Background technology
The reserves of refractory gold ore account for 60% of world's gold mine total reserves, and along with being prone to soak the day by day exhausted of gold ore resource in the world, the extraction of gold progressively turns to the indissoluble gold ore deposit.This type gold mine mainly is because the existence of harmful elements such as charcoal sulphur arsenic influences the existence of the leaching, particularly organic charcoal of gold, does not also have a kind of efficient ways so far in order to improve the recovery of this type gold mine gold.
The tradition roasting oxidation method is the difficult-treating gold mine pretreatment process of comparative maturity, its parcel gold in pyrite, the mispickel sulfides that can dissociate, and can comprehensively reclaim sulphur and arsenic wherein.But it is wayward that its shortcoming is a roasting process, is not that " underburnt " is exactly " burning ", is difficult to guarantee that output is suitable for the high-quality calcining of cyanide gold-leaching.Particularly for the high material of carbon containing, be difficult to burn fully whole carbon in the calcining process, possibly make the surplus carbon ratio in the calcining not have more activity before the roasting, it is stronger to inhale gold (robbing gold) ability, makes the gold leaching rate after the roasting maybe be lower.For containing the high gold-bearing material of arsenic, if do not add reductive agent (like coal), gold is very big with the loss of arsenic evaporable in the roasting; If add an amount of reductive agent, will influence follow-up cyaniding again and leach.So traditional roasting oxidation method is handled difficult-treating gold mine has very big shortcoming.
Hot-pressure oxidation technology also is one of difficult-treating gold mine pretreatment process, and it is divided into two kinds of acid hot-pressure oxidation method and alkaline hot-pressure oxidation methods.Alkalescence hot-pressure oxidation method is owing to be only applicable to carbonate content height, refractory gold ore that sulfide content is low, thereby comparatively speaking, the application of acid hot-pressure oxidation technology is comparatively extensive.The advantage of acid hot-pressure oxidation method is that the oxidation products of sulfurous iron ore and mispickel all is soluble; Therefore, how gold grain carefully all can be dissociated, thereby the leaching recovery of gold is higher; Many golden ore concentrate hard to treat after Pretreatment with Pressurized, the gold leaching yield have up to more than 98%.This technology can directly be handled raw ore simultaneously, and this is more effective for the Gold Ore that is not easy to floating and enriching.But the shortcoming of this technology is: Equipment Design and material require very high, because the anticorrosion problem of HTHP operation and equipment can be brought very high safety risk, compare with biological oxidation process, and the requirement of operation and maintenance level is higher; Moreover initial cost is big, thereby generally believes to have only the construction large-scale plant, economically just relatively rationally.
In addition, acid hot-pressure oxidation method is the same with bio-oxidation technology, and major ingredient ferro element in the material and arsenic etc. are all soluble in water basically, has increased many pressure for the processing of factory effluent, has also increased processing costs.Technology is also selective to material, and concerning the variety such as " poor, thin, assorted " of present difficult-treating gold mine resource, use and also receive certain limitation, to the processing of carbonaceous gold ore, weak effect.
Bio-oxidation technology also is one of difficult-treating gold mine pretreatment process, is that another has the pretreatment technology of powerful vitality after roasting oxidation technology and hot-pressure oxidation technology.But also there are many weakness, as: oxidization time is long, and pulp density is low, needs big volumetrical to stir oxidation trough; Oxidation needs high oxygen-supplying amount, and the blower fan energy expenditure is high; Oxidation heat liberation during works better, generally needs the cooling cooling, consumes extra energy; If occur in operation once " mishandle ", bacterium may be dead, and this needs could recover the living weight of bacterium in several weeks; Material is also had selectivity highly, and application also is very limited, to the processing of carbonaceous gold ore, weak effect.
Summary of the invention
The object of the present invention is to provide a kind of indissoluble gold ore deposit to put forward the process method of gold, with solve the complicated operation, the cost that exist in the gold extracting method in the past high, pollute big, put forward problems such as golden rate is low.
The process method that gold is carried in a kind of indissoluble gold provided by the invention ore deposit is used for handling and contains charcoal, sulfur-bearing, treating refractory As-containing gold ore; Utilize the sulfuric acid of output in the conventional sulfurization roasting technology; Burning slag to conventional sulfurization roasting carries out the acid roasting oxidation of secondary low temperature, carries out medium temperature roast after the acid roasting of secondary low temperature and decomposes vitriol recovery sulphur trioxide and sulfurous gas, carries out cyaniding afterwards and leaches; Make gold in the difficult-treating gold mine by high efficiency extraction, concrete technological process is as shown in Figure 1:
Step 1: with sulfur-bearing>10% indissoluble gold green ore or gold ore carry out conventional sulfation oxidizing roasting, the sulfation calcining, simultaneously from the sulfurization roasting flue dust with white arsenic and sulfur dioxide recovery;
Step 2: above-mentioned sulfation calcining is wetting with sulfuric acid, and wherein, the mass ratio of sulfuric acid and water is 1:0.5 ~ 0.7, and the mass ratio of calcining and water is 1:0.3 ~ 0.45; Wherein said sulfuric acid is preferably processed by the sulfurous gas that obtains in the step 1, thereby realization technology is used the self-sufficient of acid, and discharge tail gas in the process of conventional sulfuric acid oxidation roasting is carried out off gas treatment, qualified discharge by vitriol works's technological standards simultaneously;
Step 3: the sulfation calcining after wetting is sent into the oven dry of dissepiment roaster, carry out the acid roasting oxidation of secondary low temperature, wherein; The dissepiment roaster is from burner to stove tail; The low earlier back of temperature is high, and variation range is 150 ~ 300 ℃, generally dries 90 ~ 120min; Concrete how much consuming time, should confirm according to the character of different material;
In the low-temperature bake process, the material dehydration, dilute sulphuric acid changes the vitriol oil into; Under near vitriol oil boiling temperature (338 ℃ of vitriol oil boiling points), the vitriol oil has extremely strong oxidisability, can the most metal suboxides of oxidation, sulfide, organism etc.; Even wood chip also can be oxidized to carbon, be oxidized to carbonic acid gas then, therefore; Multiple MOXs such as the iron in the material, copper, lead, zinc, nickel, cobalt, antimony all can be oxidized to vitriol by sulfuric acid under near its boiling temperature; Secondly, original residual active carbon, arsenic and sulfide etc. of having more also are oxidized to CO in the sulfation calcining
2, As
2O
3And vitriol, thereby in the sulfurization roasting process that further dissociates not by dissociative and the parcel gold that produces because of burning is new, wherein the thermal source of dissepiment roaster derives from the waste heat of vitriol works;
Step 4: the product behind the above-mentioned secondary low-temperature bake is put into dryer continue baking, decompose vitriol, and volatilize unnecessary acid, wherein, storing temperature is 550 ℃ ~ 600 ℃;
After the acid roasting of secondary low temperature; Then in being higher than the inherent dryer of 550 ℃ ~ 600 ℃ TRs of iron sulfate and other metal sulfate dissociative, continue roasting and carry out the sulfation decomposition; Usually the time is 60min, because most metal vitriol dissociative temperature is 550 ℃ ~ 600 ℃, so in this TR, can not produce new inclusion; Thereby, make the vitriol of iron dissociate into Fe
2O
3, other metal sulfate also dissociates and discharges SO
3The acid that roasting volatilizes (contains SO
3, SO
2) and the SO that decomposites
3(contain SO
2) return vitriol works's relieving haperacidity, recycle reduces and pollutes, and has also reduced cost simultaneously;
Step 5: the product after will drying adds water sizes mixing, and the back of sizing mixing is finely ground in immersing-by-grinding machine 90% ~ 95% or more passes through 400 orders, and then adds quicklime and sodium cyanide is sized mixing; After adjusting pH value is 10 ~ 11; Carry out the cyaniding of gold and handle, finally carry gold and finish, wherein; Described cyaniding is handled can conventional cyaniding 24h or carry out pressure cyanide 2h (reaction kettle 0.8MPa), and the leaching yield of gold generally all can reach more than 90% ~ 95%;
After roasting finishes, add water and size mixing, its objective is, can from infusion, reclaim, like copper etc. for when the association valuable element has recovery value in infusion;
The water logging slag is finely ground to 400 orders through tower grinding-leaching mill and accounts for more than 90% ~ 95%, and this process can further dissociate and be wrapped in the gold in the gangue.
In sum, the process method of gold is put forward in a kind of indissoluble gold provided by the invention ore deposit, and the method that adopts sulfurization roasting to combine secondary low-temperature bake and sulfation to decompose is handled the indissoluble gold ore deposit.The employing of the acid roasting of secondary low temperature; Make the unitary technology control of sulfurization roasting less demanding; No matter the sulfurization roasting unit is " underburnt " or " burning "; The decreasing ratio of also not being afraid of sulfurization roasting unit arsenic, sulphur, carbon is high and not high, also no matter in the sulfurization roasting unit ferro element mainly be with Fe
2O
3Form exists still with Fe
3O
4Form exist; Cyaniding leaching yield influence to gold is all little; Further processing and sulfation through the acid calcining process of follow-up secondary low temperature are decomposed; Can both obtain high cyaniding and leach the recovery, its overall process is for adopting sulfurization roasting, and---cyanidation gold-extracted works continuously, and makes the indissoluble gold that is wrapped in carbon, arsenic, the sulphur by high efficiente callback to burn the acid roasting of slag secondary low temperature---middle temperature sulfation is decomposed---.
The process method of gold is put forward in order to improve the protection to environment in indissoluble gold provided by the invention ore deposit, can also do following improvement:
1, the off gas treatment after the sulfurization roasting relieving haperacidity on the basis of existing conventional vitriol works tail gas treatment device, increases the same treatment facility of one ~ secondary, the waste gas qualified discharge more.
2, the arsenic-containing material in sulfurization roasting receipts arsenic condensing chamber and the gas cleaning unit can adopt the outer heating equipment of negatively pressurized static of standard universal to be heated to 150 ℃, makes the arsenic distillation and is purified to the pure As more than 99.6%
2O
3Product, the residual slag after then arsenic being reclaimed passes on the golden system that selects.
3, the mine tailing after cyanidation gold-extracted is through SO
2-air oxidation process is handled, and eliminates after the prussiate, can be through dehydrating processing, and the cement mill is given in export trade, or manages brick field brickmaking export trade by oneself.
4, material was removed most base metals through water-immersion system before getting into the cyaniding leaching.In leaching vat or reaction kettle, carry out cyaniding and leach, the prussiate consumption is low, and leach liquor can recycle for a long time.
5, the acid waste water that produces in the technological process can be used as the acid roasting batching of secondary low temperature water, practices thrift the sulfuric acid consumption, also need not efflux.
6, other water coolant, dash ground water etc. and can realize that also factory's internal recycle uses.
In sum, the process method that gold is carried in indissoluble gold provided by the invention ore deposit can reach the purpose of not having useless production, and is environmentally friendly.
Indissoluble gold provided by the invention ore deposit is put forward the process method of gold and is compared with pressure oxidation method, bacterial oxidation method, and it is simple to have a technical process, less investment; Working cost is low; Convenience operation, particularly secondary low-temperature bake, it has made full use of the sulfuric acid of producing in the leading portion sulfurization roasting process and has carried out the secondary exhaustive oxidation; Gold is dissociated, harmful elements such as the charcoal that the gold of eliminating the effects of the act more up hill and dale leaches, sulphur, arsenic; And then warm sulfation is decomposed in carrying out, and decomposes vitriol and volatilizes unnecessary acid, passes through fine grinding then; Realize the high efficiency extraction of gold, in addition, the present invention also is unified in realization under the normal pressure with the advantageous properties of roasting oxidation method and acid hot-pressure oxidation method; The compatible advantage of two kinds of methods, operational condition is relatively gentleer, and speed of response is fast; The technology investment expense is low, and productive expense is suitable, environmental friendliness; Be easy to realize suitability for industrialized production, this method also is suitable for the pre-treatment that other sulfur-bearing contains type difficult-treating gold mines such as arsenic, and the hydrometallurgy system that is suitable for other roasting, leaching.
Embodiment
Embodiment 1:
Yunnan Zhen Yuan gold floatation concentrate contains golden 35.86g/t, sulfur-bearing 15.11%, contains arsenic 0.70%, carbon containing 4.83%, and fineness is 70%-37um.The granularity of gold is fine, is mainly the sulfide parcel, accounts for 85.69%, and the exposed gold of monomer accounts for 10.16%, and gangue parcel gold accounts for 4.15%, and the maximum goldc grains of finding is 0.0085mm under the mating plate mirror, and is wherein many at 0.002 ~ 0.005mm.Organic carbon content has very strong " robbing gold " ability up to 1.11% in the sample ore.Direct cyaniding 48h, the leaching yield of gold is merely 1%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 867g behind the normal temperature, burning the slag productive rate is 86.7%.
Claim to burn slag 433.5g, use 250gH
2SO
4(about 136ml) and water 150ml size mixing, and carry out low-temperature bake afterwards.When 150 ℃ of muffle furnace furnace temperature, go into stove baking 30min, bake block back shovel when slip and move and is divided into fritter, be warming up to 200 ℃ and 250 ℃ again and respectively toast 30min.
Behind the low-temperature bake, be warming up to 550 ℃~600 ℃ again, continue baking 60min.Be cooled to room temperature then, the heavy 422g of slag is by raw material slag productive rate 84.4%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2Cyanidation tailings gold grade 2.39g/t, the leaching recovery 94.37% of gold.
Embodiment 2:
Chang'an, Yunnan gold floatation concentrate contains golden 37.60g/t, contains arsenic 3.47%, sulfur-bearing 22.82%.The disseminated grain size of gold is atomic thin, all less than 10um, occupies the majority with 2~10um basically.Gold is irregular granular filling in mispickel intergranular crack or the mispickel edge, or is distributed in the pyrite crack with pyrite adhesion embedding, or is fine granular inclusion and is contained in the quartz.Direct cyaniding 48h, the leaching yield of gold only 13.7%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 920g behind the normal temperature, burning the slag productive rate is 92.0%.
Claim to burn slag 460g, use 250gH
2SO
4(about 136ml) and water 150ml size mixing, and carry out low-temperature bake afterwards.When 150 ℃ of muffle furnace furnace temperature, go into stove baking 30min, bake block back shovel when slip and move and is divided into fritter, be warming up to 200 ℃ and 250 ℃ again and respectively toast 30min.
Behind the low-temperature bake, be warming up to 550 ℃~600 ℃ again, continue baking 60min.Be cooled to room temperature then, the heavy 449g of slag is by raw material slag productive rate 89.8%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2Cyanidation tailings gold grade 2.38g/t, the leaching recovery 94.32% of gold.
Embodiment 3:
Guangxi golden tooth gold floatation concentrate contains golden 53.60g/t, sulfur-bearing 32.28%, contains arsenic 7.51%, carbon containing 0.86%.Direct cyaniding 48h, the leaching yield of gold is 53.2%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 858g behind the normal temperature, burning the slag productive rate is 85.8%.
Claim to burn slag 429g, use 250gH
2SO
4(about 136ml) and water 150ml size mixing, and carry out low-temperature bake afterwards.When 150 ℃ of muffle furnace furnace temperature, go into stove baking 30min, bake block back shovel when slip and move and is divided into fritter, be warming up to 200 ℃ and 250 ℃ again and respectively toast 30min.
Behind the low-temperature bake, be warming up to 550 ℃~600 ℃ again, continue baking 60min.Be cooled to room temperature then, the heavy 413g of slag is by raw material slag productive rate 82.6%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2Cyanidation tailings gold grade 1.78g/t, the leaching recovery 97.26% of gold.
Embodiment 4:
Lijing Ning Lang county, Yunnan ancient times high arsenic matte slag, contain golden 36.58g/t, argentiferous 230g/t, sulfur-bearing 16.15%, contain arsenic 31.33%, cupric 6.43%, leaded 2.18%, contain zinc 3.59%, iron content 36.56%.
Get siccative 1000g, be finely ground to 90% through 200 orders.When 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 723g behind the normal temperature, burning the slag productive rate is 72.3%.
Claim to burn slag 361.5g, use 250gH
2SO
4(about 136ml) and water 150ml size mixing, and carry out low-temperature bake afterwards.When 150 ℃ of muffle furnace furnace temperature, go into stove baking 30min, bake block back shovel when slip and move and is divided into fritter, be warming up to 200 ℃ and 250 ℃ again and respectively toast 30min.
Behind the low-temperature bake, be warming up to 550 ℃~600 ℃ again, continue baking 60min.Be cooled to room temperature then, the heavy 352g of slag is by raw material slag productive rate 70.4%.Add the water logging copper afterwards, the water logging pulp water is washed the back under 50% ore milling concentration, in tower grinding-leaching mill, is finely ground to 400 orders and crosses 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2Cyanidation tailings gold grade 1.18g/t, the leaching recovery 97.73% of gold.
Embodiment 5:
Guizhou carbonaceous gold floatation concentrate: contain golden 46.65g/t, sulfur-bearing 24.30%, carbon containing 2.25%, contain arsenic 2.30%, directly cyaniding is 48 hours, and the leaching yield of gold is merely 14.7%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 934g behind the normal temperature, burning the slag productive rate is 93.4%.
Claim to burn slag 467g, use 250gH
2SO
4(about 136ml) and water 150ml size mixing, and carry out low-temperature bake afterwards.When 150 ℃ of muffle furnace furnace temperature, go into stove baking 30min, bake block back shovel when slip and move and is divided into fritter, be warming up to 200 ℃ and 250 ℃ again and respectively toast 30min.
Behind the low-temperature bake, be warming up to 550 ℃~600 ℃ again, continue baking 60min.Be cooled to room temperature then, the heavy 452g of slag is by raw material slag productive rate 90.4%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2Cyanidation tailings gold grade 1.97g/t, the leaching recovery 96.18% of gold.
Comparative Examples 1:
Yunnan Zhen Yuan gold floatation concentrate contains golden 35.86g/t, sulfur-bearing 15.11%, contains arsenic 0.70%, carbon containing 4.83%, and fineness is 70%-37um.The granularity of gold is fine, is mainly the sulfide parcel, accounts for 85.69%, and the exposed gold of monomer accounts for 10.16%, and gangue parcel gold accounts for 4.15%, and the maximum goldc grains of finding is 0.0085mm under the mating plate mirror, and is wherein many at 0.002 ~ 0.005mm.Organic carbon content has very strong " robbing gold " ability up to 1.11% in the sample ore.Direct cyaniding 48h, the leaching yield of gold is merely 1%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 867g behind the normal temperature, burning the slag productive rate is 86.7%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2, the leaching recovery 36.03% of gold.
Comparative Examples 2
Chang'an, Yunnan gold floatation concentrate contains golden 37.60g/t, contains arsenic 3.47%, sulfur-bearing 22.82%.The disseminated grain size of gold is atomic thin, all less than 10um, occupies the majority with 2~10um basically.Gold is irregular granular filling in mispickel intergranular crack or the mispickel edge, or is distributed in the pyrite crack with pyrite adhesion embedding, or is fine granular inclusion and is contained in the quartz.Direct cyaniding 48h, the leaching yield of gold only 13.7%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 920g behind the normal temperature, burning the slag productive rate is 92.0%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2, the leaching recovery 73.46% of gold.
Comparative Examples 3
Guangxi golden tooth gold floatation concentrate contains golden 53.60g/t, sulfur-bearing 32.28%, contains arsenic 7.51%, carbon containing 0.86%.Direct cyaniding 48h, the leaching yield of gold is merely 53.2%.
Get gold ore (drying) 1000g, when 400 ℃ of muffle furnace furnace temperature, go into stove, begin to be warming up to 650 ℃ behind the 30min, crack fire door (stir and turn over breeze three times), temperature control roasting 60min midway.Be cooled to that weight is 858g behind the normal temperature, burning the slag productive rate is 85.8%.Add water afterwards, under 50% ore milling concentration, in tower grinding-leaching mill, be finely ground to 400 orders and cross 95%.Add CaO then and sodium cyanide is sized mixing, slurry pH about 10.5, cyanogen root concentration 1 ‰, air agitation leaches 48h, replenishes a small amount of (0.5kg/t) H midway
2O
2, the leaching recovery 76.31% of gold.