The importance of the properties of the two zones, which include pulp hydrodynamics, froth bubble coalescence rate, water overflow rate, air recovery, etc. The properties are depending not only on the type and concentration of the frother but also on the nature and amount of the particles present in the flotation system, and as well as the frother-particle interactions and potentially of bubble-particle interactions. To date, there is no specific criterion to quantify pulp and froth properties through the interactions between frothers and particles because the various related mechanisms occurring in the pulp and froth are not fully understood. Linking the properties to the metallurgical performance is also challenged. In order to better understand the effect of these issues in flotation, in this review paper, the past and recently published articles relevant to characterizations of pulp and froth properties are widely reviewed; the findings and the gap of knowledge in this area are highlighted for further research. Related Articles:.
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Deposits are also getting more remote and more difficult to access. Mining chemicals form a crucial part of the chain, and are absolutely fundamental to maximising recovery. The industry has both commodity and specialised chemicals — but a major issue is the level of investment required by key players to develop new and more advanced solutions, and if this will even happen to the degree necessary if the mining industry is not willing to invest in their use versus cheaper but less effective and less environmentally friendly alternatives.
Market players The market for mining chemicals supply ranges from focussed divisions of global companies such as Clariant, BASF now owns former Cognis and CIBA chemicals businesses and Cytec to more specialised dealers and suppliers of mining chemicals, but who also operate globally, such as SNF Flomin and Cheminova; and finally distributors, which are very numerous in local markets but may be sizeable in their own right in particular mining regions.
The global groups have the advantage of being able to provide strategically located offices in the major mining regions to provide the best possible allow local support, which may include manufacturing, testing laboratories and service personnel. However, most of the Chinese-made mining chemicals are not sold directly by manufacturers but almost exclusively through distributors.
As a result of the market division between lower cost product lines and more advanced chemistries, it is also true that some players have withdrawn from the market altogether, or have chosen to focus on particular areas. The downside to bulk low cost supply is a constantly changing environment at the primary feed stock supply sources, with a resulting lack of quality consistency in some cases. This trend will probably continue. This has affected the established suppliers, by causing them to withdraw from the manufacture and sale of some reagents.
For example, both Cytec and Clariant have withdrawn from offering xanthates. Only a few suppliers offer the entire range of mining chemicals.
Niche local suppliers are able to offer some chemicals in their respective countries and do quite well. Some chemistries cannot be economically produced by all players and as a result, some suppliers have unique advantages and are able to offer their products at substantial premiums. That said, new entrants in other chemicals for mining, especially from China, is still driving pricing and profitability lower.
Chinese and Indian suppliers may also have a future advantage due to lower standards for chemical production. Commodity versus specialised Reagent chemicals are the key to the flotation process as they actively separate the desired mineral particles from the other minerals, create the bubbles that transport them, and control the overall pH of the tank at a range where the reagents work most effectively.
The main chemical groups divided by application are collectors, which act as surfactants in the flotation cell and adsorb to the surfaces of the valuable mineral particles and make them hydrophobic water repellant and frothers, which have the effect of producing stable bubbles in the cell for these hydrophobic particles to attach themselves to. Other types of chemicals used include depressants, which form a polar chemical envelope around particles and depress the effect of any hydrophobic gangue minerals in the ore that would otherwise report with the froth along with the desired metallic mineral particles.
There are also differential or reverseflotation systems, where depressants are used to hold down the desired mineral while floating the undesirable gangue. Aside from flotation reagents, the industry includes the supply of extraction chemicals such as extractants and diluents; thickeners flocculants and coagulants used either as part of a process to thicken tailings for disposal or in the refining process; bulk acids such as sulphuric acid used in heap leaching; cyanide for gold processing; anti-scaling chemicals and dust suppressants amongst others.
By far the most widely used reagent collector compound is the xanthate family. Predecessors of Clariant, Cytec and Dow were all involved in the development and sales of these pioneering chemicals in mining. In some areas they have performed better than other chemistries. Even though there are quality variations among suppliers, customers view them as commodities and bargain for lower prices.
The difficulties in switching are compounded by the fact that engineering companies specify xanthates to be lab tested and later used in the mine. As such, budgets do not always allow for a wider range of reagent testing for optimal performance. Investment in new reagent innovations is the key to being able to liberate and achieve economically viable recovers in the future. There is a symbiotic relationship between the mining operations and the reagent manufactures and needs to be recognised.
If the trend towards commoditisation of mining reagents continues, the product margins that allow for new research will dry-up. This is where the mining companies can help to support their own futures. New advances have been introduced by Cytec in flocculant technology, sodalite scale inhibition, promoters and collectors and solvent extraction solutions.
This is a novel strategy for mineral flotation that combines an expert system, proprietary reagent blends and expertise and insights to generate consistent, quantifiable improvements in metallurgical, operational and financial performance. Ores differ widely globally and often in small, but significant ways. For example, Codelco Andina and Anglo American Los Bronces are on the same mineral belt and one opposite sides of the same mountain.
Tailoring the right reagents for a specific ore and operation may only make a 0. Mining reagents cannot be treated as an ingredient in a finished product; core characteristics change which affect the composition of the feeds and may even impact the process water conditions. As a result, reagents can bring significant benefit to the performance of the mine or refinery when used wisely.
Each mine is unique in the type of ore and challenges in treatment. Many times advanced methods for solving increasingly difficult problems from precious, base and industrial mineral operations are needed.
Treatment programs and reagents will differ depending on many factors. Although there are no generic chemical solutions that can be used to treat a particular metal or minerals due to the complex interaction of chemical, physicalmechanical and operational factors and the different needs of the operations, there are reagents that act as a good starting point such as AEROPHINE for copper-gold ores, AERO XD for flotation of copper ores containing iron sulphides under mild alkaline conditions, and AERO MAXGOLD as a precious metal collector.
But each mining operation requires a unique optimized chemical solution. One customer with two operating mills uses xanthates while the other uses dithiophosphates DTPs. Some metallurgists may also have preference to oily collectors versus water soluble ones.
There may be troublesome impurities present such as clays, which require special reagents. For each ore type — mineralogy and geology — FloMin offers several reagents based on prior success.
Other operating factors such as ore changes, grinding, pH, addition points, and overall plant design contribute to performance. The suppliers have to constantly evaluate all transportation possibilities that provide the best economy of scale but that also deliver products in a manner that customers expect and on time.
Xanthates are supplied as powders and pellets in plywood covered bulk bags or drums, but for environmental and safety reasons, pellets are preferred. Dithiophosphates are supplied as liquids, while thionocarbamates as liquid and oxide collectors as liquids or pastes. Frothers are all supplied as liquids. Local infrastructure includes manufacturing, testing laboratories and service personnel. Each year presents different challenges including availability, costs and reliability of transportation carriers particularly to remote and undeveloped geographies.
It is important to understand and manage each situation to ensure quality service is not compromised. Most of the mines are located in remote regions of continents and most mining reagents like xanthates are hazardous cargo. More shipping lines are making it difficult to ship xanthates by sea. Customers are also requesting pricing based on delivery to the minesite including warehousing. This is also a major challenge for global suppliers. Over the last few years, requests for more environmentally sensitive reagents have become more common from the mining companies.
This is change and is ahead of government regulations. Projects have even held-up due specifically to environmental concerns. Also, while ores are becoming increasingly difficult to treat, environmental regulations are becoming more stringent. Water use or more importantly water conservation is becoming a major concern. The industry is looking to the mining chemical manufacturers to develop speciality reagents that can meet their needs in treating difficult ores and to allow them to address the environmental and resource challenges.
Innovative chemistries are being introduced that allow regulations on waste water discharge and emission to be met and are cost effective from a total treatment cost perspective. Clariant Clariant has a long history of providing collectors Flotinor, Hostaflot , depressants Flotol and frothers Flotanol, Montanol for the mining flotation process.
It also supplies the Arkomon range of products for dust control. The company describes its expertise as focussing on meeting the specific needs of customers wherever they are located, which includes iron ore in Brazil, sulphide copper ores in Chile and Peru, tin in Australia and rare earths in North America.
However, whatever the ore demands, Clariant states that it is able to provide local support and expertise wherever the customer is located. This location only deals with mining and does not support other businesses. Clariant Mining Solutions was founded in and is a business unit of Clariant AG; which is the direct descendant of the multinational chemical companies, Sandoz and Hoechst.
This includes expand its operational reach, broadening and deepening its product portfolio and enhancing technical and service offerings through the addition of skilled and knowledgeable personnel who are experts in their fields. Gould is very upbeat on the current market. These are performance, value, service and security of supply. Our expertise is in three main areas of mining: aluminum processing, mineral processing and solvent extraction.
In our main products we are the global leader both in terms of application expertise and market share with on-site technical assistance provided on a global basis.
Our customers expect and receive application support as an included element of the Cytec offering. Other proprietary tools include diagnostic software, statistical process analysis and design, as well as specifically developed laboratory and field tests; many of which have become industry standards.
These extractants provide plants with enhanced kinetics, productivity and throughput. In aluminum processing, its products range from bauxite handling aids to hydrate dewatering, Cytec technologies bring new efficiency to all aspects of the Bayer process used in alumina production. One area of progress has been in xanthate alternatives. Based on a desire to provide the industry with sustainable solutions , Cytec has developed the XR Series of xanthate replacement products that exhibit a metallurgical profile very similar to that of the xanthates while mitigating the Safety Health and Environmental SHE concerns.
In addition, this new series of products is cost competitive compared to xanthates. Solving customer needs with novel technology does not necessarily mean higher cost reagents. Cytec focuses on solving our customer needs while offering an attractive value proposition. It maintains an inventory of a wide range of frothers from MIBCs to glycol ethers to specialty alcohol blends.
Industrial minerals markets are supplied with fatty acids, petroleum sulfonates, surfactants, dust control agents, defoamers, and dewatering aids. The parent company SNF is the largest producer of water soluble polymers worldwide including flocculants, dispersants and coagulants as well as feed equipment. FloMin has employed some novel approaches to blending existing chemistries have yielded some very impressive products. A large impact has been made by customising frothers rather than using standard MIBC or glycol ethers.
Also, there is an emphasis on placing alternative collectors inside of xanthate pellets. We expect to see growth in this area. In the past it was perceived that only a handful of companies were the only credible global supplier of specialty promoters. Successful implementation of FloMin reagents in new mines and switched sourcing from some large mines has given us invitations from others. This includes anionic collectors, cationic collectors, frothers, pH modifiers, defoamers, polymers, rheology modifiers and depressants.
In this niche, it is the market-leader. These industrial minerals also require customised chemical suite solutions. For example for phosphate ores, Florida phosphate is sedimentary with silica and clay as main gangue minerals, for which we use anionic collector to float the phosphate, then use cationic collector to further lower the silica content from the rougher concentrate.
Deposits are also getting more remote and more difficult to access. Mining chemicals form a crucial part of the chain, and are absolutely fundamental to maximising recovery. The industry has both commodity and specialised chemicals — but a major issue is the level of investment required by key players to develop new and more advanced solutions, and if this will even happen to the degree necessary if the mining industry is not willing to invest in their use versus cheaper but less effective and less environmentally friendly alternatives. Market players The market for mining chemicals supply ranges from focussed divisions of global companies such as Clariant, BASF now owns former Cognis and CIBA chemicals businesses and Cytec to more specialised dealers and suppliers of mining chemicals, but who also operate globally, such as SNF Flomin and Cheminova; and finally distributors, which are very numerous in local markets but may be sizeable in their own right in particular mining regions. The global groups have the advantage of being able to provide strategically located offices in the major mining regions to provide the best possible allow local support, which may include manufacturing, testing laboratories and service personnel. However, most of the Chinese-made mining chemicals are not sold directly by manufacturers but almost exclusively through distributors. As a result of the market division between lower cost product lines and more advanced chemistries, it is also true that some players have withdrawn from the market altogether, or have chosen to focus on particular areas.
mining chemicals handbook