
- Two gates 12 m long each.
- Four gates 6 m long each.
The specific feature of the system of gates is the existence of cavitator at the interface between the effluent pipeline and gates. The target of this cavitator is slowing down of the effluent stream by counter jets of water which arrives from the uniform supply system of the complex. Thus, by means of adjusting of angles of jets we can slowdown the effluent stream for the better washout of rock and the maximum extraction of hard-cleaning gold.
The cavitator represents a row of pipes with different diameter with embedded nozzles, carrying out the water supply for uniform washout. This is the very advantage of the cavitator in comparison with a hydro monitor, purpose of which is not the uniform, but the pointed washout of rock by means of single stream of water. The cavitator is installed before the gates section of the complex with the view of already washed rock supply to gates. There are concentrators of the current unloading (CCU) installed for the catching of fine gold after gates. In the basis of results of grain size classification of sands of the deposit CCUs are equipped by mesh with various sizes. The maximum extraction of hard-cleaning gold can be achieved by means of application of the lead «heavy bed» in CCUs as per the set configuration. Concentrators in this complete set are unpretentious in terms of operation and do not demand the constant presence of highly qualified specialists.
In case of the presence of large share of hardly extractable gold in the washed-out sands the washing complex can be completed by jigging machines of DJM type (diaphragm jigging machines) application of which improves the extraction of hard-cleaning gold even more, minimizing losses while washing to the lowest rate.
In general the universality of application of washing and screening complex (WSC) is achieved by means of use of the full functional system of operation of the equipment consisting the following:
- compulsory regulation of the washout of soil at the top deck of screen;
- distribution of the effluent stream at the expense of correct geometry of gates section (use of stream dividers system of «pants» type) which allows the reduction of effluent stream speed, thereby improving the extraction of hard-cleaning gold;
- application of the cavitator and jigging machines.
Correct selection of pumps and pressure regulation allow to achieve washing of any clay.
Result
The first thing to note is the high proportion of fine gold recovery — 85% of the size of less than 0.5 mm. Fine gold up to 0.01 mm is captured from the gateways without using of additional extraction by jigging machines of the MOD type. Thus, it is possible to speak about efficiency of the washing complex in terms of extraction of hard-cleaning gold with fraction up to abnormally small sizes.
All modifications and variants of the washing and screening complex are tested by practical application and can be completed depending on mining-and-geological conditions and characteristics of deposits, as well as wishes of the Customer.
Personal acquaintance with the technology and results of WSС operation is possible by ordering a familiarization trip to the deposit of «Gold Mine Technology» JSC at our specialists via phone: +7 (391) 219-29-60, e-mail gmt@goldmine.gold or at the website.
