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By B. Tiryaki

Longwall shearers usually suffer from excessive pick and pickholder consumptions and severe wear of the back plate of the clearance ring section of shearer drums. In practice, most of the drums were seen to be withdrawn from the face due to the abovementioned problems, while vane picks and their holders were intact due to the improper lacing design of the clearance ring picks. However, few underground investigations and their results on the effect of lacing arrangement of clearance picks on the service life of shearer drums have been published. Nevertheless, the pick consumption characteristics of shearer drums were not investigated in detail, since these are fewer pick consumptions with shearers when compared to roadheaders. This paper is concerned with the comprehensive in situ trials on the effect of lacing of clearance ring picks on the lifespan of shearer drums, and the pick consumption characteristics of longwall shearers at Cayirhan Coal Mine in Turkey. The lifespan of shearer drums employed with shearers in this mine increased 70 per cent, while the consumption rate of clearance ring picks decreased threefold through using an alternative lacing for clearance picks, indicating the significance of utilizing proper design techniques for clearance ring picks for the service life of shearer drums. Statistical analyses carried out, using the raw pick consumption data, implied that the clearance ring picks experienced much higher loads than vane picks, revealing that special attention must be paid to designing clearance ring picks. An average maximum consumption value of 41 was determined for clearance ring picks, with corner-cutting picks having the most replacements, while it was 35 for vane picks, on three-day based pick replacements.

Jan 1, 2004

By K. U. Kainer, A. Stark, D. Tolnai, M. Hehenberger, C. L. Mendis, N. Schell, N. Hort

Samples of an as extruded Mg-6Zn-0.6Zr-0.4Ag-0.2-Ca (wt.%) alloy was compressed at room temperature and at 250°C. The in situ deformation tests were performed at the P07 (HEMS) beamline of PETRA III, DESY, with a modified DIL 805 A/D dilatometer with to Kapton windows on the sides and the induction coil opened for the beam to transmit the sample. The deformation rate was 10-3 s-1 the samples were deformed to failure. The diffraction patterns were recorded every 3 s with a Perkin Elmer 1621 Flat Panel Detector. The results reveal that different deformation mechanisms are activated during compression at a given strain value. At room temperature twinning is the dominant deformation mechanism, while at elevated temperature dynamic recrystallization occurs while the contribution of twinning to deformation is significantly reduced. The compressed samples were further investigated with conventional metallography and SEM-EBSD to determine the volume fraction, the type of twinning and the strain retained within the grains. The parallel testing of pure Mg samples under the same conditions allows comparison of the compression behaviour of the ZKQX alloy with Mg.

Jan 1, 2014

By Napisporn Memongkol

Syntheses of Al-TiC-Al2O3 and Al-SiC-Al2O3 composites were obtained in situ by carbothermal reduction of mixtures of Al powder, TiO2 powder and activated carbon powders and Al powder, SiO2 powder and activated carbon powders. The reductions were carried out in a horizontal tube furnace under flow of inert gas. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The synthesized products were mixtures of aluminum reinforce with titanium carbide and alumina and aluminum reinforce with silicon carbide and alumina. The effect of the reaction temperature (1000 o C ? 1200 o C) and condition of precursors on the Al powder, TiO2 powder and activated carbon powders and Al powder, SiO2 powder and activated carbon powders were investigated using XRD and SEM method. The synthesized products showed those composites with aluminum matrix and titanium carbide and alumina as reinforced phases and aluminum matrix and silicon carbide and alumina as a reinforced phase was formed.

Jan 1, 2006

By Sutham Niyomwas

Silicon-Silicon Carbide (Si-SiC) composites were synthesized by self-propagating high temperature synthesis (SHS) from a powder mixture of SiO2-C-Mg. The reaction was carried out in a SHS reactor under static argon gas at a pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The effects of silica sources and carbon mole ratio in precursor mixture on the Si-SiC conversion were investigated using X-ray diffraction and scanning electron microscope technique. The as-synthesized products of Si-SiC-MgO powders were leached with 0.1M HCl acid solution to obtain the Si-SiC composite powders.

Jan 1, 2009

By Malcolm Scoble, Jean-Marc Robert, Luciano Piciacchia

"An approach to the in situ testing of mine backfills is outlined. It has been developed to provide a measure of the effective strength and stiffness of such materials after placement in stopes. This paper is based upon recent field studies undertaken at five Quebec mines. Details of the selected instrumentation, supporting equipment and testing procedures are reviewed. The mechanical behaviour of the backfills is reported and related to their physical properties. This approach represents an economical, simple and reliable means to assess the mechanical characteristics of backfill materials as an aid to both mine design and placement quality control. IntroductionDevelopments in backfill and mining method technology are creating a pressing need to develop effective techniques for characterizing the physical and mechanical properties of backfill in situ, rather than relying on traditional laboratory testing. The development of bulk mining methods is creating the requirement to more fully understand the nature of exposed fill faces to design for stability in pillar recovery operations. Other backfill technological developments currently receiving widespread attention are high density placement and the use of alternative additives to Portland cement. In Canada, U.S.A. and South Africa attention is also being placed on employing backfill to alleviate rockburst hazards(1,2.3l. In situ testing offers the potential to measure the geomechanical properties of backfill once placed in stopes , in order to assess its actual role in pillar recovery and ground support. Similarly, it offers the ability to provide some quality control during backfill placement. This role is seen as becoming increasingly important with the growing recognition of the need to pay greater attention to the mode of placement, which governs segregation and variation in the properties actually achieved by the backfill after placement."

Jan 1, 1987

By D. E. Munson

The Waste Isolation Pilot Plant (WIPP) Project was established in 1975 by the Department of Energy (DOE) under Public Law 193 to develop the necessary technology for safe disposal of radioactive wastes from the defense programs of the U.S. The technology development involves extensive theoretical, numerical, and laboratory programs, as well as construction of the WIPP facility in southeastern New Mexico for in situ testing and waste storage demonstration. If after the demonstration, the facility is found to comply with regulations of the Environmental Protection Agency, then the facility will become a repository for Transuranic (TRU) waste. The underground portion of the facility is 655 m beneath the ground surface in massive natural salt deposits of the Salado formation, as shown in Figure 1.

Jan 1, 1991

By M I. Pownceby, N A. S Webster, A J. Studer, I C. Madsen, J A. Kimpton, M J. Fisher-White, L Lu

In situ synchrotron X-ray and in situ neutron diffraction-based experimentation have been implemented to characterise the formation of the complex calcium ferrite iron ore sinter bonding phases silico-ferrite of calcium and aluminium (SFCA) and SFCA-I. Experiments were carried out using fine-grained (<20 ¦m) sinter mixtures containing ~77 wt per cent Fe2O3, 14 wt per cent CaO, 3.5 wt per cent SiO2 and 5 wt per cent Al2O3, with diffraction data collected during heating until 1300 - 1350¦C, which was enough to ensure complete melting of the SFCA phases. In the case of the in situ synchrotron experimentation, results showed that altering the nature of the starting sinter mixture (ie substitution of goethite for hematite; substitution of an amorphous Al2O3-based mineral for gibbsite) did not have a significant effect on the thermal stability range of the SFCA phases. It did, however, have a profound effect on the formation and rate of consumption of the calcium-rich ferrite phases C2F and CF, and on the formation mechanisms of SFCA and SFCA-I. The in situ neutron diffraction experimentation is the first described in the context of iron ore sintering, and the observation of both SFCA-I and SFCA formation in the in situ diffraction data represents the first step in achieving the goal of charactering iron ore sinter phase formation in large volumes of industrial sinter starting materials with a wide range of particle sizes (up to 6.3 mm).CITATION:Webster, N A S, Pownceby, M I, Madsen, I C, Studer, A J, Lu, L, Manuel, J R, Kimpton, J A and Fisher-White, M J, 2013. In situ x-ray and neutron diffraction studies of silico-ferrite of calcium and aluminium iron ore sinter phase formation, in Proceedings Iron Ore 2013 , pp 487-494 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Desiree Willis

At 6 percent downgrade to a low point beneath California?s Sacramento River, the Lower Northwest Interceptor Sewer was a difficult project from the outset. Project owner Sacramento County Regional Sanitation District (SRC-SD) planned to excavate the V-shaped tunnel in two sections using an earth pressure balance (EPB) machine in soft ground. Muck removal, due to the steep downgrade, was a tricky proposition. ?We did look at muck cars, but determined they were not the best option due to the relatively steep slope of the tunnel alignment. The safety benefits of conveyors on this job were obvious, as there were not the potential hazards associated with muck cars traveling on an incline or derailing,? said Steve Norris, senior civil engineer for SRCSD The successful project represented one of the first instances of a conveyor system being used for a soft ground tunnel boring machine (TBM) application. Several projects in California, including a recent tunnel completed in 2009, have highlighted a growing acceptance of conveyor muck removal in a variety of ground conditions. Conveyors offer higher system availability than more common methods, such as muck cars, as they allow for continual operation of the TBM. The design of conveyor systems must, however, take into account the differences in material between soft ground and hard rock, including belt cleaning features, sealed transfer points and other elements.

Jun 1, 2010

By A Kite

Frontline leaders play a critical role in the safe and productive operations of Australia’s mining, resources and heavy industries. These leaders set the workplace culture, especially during night shifts and weekends, by providing team direction and encouragement, providing access to resources, fulfilling statutory requirements, enacting and reinforcing risk management systems, setting the standards on shift and acting as the primary conduit of communications between senior leaders and team members.

May 5, 2022

By J. F. Allan

The main conditions which affect investment in mineral exploration and development are compared in five countries currently considered attractive for mineral investment - Canada, the U.S., Australia, Brazil and the Philippines. The primary parameters - the probability of occurrence and discovery of mineral deposits and the short and long term viability of mineral development - are evaluated and compared on a relative basis by a form of factor analysis. This analysis indicates that of the five countries studied, Canada is second only to the United States in degree of favourability for mineral exploration and development.

Jan 1, 1976

By Robert L. Bates

On April 2 and 3, 1970, more than 100 geologists attended the Sixth Annual Forum on Geology of Industrial Minerals at Ann Arbor, Mich. After this brief appearance, the Forum apparently ceased to exist- but it didn't really, and another spring will see it again in action, in another corner of the country. The organization might be characterized as the country's largest permanent floating conference on the geology of industrial minerals. What is the Forum, where did it come from, and what is it up to? The idea originated in 1964 with a small group in the Department of Geology at Ohio State University, Columbus. This group felt that a forum was needed for the exchange of geologic information on industrial rocks and minerals. They envisioned an approach-which has subsequently been adhered to--that would be dominated neither by geological academics interested in theoretical problems nor by practical engineers concerned with processing large tonnages of rock. It was proposed to focus attention on the middle part of the spectrum, especially on practical problems of geological occurrence and how these problems affect extraction and use. In terms of the standard rock-products flow sheet, which starts with a truck unloading into the primary crusher beneath the words 'from quarry,' it was proposed to focus geological attention on what is beyond the primary crusher, out in the quarry.

Jan 1, 1970

By Lawrence F. Rooney

One of Edgar Allan Poe's stories that haunts my subconscious is the Masque of the Red Death. These days, whenever I join a group like this, especially during the cocktail parties, I see myself and others as those mythical swingers seemingly isolated from the plague. The world, but this country especially, has had a ball plundering, spending, and wasting its natural resources for 100 years. And, as in days of yore, it is fitting that we end this ball with spectacular fireworks: trips to the moon, so that our grandchildren, huddled in their caves along the Ohio, will better understand how it all began.

Jan 1, 1970

By F. Heivilin

If the past is the key to the future, we will have ?tough? times maintaining Industrial Mineral reserves we have and proving new reserves around our plants and in new locations. The tough times will come from resources being more difficult to find, more hoops to go thru to make them Proven or Probable reserves. As always, Industrial Minerals require competitive quality, location, and costs. Since in most cases the market has suppliers, you will have to take away customers from their present supplier. This may take years or not happen even with lower cost higher quality raw materials. To determine the finished cost for a new deposit you need to design, determine capital costs, and operating costs for a new plant . Stripping, mining, hauling, processing, and transportation costs are part of the equation. After satisfying that your costs are in line you will need to do production tests to make sure the process works on the ore. You may want to complete permitting before purchasing the property. If you are new in the business you will have to prove you can deliver the right quality, the right quantity, on time consistently year after year at lower cost to take away a customer. Without being in the market this will be hard. The cut off grades to enter a market may be much lower than sale indicates because a competitor often lowers the price to keep you out of the market. We have many more items to check before the new deposits can be put on reserves. Our old reserves will require drilling to check for new products and prove that they do not contain items that would make them unusable for our product line or cause permitting problems. Archeological checks, wetlands, more water discharge testing, county zoning, and endangered species are among many items that have been added to mine permits. There will be more. A 4-6 page mining permit becomes 30-300 pages and consists of 5-15 permits, any of which might be a fatal stumbling block. It is not guaranteed that we can mine what we have on reserves. We may fight and lose. Oil-Dri?s loss in Reno and LaPort?s in England are examples where permitting failed. The NOx, sulfur, and carbon problems are just starting. Dioxin is in the background requiring monitoring on food products to Europe. What other anions, cations, endangered species, and land types are going to be problems in the future are guesses now. What new products are we going to have to test for and cause out of balance reserves? If there are none we probably won?t be here. We are competing for land use with ?Endangered Species?, wetlands, farming, forestry, cities, roads, and hunting. We?ve mined the best quality, low overburden, easiest to mine and process raw materials. The price of land and taxes are increasing. Old royalties are 2-3 times the present acre value instead of 8-10 times the property value when leased. Land taxes are up. It was and is best that we get the land in Fee Simple Title. This isn?t always possible. However, plants are closing and people have overlooked, made mistakes in drilling or interpretation of deposits. These may be opportunities. China is eating up high quality ?Industrial Minerals ?which have caused prices to rise. We may need to change our cutoffs? in terms of smaller pit sizes and higher overburden ratios. This is money in the bank. Overburden ratios and other items increasing cutoff costs need to be rethought. Suddenly doubling cutoff ratios for overburden and decreasing pit sizes are good alternatives to looking elsewhere where we might not be able to mine for a number of reasons. The higher prices make them competitive, especially when a competitor goes out of business. However, our low overburden ratios and short hauls around our plants are not safe from new roads, condemnation by county or city governments (N. J.), zoning changes (Reno, FL., CA, and environmental regulation changes (Buffers GA, MS). New roads ?Interstates? can take reserves, increase hauling distances and reduce tons per load. Let?s combine the Refractories, fullers earth, and bentonite industries and use the last 40 years as a guide to the future looking for problems and opportunities. Some or most of the following will apply to other minerals. WHERE DO WE LOOK? First, on our own properties, those next to our properties and on properties near our competitor?s plants. Where the profit margin has increased, the distance from the plant and thickness of overburden we can use is increased. The thickness of clay is decreased. For new locations we pick the ideal location and look at deposits and closed or open operations in ever increasing distances away from that location. We need to be aware of: 1. Increased transportation costs a. Access to Roads -Backhauls b. Haul with doubles and triples c. Railroads - Loading on sidings - Ability to get switches - Cars/backhauls versus rates 2. Cost of building a new plant 3. Cost of infrastructure 4. Cost of repair or new equipment when purchasing an operating or shutdown plant. 5. Local, state, and federal mine and environmental permitting. When exploring around an established operation expect that property acquisition, drilling, mining, stripping, and hauling costs will be greater due to them having second, third, or even fourth the pick of the deposits. I found this in New Jersey looking for refractories and around Quincy, Florida looking for attapulgite. You may be able to get some better properties because the operating company has angered some land owners, their drillers missed the clay, or the property wasn?t available when they were actively exploring for reserves. You may have some product lines your

Jan 1, 2009

By W. E. Wallace, V. Robinson, M. F. Keane, V. Vallyathan

"An in vitro study of the biologic responses of surface-modified and native silica and kaolin was made to provide comparative information on the supression of cytotoxicity by pulmonary surfactant. The release of alveolar macrophage cytoplasmic enzyme, lactate dehydrogenase (IDH), and lysosomal enzymes B-N-acetylglocosaminidase (B-NAG) and B-ghucuronidase (B-GLUC) and sheep blood-cell hemolysis were moni¬tored as indicators of cell membrane damage and cytutoxicity. Surface modification of silica and kaolin with dipalmitoyl lecithin (UPI) resulted in complete abrogation of cytotoxicity of both minerals. These findings indicate that surface modification of minerals with different adsorption properties by pulmonary surfactant generally lessens their prompt adverse effects.INTRODUCTIONAcute and chronic silicosis are well-characterized clinical and pathologic entities resulting from the inhalation of crystalline silica (Morgan and Seaton, 1984). Kaolin, a layered aluminosilicate clay frequently mined and used in manufacturing, contains tetrahedral silica alternately layered with alumina octahedra. Kaolin is relatively .inert biologically, and distinctly greater pulmonary burdens are seen in patients with kaolinosis than are seen in patients with silicosis. Crystalline siliea (quartz) induces a significantly greater degree of fibrosis in exposed animals in vivo than does kaolin (Hamilton and Hardy, 1974; Parkes, 1982; Hunter, 1976; Sheers, 1964; Warraki and t-lerant, 1963; Lynch and Mciver, 1954; Lapenas et al., 1984).This difference in pulmonary disease associated with the two types of dust is not reflected by in vitro cytotoxicity as Jetermined by pulmonary macrophage bioassays or erythrocyte hemolysis. Cytotoxicity studies using crystalline silica and kaolin of similar size fractions show comparable bioassay response on a mass basis. These cellular bioassays, therefore, do not correlate with the relative in vivo pathogenicity of silicates."

Jun 1, 1988

By R. J. Matetic, David S. Yantek, David K. Ingram

The National Institute for Occupational Safety and Health (NIOSH) has investigated engineering noise controls to reduce sound levels in cabs on air-rotary drill rigs. A recent investigation revealed that some drillers are exposed to A-weighted sound levels exceeding 85 dB even though a cab is used. NIOSH studied the in-cab sound levels of one such rig. First, preliminary tests were conducted in a controlled environment using accelerometers and microphones with spectral analysis to identify the dominant noise sources for in-cab sound levels. The results indicate that vibration transmitted from multiple hydraulic pumps to the control panel produces a dominant spike in the sound level spectrum in the 400 Hz 1/3-octave band. Next, field tests were performed in a production environment to evaluate noise controls to reduce in-cab sound levels. It was found that utilizing hydraulic noise suppressors reduces the structure-borne noise transmitted to the control panel. Further, using hydraulic noise suppressors and enhancing soundproofing reduced the in-cab A-weighted sound levels by as much as 4 dB.

By Edward Thimons, William A. Hertbrink

The effect of wind speed upon aerosol penetration into an idealized enclosure was studied The idealized enclosure was a painted plywood box that was 1 2X1 2 XI meters in volume Two fans supplied 1 7 m3 /min of filtered air to this enclosure at a static pressure of 2 8 mm of water The enclosure had a 7 5 cm diameter vent port which was isolated from the air flow around the enclosure To simulate holes in real enclosures, three 16-cm diameter holes were drilled on the front and back sides of the enclosure This simulated enclosure was placed in a tunnel-like structure The air flow from an ultra-light air craft was directed at the front of the enclosure The air speeds were varied between 14 and 36 km/hr as measured by rotating vane anemometer Static pressure in the enclosure was measured with an electronic manometer Two optical particle counters measured the particle number concentration of particles between the 0 35 to 0 5 µm inside and outside of the enclosure Aerosol penetration into the enclosure was computed as the ratio of the aerosol concentration inside the enclosure to the concentration outside of the enclosure The enclosure static pressures measured increase from 2 8 to 3 4 mm of water (P=00001) Aerosol penetration into the enclosure increased linearly with air velocity above 20 km/hr Theoretically estimated penetrations were correlated with observed penetration into the simulated enclosure When simple linear regression was used to model the observed penetration as a function of the estimated penetration, the value of the slope was 0 69±0 12 and the P value for the regression model was less than 0 0001 These results indicate that enclosure static pressure needs to be higher than the wind's velocity pressure in order to minimize aerosol penetration into these enclosures

Jan 1, 1999

By P. S. Mukherjee

Mineral ilmenite is a major resource for titanium, whose major application is for production of Titanium dioxide (TiO2) for pigment application. The production of pigment grade TiO2 from ilmenite was earlier carried out by acid leaching, which has now been banned due to environmental regulations. Further acid leaching leads to loss of iron metal values as sulphate or chloride which are also treated as effluent. In thermal plasma processing the metal values are recovered as high value pig iron and Titanium dioxide is recovered as Titania rich slag containing 80 to 85 percent TiO2. The Titania rich slag has now been considered as a better input material than synthetic rutile for production of pigment grade Titanium dioxide. On the other hand, high value pig iron goes for automobile industry for specific application. An Inflight-flight Thermal Plasma Processing plant, used for the production of Titania Rich slag and high value Pig iron from ilmenite, with 20kg capacity was designed and fabricated. The reactor has the provision to utilize the flue gas generated for preheating the input of raw materials. Various aspects of designing the furnace operation include viz. Feeding the raw material at a fixed rate, designing the crucible used for melting ilmenite, proper cooling arrangements, an innovative method for tapping the melt, recovery of heat from the gases, various safety arrangements which are some of the important milestone of the present work. The various operations have been carried out through a controller panel. Experiments were carried out to optimize various processing parameters using statistical modeling. Large scale experiments have been carried out at 10 to15 kg scale. The material balance has been calculate, and it has been observed, that about 95 percent recovery could be obtained for both Iron and Titanium oxide from ilmenite. The detailed characterization on Titania rich slag and iron has been carried out. It has also been shown that using the above slag, it is possible to prepare nanosized Titanium dioxide powder containing about 98 percent Titanium dioxide by optimizing leaching conditions. Keywords: titania rich slag, ilmenite, thermal plasma

Sep 1, 2012

By Kumar Ashish, Shukla Akhilesh, Kr. Rokkam Kiran, M. Sheeba, S. Sombhatla Sundar

"Purification of zinc leachate plays a predominate role in zinc leaching refineries, to produce impurity free cathode sheets. As a part of such purification sequences, copper cementation with zinc dust is the preliminary step, since the presence of copper will preferentially deposit during zinc electro deposition and has the effect of reducing current efficiency. The cake thus produced is being accumulated as an inventory, due to invariable market and leading to space constraints & hazardous ambience. Hence, a project has been taken up for in-house generation of copper sulphate solution through ammonical leach followed by solvent extraction process and utilizing it as an active promoter for zinc sulphide flotation in Hindustan Zinc’s own captive mines. Cold purification cake majorly contains copper (30-40%) along with zinc (10-20%) and cadmium (2%). Confirmation to the above statement, photomicrographs of purification cake also confirmed the major presence of copper in metallic or oxidized form. In present work ammoniacal carbonate leaching of purification cake followed by solvent extraction using diketone based solvent has been studied under the influence of various parameters viz., temperature, agitation, pulp density, ammonia, CO2 dosages, solvent concentration, and impact of w/s zinc on leaching and solvent extraction. Leaching kinetics determined based on shrinking core model. Chemical reaction at unreacted core was found to be the rate controlling step. The estimated activation energy was found to be 24 KJ/mol. Leached copper has been extracted by solvent extraction with a ß diketone based solvent and is stripped with sulfuric acid as concentrated copper sulfate solution. The above established R&D findings are successfully implemented in the Commercial plant with a treatment capacity of two tons of cold purification cake per batch. Till now 500 MT of Purification cake has been treated, and generated 6500 MT of copper sulphate (55 g/l Cu), with final Cu recoveries between 87-90%."

Jan 1, 2018

By Robert W. Roscoe

For over a century, St. Joe Minerals Corporation in Southeast Missouri has been sinking shafts for their lead mining operations. Upon discovery of the Viburnum Trend, or "New Lead Belt", St. Joe brought its experience and expertise in shaft sinking to the area. Eleven shafts were then sunk in an 18 year period, ending in 1972. In 1981, St. Joe began sinking a new shaft in the Trend with hand-picked employees from the four operating lead mines and service facilities. The paper describes the general history of St. Joe shaft sinking methods and equipment, focusing on the current development of the Viburnum No. 35 Shaft.

Jan 1, 1983

Reduce the costs associated with conventional treatment of acid mine water. Approach Conventional treatment of acid mine drainage consists of plants requiring large mixing and aeration tanks, mechanical aerators and large, shallow settling ponds. Such plants are usually very costly to construct, maintain and operate. The Bureau of Mines has developed a simple, low-maintenance, highly efficient system to treat acid mine drainage which mixes, aerates, and neutralizes mine water Simultaneously in the existing discharge pipeline by using the pressure generated by the deep mine discharge pumps. The mixing and aeration action of the in-line system significantly increases oxidation rates of ferrous iron. Iron and manganese are removed, even at near neutral pH levels, due to the high efficiency of this system. How It Works The In-line Aeration and Treatment System (ILS) consists of two commercially available components, a jet pump (ejector) and a static mixer. The jet pump is simply a nozzle that converts water, already under pressure, into a high-velocity stream that entrains air by Venturi action. If neutralization is required, sodium hydroxide or lime is added along with the air at the Venturi opening. The aerated and neutralized water then enters the static mixer, which is a length of internally spiralled pipe that mixes air and water together. The two components, which are both about 8 feet in length, replace the last section of discharge pipe at a point before the mine water is emptied into a pond. Along with the settling pond, these components treat the water so that it meets discharge criteria. The system has been used at surface drainage treatment facilities as well, but in such use a pump is required to provide the necessary pressure drop across the Venturi opening.

Jan 1, 1985