RU2430846C2 - Method of operating steam locomotive on solid fuel - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to railway transport, particularly, to steam locomotives running on solid fuel. Proposed method comprises thermal decomposition of solid fuel into solid and gas phases, their separate combustion, feed of generated heat to boiler water, production of steam, steam overheating and feed into steam machine. Said method comprises the following stages. Solid fuel portion into combustion chamber for it to be decomposed into solid and gas phases. Thereafter, solid phase is fired in furnace. Has phase is combusted in furnace to increase steam generation by radiant steam superheater to increase steam temperature. Heat of gas phase combustion products is used to dry saturated steam of steam machine cylinder wall and accumulator water. Amount of combusted gas phase is used to adjust furnace heat rating. Heat transfer to boiler water is terminated in afterburning chamber to facilitate rate of reaction between combustible substances with oxidiser via temperature and concentration increase rate.

EFFECT: higher efficiency and lower steam consumption per unit power.

2 dwg

Description

The invention relates to the field of transport engineering and can be used in steam locomotives.

A known method of operation of a steam locomotive on solid fuel, including burning solid fuel in the furnace, transferring the resulting heat through the walls of the furnace and pipes to boiler water, converting it into steam, overheating it in a superheater, supplying steam to the cylinder of the steam engine and then turning it back through the moving mechanism - translational movement of the piston of the machine in the rotational movement of the wheels [1].

The disadvantages of this method are:

- low efficiency due to mechanical losses of fuel (through the slots of the grate and the entrainment of coal fines with combustion products), as well as chemical losses (underburning of fuel);

- low operational efficiency, due to the fact that with a sharp decrease in steam consumption by the steam engine (for example, in the case of a sudden stop), the heat produced by the furnace cannot be quickly reduced. As a result of this, the steam pressure in the boiler increases, the value of which is reduced by the release of steam into the atmosphere, while useful work is not performed and, therefore, the efficiency decreases;

- a relatively large steam consumption per unit of power produced, due to the low superheat temperature in the convection superheater and the decrease in the temperature of the steam when it enters the steam engine as a result of contact with the cold walls of the cylinder;

- the presence of harmful emissions into the atmosphere.

The prototype is a method of operating a steam locomotive on solid fuel, including burning solid fuel in the furnace and afterburning chamber, transferring the resulting heat through the walls of the furnace, afterburning chamber and boiler water pipes, turning it into steam, overheating it in a superheater, supplying steam to the cylinder of the steam engine and subsequent transformation through the driving mechanism of the reciprocating motion of the piston of the machine into the rotational movement of the wheels [2].

This method essentially has the same disadvantages as the previous one, although afterburning the fuel in the afterburner and transferring heat through it to the boiler water slightly increase the efficiency of the boiler and reduce the chemical underburning.

The objective of the invention is to remedy these disadvantages, namely increasing efficiency, reducing steam consumption per unit of production capacity and reducing harmful emissions into the atmosphere.

The problem is solved in that in the method of operating a steam locomotive on solid fuel, including burning fuel in a furnace, transferring the resulting heat to boiler water, receiving steam, overheating it in a convection superheater and feeding it to a steam engine, the fuel in the furnace is thermally decomposed into solid and gaseous phases that are burned separately.

The heat obtained by burning the gaseous phase is transferred to boiler water. The heat obtained by burning the gaseous phase is transferred to the superheated steam mainly by radiation before it is fed to the steam engine. The heat obtained by burning the gaseous phase is transferred to the superheated steam mainly by convection in the process of feeding it to the steam engine. The heat obtained by burning the gaseous phase is transferred to saturated steam. Heat transfer to boiler water is alternated with interruption. The combustion of the gas phase is carried out with a coefficient of excess air greater than is practically required. The increase in the amount of steam is carried out by supplying water with a temperature above the boiler, and the decrease with a temperature below the temperature of the boiler water. The amount of steam produced is controlled by the amount of gaseous phase burned. The heat obtained by burning the solid and gaseous phases is used to prepare water with a temperature higher than the temperature of the boiler water.

The prior art does not reveal solutions that have signs that match the distinguishing features of the claimed invention and have the same effect as they, on the technical result, which consists in increasing the efficiency, reducing the steam consumption per unit of power produced and reducing harmful emissions into the atmosphere.

The invention is reflected in the operations:

- in the furnace, the fuel is thermally decomposed into solid and gaseous phases, which are burned separately;

- the heat obtained by burning the gaseous phase is transferred to boiler water;

- the heat obtained during the combustion of the gaseous phase is transferred to the superheated steam mainly by radiation before it is fed into the steam engine;

- the heat obtained by burning the gaseous phase is transferred to the superheated steam mainly by convection in the process of supplying it to the steam engine;

- the heat obtained by burning the gaseous phase is transferred to saturated steam;

- heat transfer to boiler water alternate with interruption;

- combustion of the gas phase is carried out with a coefficient of excess air greater than is practically required;

- an increase in the amount of steam is carried out by supplying water with a temperature above the boiler, and a decrease with a temperature below the temperature of the boiler water;

- the amount of steam produced is controlled by the amount of gaseous phase burned;

- the heat obtained by burning the solid and gaseous phases is used to prepare water with a temperature higher than the temperature of the boiler water.

Thermal (pyrogenetic) decomposition of the fuel into solid and gaseous phases, which are burned separately, allows to increase the completeness of fuel combustion compared to the prototype, firstly, by reducing the mechanical entrainment of coal dust, which, when heated, goes into a plastic state and sticks to large pieces of the solid phase of the fuel (for example, to the resulting semi-coke). Secondly, the combustion of the heated (to the temperature of thermal decomposition) of the gaseous phase (volatiles) occurs much faster, therefore, a relatively small volume of the furnace is enough for the combustion of volatiles. It should be noted that by separate combustion is meant the combustion of a solid and gaseous phase with a separate oxidizing agent. For example, the solid phase is burned with a coefficient of excess air of 1.2, and the gaseous - 1.05. All this increases the efficiency of the boiler and reduces the amount of harmful emissions into the atmosphere.

The transfer of heat obtained during the combustion of the gaseous phase to boiler water increases the heat transfer due to the high emissivity of the torch and the possibility of obtaining directed heat transfer when using the effect of flatness of the torch. All this increases the efficiency of the boiler.

The transfer of heat obtained during the combustion of the gaseous phase to the superheated steam, mainly by radiation, before it is fed to the steam engine, makes it possible to increase the superheat temperature of the steam, for example, in a radiation superheater, as a result of which the steam consumption per unit of produced power is reduced.

The transfer of heat obtained during the combustion of the gaseous phase to the superheated steam mainly by convection in the process of supplying it to the steam engine makes it possible to more fully use the heat of the combustion products of the gas phase, directing them, for example, into a jacket covering the steam engine. Then the heat of the combustion products will compensate for the cooling of the cylinder of the steam engine, which occurs as a result of the expansion of steam in it. This contributes to an increase in efficiency and a decrease in steam consumption per unit of power produced. It should be noted that when burning ordinary coal or liquid fuel, significantly more solid particles and fine soot are formed than when burning gas, therefore, the products of combustion of the gas phase will not contaminate the jacket of the steam engine and other heat transfer elements.

The transfer of the heat obtained by burning the gaseous phase to the saturated steam allows you to evaporate the moisture in the saturated steam before it enters the superheater. As a result of this, it becomes possible to reduce the dimensions of the superheater or increase the superheat temperature of the steam, which reduces its consumption and increases the efficiency.

The alternation of heat transfer to boiler water with interruption allows during the interruption to increase the temperature of the combustion products, as a result of which all combustible particles and gases will burn out. At the same time, the oxidizing agent necessary for burning out can be taken from the excess air obtained by burning the gas phase with an excess air coefficient greater than is practically required. The combustion of combustible components contributes to additional heat generation, which increases the efficiency and reduces the amount of harmful emissions.

An increase in the amount of steam by supplying water with a temperature higher than the boiler, and a decrease with a temperature lower than the temperature of the boiler water allows, in the first case, if necessary, to briefly increase the steam production due to intensive boiling of the supplied water, and in the second, to prevent accidental release of steam into the atmosphere at rapid increase in steam pressure (for example, with a decrease in steam consumption) due to the cost of heat for heating cold water. All this contributes to increased efficiency.

Regulation of the amount of steam produced by the amount of gaseous phase burned makes it possible to control the boiler's steam capacity, which increases operational efficiency.

The use of heat obtained during combustion of the solid and gaseous phases for the preparation of water with a temperature above the temperature of the boiler water makes it possible to more fully use the heat of the combustion products, which increases the efficiency.

The invention is illustrated by drawings.

Figure 1 shows a diagram of a device that implements the method at the time of receipt of semi-coking gases. Figure 2 shows a diagram of a device that implements the method at the time of unloading of the semi-coke.

The device comprises a steam boiler 1 with heat pipes 2, in which superheater elements 3 are placed, connected by tubes 4 to elements 5 of the radiation superheater 6, which is connected through the heat exchange tubes 7 of the steam dryer 8 to the smoke box 9 and through the duct 10 to the jacket 11, covering cylinder 12 of the steam engine. Some ends of the chimneys exit into the chimney box, while others are connected through the afterburning chamber 13 to the firebox 14, in which the chamber 16 for thermal decomposition of fuel (for example coal) is mounted on the solid 17 and gaseous 18 phase, which through the distributor 19 Through gas pipelines 20 furnaces and 21 radiation superheaters enter the gas burners. The walls of the furnace and the chimneys are in contact with the boiler water 22, above which there is a steam space with saturated steam 23, communicating via a regulator 24, a steam line 25, a steam dryer, superheater elements and a manifold 26 with a cylinder of a steam engine, the shirt of which is connected to a smoke box through a channel 27 having a chimney 28. In the chimney box there is a steam dryer and accumulator 29, which is connected via a pipe 30 with valve 31 to a steam boiler.

The method is implemented as follows.

Download another portion of fuel, such as coal, in the chamber 16 (figure 1). As a result of the heat input, thermal decomposition of the fuel takes place and a gaseous phase 18 (volatile) is released from it, which enters the distributor 19 for subsequent combustion in gas burners. After the release of volatiles, the bottom of the chamber 15 is opened and the solid phase 17 (for example, semicoke) is burnt in the furnace 14 (Fig. 2). At the same time, small fractions of fuel during the heating process in the chamber become plastic, adhere to larger pieces and, when unloading the solid phase, are not carried away by flue gases and do not fall into the slots of the grate, which increases the efficiency.

The boiler water 22 is transferred the heat obtained by burning the gaseous phase, for which it is supplied to the gas burner 20 of the furnace. The combustion products of the solid and gaseous phases transfer their heat to the boiler water through the walls of the furnace and heat pipes 2, passing through them from the furnace to the smoke box 9. At the same time, part of the heat is removed by the steam moving inside the superheater elements 3 from boiler 1. Since these elements are surrounded by cold the shielding surface of the flame tubes, the temperature of the superheat of the steam is relatively low.

To increase the temperature of the steam, the heat obtained during the combustion of the gaseous phase is transferred to the superheated steam mainly by radiation, for which purpose the steam that is volatile into the burner 21 of the radiation superheater 6. The steam passing through the elements 5 of the radiation superheater is overheated to a higher temperature and then passes through the collector 26 to the cylinder 12 of the steam engine acting on the piston, the reciprocating movement of which through the crank mechanism is converted into rotational movement of the wheels of the locomotive (on rtezhe it not is shown).

During the movement of the piston in the cylinder, the steam expands and cools, while lowering the temperature of the walls of the cylinder. As a result, a fresh portion of the steam entering the cylinder irretrievably loses part of its heat to the heating of the cylinder walls. To eliminate this harmful phenomenon, the heat obtained by burning the gaseous phase (for example, from a radiation superheater) is transferred to the superheated steam mainly by convection, feeding it through the duct 10 to the jacket 11.

If saturated steam 23, containing, as a rule, 5-7% of water, is supplied directly to the superheater elements 3 through the regulator 24 and the steam line 25, then some of them will be used for drying the steam, as a result of which the temperature of the steam in this section will be constant ( equal to the temperature of saturated steam), while the effective area of the elements intended for superheating of the steam will decrease. Therefore, to increase the superheat temperature, the heat obtained during the combustion of the gaseous phase is transferred through the heat exchange tubes 7 of the steam dryer 8 to the saturated steam entering it.

Heat transfer to boiler water is alternated with interruption, for which they cease heat transfer in the afterburning chamber 13, covering its walls with a heat insulator. At the same time, the temperature of the gases in it rises, and the burning of combustible particles and gases occurs. Note, as a result of the narrowing of the flow in the afterburner, the concentration of reacting substances increases, which has a beneficial effect on the combustion reaction. Burning substances produce additional heat, increasing the temperature of the combustion products and improving heat transfer in the flame tubes.

Since an oxidizing agent is needed for the burning of substances, the gas phase is burned with a coefficient of excess air greater than is practically required. At the same time, part of the air consumed during the combustion of the gas phase is used for burning substances.

In the case of reducing the need for steam, part of the boiler water can be sent through the pipe 30 to the accumulator 29 and the valve 31 is closed, and cold water can be added to the boiler. In this case, the heat of the combustion products will be spent on heating cold water, and the amount of steam produced by the boiler will decrease. The combustion products of the solid and gaseous phases are directed through the channel 27, pipes 7 and heat pipes 2 into the smoke box and used to prepare water in the accumulator with a temperature higher than the temperature of the boiler water. After heat is transferred to the accumulator, the products leave the chimney box through the exhaust pipe 28. If the demand for steam increases, the valve is opened, and water from the accumulator flows into the boiler, the pressure of which is lower than in the accumulator. As a result of this, intense boiling of water flowing out of the accumulator occurs and vaporization increases. Thus, an increase in the amount of steam is carried out by supplying water with a temperature above the boiler, and a decrease with a temperature below the temperature of the boiler water.

During operation, the load on the locomotive changes. Since it is impossible to quickly increase and even lessen the flow of heat produced during the combustion of the solid phase, the heat generated in the furnace and, consequently, the amount of steam produced are controlled by the amount of gaseous phase burned.

The implementation of the invention will increase the efficiency of the locomotive, reduce steam consumption per unit of power produced and reduce the amount of harmful emissions into the atmosphere. Obviously, to facilitate the work of the locomotive crew, the operation of the boiler must be automated.

Information sources

1. Khmelevsky A.V., Smushkov P.I. Steam locomotive (device, work and repair). - M .: Transport, 1973. S.7-9 - analogue.

2. Syromyatnikov S.P. Thermal process of a steam locomotive. - M .: State Transport Railway Publishing House, 1940. S.137-140 - prototype.

Claims (9)

1. The method of operation of a steam locomotive on solid fuel, including decomposing the fuel into solid and gaseous phases, which are burned separately, burning the solid phase in the furnace, transferring the received heat to boiler water, generating steam, overheating it in a superheater and feeding it to a steam engine, characterized in that the heat obtained by burning the gaseous phase of the fuel is transferred to the resulting steam. 2. The method according to claim 1, characterized in that the heat obtained by burning the gaseous phase is transferred to the superheated steam before it is supplied to the steam engine mainly by radiation. 3. The method according to claim 1, characterized in that the heat obtained by burning the gaseous phase is transferred to the superheated steam during the movement of the piston of the steam engine, mainly by convention. 4. The method according to claim 1 or 3, characterized in that the heat obtained during the combustion of the gaseous phase is transferred by means of heat exchange tubes to saturated steam. 5. The method according to claim 1, characterized in that the heat transfer to the boiler water is alternated with interruption. 6. The method according to claim 1, characterized in that the combustion of the gaseous phase is carried out with a coefficient of excess air greater than is practically required. 7. The method according to claim 1, characterized in that the increase in the amount of steam is carried out by supplying water to the boiler with a temperature higher and the decrease with a temperature below the temperature of the boiler water. 8. The method according to claim 1, characterized in that the amount of steam produced is controlled by the amount of gaseous phase burned. 9. The method according to claim 1, characterized in that the heat obtained by burning the solid and gaseous phases is used to prepare water with a temperature higher than the temperature of the boiler water.

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