Peat and its Uses as Fertilizer and Fuel - Part 14
Library

Part 14

In the third method the peat-ma.s.s falls from the mill into a hopper, which directs it between the rolls _A B_ of fig. 11, (see next page).

The roll _A_ has a series of boxes on its periphery _m m_, with movable bottoms which serve as moulds. The peat is carried into these boxes by the rolls _c c_. The iron projections _n n_ of the large roll _B_, which work cog-like into the boxes, compress the peat gently and, at last, the eccentric p acting upon the pin _z_, forces up the movable bottom of the box and throws out the peat-block upon an endless band of cloth, which carries it to the drying place.

The peats which are dried at first under cover and therefore slowly, shrink more evenly and to a greater extent than those which are allowed to dry rapidly. The latter become cracked upon the surface and have cavities internally, which the former do not. This fact is of great importance for the density of the peat, for its usefulness in producing intense heat, and its power to withstand carriage.

[Ill.u.s.tration: Fig. 11--WEBER'S PEAT MOULDING MACHINE.]

The _complete drying_ is, on the other hand, by this method, a much slower process, since the dense, fissureless exterior of the peats hinders the escape of water from within. It requires, in fact, several months of ordinary drying for the removal of the greater share of the water, and at the expiration of this time they are still often moist in the interior.

Artificial drying is therefore employed to produce the most compact, driest, and best fuel.

Weber's _Drying house_ is 120 feet long and 46 feet wide. Four large flues traverse the whole length of it, and are heated with the pine roots and stumps which abound in the moor. These flues are enclosed in brick-work, leaving a narrow s.p.a.ce for the pa.s.sage of air from without, which is heated by the flues, and is discharged at various openings in the brick-work into the house itself, where the peat is arranged on frames. The warm air being light, ascends through the peat, charges itself with moisture, thereby becomes heavier and falls to the floor, whence it is drawn off by flues of sheet zinc that pa.s.s up through the roof. This house holds at once 300,000 peats, which are heated to 130 to 145 F., and require 10 to 14 days for drying.

The effect of the hot air upon the peat is, in the first place, to soften and cause it to swell; it, however, shortly begins to shrink again and dries away to ma.s.ses of great solidity. It becomes almost h.o.r.n.y in its character, can be broken only by a heavy blow, and endures the roughest handling without detriment. Its quality as fuel is correspondingly excellent.

The effects of the mechanical treatment and drying on the Staltach peat, are seen from the subjoined figures:

_Lbs.

_Specific per Cubic _Per cent of Gravity._ Foot._ Water._

Peat, raised and dried in usual way, 0.24 15 18 to 20 Machine-worked and hot-dried 0.65 35 12

Vogel estimates the cost of peat made by Weber's method at 5 Kreuzers per (Bavarian) hundred weight, while that of ordinary peat is 13-1/2 Kreuzers. Schroeder, in his comparison of machine-wrought and ordinary peat, demonstrates that the latter can be produced much cheaper than was customary in Bavaria, in 1859, by a better system of labor.

Weber's method was adopted with some improvements in an extensive works built in 1860, by the Government of Baden, at Willaringen, for the purpose of raising as much fuel as possible, during the course of a lease that expired with the year 1865.

[Ill.u.s.tration: Fig. 12.--GEYSSER'S PEAT MACHINE.]

_Gysser's method._[25]--Rudolph Gysser, of Freiburg, who was charged with the erection of the works at Willaringen just alluded to, invented a portable hand-machine on the general plan of Weber, but with important improvements; and likewise omitted and varied some details of the manufacture, bringing it within the reach of parties of small means.

In the accompanying cuts, (figs. 12, 13, and 14), are given an elevation of Gysser's machine, together with a bird's-eye view and vertical section of the interior mechanism.

[Ill.u.s.tration: Fig. 13.]

[Ill.u.s.tration: Fig. 14.]

It consists of a cast iron funnel _c d i_ of the elevation, (fig. 12), having above a sheet iron hopper _a b_ to receive the peat, and within a series of six knives fastened in a spiral, and curving outwards and downwards, (figs. 13 and 14); another series of three similar knives is affixed to a vertical shaft, which is geared to a crank and turned by a man standing on the platform _j k_; these revolving knives curve upwards and cut between and in a direction contrary to the fixed knives; below the knives, and affixed to the shaft a spiral plate of iron and a sc.r.a.per _m_, (fig. 13), serve to force the peat, which has been at once minced and carried downwards by the knives, as a somewhat compressed ma.s.s through the lateral opening at the bottom of the funnel, whence it issues as a continuous hollow cylinder like drain-tile, having a diameter of four inches. The iron cone _i_, held in the axis of the opening by the thin and sharp-edged support _g h_, forms the bore of the tube of peat as it issues. Two men operate the machine; one turning the crank, which, by suitable gearing, works the shaft, and the other digging and throwing in the peat. The ma.s.s, as it issues from the machine, is received by two boys alternately, who hold below the opening a semi-cylindrical tin-plate shovel, (fig. 15), of the width and length of the required peats, and break or rather wipe them off, when they reach the length of 14 inches.

[Ill.u.s.tration: Fig. 15.]

[Ill.u.s.tration: Fig. 16.]

The formed peats are dried in light, cheap and portable houses, Fig. 17, each of which consists of six rectangular frames supported one above another, and covered by a light roof. The frames, Fig. 16, have square posts at each corner like a bedstead, and are made by nailing light strips to these posts. The tops of these posts are obtusely beveled to an edge, and at the bottom they are notched to correspond. The direction of the edges and of the notches in two diagonally opposite posts, is at right angles to that of the other two. By this construction the frames, being of the same size, when placed above each other, fit together by the edges and notches of their posts into a structure that cannot be readily overturned. The upper frame has a light shingled roof, which completes the house. Each frame has transverse slats, cast in plaster of Paris, 20 in number, which support the peats. The latter being tubular, dry more readily, uniformly, and to a denser consistence than they could otherwise.

The machine being readily set up where the peat is excavated, the labor of transporting the fresh and water-soaked material is greatly reduced.

The drying-frames are built up into houses as fast as they are filled from the machine. They can be set up anywhere without difficulty, require no leveling of the ground, and, once filled, no labor in turning or stacking the peats is necessary; while the latter are insured against damage from rain. These advantages, Gysser claims, more than cover their cost.

[Ill.u.s.tration: Fig. 17.]

The daily production of a machine operated by two men with the a.s.sistance of one or two boys, is 2500 to 3000 peats, which, on drying, have 9-1/2 to 10 inches of length, and 2-1/2 in diameter, and weigh, on the average, one pound each.

c.--_Condensation of peat of all kinds._--_Weber's method with modified machinery._

[Ill.u.s.tration: Fig. 18.--SCHLICKEYSEN'S PEAT MILL.]

_Schlickeysen's Machine._[26]--This machine has been in use in Germany since 1860, in the preparation of peat. It appears to have been originally constructed for the working and moulding of clay for making bricks. The principle of its operation is identical with that of Weber's process. The peat is finely pulverized, worked into a h.o.m.ogenous ma.s.s, and moulded into suitable forms. Like Gysser's machine, it forces the peat under some pressure through a nozzle, or, in the larger kinds through several nozzles, whence it issues in a continuous block or pipe that is cut off in proper lengths, either by hand or by mechanism It consists of a vertical cylinder, through the axis of which revolves a shaft, whereon are fastened the blades, whose edges cut and whose winding figure forces down the peat. The blades are arranged nearly, but not exactly, in a true spiral; the effect is therefore that they act unequally upon the ma.s.s, and thus mix and divide it more perfectly. No blades or projections are affixed to the interior of the cylinder.

Above, where the peat enters into a flaring hopper, is a sc.r.a.per, that prevents adhesion to the sides and gives downward propulsion to the peat. The blades are, by this construction, very strong, and not liable to injury from small stones or roots, and effectually reduce the toughest and most compact peat.

Furthermore, addition of water is not only unnecessary in any case, but the peat may be advantageously air-dried to a considerable extent before it enters the machine. Wet peat is, indeed, worked with less expenditure of power; but the moulded peats are then so soft as to require much care in the handling, and must be spread out in single courses, as they will not bear to be placed one upon another. Peat, that is somewhat dry, though requiring more power to work, leaves the machine in blocks that can be piled up on edge and upon each other, six or eight high, without difficulty, and require, of course, less time for curing.

The cut, (fig. 18), represents one of Schlickeysen's portable peat-mills, with elevator for feeding, from which an idea of the pulverizing arrangements may be gathered.

In Livonia, near Pernan, according to Leo, two of Schlickeysen's machines, No. 6, were put in operation upon a purely fibrous peat. They were driven by an engine of 12 horse-power. The peat was plowed, once harrowed, then carted directly to the hopper of the machine. These two machines, with 26 men and 4 horses, produced daily 60,000 peats = 7500 cubic feet. 100 cubic feet of these peats were equal in heating effect to 130 cubic feet of fir-wood, and cost but two-thirds as much. The peats were extremely hard, and dried in a few days sufficiently for use.

In 1864, five large Schlickeysen machines were in operation at one establishment at St. Miskolz, in Hungary.

The smaller sizes of Schlickeysen's machine are easily-portable, and adapted for horse or hand-power.

_Leavitt's Peat-condensing and Moulding Mill._[27]--In this country, Mr.

T. H. Leavitt, of Boston, has patented machinery, which is in operation at East Lexington, Ma.s.s., at the works of the Boston Peat Company. The process is essentially identical with that of Weber, the hot-drying omitted. The fresh peat is pulverized or cut fine, moulded into blocks, and dried on light frames in the open air. The results claimed by Mr.

Leavitt, indicate, that his machine is very efficacious.

It consists, princ.i.p.ally, of a strong box or cistern, three feet in diameter, and six feet high, the exterior of which, with its gearing, is shown in figure 19. The mill is adapted to be driven by a four horse-power engine.

"The upper portion of the box is divided by a series of horizontal part.i.tions, the upper ones being open latticework, and the lower ones perforated with numerous holes. The upright shaft, which rotates in the centre of the box, carries a series of arms or blades, extending alternately on opposite sides, and as these revolve, they cut the peat, and force it through the openings in the diaphragms. The lower portion of the box, in place of complete part.i.tions, has a series of corrugated shelves extending alternately from opposite sides, and the peat is pressed and sc.r.a.ped from these by a series of arms adapted to the work.

By this series of severe operations the air-bubbles are expelled from the peat, and it is reduced to a h.o.m.ogeneous paste. When it arrives at the bottom of the box, it is still further compressed by the converging sides of the hopper, and it is received in light moulds which are carried on an endless belt." Mr. Leavitt has patented the use of powdered peat for the purpose of preventing the prepared peat from adhering to the moulds.

[Ill.u.s.tration: Fig. 19.--LEAVITT'S PEAT MILL.]

This mill, it is a.s.serted, will condense 40 tons of crude peat daily, which, at Lexington, is estimated to yield 10 to 14 tons of dry merchantable fuel. The cost of producing the latter is a.s.serted to be less than $2.00 per ton; while its present value, in Boston, is $10 per ton. It requires seven men, three boys, and two horses to dig, cart, mill, and spread the peat. The machine costs $600, the needful buildings, engine, etc., from $2000 to $3000. The samples of peat, manufactured by this machine, are of excellent quality. The drying in the open air is said to proceed with great rapidity, eight or ten days being ordinarily sufficient in the summer season. The dry peat, at Lexington, occupies one-fourth the bulk, and has one-fourth to one-third the weight of the raw material; the latter, as we gather, being by no means saturated with water, but well drained, and considerably dry, before milling.

_Ashcroft & Betteley's Machinery._

The American Peat Company, of Boston, are the owners of five patents, taken out by Messrs. Ashcroft & Betteley, for peat machinery. They claim to "make fuel equal to the best English Cannel coal," and really do make a very good peat, though with a rather complicated apparatus. The following statement is derived from the circular issued by the company.

The machinery consists of the following parts:--

_First._--TRITURATING MACHINE--36 inches diameter, 4 feet 6 inches high, with arms both on the inside of this cylinder and on the upright revolving shaft. In the bottom of the cylinder or tub a large slide gate is fitted to work with a lever, so that the peat may be discharged, at pleasure, into the Combing Machine, which is placed directly under this Triturator.

_Second._--COMBING MACHINE--Semi-circular vessel 6 feet long and 3 feet 6 inches in diameter. Inside, a shaft is placed, which is provided with fingers, placed one inch apart; the fingers to be 20 inches long, so as to reach within 2 inches of the bottom and sides of this vessel. Another shaft, of the same size and dimensions, is placed at an angle of 45, 26 inches from the first shaft, with arms of the same dimensions placed upon this shaft, with the same s.p.a.ces, and so placed that this set of arms pa.s.s between the first set, both shafts revolving in the same direction; the second shaft mentioned being driven at double the speed of the first. At the bottom of this Combing Machine is to be fixed a gate, to be operated by a lever, to deliver, at pleasure, the cleansed peat into the Manipulator or Kneading Machine.

_Third._--MANIPULATOR.--A Tube of iron 7 feet long and 16 inches diameter, fitted with a shaft, with f.l.a.n.g.es upon it, to gain 6 inches in each revolution.

_Fourth._--CONVEYOR.--This Conveyor, to be made with two endless chains and buckets of iron, with a driving shaft. The hopper, to receive the peat when first taken from the bog, to be placed below the surface of the ground, so that the top edge of the hopper may be level with the surface, that the peat may be dumped from the car by which it is taken from the bog, and carried to the hopper without hand labor; and this conveyor to be so arranged that the peat will be delivered into the Triturator without hand labor.

_Fifth._--CONVEYOR.--Another conveyor, precisely like the one above described, is to be placed so as to convey the peat from the Manipulator into the Tank without hand labor.

_Sixth._--TANK.--A tank 35 feet high and 15 feet in diameter; the bottom of this tank is made sloping towards the sides, at an angle of 65, and is covered with sole tile or drain tile, and the entire inside of this tank is also ribbed with these tile; the ends of these pipes of tile being left open, so that the water which percolates through the pores of the tile, by the pressure of the column of peat, will pa.s.s out at the bottom, through the false floor of the tank into the drain, and the solid peat is retained in the tank. A worm is fixed in the bottom of this tank, which is driven by machinery, which forces out the peat in the form of brick, which are cut to any length, and stacked up in sheds, for fuel, after it is fully dried by the air.

[Ill.u.s.tration: Fig. 20.--VERSMANN'S PEAT PULVERIZER.]