A Review of Hydraulic Pipeline Transport and its Future Development

A Review of Hydraulic Pipeline Transport and its Future Development

Co p vri g ht © IF .\C AlI to lllat io tl lo r Mine ral Resou rce D en'! opllH:1l 1 Quee tl sla tld ...\u st ralia. l'IW) A Review of Hydraulic Pipel...

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Co p vri g ht © IF .\C AlI to lllat io tl lo r Mine ral Resou rce D en'! opllH:1l 1 Quee tl sla tld ...\u st ralia. l'IW)

A Review of Hydraulic Pipeline Transport and its Future Development DR P.J. BAKER Bus iness Developme nt Departm e nt, BHRA Fluid Enginee ring , Cra nfie ld , Bedford, England

Abstract. There have bee n many developments in recent years in pipeline transport to enab l e them to be more wid ely used in industry . Substantial tonnages of materials t hat a r e not affected by water , such as coal and othe r minerals, aggr egates and wastes , can be moved o ver conside ra ble distances in quite small diameter pipes . Where there are no existing road o r rail facilities , long- distance pipelines are usually cheaper to instal l, and this advantage increases in difficult terrain . Pipeline ope r ato rs all over the world assert that hydl'aulic lines pay for themse l ves 1n a relatively short time, in spite of the hea vy capital outlay , and th is is equal l y true f or lin es convey ing slurries or pastes within a plant comp lex . This paper reviews some of the more important in vest igations in the hydraulic transpor t f ield . Although reference to systems ca rry ing a wide range of materials is made, the majority of re cent published data centres o n coal t ranspor t . The paper looks at the application to a wide range of particle sizes , the developme nt of non - aqueous slurrY1ng media and coal/water fuels . The review also looks at some of the equipment being proposed to provide more reliable operat i o n and in pa r ticula r the range of solids - handling pumps now available . The paper goes on to ide ntify areas where further research and developmen t is required and some of the many organisations undertaking this work . Finally the short , medium to long term po t ential for their use is discussed toget her with po lit ic al and other f acto rs like ly to 1n fl uence market growth . Keywords. Hydraulic t ranspor t ; slurry flow; min eral handling ; pipelines ; solids handling pumps . waste and othe r materials in slurry form. (Baker , 1979) . Some of the more obvious advantages o f p1pelines are t hat they are compact and have a hig h car ry ing capacity . They can be constructed in terrai n not always possible to othe r forms o f t r ansport . They are also en v i r onmentally more acceptable , in that t he pipelines can be buried without the unpleasant consequences of some surface transport systems. The main disadvantages of hydraulic pipelines are that applications are limited to materials tha t can be mixed with t he carrying med ium witho u t affecting the products final use . They are also limited to areas whe r e the carrying me dium is economically available , and f o r some mix tures there is concern about pipe line block age . Over any distance the pipeline is a fixed connection between two pOints . The relatively hiSh capital cost tends to limit t hem therefore to appl ic ations with high throughputs operating for several years .

INTRODUCTION The early history of pipelining of slur r ies is someYlhat obscure . There is some e vidence that the Romans used to t r anspo r t ore and tailings i n a slurry form . In recent times , papers have repo r ted on pipelines being used in the USA to pump sand from goldmines in 185CJ and waste o ut of coal mines in 1884 . In this century , the earliest documented system of significa n t size was ope ra ted in 19 13 , conveying coal through a 200 mm. diameter 540 metre long pipeline from barges in the River Thames in London to Hammersmith Power Station . It is claimed that the system ope ra ted satisfactorily f or some eleve n years befo r e it was abandoned due to blockage . Serious rese a rch in to slurry technology began in t he early 1950 ' s . The f i r st methodical experi mental study on fine - particle sl~ rries leading to empirical correlation was publ i shed by Dura nd and Condoli os in France in 1952 . It is interesting to note that , in spite of the tremendous amount of resear ch that has been undertake n s in ce those days , some of Durand ' s equations are still being used satisfactorily in design studies for some slurry mixtures. In the UK, wor k was ma1nly carried out by BHRA in conjunction with the NeB on coarse particle coal slu r ries .

A re cent reV Iew undertaken by the BHRA showed that over 50 mill ion tons of solids are pumped each yea r . If all t he plann ed pipelines go into operation , the quantity t rans po rted could rise to some 300 million tons per year. These figures do not take into account the in - plant applications , which tend not to be published . The majority of the proposed l ong distance pipelines are for coal transport in the USA (Baker , 1983) . The coal would be finely crushed to produce a pseudo homogeneous mi x tu re with wate r . Econ omic viability of these systems have been demonstrated by many designe r s . However , one of the ma jo r

In recent years the e mphasis has increasingly been on the development of slurry pipelines f or coal transport . However , the re a r e many hundreds of applicati ons worldw ide where pipelines are being used to pump a wide range of minerals , mineral I S9

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cost elements in fine particle slurry systems arises through the need to dewater the fine coal (less than 2 mm) down to about 20% prio r to use direct ly in power plants . For loading onto ships for export , the acceptable water content could be as low as 10% . Much work has there f ore been going on in recent years on improving dewatering techniques and to look at the possibility of operati ng at higher solid to liqu id concentrations and with l arger parti cle sizes . This wo uld have the add itional advantage of reducing crushing costs . This paper attempts to briefly review some of the recent developments, which cou ld not only widen the range of applications f or hydraulic pipelines, but also could redu ce some of the ope rating and ca pital costs . SLURRY OPERATING REGIMES The flow regimes for slurry transport are considerably more complex than those f or singl e phase fluids, and slurries may be both settling or no n- se ttling. Figure 1 identifies three main forms of mixture available to the user . Factors that will determine the regime in which the mixture is ope r ating are flow velocity , particle size distribution, density and concentration. FINE PARTICLE SLURRY SYSTEMS The technology of fine particle slurries up to 1 to 2 mm. size is well established for a whole range of materials and the majority of working systems operate in this mode . In general , a lmost any finely ground mi neral lends itself to long dis tance sl urry pipelines. Table 1 shows a selection of some of the major pipeli nes built worldwide. Table 2 identifies some of the more recent fine coal pipelines proposed. It will be seen that the majority of these are f o r very long haul application in the USA . In addition to the USA, two other countries have been actively apply ing this technology to industry. These are Japan and South Africa . A brie f rev i ew of the Japanese applications show that some 37 working projects - transporting sI i mes , raw coal or concentl'a tes, backfilling of mines and volcanic ash - were in ope rati on i n 1976 . The longest line is claimed to be 68 kilometers, pumping mine tailings . New schemes are being designed , parti cu larly f or land reclamati on . There are also many short pipelines in South Africa , specifically f o r handling gold slimes and tailings . These are usually less than 20 kilometers long but have been o perating successfully f or many years . With r ecent i mproveme n ts in process ing costs, further pipelines are being designed and built to transport the tailings back to mine plants to extract further gold. COARSE PARTIC LE SLURRY SYSTEMS The technology f or coa rs e parti cle slur r ies , having particles greater than 2 mm. and usually less than 100 mm., is now becoming available. It is in this area that most research and development is being undertaken at the present time , particularly in the USA , Japan , Canada , Germany , Aust ralia and the UK. In general, the application areas f or large particle heterogeneous slurry mixtures is for short distance applications of a f ew kilometers . There are a number of important advantages in pumping coarse- particle sized material, such as reduced preparati on and dewatering costs . Unfortunate l y , these mixtures require high operating

velocities t o maintain movement of the particles , which leads to both higher abrasion of the pipeline system and high specific power requirements. A limited number of coa rse slurry lines have been built , and it wou ld appear that widest experience of this type of regime exists in the Soviet Union, although there are reference s to papers of appli cat i ons in the UK by the Nati ona l Coal Board and in the USA. Re ce ntly the NCB built a 1 . 2 kil ometer coarse particle colliery waste slurry pipeline system f or a throughput of 200 tons per hour solids , passing a 38 mm . screen . In the USA , an initial design study was undertaken in 1982 to transport coal approximately 12 kilometers across Staten Island to a port from a railway terminal for expo rt pur poses . It is understood that this project has now been abandoned because of the r ecent change in market conditions . Future application areas are seen f o r vertical hOisting of minerals from mines and the sea bed and for waste disposal schemes. COARSE/FINE SLURRY SYSTEMS The limitations of pumping coarse particles in pipelines , referred to above , have led to the need for research into techniques that would allow i ndustry to move coarse materials over the long distances achieved by fine slurry systems . The possibility that coarse material could be pumped at low veloc ities with relatively low pressure gradients was first investigated by Elliott and Gliddon (1970 ) . They f ound that a heterogeneous slurry containing 13 mm. coal could be pumped, with the addition o f 25% fines to give a total concentration of about 60% , at low velocities and at relatively low pressure gradients . Further in depth investigations into these mixtures are being undertaken , both in the UK at BHRA and in Australia at CSIRO . Technical data available to the designer is still l i mited at the present time , however this form of regime ap pears to have wide applications and can be considered for both short a nd long distance systems . Recent work in Australia (Duckwo r th , Pullum and Lockyear , 1983) , describes a series of tests ca rried out with mixtures of coarse and f ine coal slurry with concentrations up to 67% . The top size of coal was some 20 mm. The researchers have examined the sta r t up condition of the pipeline containing 67% concent rat ion afte r four day shut down peri od . Although the pressure requ ired was initially l arger than the co rre sponding steady state condition , the pressure gradient dropped to the value within a very rela tively short period of 30 minutes . Pi peline bloc kage did not occur . In addition to coal , the BHRA have recently been applying this technology to the disposal of mine waste. Here the requirement i s for the disposal of very large quantities of wide particle range material with the minimum of handling , and if possible , avoiding dewatering altogether. The future potential f or applications us in g this f orm of mixture looks promising , particularly within the coal industry. At present , the only kn own simi l ar mixtures pumped at high concentration and wide particle size range are conc r ete and mine pump- packing systems . Both these app li cations a r e over short distances with relatively high f r iction losses . NON - AQUEOUS CARRIER FLUIDS Much effort has been put into overcoming the problem of dewatering material, an area of major concern to users . In addition to improving the pe rf ormance of dewatering plants , a number of non -

A Rev iew of H ydraulic Pipeline Transpo rt aqueous media have been investigated . Again , the main application has been for transporting coal . The principal candidate media were identified as crude oil , fuel oil , methanol, ethanol , and carbon dioxide. COAL/OIL MIXTUR ES These are based on heavy fuel oils loaded to a weight concentration of 40 to 50% pulve r ised coal , about the same as crude oil or water based s l ur r y . They are designed for direct f i ring into boi l e r s , hence require no separation . Another end use proposed is f o r direct injection into a blast furnace . The rheology of COM is not yet fully established , depend i ng on coal type , oil type, additives , temperature , particle size distribution and storage his tory . It would appear at the present time , for economic reasons , coal/ oil research and dev elo pme nt has been reduced. COAL/METHANOL MIXTURES Li ke c rude oil , methanol ow;es its at trac t i veness as a slu rry vehic l e to its value as pay l oad . In this capacity it has bee n re commended as a sub stitu te transpo r t media for natural gas f r om Alaska , the gas being converted to methanol at source . Methanol coal slurries ca n be pr epared and pumped in a similar ma nner to coal water slurries , but require a finer grind of coal if head losses and transitional losses are to be kept down . The research activity in this area is also small compared with conventional coal / water systems .

COAL/CARBON DIOX I DE MI XTUR ES In contrast to COM and methanol , carbon dioxide owes it attractiveness as a slurry vehicle to its ease of separation from coa l. This technology , whi c h is still in its infancy, is being deve l oped in the USA . A number of prospective advantages are claimed . It can be r eco ve red from coal without consuming water , liquid ca rbon dioxide is at least 1/15t h as viscous as water , allowing it to be loaded to a higher coa l conce ntration (i e 80%) and ve ry little C02 is absorbed by the coal , making it easy to separate and avoiding agglomeration or swelling problems associated with water. Carbon dioxide in large quantities could become a market able product for such end uses as enhanced oil r ecovery . Separation can be achieved by simple evapo ration of the carrier f l uid yie l ding dried ground coal a nd purified C02 . The researchers clai m that this process can be very economic compared with other pipeline techniques , but much mo r e work is required to con firm the technical long- term reliabili ty and safety of such schemes . COAL/WATER FUELS The rise in oil prices in 19 73/74 provided the incenti ve for research into methods to reduce e nergy costs . In addition to COM , CWF were investigated for dire ct firing in boi lers . These fuels are known by a number of proprietary names and differ mainly in particle size distribution and the viscosity reduc i ng and suspension stabil ising additives employed . I n general the maximum particle size is less than 300~m. with 75% to 80% less than 74~m. Conce ntrat i on by weight of coal is usual l y a bout 60 - 70% . De velopment work has been ca rri ed out in USA , Germany , Sweden , Holland , Japan and Italy , with the common objective of achieving a highly loaded

16 1

mixture wit h acceptable viscosity and stability . Many f ull scale tr i als have been co nducted , particularly t o determine combustion pe rformance. However , l imite d data seems to have been obtained and published to date on the pipeline performance of these mixtures , an d t his is an a rea whe r e info rmation wi l l need to be obtained before complete systems can be designed . It is claimed that the advantage of CWF over COM is its re du ced cost pe r unit of hea t. The cost advantage is c l aimed to be a pp r oximately 12% at present . However , becaus e of r ecen t deve l opmen ts i n the ma r ke tplac e , ie l owe r oil prices a nd r educe d ene r gy cons ump t i on , t he applicatio n of th i s technology is be ing limited , as boi le r conv e r sions a r e not being s o a cti vely carried out . EQUIPMENT DESIGN In paral l el with de velopments in fluid technology , A improveme n ts in equipment design has continued. review of papers presented at various slurry transport confe r ences would suggest that most elements of a slurr y system have received attention , with the emph as is on improving performance and widening the ran ge of solids handling pumps and feede r s availa ble t o t he designer , particularly fo r some of the coarse/fine particle slurry mixtures pr oposed. The wear characteristics of the many new pipel i ne materials available to the deSigner , now i n the marketp l ace , have also received attent i on . The cho i ce of sol ids hand l ing pump i ng equipment will depend on the various properties o f the slurry to be pumped , as we l l as satisfyi ng the norma l duty and installation requirements . The initial choice l ies betwe en some type of pump that handles the slurry di rect l y , with the attendant problems of abrasi ve wear and slur r y damage , and a f eede r system using a r emote source of clean driving fluid , wh i ch may be more complex and hence costly . All have some i nhe r ent l imitation on thei r performance or application . The two main groups of pumps are dynamiC and positive displacement (Fig . 2) . Dynamic pumps tend to be cheaper in both ca pital and maintenance costs and can handle relatively large solids; they are normally conside r ed for the higher flow , low pressure and less viscous applications . The co nverse applies generally to positive displacement types ; they a r e a l so more efficient f o r a given output and their pe r formance is largely unaffected by the pr ese nce of solids . The conventional roto dynamiC pump i s us ed f or most in - house app l ications , handling a wi de range of particle size s l urries over relative l y short distances . The number of pum ps available to the designer for handling coarse- particle slu r ries in longer distance applica t ions , where high pressures are required, is much more limited . Most positive displacement pumps have restricted fl ow areas at the inlet and outlet ports , which allow on ly the passage of fine and relatively fi ne particles . Some of the modern l ock- hopper systems have a very high capital cost and possibly high operating costs because of the many moving parts that could be subjected t o wear . Concrete pumps , which are readi l y available i n the ma r ket , appear to of fer the most pr omising solution at the present time to handle high conce n tration coarse/fine particle slurry mixtures. Most types are capable of delivering pressures >50 bar and have the additio nal advantage over the reciprocati ng pumps of the ability to handle mode rately large solids , due to the ' fu l l - way ' valv e design , as well as very viscous mixtures . The main disadvantage is the relatively lower output/unit , usually of the order of 50 - 100 m3/hr . Hence , several uni ts in

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parallel would usually be required, compared with more conventional reciprocating pumps . Development work is being undertaken to improve reliabi lity and phasing the stroking sequence between units in multi stage applications to avoid large pressure fluctuations when discharging into a pipeline . Fluctuation could have a detrimental effect on the slurry and the pipeline components. In recent years the manufacturers of these units have been aggressively marketing them for applic ations outside the concrete pumping field . An alternative design, which is now undergoing development trials, is the high- head rotary pump. This was invented in Australia for use with high concentration coarse/fine slurry mixtures for long distance applications (Boyle B. E. and L. A, 1979) . Manufacturers of roto- dynamic pumps are actively pursuing research into designs with improving operating efficiencies , longer life and easier maintenance . In addition , in order to extend their market into the long distance applications , work is being undertaken to produce units that operate at higher pressures. Extensive research has been undertaken into wear performance of pumps and pipelines because of the many factors that influence their working life. Rubber lining has been successfully used, giving lower wear rate than metals in both pumps and pipeline applications , providing the solids are not long or sharp . Polyurethane can give very good results as a pipe lining but its use in pumps has given somewhat conflicting information . The softer grades of both natural rubber and polyurethane appear generally more resistant than the harder ones . Ceramics are very wear- resistant but can be expensive and are susceptible to brittleness and thermal shock . New developments using ceramics in small pump applications may show improvements . Generally there is a lack of reliable quantitative data on the many factors affecting wear from which wear rates on new systems might be predicted with a reasonable certainty . Because of this the designer still has to resort to carrying out wear tests before he can finalise his design and operating cost figures. In addition to the general advances being made in conventional dewatering of solids, a major investigation has been underway in Australia for the treatment of fine coal/water slurries (Rigby and others , 1982) . The technique involves mixing the slurry with oil , which results in the small coal particles agglomerating with the oil . Spheres up to 3 - 4 mm. diameter are produced, which can easily be separated from the water by static screens . In addition , the clays washed out of the coal do not agglomerate . This integrated approach to improve the dewatering process in a slurry system and at the same time improving the quality of the product for the user could have wide application . Its economic viability depends primarily on the effective recovery of the oil at the end of the process where the user would not be prepared to accept the agglomerates containing oil for either technical or economic reasons .

Baker have been identified as having invested signifi cant funds to this technology include USA , Japan, Germany and Canada . Many other countries have been active to a lesser degree . Throughout this paper the author has attempted to identify some of the main areas where research and development has been undertaken. As to the future, advances will continue to be made, possibly at a lower rate until market conditions improve, into mathematical modelling of the various slurry flow regimes; equipment with greater reliability and laboratory and pilot scale pipeline tests on , in particular , the coarse/fine slurry mixtures. With limited resources available, there will be an increasing tendency for R & D to be aimed at specific application areas. To determine these areas , it is essential to look at the market opportunities for pipelines in the future. One potential growth area , particularly for Australia , is the application to moving coal and other minerals to the coast for export. The application of pipelines to the loading and unloading of ships, either in ports or off- shore from single- point mooring buoys, appears to offer many advantages both economically and environmentally. However , more demonstration work is required to establish the viability of the various schemes being suggested , the main requirement being to reduce the dewatering problem on board ships being loaded with coal slurries. Ship stability and unloading techniques need further investigation. The advent of the computer for system monitoring and control should lead to more efficient operations. Unfortunately , the availability of a full range of suitable instruments for accurately sensoring the main slurry parameters is also very limited, despite significant efforts to date. More work is required in this direction . In the longer term, economics will force the designer to opt for more fully automated systems if he is to compete with other transport systems and deliver an acceptable product to the user . Finally, there is an increasing need to ensure designers are kept abreast of developments through training courses and other forms of informative dissemination. There is no shortage of centres of technical excellence undertaking Research and Development studies available to designer and contractors. A worldwide review of published establishments identified some 49 in total , including 17 Universities , 8 Government laboratories and 20 industrial organisations . This total does not include many of the installations used by industry for in - house testing and are not therefore generally advertised or documented . Most pipeline test facilities are relatively short closed circuit loops having pipe diameters up to approx. 200 mm . The largest facility has recently been built in the USA and consists of 3 major loops up to 0 . 43m. dia . and 220 m. long. In addition, there are a number of specialist facilities , which are designed to look at both preparation and dewater ing techniques. CONCLUSIONS

FUTURE RESEARCH AND DEVELOPMENTS Since the mid 1970 ' s , there has been a rapid increase in research and development , particularly for applications of pipelines to the coal industry. The main emphasis has been increasingly towards establishing the technical and economic limitations of pumping coarse coal over relatively long distances. As a result of the recent down turn in the coal business , however , the level of R & D funding is now being cut back . Countries which

The future growth, both in the short and long term , for hydraulic slurry systems will be affected by a number of factors in addition to its technical development . Interest in hydraulic transport systems has ebbed and flowed with changes in economic and political situations . We are now seeing a further down turn in activities due to the present recession in the coal industry . Discussions with organisations actively involved

A Review of H ydraulic Pipeline Transport in R & D \vould suggest the re is tremendous potential . This is a natural r eac tion as most are fully co m mitted and enthusiastic about their own research . In practice there are few significant pipelines under construction or recently commissioned. It should however be stressed that most of these pipelines tend to be the major long- haul applications of typically between 10 and several hundreds of kilo meters in length . It is understandable that the greatest interest is shown in these major schemes because of the large contract value to those who are involved . However , it must also be noted that, throughout the world , there continue to be many small insignificant pipelines being designed , built and success fully ope rated, part icula rly f or the mining industry . As already mentioned in this paper, most 01 the major long- haul fine - coal pipelines planned for construction were in the United States . Major political pres sures have been brought to bear to stop these pipelines , particularly from the rail way operato rs. In addition to obtaining Eminent Domain , there is strong opposition from farm ers who are concerned with loss of their water. These factors, together with the recent industrial recession , will severely limit the number of long haul slurry pipelines to be constructed during the next five years . The number of coarse particle slurry systems to be constructed is als o expected to be very small, and limited to those of a few kilometers in length , again partly due to the present weakness in the market but also due to limited technical data and experience available . In the medium term , with growing pressures on land requirements , environmental issues , and rational isation of various industries , a greater trend towards the application of both short and long distance pipelines for handling a who l e range of minerals and mineral waste is expected . Also , un less more efficiently ope rated railways are avail able to industry , the operating cost differentia l will widen , wh ich will again increase the incentive towards pipelines. Although emphasis has been placed on the market potential for coal handling , applicat ions for the transport of many other minerals and waste prod ucts will increase. It must however be borne in mind that alternate pipeline modes of transport , including pneumatic handling systems , will inevitably offer increasing competition in some areas of application , particularly where water availability is limited . In predicting the long term potential for major slurry pipeli ne systems , both political issues such as Government's plans for railways in each country , transport infra- structure , and the rate of industrial growth will have a major influence in t he final analysis . Even without these factors, solids handling pipelines would not be expecte d to be as widely used as gas and oil pipelines . However, the fu ture f or slurry pipelines will be to play an increasing role in the operation of many industries .

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REFERENCES Baker , P. J ., and B. E. A. Jacobs (1979) . A guide to slurry pipeline systems . BHRA Publication, Cranfield , England. Baker, P. J . (1983) . Hydraulic transport by pipelines . Published Inst . of Civil Engineers, London . Boyle, B. E., and L. A. Boyle (1979) . The poten tial fo r hydrauli c transportation of coal in NSW colliery department. Quarry Mine & Pit Vol. 18 . No . 8 pp 10- 17 . Duckworth , R. A. , L. Pullum and C. F. Lockyear (1983) . The hydraulic transport of coarse coal at high concentration . ~. of Pipelines Vol. 3 . No . 4 Elseview Science Publication, Amsterdam . pp. 251 - 277. Elliott, D. E. , and B. J . Gliddon (1970) . Hydraulic transport of coal at high concen trates . Proc, 1st . Int . Conf . on Slurry Transportation , Hydrotransport, Warwick , U. K. Sept 1 - 4 1970. BHRA paper G.2 . Rigby, G. E., C. U. Jones ., D. E. Mainwaring and A. D. Thomas ( 1982) . Slurry pipeline studies on the BHP~BPA 30 tonne per . hr . demonstration plant . Int. proc . 8th Int. Conf . on Slurry Transport , HydrotransporL , Johannesburg , South Africa Aug 25 - 27 1982 BHRA paper D1.

REGIME

NORMAL FLOW CONDITIONS

Fine Homogeneous Particle Pseudo Systems Homogeneous Flow

NOMINAL PARTICLE SIZE RANGE AND CONCENTRATI ON BY WEIGHT - 2mm/50% - 300eunI70%

APPLICATIONS

Long haul syst . eg mine to power stations . Ship unloading . Full dewatering plant required. Coal/water fuel~ in - plan t.

Coarse Heterogeneous No top size Particle or limit but Systems Moving Bed usually up 50 mm with low proportion of - 100 eun . 3540%

Short haul syst . eg in - mine Vertical hoist ing . Ship loa ding/un loading. Reduced de watering stage .

Coarse/ Laminar Fine flow . Dense Systems phase or stab ili sed flow .

Both short & long haul systems . Ship loading/unload ing , in - port! offshore . Reduced de watering stage .

Fig .

1.

Usually up to 50 mm. with sufficient fines present to support coarse fract ions 60- 80% .

Di fferent Flow Regimes with particular reference to Coal Slurries

164

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TABLE 1

J.

Baker

Major Systems Constructed

Slurry Mater i als

Sys tern or Location

Coal

Ohio , USA Black Mesa , USA Poland U.S . S.R

Limestone

Length km

Diamete r mm

174 439 200 61

254 457 256 304

Rugby , U. K.

91

254

1. 7

Copper Concentrate West Iran KBI , Turkey

112 61

114 127

0.3 1. 0

Tasmania , Australia 85 Pen a Colo rado, Mexico 48 Samarco , Brazil 390 Chongin , North Korea 61 Kudremukh , India 67

229 203 508 N/A 457

2.3 1.8 12 4.5 7.5

Gilsonite

Utah , USA

115

250

1.3

Mill Tailings

Japan

68

305

0.6

Kaolin

Sandersville

110

450

0 . 07

Magnetite Concentrate

TABLE 2

Annual thruput (mt/a) 1.3 4.8 N/A 1.8

Proposed Coal Sl urry Pipelines

Location/Ope r ator

Length (km)

Diamete r (m)

Th r oughput ( t/aJ

Coalstream , USA

2400

0 . 35 t o 1.2

ETSI , USA

2240

0 . 4 to 1.0

Pacific Bulk , USA

1040

0 . 66

6 55 x 10 6 30 x 10 10 x 10 6

San Marco , USA

1440

0 . 51 to 0 . 61

10 x 10 6

Powder River , USA Alton , USA

262

+

30

0 . 56

6 9 x 10

109

+

8

0.3

Al ton , USA

*

& &

0 . 51

0 . 23

Snake River , USA

1760

0 .4 to 0 . 76

Texas Eastern, USA

2080

0.51 to 0 . 97

12.8

0 . 76

New York , USA

*

Virginia , USA

640 - 744

Poland to Austria

608

Poland to I taly

770

Italy to Austria

500

Jharia , India Singraulic , India

*

1759 1600

0 .4 6 0 . 46 0.25 to 0 . 525 0 . 3 to 0.525

6 2 . 5 x 10 6 16 x 10 6 25 x 10 3 8 x 10 hr - 1 6 6 5 x 10 to 25 x 19 6 5 x 10 6 6 5 x 10 to 10 x 10 6 5 . 75 x 10 6 22 x 10 13 x 10 6

Indefinitely deferred. Feasibility study only

I

Positive Di sp l acement Reciprocating

Dynamic

Rotary

Fig.

2

Pump Classification

I

I Centrifugal I

Peristaltic 1

-t Axial

Gear

J

-t

Screw

1

Vane

I I

Lobe

I

~

I

H

Vortex

I

Lt

Jet

I

Flow

Mixed Flow

-t Radial

Peripheral

Flow

Special High Speed (High Head . Low Flow)