SU1988A1 - Mechanical furnace grate with part inclined moving, part motionless grate elements - Google Patents

Description

The proposed mechanical combustion grate is intended for such furnaces in which fuel is automatically fed to the grate and the slag is automatically removed to the slag gas, and is intended to make the furnace universal in terms of the possibility of proper and perfect combustion of various grades of solid fuel, such as: coal , anthracite, coke, shale, raw peat, sawdust, shavings, tanning waste, etc. - especially ensure timely and reliable ignition and perfect combustion of difficult combustible fuels, that, with modern fireboxes, it is not achieved because, mainly, the speed of movement of fuel along the grill, depending, as is well known, on often varying load conditions of the grill, usually much higher than the speed of the fuel back fire, as a result of this ratio, the ignition zone over time, it moves farther and farther toward the rear end of the lattice to the place where radiation from the surrounding heated walls and vaults facilitates fuel combustion. In order to ensure timely (at the beginning of the grid) the ignition of difficult-to-ignite solid fuel grades and to achieve uniform burning of that on the entire grid, it is proposed, according to the present invention, to arrange on the grids, at small distances from each other, several transverse projections or thresholds to hold the lower layers of the fuel and to provide the upper layers with freedom of movement by moving through these thresholds. This upward movement of the bottom surface of the fuel pieces is especially important, for example, when burning shale, which, as is known, burns only from above. Foci form between these protrusions or thresholds, of which the former serve to ensure the ignition of the fuel, and further to contain and accumulate relatively thin protective layers of scrap. Such a device makes it possible to burn on the same grate.

varying degrees of flammability — grades of solid fuel, because if at a given rate of advancement of a given fuel along the grid, this fuel does not ignite above the first or even above the second hearth, then this ignition will follow the rest. Under normal operating conditions, ignition occurs already in the first or first foci, and in further foci, a low layer of slag will be deposited, which in these places of the lattice does not only interfere with the correct combustion process, but is useful in the sense that it protects Grate bars from burning through.

The drawing shows various embodiments of the invention, with FIG. 1 and 2 relate to a mechanical firebox with inclined longitudinal grates, of which only part receives reciprocating movements; FIG. 3 - to the inclined grate with cross bars and, finally, FIG. 4 depicts a modification in the device details.

In the device of FIG. 1, both moving and fixed grates 7, supported on girders O and 6, are provided with a number of transverse protrusions 2, forming thresholds for retaining the lower layers of fuel in foci 3, 3 3 ... First hearth 3 limited in front (solid or composite) plate 4, on which the piston / / promotes fresh portions of fuel and is made so large that it always contains a significant amount of burning fuel, but in no way could slag accumulate. The shape of the protrusions 2 and the distance between them depend mainly on the method of supplying coal to the grate and on the inclination of the latter, and these shapes and distances are chosen so that in the first hearths (for example, in the first two or three hearths) the burning layer of fuel lasted longer, but the slag would not accumulate. Due to the use of several relatively small foci 3, 3, 3, there is no need to select the exact outline and size of the thresholds 2, because in the first

there will be no slag foci, and in the remaining slag itself forms a concave surface for moving the incandescent combustible material - different for different types of fuel. In all cases, the front surface of the thresholds 2 should have a steep slope, and the rear should, on the contrary, be relatively very sloping.

The thresholds 2 of the moving grates / (figs. 1 and 2), when the latter are set up in the common plane of the grid, pull back the lower part of the burning layer of fuel, without interfering with the forced advancement or free sliding down of its upper layers. A similar phenomenon occurs with furnaces arranged in FIG. 3, i.e. having an inclined lattice of transverse moving and stationary grates, provided at the lower edge with transverse thresholds or protrusions 2.

As you approach the rear end of the grille, the protrusions 2 of the grate 7 can, with a known inclination of the lattice, obtain both a smaller height and a flatter form (Fig. 1), because in these steps the effect of the piston / 7 feeding the fuel is less than in the first half of the lattice.

Instead of a series of separate thresholds 2 on the rear half of the lattice, it is possible, as shown in FIG. 2, apply the grate 7, having here more or less significant, but smooth bend 1 upwards, i.e. Such grates, which slope, starting approximately from the middle, decrease first, and then be brought back to normal by the end, or even made more significant, to paralyze the braking effect of the lower ends of the fixed grate. The beam b supporting the rear ends of the grate can also be stacked so that by moving it up and down you can change the overall inclination of the grid. The bending of the grate in the second half, indicated in FIG. 2, can be calculated using the thresholds 2 and on these rear portions of the grate. olosnik lattice of FIG. 3 can also be designed in such a way that its surface in the rear half has a smooth curve upwards. Level plate 4 (Fig. 1) or its front part should be made of individual tiles 74 Sfig. 4), supported at the rear end by a hook 75, pivoted and freely lying with the front edge on the bottom of the first chamber 3. With such a device, accuracy in the assembly is not required and it is possible to remove slag from this chamber if such has accumulated here for some reason. Such a device, moreover, makes it possible to eliminate, without resorting to any alterations, the first hearth 3 in the case when it is necessary to burn gas rich in gas and easily sintering fuel, which at high temperature could form a stopper in the narrow throat of the firebox. that would lead to stopping work. To do this, it will be enough to reinforce the plate (or plates) 73 on the bottom of this first chamber 3, on which (or which) the front edges of the respectively raised plates 74 will lie, with the first center of the Wits grate 3. The same The device can also be used for the first grate of FIG. 3. 1. Mechanical furnace grate with inclined part moving, part motionless grate elements, characterized in that it is provided on said elements along their entire length (Fig. 1, 3) or only on their front part (Fig. 2) p The house of transverse protrusions (thresholds) 2, forming a series of successive recesses (hearths) 3 3, designed to hold the lower burning layers of fuel, in order to promptly ignite the main layer of solid fuel advancing above them. 2. The form of implementation of the lattice indicated in claim 1, characterized in that the height of the projections 2 on its elements is made gradually decreasing towards the rear end thereof (Fig. 1). 3. When specified in pp 1 to 2 lattice application of pivotal leveling tiles 74 (Fig. 4), supported by a free end on a corresponding grate element. 4.When specified in pp 1 to 3 of the lattice, the use of inserts 73 (Fig. 4) to eliminate or reduce the first recess (hearth) located at the beginning of the lattice. SUBJECT OF THE PATENT.

Tipo-pitography with Red Pechatnik, Leningrad, International, 75..