US1349714A - Method of treating peat - Google Patents

Description

W. W. BLAJR.

METHOD OF TREATING FEAT. APPLICATION man nec.14,1s1a. RENEWED MAY 13,1919.

Patented Aug. 17, 1920.

2 SHEETSSHEET I.

Invenior. Wesley W. Blair ATT S W. W. BLAIR.

METHOD OF TREATING PEAT. APPLPCATION FILED DEC. 14. 1916. RENEWED MAY 13,1919.

1 34 9 ,7 1 4, Patented Aug. 17, 1920.

2 SHEETSSHEET 2.

InvenTor.

Wesley W. Blair byfimc adaf UNlTED STATES PEENT OFFICE.

WESLEY W. BLAIR, OF NE'WTONVILLE, MASSACHUSETTS.

METHOD or trnna'rrne mini.

Specification of Letters Patent.

Application filed December 14, 1916, serial No. 137,027. Renewed May 13, 1919. Serial No. 296,912,

To all whom it may concern:

Be it known that I, VVnsLnr BLAIR, a citizen of the United States, and resident ojlf Newtonville, county oi Middleseiz, State o'l Massachusetts, have invented an Improvement in Methods of. Treating Peat, of which the following description, in connection with the accompanying drawing, 1s a specification, like characters on the drawing representing like parts.

This invention relates to a process for the treating oi? peat for fuel purposes.

Freshl I dug or wet peat has a relatively small heating value due to its high percentage oi water contentabout 85 to 90 per cent. This content may be reduced below '70 per cent. by pressure or to atmospheric moisture by air-drying. Peat which is simply cut and dried is in a loosely aggregated mass and disintegrates dur ng handling and combustion and its calorlfic value is low.

At present, there are two general processes of treating peat to increase its availability as a fuel. One results in the production of machine peat and the other in co1npress d briquets. Machine peat, as the name is commonly understood is made by grinding and macerating the peat with about the same amount oi? moisture that it contains in the bog and thereafter cutting it into bricks as it issues from the outlet of the grinding machine in a thoroughly macerated condition but suificiently stilt to retain its form. Machine peat is only very slightly compressed yet its thermal efficiency is higher than that of the cut peat and its more firm state permits of greater facility of handling, transportation and storage. Compacting peat increases its etliciency and lasting qualities as a fuel and makes it more easily transportable and storablehence, the more expensive briqueting process. Briquet peat is made by dry ing the peat as taken from the hog nntll the water content is reduced to about 40 per cent. The peat is then powdered and dried artificially to above 15 per cent, moisture, It is then formed into blocks by enormous pr .SSll'l'fi in a briqueting machine or press. The cost of production oi briquet peat is at least one-third greater than that of machine peat, whereas, the heating value is increased only about 15 per cent. The advantage oi hriqueting is that the number or heat units is increased per unit oi? volume. It can therefore be transported and stored in smaller spaces and burned in smaller fireboxes. Furthermore, briquets burn less rapidly than machine peat and, hence, give less trouble in firing for power purposes. However, peat in briquet form, even more than the machine form, is friable, liable to crack and crumble when handled and to break down in the combustion chamber into a powder and thus blanket the fire.

It is this liability and tendency to dis integration of the present peat forms which is overcome in this novel invention coinci dently with the increase in the calorific value of the peat.

In this improved process, the fuel value of the prepared peat is raised by the treating of the peat with a low grade oil. The steps preliminary to the oil-treating are such that the peat is so presented that it may readily absorb the oil and yet preserve its hard, firm structure.

This is broadly achieved by blocking the freshly dug peatin its wet state. The peat is not macerated or ground and hence the fibrous, cellular structure is not so completely broken down as in the case of machine peat; nor, is it first dried and powdered as is the friable briqueted poet. The next step is air drying in open racks. The resultant blocks are hard, lirm and dry and retain their absorbent quality. Vhile ready for the next step in the process, they may, ii desired, be efiiciently and conveniontly handled, transported and stored. The final step, broadly, is the impregnating of the blocks with a fuel oil. For this purpose any low grade fuel oil may be employed. This impregnation is preferably etiected about the time of use.

The object therefore of this invention is to provide a process to increase the value and availability of peat as a fuel.

Other objects oi the invention will more fully appear from the following description. and the accompanying drawings and will be pointed out in the annexed claims.

In the accompanying drawings, there has been disclosed a structure designed to carry out the objects of the invention, but it is to be understood that the invention is not con fined to the exact features shown and described, as various changes may be made and other structures employed, within the reasonable scope of the invention.

In the drawings:

Figure l is a side elevation, partly in section of the digging and blocking machine and drying racks;

Fig. 2 is a vertical section through the blocking drum and adjacent chamber walls;

Fig. 3 is a side elevation partly in section of the oil bath device.

This novel process, broadly considered, comprises the formation of peat blocks direct y from the freshly dug peat, the drying of the formed blocks and the impregnation of the dried blocks with a fuel oil. paratus to carr out the complete process is disclosed in the accompanying drawings. The digging and blocking may be accomplished by separate mechanisms, but, herein, one piece of machinery is provided to effect the digging, the conveying to the blocking machine, the blocking, and the delivery to the drying racks. The digging and blocking machine is here shown as movably mounted-es upon a flat car 1, running upon a wide gage track. Obviously, other transportation means may be employed or the appliance may be stationary and adaptable to be removed and set up in another portion of the bog when one portion is worked out. A shovel 2 is mounted on a standard 3 in the usual manner and is actuated by means of a power unit. This unit may be of any convenient type and is here shown as a steam boiler 4t and engine 5. This'apparatus functions to excavate or dig the peat from the bog and to deposit the same upon a screen 6.

The screen is preferably carried by the upper portion of the blocking device and functions not only to permit surplus water to drain but affords opportunity for the removal or picking of branches, roots, logs or similar undesirable substances. Such substances may be directly utilized as fuel. The peat mass when upon the screen may also be-agitated to facilitate the manual picking and removal of such articles.

This blocking apparatus comprises an inclosed chamber or chute 7, leading from the screen 6 to the movable member by which the next step in the process is effected. This is the blocking step in which the peat mass is formed into separate, preferably rounded, blocks 8. Such movable member is disclosed herein as a revoluble drum 9 having a plurality of alined depressions in its circumference. These depressions or molds 10 receive the peat mass which slides from the screen 6 down the chute '7. This drum is actuated by any suitable power means which need not be shown, although, obviously, the power may be conveniently derived from the same power unit as that which actuates the An ap-.

digging device. The peat is forced, by the weight of the superposed mass, into the molds 10 as the drum revolvesas here disclosed, in a clock-wise oirection. The side ll (see Fig. 2) of the blocking chamber functions to cooperate with the drum to compress the peat in the molds. This compression is not great enough to force out a large amount of water but does serve to form the peat into blocks. The curvature of the inside face of the side 11 is eccentric with relation to the curvature of the drum periphery. This eccentricity is such that the lower portion 1; of this inside face is in closer proximity to the drum than is the upper portion ].I' hence, the peat mass in a given mold is in creasingly constricted and COIHPIOSSOd by the revolution of the driven drum. The molds 10 are so designed as to cause the formed blocks to present rounded edges. This is to obviate the crumbling and chipping tendency of sharp corners and edges as the blo rs are handled in transportation and storage or in transference to the combustion chamber.

The next step is to reduce the water content of the formed block. The block at this state of the process retains the major portion of its original moisture of the bog. This reduction is preferably achieved by drying in the open air. Air-drying will reduce the water content to that of the surroumling atmosphere. Artificial drying to a degree. below the moisture content of the atmosphere that of the atmosphere is, of course. possible but is expensive and such drying to a point below that of the atmosphere is useless because of the hygroscopic properties of peat which cause it rapidly to assume the humidity of the adjacent air. The blocks may be transferred from the blocking machine and dried upon the ground. But, they are preferably placed upon racks whereby they give up their water content more rapidly and occupy less area. A slide 14: is mounted on the shaft 15 of the drmn and causes the blocks 8, dropping from the molds of the revolving drum, to slide to the drying apparatus. This slide is shown as pivotall mounted so that it may assume a plurality of positions such as that partially shown by the dotted line in Fig. 1. The blocks may thus be directed to a lower tier if desired. In this embodiment there is disclosed a three-tier drying table or rack 16. The blocks are dropped into receptacles 17 having wire mesh sides and bases. Such construction of receptacles affords a ready circulation of air about the blocks. These blocks then dry into a firm, hard state without the crumbling and disintegrating tendencies of cut or briqucted peat. It is this process of treating the peat which results in these firm, hard, absorbciu blocks. In this state, the blocks may immediately be treated with the oil or may be transferred to a place of storage or to the point at which they are destined to be employed as a fuel where the next or oil step may be carried out.

The oil employed may be a relatively cheap, low grade fuel oil. If too viscous, it may be thinned by heating. The blocks may be caused to absorb the oil by any suitable means and the apparatus disclosed in Fig. 3 has proved a convenient mode of its accomplishment. Broadly, it consists of an endless conveyer running through an oil bath. An oil trough 18 is mounted upon standards 19. An oil supply intake 20 is provided for the replenishment of the oil. A heating pipe 21, preferably a steam-pipe, is positioned in the base of the trough and is provided with a connection 22 to the steam supply. The trough is longitudinally curved and is provided with flanges or short sides 23. The conveyer, in this embodiment, is of the endless belt type. The base may be of any suitably flexible, preferably reticulated material, such as a wire mesh belting. An endless metallic cable 24: is secured to each side of the mesh belting and to each of these cables is secured a plurality of short posts 25. These posts carry endless Wires 26 which serve as a side of the conveyer. The two sides function to retain the dry blocks 8 upon the base 24 as the conveyer travels through the oil trough 18. The conveyer is carried by the drums 27 and 28 and is preferably actuated by the drum 27 which moves in a clockwise direction. This permits the upper run of the conveyer to sag and thus, under weight of the received blocks, to travel with the conveyed blocks immersed in the oil in the curved trough. The trough is so mounted as to be vertlcally adjustable and to this end, the standards 19 are each adjustably supported by the uprights 29. Such adjustment of the oil trough permits of change of the immersion depth of the conveyer as desired. In carrying out this step, the blocks, when suitably dry, are removed from their receptacles or from the place of storage and deposited in the chute 30 whence they downwardly slide and may be continuously fed upon the traveling conveyer, as shown in Fig. 3. Emerging from the trough, the oil soaked blocks are dropped by the convcyer as it passes over thedrum 28 upon another chute 31 from which they are removed for use, sale, storage or other purpose.

The wet peat mass is thus converted into firm, hard blocks with rounded edges, and impregnated with a fuel oil. The oil functions in no sense as a binder, rather it may be conceived that the absorbent peat block functions as a wick for the oil. By the omission of the maceration step of the machine-peat, the absorbent property of this blocked peat is attained; for, the machine peat bricks are substantially non-absorbent when dry due to the maceration or pulping step with the attendant destruction of the fibrous and cellular structure. And, by the avoidance of the preliminary drying and the pulverizing steps in the briqueting process, the crumbling tendency and the friable nature of the peat briquet is obviated. Peat treated by this novel process has a high calorific value and the blocks are firm, hard and of such nature that they maybe success fully coked. They may be transported, stored and handled with great convenience and small. losses and in the combustion chamber they burn uniformly, steadily and continuously and with a very slight ash residue. During combustion, these blocks do not disintegrate and clog the fire but burn with a long uniform flame, with intense heat.

lVhile this blocking process is preferred it may be noted that the peat as cut from the bog and then air-dried may be impregnated with such heavy'fuel oil. Peat so treated does not have the hardness and tenacity of the blocked peat, and is therefore not economically transportable but may be used advantageously adjacent the source of peat supply, as for example, for the generation of various forms of energy, such as electric current.

It is to be understood that the process disclosed herein and the means for carrying it out are illustrative but not restrictive and that the same may be modified within the meaning and scope of the claims which follow.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent is:

1. The method of treating peat which consists in pressing the unmacerated peat into blocks, drying the blocks and then im pregnating the blocks with a fuel-oil.

2. The method of treating peat which consists in compressing the unmacerated peat into firm blocks, drying the blocks and immersing the blocks in a fuel-oil bath to impregnate the blocks with the oil.

3. The method of treating peat which consists in compressing the unmacerated peat into blocks, drying the blocks, heating a fuel-oil bath, and immersing the blocks in the heated bath to impregnate the blocks with the heated oil.

4. The method of treating peat which consists in screening and picking the peat mass to remove surplus water and foreign matter, compressing the unmacerated peat into blocks, drying the blocks and immersing the blocks in a heated fuel-oil bath to impregnate the blocks with the heated oil.

5. The method of treating peat which 0011 sists in digging peat, immediately transferring the peat mass to a screen to drain the surplus water and permit the removal of foreign matter, then pressing the peat mass into blocks, slowly drying the blocks on a rack in the open air and subsequently i1npregnating the blocks with an oil.

8. The method of treating peat which consists in compressing the unmaeerated pent into blocks, drying of the blocks, subsequently continuing the drying at atmospheric temperature and the impregnating 20 of the blocks with an oil.

In testimony whereof I have signed my name to this specification.

WESLEY \V. BLAIR.

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