WO2012128654A1 - Method for heating the fireproof lining of a coke oven battery - Google Patents

Abstract

The invention relates to the field of the by-product coke industry. A method for heating the fireproof lining of a battery of coke ovens is proposed, according to which the heating gas used is liquid propane-butane which is first of all subjected to regasification in an evaporator-type heat exchanger and is then fed to burners, each of which is equipped with a shield and is mounted in a temporary internal furnace in each coke oven on the mechanical and coke oven side of the battery, wherein a controllable air flow is fed into the furnace through a kindling aperture formed in the front of the temporary internal furnace, wherein the quantity of air fed into the furnace is controlled with the aid of movable flaps which are mounted in the kindling apertures and make it possible to adjust the free area of the kindling aperture during the heating process, and the specified heating temperature regime is maintained by controlling the oven draught and the consumption of propane-butane fed to the burners. The invention ensures uniform heating of the lining in the absence of external furnaces.

Description

 The method of heating the refractory masonry of a coke oven battery

Technical field

 The invention relates to the field of coke chemistry, and can be used for heating and commissioning of coke oven batteries using liquefied propane-butane. Heating the coke oven battery with liquefied gas (propane-butane) is mainly used when commissioning the head (first) of the coke oven battery at a single enterprise, while there are either no other sources of gas supply for heating, or they are not available in sufficient quantity.

State of the art

In the construction of coke oven batteries, refractory materials such as dinas and fireclay are used, which together with high thermal conductivity have a large coefficient of thermal expansion. When dinas is heated from ambient temperature to operating temperatures, the level of which is from 1150 to 1450 ° С, modifications of quartz (silicon dioxide, Si0 ₂ ) pass from one to another with a change in the crystal lattice and the volume of the product. The change in volume can be from 0.1% to 3.0%. Structural transformations of quartz in dinas products occur in the temperature range 1 17 ° C, 163 ° C, 230 ° C, 573 ° C, 870 ° C and can violate their strength. At a large thermal expansion of dinas at the stage of low-temperature (below 300 ° C) transformations of quartz and its modifications (tridymite and especially cristobalite), dinas is thermally unstable. These circumstances require the use of a special heating technology that allows you to strictly maintain a given technological mode for raising the temperature of the refractory masonry of coke oven furnaces. Depending on the modification (phase-structural) degenerations of the dinas, the average daily temperature increase of the refractory masonry should be strictly observed according to the stages of heating. Depending on the specific stage of heating, it is from about 5 to 50 ° C per day.

After the completion of the construction of coke oven batteries or after major cold repair (reconstruction), it is required to heat their refractory masonry to operating temperatures. The fuel for heating the coke oven battery can be various types of gases: coke, natural, blast furnace, generator. During the construction of new coke plants, when it is not possible to heat the first (head) coke oven battery with its own gas, it is proposed to heat it with natural or liquefied gas (propane-butane).

 The use of the option of heating a coke oven battery with liquefied gas (propane-butane) with its preliminary mixing with air when a previously prepared gas-air mixture is fed to the burner is dangerous and difficult for the following reasons:

 - 2 - ^ - 3 degrees of protection against the event of a plant explosion in case of violation of the gas-air mixture ratio are required;

 requires a complex and expensive system for preparing a gas-air mixture and protection against cases of flame penetration deep into the burner or flame separation;

 - the cost of the gas transportation system rises due to an increase in the diameters of the gas-air mixture pipelines compared to the diameter of the gas pipelines themselves;

 A known method of heating furnaces using internal gas burners.

For example, a known method of drying and heating vertical chamotte and dinas chambers 11 000074

4 shale furnaces (SU 136508, 1961). The method involves heating the furnaces using an injection gas burner installed in the lower part of the chamber.

 However, the known method cannot provide a safe and high-quality heating of the coke oven battery, for example with propane-butane, since at minimum gas flow rates at the initial stage of heating, when air injection due to the gas jet is not provided within the limits necessary for high-quality and complete (smokeless) combustion of the heating gas , soot clogging of the nozzles of the regenerators occurs and the disorder of the battery heating process.

A known method of heating the refractory masonry of a coke oven battery using a gaseous coolant, the use of compressed air is recommended, the coolant is supplied to the heating channels and heated by heat exchange through the heat of the hot nodes of the coke oven battery, and the masonry is heated using a gaseous coolant to a temperature of 250 ° C during high-altitude masonry, and the heating of new heating canals are produced up to a temperature of 500 ° C immediately after completion of masonry construction works (RU 2062282, 1996).

 The known method is not convenient to use, since partial heating has to be done during the repair process, during the laying of the furnace.

Disclosure of invention

 The objective of the present invention is to ensure uniform heating of the refractory masonry of coke oven batteries with a limited selection of coolants, and without the use of external furnaces.

The problem is solved by the described method of heating the refractory masonry of the coke oven battery, including supplying heating gas to the coke oven chambers and heating in accordance with a predetermined temperature regime, in which liquefied propane butane is used as heating gas, the liquefied gas is first subjected to regasification in the evaporator-heat exchanger, then fed to the burners, each of which is equipped with a screen, and installed in the temporary internal furnace of each coke oven from the machine and coke sides of the battery, this through a kindling window made in the facade of the temporary internal firebox, a regulated air flow is supplied into the firebox in an amount necessary and sufficient for stable combustion of the propane butane torch during the entire heating process, moreover, the amount of air supplied to the firebox is regulated using movable dampers installed in the kindling windows, and providing the possibility of changing the free area of the kindling window during the heating process, the specified temperature mode of heating is maintained by adjusting the furnace traction and the flow rate about to propane-butane burners.

 Preferably, the heating is carried out for 65-70 days to a temperature of 1000 - 1050 ° C.

Preferably, the rate of temperature rise during heating is 5.5-6.5 ° per day during the first 32 days, 9 ° per day during the 33rd to 35th days, and the 39th during the 36th period days 12 ° per day, during the 40s - 44th days 15 ° per day, during the 45s - 47th days 18 ° C, during the 48th - 50th days 21 ° per day, in the period of 51st - 59th day 24 ° C, in the period of 60th - 62nd day 32 °, in the period of 63-64 days 36 ° per day and then at a speed of 48 ° per day until the output to the specified mode . The claimed method can be implemented, for example, using devices, the design and installation diagram of which is illustrated below.

Brief Description of the Drawings

 Figure 1 - temporary internal firebox, laid out of fireclay bricks inside each coking chamber of the heated battery;

 Figure 2 - burner for burning propane butane in the internal furnace, installed in each furnace from the machine and coke side of the battery;

 FIG. 3 - Burner with a screen made in the form of a stainless steel mesh;

 Figure 4 - movable damper that regulates the air supply, placed in the kindling window in front of each burner;

 Figure 5 is a General view of the node supplying gas to a temporary furnace.

The best example of carrying out the invention

In each particular case of heating, the following process parameters are calculated depending on the volume of the refractory masonry of the coke oven battery: - heating gas costs for the heating stages (for one burner and for the whole battery, calculated on the basis of the known need for energy consumption to maintain a given temperature increase and calorific value of liquefied propane butane);

 - diameters of the supply and distribution pipelines within the entire unit;

 - diameters of the burner pipes;

 - diameters and number of holes in the perforated part of the burner.

 With appropriate calculations, the necessity of heating the chimney to create traction and discharge in the side burs of the battery is also taken into account.

At the preparatory stage, a warehouse is being built to store the required amount of liquefied propane-butane and a unit for its regasification, including evaporators and heat exchangers for transferring the coolant from a liquid to a gaseous state. Produces the manufacture of accessories and equipment, including burners and dampers. Temporary masonry configuration internal firebox does not depend on the type of heat carrier used.

 A general view of the temporary masonry of the internal firebox is shown in Fig. 1, while under p. 1 the furnace hearth is indicated, p. 2 is the furnace arch line, and the input sections of the kindling windows of p. 3 are possibly increased, based on the design features of the stoves of a specific battery . At the stage of preparatory work, a temporary gas supply pipeline for gas supply for heating the battery from the regasification unit to the chimney and to the battery from the machine and coke side is mounted. In the furnace of the coke oven battery, burners of a special design are installed through the windows provided for them in the internal furnaces of p.

 The design of the burner used, illustrated in figure 2, item 4, is quite simple and is a welded structure of pipes of various diameters.

The implementation of the method is illustrated below. Heating gas (propane-butane) from a temporary gas pipeline, connected to the coking chamber to be heated, enters the main burner tube, p. 5, which is connected to the gas supply from the temporary gas pipeline of p. 6 by means of a flange connection of claim 7 and is parallel to the axis of the coking chamber, and from which in the plane parallel to the bottom of the coking chamber and passing through the axis of the main tube, two outlet pipes of a smaller diameter of clause 8, which serve to supply gas directly to gas outlet pipes of claim 9, parallel to each other and perpendicular to the plane of the hearth of the coking chamber, in which small-diameter gas outlet holes of claim 10 are drilled in a row one below the other coaxial to the gas outlet pipe, so that the jet of exhaust gas was directed towards the axis of the main tube. At the same time, plugs, item 11, are hermetically welded at the free ends of the main and exhaust pipes.

 A directed air flow is fed into the firebox, which cuts the gas stream of the burner, and provides the mixture of gas and air required for high-quality combustion due to the intersection of the air stream with the gas stream.

It should be noted that after each burner is installed in the coking chamber, but before heating starts, a screen is hung (see Fig. 3, item 12), which is a rectangle of metal mesh (mainly stainless steel) bent in three places parallel to one of its faces so that it rests under the force of its own weight into the ends of the exhaust pipes of the burner of item 9 closed by plugs 11, looking up and pressed against both gas exhaust pipes of the burner of item 9 from the side of the burner looking deep into the coking chamber below all gas outlets of clause 10. With this arrangement, during heating, the screen will be constantly in a red-hot state from the burning torch, and if the torch suddenly goes out (is blown out), the stream of raw gas will ignite again in contact with the red-hot screen grid and combustion will resume. The required level of air flow, at which sufficient air is supplied from the external environment for stable flame burning, is ensured by closing the windows in the internal furnaces of section 3 with the movable dampers shown in Fig. 4: into the masonry of the facade of the temporary firebox between the rows of bricks forming the lower and the upper boundary of the kindling window of p. 3, respectively, the upper guide p. 13.1 and the lower support-guide p. 13.2 are installed metal corners. In this case, between the upper and lower corners of paragraph 13.1 and paragraph 13.2, two symmetrical gate leaves are installed - the left section 14.1 and the right 14.2, which are metal sheets with slots made in them under the main burner tube of claim 5 and welded handles, so that both flaps abut from the bottom in the support-guide corner of clause 13.2 and, together with it, are fixed vertically by the guide angle of clause 13.1. Thus, each leaf receives one degree of freedom in the form of horizontal movement (in a plane adjacent to the facade of the temporary firebox) with a change in the area of the kindling window and a corresponding change in the flow of atmospheric air supplied into the temporary firebox.

During the heating process, the set temperature mode is maintained by adjusting the draft (total draft of the chimney and discharge in the chimney fumes) and the flow rate of the heating gas. The total gas flow to the battery and separately to the coke and machine sides is regulated by valves on a temporary gas pipeline. There are also valves of clause 15 for shutting off the gas supply to each burner separately. On all burners in the furnace of the battery on the machine and coke sides, the gas flow rate is regulated by installing interchangeable diaphragms in the flange connections of item 16 immediately before each _th azo _{p gr} eay etapv _■ 13

° _{C) (2888 -.} Burner _by oo og _p e _r m _p mV yv strand _at replaceable diaphragm can change the inner diameter of the gas supply pipe, which will provide the change in volume of gas supplied to the burner.

 Table 1 shows a specific example of a phased continuous heating of the refractory masonry in accordance with the claimed method.

 Table 1.

An example of a graph for warming up a coke oven battery

Stage Day from the Preset Set The heating consumption started to rise temperature, propane - temperature heating ° C butane per day, ° C heating stages, t

1 6 34 50

2 6 40

 3 6 46

 4 6 52

 5 6 58

 6 6 64

 7 6 70

 He is 8 6 76

 +

 9 6 82

10 6 88

_{32 (8866} ° С ₎ yy aao ea _r azoei etp _p zog _p evatpg _p in --- 14

1 ₆₆₂₀₂ ° C ₎ -

Stage Day from the Preset Set The heating consumption started to rise temperature, propane heating temperatures, ° C butane per day, ° C heating stages, t

1 1 6 94 100

12 6 100

13 6 106

14 6 1 12

15 6 1 18

16 6 124

17 6 130

18 6 136

19 6 142

20 6 148

21 6 154

22 6 160

23 6 166

24 6 172 38

25 6 178

26 6 184

27 6 190

28 6 196

29 6 202

_{5 th (:} eyta _p and _{h p} e oa APG _p s _p Etap south _of Ba

fifteen

3 ₈₈₆₇₉ ° C _{) (} -

Stage Day from the Preset Set The heating consumption started to rise temperature, propane heating temperatures, ° C butane per day, ° C heating stages, t

30 6 208 455

31 6 214

32 6 220

33 9 229 and o 34 9 238

oo

GS 35 9 247

■ 1 ·

 (

O 36 12 259

R \ 1

 37 12 271

38 12 283

39 12 295

40 15 310

 "41 15 325

 42 15 340

43 15 355

44 15 370

45 18 388

46 18 406 300

47 18 424

48 21 445

49 21 466

50 21 487 o azg _r eva an _p

 16

° C _{) 0 i 115}

 Stage Day from the Preset Set The heating consumption started to rise temperature, propane heating temperatures, ° C butane per day, ° C heating stages, t

51 24 51 1

52 24 535

53 24 559

54 24 583

55 24 607

56 24 631

57 24 655

58 24 679

59 24 703 420

60 32 735

61 32 767

62 32 799

63 36 835

64 36 871th ι 65 65 48 919

 "OS

 About Γ ~

 66 48 967

67 48 1015

Total: 1363 As can be seen from the table, the method is characterized by the continuity of the process and a quite acceptable consumption of affordable and cheap heat carrier - liquefied propane-butane.

Industrial applicability

Thus, the claimed method can be implemented using fairly simple devices, which simplifies the method as a whole, ensures the continuity and uniformity of masonry heating in the absence of external furnaces for heating.

Claims

Claim 1. The method of heating the refractory masonry of a coke oven battery, comprising supplying heating gas to the chambers of coke ovens and heating in accordance with a predetermined temperature regime, characterized in that liquefied propane-butane is used as heating gas, which is first subjected to regasification in an evaporator-heat exchanger, then fed to the burners, each of which is equipped with a screen, and installed in the temporary internal furnace of each coke oven from the machine and coke sides of the battery, while through the kindling window, In the facade of the temporary internal firebox, a regulated air flow is supplied to the firebox in an amount necessary and sufficient for stable combustion of the propane-butane torch during the entire heating process, moreover, the amount of air supplied to the firebox is controlled using movable dampers installed in the kindling windows, and providing the possibility of changing the free area of the kindling window during the heating process, the specified temperature heating mode is supported by regulating the draft of the furnace and the flow rate of propane-butane supplied to the burners.  2. The method according to claim 1, characterized in that the heating is carried out for 65-70 days to a temperature of 1000 - 1050 ° C.  3. The method according to claim 1, characterized in that the rate of temperature rise during heating is in the period of the first 32 days 5.5-6.5 ° per day, in the period of 33 - 35 days 9 ° per day , in the period of 36th - 39th day 12 ° per day, in the period of 40th - 44th day 15 ° per day, in the period of 45th - 47th day 18 ° С, in the period of 48th - 50 days 21 ° a day, during the 51st - 59th days 24 ° C, in the 60s - 62nd days 32 °, in the period 63-64 days 36 ° per day and from at a speed of 48 ° per day until the output to the specified mode.