US2610901A

US2610901A - Pipeline transportation of solid materials

Info

Publication number: US2610901A
Application number: US8297A
Authority: US
Inventors: Jr Walter M Cross
Original assignee: KANSAS CITY TESTING LAB
Current assignee: KANSAS CITY TESTING LAB; KANSAS CITY TESTING LABORATORY
Priority date: 1948-02-13
Filing date: 1948-02-13
Publication date: 1952-09-16
Anticipated expiration: 1969-09-16

Description

specific illustration of one Patented Sept. 16 1952 UNITED PATEFN name TRANSPO TATION OF soLfiJ MATERIALS 'Walter -Gro s: s; !r,, Kansas City, ill/ 61, assig nor to Kansas City Testing Laboratory; --Kansas City, M03, a corporation of Missouri 1N0 Drawing. Application February 13, 1948,

Serial N0.;297. I9 claims. (01. 302mm This invention relates to methods "of transporting normally solid materials and, "in particular, refers to transportation bypip'eline. I p w p As is common knowledge, themost widely used transportation media for large quantities of solid materials are the railroad, thefship and the motor vehicle. In general, 'theseimediajurnish an efiicient and inexpensiveiiiethod of transportation. There are conditions, however, "to which such means of transportation are not well adapted and wherein theiruse becomes iii' fi cient and costly but of allproportion totlfe value of the material being shipped, dipairtie ar in} dustry in which suchconditions are often 'found is the mining industry. ,7

Many mines both old and new as ieic ateu 'isolatedregions which are mpqssibie reach by ship and which are considerable distances,

often including rough terrain, from established rail and truck lines. The shipping of material from these mines by conventional means implies a very large initial investment rolling stool: and a large regular outlay to maintain and operate the equipment, In addition to the transportation means itself, the investment stals'o provide for warehouses, stockpilesloading' equipment, etc., since, unless 'thereis an excess or equipment, the shipping can only be do'n'e intermittently Because these and many Dill Grills;- advantages of conventional transportation media greatly increase the cost of the mined products to the consumer, the niarktaliility of many products is low in rela to th actualfv'alue "rodu'c'ts are and in many cases valuable e simply abandoned at the .r'n'irle because transporf tation costs price thenioutof themes 2A" a the aterials the U H tea Stats, carries a mini "uni freight hardener seven and a half s uare a tori, (It gene for per ton.) Any reduction in the cost of trans porting potash would lower its priceand directly aid the farming and 'agricultural indus'try and indirectly aid everyone the country; Iii the mining of potash near c -aastaa nav Mexico, sodium chloride (common tablesalfl is spy product. Because of the high c'os'to'f transpor tation 10,000 tons of this material are abandoned daily since its ultimate consumer price won ,be too high. A decrease in the costof transpo ting sodium chloride would make it possible use a product now being abandoned and lower the cost of an essential food item. 5 I

most valuable fertilizer Because of these andma :5 other instances of excessive costs due to mi's'applie'a'tion of conventional transportation media, it has" been a' principal object of my inventive efforts to reduce the cost of transporting soiubieimatena s' and materials which are availablairi relatively small granules or particles. p

In order to reduce" transm ttance sgp'z gg materials of the types mentioned, 'I incorporate manta I f eder;

than. the

is considerably less and for example, are also considerably less. Figures transportation Icosts of about 7 If solid materials are to be successfully transported by pipeline, they must, of course, be put into a; fluid condition and. maintained in that condition until the point of delivery is reached. Solid materials may be put in a fluid condition by dissolving them ina suitablefiuidyniediuin or byjus fidine t em; in fluid medium having c it and d s p ve Set.- s a yi s'cou s' fiuid media i transporting I articles; the present invention q hte n iat s the use f e1s1 or suspen idnspf the colloidal clays; especial aqueous colloidal "suspgn n 1 preferred form bf the invention a1 t e of colloidal eiayjisusfedwnicn has .0 1h" masse recofvierg o'r memesup ted; materi-als threfrom'.inayfb'e' easily and she ply accomplished by suitable piste-sees such as ffil r'atio'n, I t'i'ofi and assessing;

In order-to descr be'n'iy invention mete sip cally, I shall new refer toseveral examp s there of which, it will be understood, are mer'iymtstrati've. I

Example-'1 According 'to 't his eir ample of the" invention a Wyoming type bentonite clay parts (by weight) 6 Water parts 100 Granular material (coal for example) parts When the clay and water in these proportions are violently agitated together, a gel is formed having a Stormer viscosity of about fifteen to twenty centipoises. The coal particles may be added to this gel and the mixture forced by suitable means, mechanical means or by gravity, through the pipeline to the desired point of delivery. The coal may be then separated from the mixture by suitable means, filtration for instance, and, if desired, washed and dried, after which it is ready for marketin or use.

Insoluble solids are most suitable for the bentonite base transporting medium since soluble materials, particularly the salts, have a tendency to flocculate the clay. This is true of the gels formed by all of the colloidal clay materials except that used in Example 2. This tendency to flocculation can be overcome to some degree, however, by careful dispersion of the clays in fresh water followed by addition of the soluble material which it is desired to transport. This material can, of course, be subsequently recovered by evaporation or similar methods.

Other colloidal materials such as the Texa type bentonite clay may be used in this process and obviously many other materials, iron ore, for instance, may be transported by means of the medium of this example.

Example 2 In this example a gel is used as both a dissolving and suspending medium for the transportation of a single soluble material or a plurality of soluble or soluble and insoluble materials. A typical mixture according to this example might be as follows:

Florida-Georgia type fullers earth parts (by weight) 6 Water parts 100 (1) Potassium chloride parts (in solution) (2) Potassium chloride parts (in crystals)-- 35 The Florida-Georgia type fullers earth should contain a substantial amount of its natural water of hydration. It is then capable of forming a gel in salt solutions. At 70 F, a saturated water solution of potassium chloride consists of thirtyfive parts of the salt and one hundred parts of water. Such a solution may be prepared and the six parts of fullers earth added thereto.

When these ingredients are thoroughly mixed by suitable means, such as the dispersion mill of Patent No. 2,044,757, a gel having a Stormer viscosity of about twenty centipoises is obtained. An additional quantity of potassium chloride crystals, preferably of sufllcient fineness to pass a 100 mesh screen, equal to the amount in solution (35 parts) may be added to this gel without appreciable settling. This mixture of dissolved and suspended potassium chloride and a gel may then be forced through a pipeline to the desired destination.

At destination the solid crystals of potassium chloride may be filtered out, centrifuged, or separated by other suitable means from the repipeline.

maining colloidal salt solution. This operation may be facilitated by the use of a thinning agent which may be sufficiently effective to reduce the viscosity to the point where the crystals will completely settle out. Surface tension modifying agents, such as the sulfonated alcohols, can also be added to facilitate separation of the granular material. The dissolved salt may be recovered from the solution by suitable methods of evaporation or precipitation.

The usefulness of the foregoing mixture may be increased still further by adding another material which can be dissolved in the solution of the potassium chloride. Such a material is sodium chloride and thirty partsof it may be dissolved in the saturated salt solution previously described. The dissolved sodium chloride and potassium chloride may be separated from each other and from the solvent; by suitable methods at the pipeline terminus.

The foregoing, mixture is of great practical value since sodium chloride is a by-product in the winning of potassium chloride from sylvinite deposits. Heretofore it has been abandoned because of high shipping costs. It is now possible to transport it at virtually no cost since it can be added with no liability to the transporting medium containing the mined potassium chloride.

It will be noted that the fullers earth'of the type above described is particularly valuable in regions where only mineral waters are available as solvents. This clay readily forms gels in these Waters so that, even though an undesirable dissolved constituent is also transported, a transporting medium formed therewith will have sufllcient viscosity to carry desired insoluble particles.

It will be clear that the specific ingredients, their proportions, and the viscosities of the transporting media may very widely and must be determined in each case by simple "experiments or by the judgment of one practicing the invention. If a normally solid material (or materials) is to be transported in the dissolved state the solubility at the lowest temperature encountered en route should be taken into consideration, since an excess may be'precipitated and settle in the Solubility can be easily determined from handbooks or simple tests. When a dissolved material is used, a trial analysis should be prepared on a test tube scale to make certain that it does not flocculate the colloidal gel. As indicated, it is. desirable to use Florida-Georgia type fullers earth having a substantial amount of its natural water of hydration when a dissolved material is transported because of its resistance to flocculation.

Certain properties of the suspended articles should also be taken into consideration before proceeding with full scale operations according to the transporting method of my invention. These should be considered in conjunction with the viscosity and density of the liquid transporting medium. It will be realized that both the density and viscosity of the liquid medium provide resistance to the settling of the suspended solid particles. In general the density of the liquid medium or gel is increased by the dissolved material to be transported, hence a gel having the desired amount of material in solution should be used in the making of tests and decisions. If the solid particles to be transported are less dense than this liquid medium, there is no problem of settling and the transporting medium need not be viscous. This occurs only inunusual cases, however, and it is generally necessary to provide omega viscous resistance to se' ling to supplement the or the conflicting considerations of suspending power and resistance to flow. I havelfoundithat the most desirable range of wi's'cos'i tyii'sffifteen to twenty centipoiss, as determined by the Stormer viscos'imeter, tho'ug'h :special considerations, especially pipe size, encountered i'in'iparticular cases often make it desirable to use cos'ities outside of thisrange.

The second factor which affects iviscous ares'lstanc'e'is the size and shape f the solid -particles. It is elementary that the "resistance to settling is directly dependent on' the suri'acearea of the particles. In general, little control can be exercised over the *shape of the individual :particle. When it can, the surface area :should be as large as "possible in relation to (the particle's 'weight'or specific gravity. lfotal surface *area .is increasedibzl decreasing the size of ithe :individual particles. While particle shape control ma :not be always possible, it usu'ally possible toifcon- "trol particle size to some extent by :mechanical or other means. This provides a convenient means for -controlling the viscous-rcsistancewhen a'specifiedviscosity is desired.

The desired particle size, :shape and area as well as the viscosity of the I-iqu'id medium may be determined i arbitrarily or, preferably, by simple tests. These tests consist merely in preparing a small sample of the viscous liquid medium, adding thereto some of *the solid particles, and observing the rate of settling of these particles. I prefer to have the rate of settling ran within the range of zero to one foot per :minutethough it will "be understood that a greater rate of settling maybe tolerated iii the pipeline is short or if there iisjsufficient agitation within the pipeline to inhibit settling. If such tests show too great a rate of settling, the viscosity of the liquid medium may. be' increased though, as indicated above, when the viscosit is about fifteen to twenty .centipoises it is more desirable to decrease the particle size -.or increase theindividual particle surface areas. If .such tests show a very low rate .of settling, it may be desirable to decrease the viscosity, by adding more solvent, and thus lower resistance to flow through the pipeline.

These tests can obviously also be used to determine the proportion of insoluble ingredients relative to the other constituents of the fluid transporting mixture.

In case it is not convenient "or possible to obtain a suitable rate of settling 'by controlling viscosity or particle surface area, agitation with- :in the pipeline may be'employed. I prefer to do this by riding the inside of the pipessomewhat similarly to the way in which gun barrels are rifled. When the fluid mixture passes through a rifled :pipe it is stirred so that the soli p ticles remain in suspension. Another means of agitation consists in placing a device in the pipeline, at intervals, which scrapes the sides of the pipe and picks up any settlin'gs. This type of '6 device used by pipeline companies to :clean their lines. I

When water is used as the solvent :and :dissolved materials are transported, ithere is :of :course, likely to be a problem of corrosion. I ihav'e found that by adjusting the =pH= of the fluid mixture to 'eo, i: possible, that HO GDF-IGSiOH occurs in steel pipe of good grade. I-n ca'se pH control is not satisfactory, the flpipes may, of course, @be mad'e of wrought onior lines with= gla'ss', rubben or other suitabl nraterials.'

ln view'oi the;foregoing it vsii'lrbe r'ealiz'edthat sneer Lm'ore soluble materials and one or more insolublelmatenalsmaybe-simultaneously transported by any method at 'aicost which :may, in

many cases, be 1 considerably less than that :or

other m'etho'ds. It has Zbeen shown and S1'1'Oli1d now be apparent that the ipr'ecise details or method may be rather extensiveiy modihed so (that the scope or my 'inventi'onshould "be deter- -mined' by theclaims. a

ample 2 would be insoluble so far as I the claims are concerned since (1 potassium zchloride "-fo-rmed asaturat'ed solution.-

1. The method-oi transporting granular materials i which: "comprises mixing solidmaterials with a liquid and a colloidal clay capable of forming a gel with the liquid, forcing the mixture through a pipeline, and recovering the material from the mixture.

I 2. The method "of transporting soluble materials which comprises mixing said materially-with a sol-verit therefor and a colloidal agen't capable of forming a gel with the solution'of material in solvent, forcing the mixture through a pipeline, and recovering the 'mater'ial'from the mixture.

3. .The method of simultaneously transporting a soluble material and "an insoluble granular-material which comprises mixing *said'materials'with a solvent for the soluble material and a cdlloidal -agent-capable.of forming a "gel with the solution of material and solvent, said :ge'l hav ing suffic'ient viscosity to suspend thegramilar material,

forcing the mixture through a pipeline, and re- I covering the materials from the mixture.

4. The method of transporting a granular insoluble material which comprises mixing said material with a liquid colloidal solution of a-colloidal clay having suflicient-vls'oosity to "suspend the material, forcing the mixture through a pipelair-1e, and recovering the material irom-tl-ie mixure.

'5. The method of transporting a granular insoluble material which comprisesmixing said material with a gel 'iformed by a-colloidal clay and solvent, said gel having su'fiie'ient viscosity to suspend the material so that it settles at a rate of substantially one foot per minute or less, forcing the mixture through a pipeline, *and reeovering the rn'aterialfrom 'the mixture.

6'. The" method oftransporting a granular insolublematerial whieh comprises mming 's'aid material with a gel formed by a colloidal clay and solvent, said gel having a viscosity of from fifteen to twenty centipoises, said material consisting of granules having surface areas such that their rate of settling is substantially one foot per minute or less, forcing the mixture through a pipeline, and recovering the material from the mixture, I

7. The method of transporting a granular material which comprises mixing granules of the material having, substantially predetermined surface areas with a gel having a substantially predetermined viscosity formed by a colloidal clay and solvent, said surface areas and viscosity being determined so that the granules have a substantially predetermined rate of settling through the gel, forcing the mixture of gel and granules through a pipeline, and recovering the granules from the mixture.

8. The method of simultaneously transporting a soluble material and a granular insoluble material which comprises mixing said materials with a solvent for the soluble material and a colloidal clay capable of forming a gel with the solution of material and solvent, said gel having a sufficient viscosity to suspend the insoluble material so that it settles at a rate of substantially one foot per minute or less, forcing the mixture through a pipeline, and recovering the materials from the mixture.

9. The method of simultaneously transporting .a soluble material and granules of insoluble material which comprises mixing said materials with a solvent for the soluble material and a colloidal clay capable of forming a =gel:with the solution of material and solvent, the viscosity of said gel and the surface areas of said granules being such that the rate of settling of the granules is substantially one foot per minute or less, forcing the mixture through a pipeline, and recovering materials from the mixture.-

10. The method of simultaneously transporting a soluble material and granules of insoluble material which comprises mixing said materials with a solvent for the soluble material and a colloidal clay capable of "forming-a gel with the solution of material and solvent, said gel having a viscosity of fifteen to twenty centipoises, said granules having surfaceareas such that their rate of settling in said gel is substantially one foot per minute orless, forcing the mixture through a-pipeline, and recovering the materials from the mixture.

11. The method of transporting granular insoluble material which comprises mixing said material with a viscous liquid colloidal solution of a colloidal clay, forcing the mixture through a pipeline, stirring the mixture while it is in the pipeline, and recovering the material from the mixture. V

12. The method of simultaneously transporting a water soluble material and an insoluble granular material which comprises mixing the materials with water and a colloidal clay capable of forming a gel with the solution of soluble material and water, said gel having sufilcient viscosity to suspend the granules, adjusting the pH of the mixture to substantially neutral, forcing the-mixture through a pipeline, and recovering the materials from the mixture.

13. The method of simultaneously transporting a water soluble material and an insoluble granular material which comprises mixing the .materials with water and a Florida-Georgia type fullers earth having a substantial amount of its natural water of hydration to form a gel of viscosity suificient to substantially support the insoluble material, forcing the mixture through a pipeline, and recovering the materials from the mixture. 7

14. The method of transporting a water soluble salt which comprises mixing a Florida-Georgia type of fullers earth containing a substantial amount of its natural water of hydration with a water solution of the salt to form a gel of predeterminedviscosity, forcing the mixture thus obtained through a pipeline, and recovering the salt from the mixture.

15. The method of transporting a water soluble salt which comprises mixing a Florida-Georgia type of fullers earth containing a substantial amount of its natural water of hydration with a saturated water solution of the salt to form a gel of predetermined viscosity, adding additional particles of the salt to the mixture thus formed of such surface area and amount as to cause only inappreciable settling, forcing the mixture through a pipeline, and recovering the salt from the mixture.

16. The method of transporting water soluble salts. which comprises mixing a Florida-Georgia type of fullers earth containing a substantial amount of its natural water of hydration with a water solution of the salts to form a gel of predetermined viscosity, said solution being saturated with respect to at least one of the salts, adding additional particles of the saturated salt to the mixture, said particles being of such surface area and in such amount as to cause settling at a rate of substantially one foot per minute or less, forcing the mixture through a pipeline, and recovering the salts from the mixture.

17. The method of claim 14 which includes the step of adjusting the pH of the mixture to sub stantially neutral.

18. The method of transporting particles of insoluble material by means of a liquid medium of a liquid and colloidal clay having a predetermined viscosity which comprises adjusting the particle size of the material so that its rate of settlin in the mediumis substantially one foot per minute or less, mixing the material and medium, forcing the mixture through a pipeline, and recovering the insoluble material.

.19. The method'of transporting particles of insoluble material of predetermined size by means of a liquid medium of a, liquid and colloidal clay which comprises adjusting the viscosity of the medium so that the particles have a. maximum rate of settling of one foot per minute, mixing the material and medium, forcing the mixture through a pipeline, and recovering the insoluble material.

WALTER M. CROSS, Jn.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,329,967 Greenstreet Feb. 3, 1920 1,431,225 Greenstreet Oct. 10, 1922 2,042,423 Krekeler May 26, 1936 2,128,913 Burk Sept. 6, 1938 2,359,325 McConnell Oct. 3, 1944 FOREIGN PATENTS Number Country Date 334,060 Germany Mar. 27, 1919

Claims

1. THE METHOD OF TRANSPORTING GRANULAR MATERIALS WHICH COMPRISES MIXING SAID MATERIALS WITH A LIQUID AND A COLLOIDAL CLAY CAPABLE OF FORMING A GEL WITH THE LIQUID, FORCING THE MIXTURE THROUGH A PIPELINE, AND RECOVERING THE MATERIAL FROM THE MIXTURE.