[0001] The invention relates to a method and apparatus for burning hydrocarbons or other
combustible liquids and gases, as well as to the manufacture and use of such an apparatus.
Background
[0002] Thermal combustion in the production of energy always results in nitrogen oxides
(NOx), because at a high temperature (>1000°C) the atmospheric nitrogen or organic
nitrogen contained in fuel reacts with combustion air or oxygen contained in fuel.
The higher the temperature and the longer the burn time, the more NOx emissions are
produced. Another problem is that thermal combustion is never complete, but the flue
gas is always left with unburned hydrocarbons (VOC), or carbon monoxide (CO) as a
result of incomplete combustion. The resulting amount of these is the higher, the
lower is the temperature and the shorter is the burn time, i.e. the emissions produced
as a result of reducing (NOx) and oxidizing (HC and CO) reactions require conflicting
conditions. Authorities have started to introduce stricter emission regulations based
i.a. on BAT (Best Available Technology) resolutions in Europe and BAC (Best Available
Control) standards in the USA.
[0003] The main topic in public debate has recently focused on carbon dioxide (CO
2) emissions because of their greenhouse effects. What has been overlooked to some
extent is that hydrocarbon emissions are greenhouse gases an order of magnitude more
powerful than CO
2. Likewise, nitrogen oxides are greenhouse gases and causes of acid rains and, jointly
with VOC gases, are sources of tropospheric ozone, which is highly detrimental to
plants and people. For these reasons, the NOx and VOC emission regulations are also
being tightened simultaneously with CO
2 emissions. The elimination of nitrogen oxide emissions is expensive as it calls for
secondary methods which generally impair efficiency (increase CO
2 emissions) and also increase investment and operating costs. One of the most effective
currently employed secondary NOx removal measures is the SCR (Selective Catalytic
Reduction) catalytic converter and a selective reducer (ammonia or urea) compatible
therewith. The removal of VOC and CO emissions from flue gas is easier. All that is
needed for those is an oxidation catalyst. In addition, all above-mentioned compounds
require a temperature higher than 250°C and the subsequent recovery of heat. The cleanup
of flue gases is expensive in terms of both investment and operating costs. An alternative
solution is to oxidize organic fuels so as not to produce the above-mentioned emissions
practically at all. This is possible with catalytic combustion and the combination
of thermal and catalytic combustion as the gas temperature can be maintained at a
sufficiently low level the reaction time very short as compared to thermal combustion.
Another possibility is to burn gaseous or liquid fuel thermally with a stoichiometric
air-fuel ratio. The NOx produced in thermal combustion can be reduced in a catalytic
converter subsequent to the thermal combustion.
[0004] Carbon dioxide is always produced when burning organic compounds. One possibility
of exploiting carbon dioxide generated in burning are greenhouses, which need carbon
dioxide not only for heating energy but also both for replacing the carbon dioxide
consumed in photosynthesis and for fertilizing plants. The double - triple excess
of carbon dioxide with respect to what is airborne (about 380 mg/Nm
3) may expedite growth by as much as 40%.
[0005] Greenhouses make up a good target for reducing CO
2 emissions, particularly if the energy is produced with an emission-free biofuel.
In this case, the greenhouses would function as carbon sinks. Catalytic combustion,
alone or jointly with thermal combustion, is particularly well applicable to the production
of energy for greenhouses as plants tolerate neither nitrogen oxides nor ethylene.
With regard to these emissions as well, the plants require about a hundred times cleaner
air than people.
[0006] The NOx's and VOC's generated in the production of energy needed for industry, traffic
and residential heating are a major problem. Together with sunlight, they produce
tropospheric ozones harmful for plants and people. Since February 1, 2012, NOx emissions
are limited by Californian BAC standards to the level of about 15 mg/Nm
3 (1,4-3 MW facilities). Larger facilities are required to have lower values of 5 mg/Nm
3 for NOx and 20 mg/Nm
3 for VOC and CO emissions. However, the standards vary from state to state. These
values are not reachable by thermal combustion alone. Yet, all these limit values
can be achieved with catalytic combustion or with a new combination of catalytic and
thermal combustion without a subsequent treatment of flue gas.
Description of the invention
[0007] What has been invented now is a method and apparatus for burning hydrocarbons or
other combustible gases and liquids, whereby the combustion can be performed in a
particularly effective manner. The invention relates also to a method for the manufacture
and use of such an apparatus.
[0008] The method and apparatus of the invention are presented in independent claims. In
addition, a few preferred embodiments of the invention are presented in dependent
claims.
[0009] An apparatus APP of the invention has been provided with or arranged to comprise
at least one inlet for a liquid and/or gaseous fuel and air and at least one outlet
for gases for removing the gases generated in the apparatus, as well as at least one
measurement and adjustment unit for adjusting the amount of fuel and air, and that
the apparatus APP has been provided with at least one pre-combustion zone for the
partial combustion of gases, and that the apparatus comprises at least one post-combustion
zone for the combustion of gases generated in pre-combustion, for the reduction of
NOx's produced in pre-combustion, and/or for the oxidation of hydrocarbon and carbon
monoxide emissions.
[0010] According to one object of the invention, at least one of the pre-combustion zones
and/or the post-combustion zones is a catalytic zone.
[0011] According to one object of the invention, the apparatus APP is provided with at least
one catalytic zone. According to one object of the invention, the apparatus APP is
provided with at least one thermal zone. According to one object of the invention,
the apparatus APP is provided with at least one catalytic pre-combustion zone and
at least one thermal post-combustion zone. According to one object of the invention,
the apparatus APP is provided with at least one catalytic pre-combustion zone and
at least one catalytic post-combustion zone, According to one object of the invention,
the apparatus APP is provided with at least one thermal pre-combustion zone and at
least one catalytic post-combustion zone. These are beneficial in certain embodiments
of the invention and contribute to improve combustion performance. According to one
object of the invention, the apparatus APP is provided with at least one heat exchanger
HE for the transfer of heat generated in pre-combustion and/or post-combustion. This
gives both economic and technical advantage.
[0012] The method according to the invention comprises respectively at least the following
operations:
- the partial pre-combustion of fuel in at least one pre-combustion zone, such that
the supplied fuel is burned only partially,
- the post-combustion of pre-combustion-generated gases in at least one post-combustion
zone for burning the pre-combustion-generated gases, for the reduction of pre-combustion-generated
NOx's, and/or for the oxidation of hydrocarbon and carbon monoxide emissions.
[0013] The apparatus and method can be implemented in one or more configurations. Hence,
the apparatus can have its components located in a single assembly or separated from
each other by one or more other intervening components or devices. Respectively, operations
can also be carried out in a single sequence or can be at least partially distinguished
from each other by one or more other intervening operations. These can also be integrated
for larger entities.
[0014] The apparatus and method can be used in the combustion of e.g. natural gas, biogas,
bioethanol, propane, methanol, ethanol, turpentine, butane, pentane, carbon monoxide,
hydrogen, light fuel oil, oil-water emulsion and/or any mixtures thereof.
[0015] According to one object of the invention, the measurement and adjustment unit C is
provided with or arranged to comprise at least one Lambda sensor for measuring the
oxidation/reduction potential of a flue gas. The inlet of fuel FUE and air AIR into
the apparatus APP can be adapted to occur within the Lambda range of 0,5-1,5.
[0016] According to one object of the invention, the combustion temperature is within the
range of 400-800 °C. Thus, there will preferably be no substantial NOx emissions.
[0017] If gases have high content of CO, catalytic zone can be selected so that temperature
is low, even 200 °C or lower. This significant adds lifetime of catalyst. Then proper
temperature can be e.g. 100 °C or more lower than normally. It is thus also in some
cases advantageous to have high content of CO in pre-treatment gas and burn it thereafter
in catalytic zone.
[0018] According to one object of the invention, the monitoring of NOx emissions is carried
out by using a NOx sensor, which is preferably useful for controlling the air-fuel
ratio as well.
[0019] According to one object of the invention, the monitoring of CO emissions is carried
out by using a CO-sensor, which is preferably useful for controlling the air-fuel
ratio as well.
[0020] The apparatus according to one object of the invention comprises either one thermal
burner with a liquid or gaseous fuel inlet and at least one catalytic converter for
the catalytic combustion of gases and for the reduction of NOx's generated in thermal
combustion and for the oxidation of hydrocarbon and carbon monoxide emissions. Since
reduction in the process of burning combustible gases necessitates a stoichiometric
air-fuel ratio, the apparatus is therefore further provided with at least one Lambda
sensor carrying out a measurement for the oxidation/reduction potential of a flue
gas, and provided with an air/fuel ratio adjustment system. The monitoring of NOx
emissions can be carried out by using a NOx sensor, which can also be used for controlling
the air-fuel ratio.
[0021] According to one object of the invention, at least one of the pre-combustion zones
and/or the post-combustion zones is a catalytic zone, which has activated portions
and non-activated portions for only the partial combustion of fuel and for adjusting
the temperature of combustion.
[0022] Thermal combustion in a pre-combustion process can be replaced by one or more catalytic
converters, of which the first, and possibly also the second catalytic converter is
only partially catalytically coated. According to one object of the invention the
catalytic converter honeycomb is provided with activated and non-activated channels
side by side. In this case, the reactions take place in the activated channel with
a "cold" unreacted gas proceeding in the adjacent channel. This enables cooling of
the high temperature created in the activated channel, since reactions in a catalytic
converter occur much more rapidly than thermal combustion. Hence the production of
heat can be distributed over several stages. Such a partially coated catalytic converter
can be preferably constructed from a metal foil by coating just one side of the foil
or by placing an uncoated foil to serve as every other foil. Partial combustion can
also be carried out by leaving a larger opening in the middle of the honeycomb or
a gap on the outer periphery. The alternatives are plausible in various combinations.
[0023] Catalytic combustion can be carried out with very lean mixtures, which is why the
boiler of the invention is able to burn simultaneously several fuels, comprising VOC
emissions. The supply of air and fuel for the burner can be controlled with temperatures
subsequent to catalytic converters.
[0024] One aspect with burners of the above type is that such burners can be constructed
as part of a boiler, which is preferably a tubular heat exchanger so as to enable
catalytic converters to be disposed at fixed intervals inside the pipes with water
or other liquid flowing outside the pipes. The idea here is that the production of
heat is distributed over several stages. Hence, the gas has time to cool prior to
the next catalytic converter with heat transferring to liquid. Thereby, the catalytic
converter can be kept from overheating and the gas can be kept hot over a longer distance.
The catalytic converter's channels are sufficiently small to eliminate the possibility
of thermal combustion. The combustion occurs in the form of intense oxidation taking
place on catalyst surfaces without a flame. Upon emerging from the catalytic converter,
the gas ignites immediately to burn thermally.
[0025] According to one object of the invention, the apparatus comprises at least one thermal
pre-treatment zone in fire-tube(s) in the fire-tube boiler and at least one catalytic
combustion zone as a post-treatment installed in smoke-tube(s) in the fire-tube boiler.
Fire-tube boiler can be e.g. one-way, two-way, three-way or four-way boiler. These
embodiments gives essential advantage because it gives very efficient way to control
both pre-combustion and post-combustion burning. It is also now possible to optimize
place of post-combustion catalytic zone in very advantageously. Catalytic zone can
be fixed case by case so that conditions for catalytic burning are optimal even in
varying temperatures and boiler loads. Place can be fixed by measuring or e.g. by
CFD (computational fluid dynamics). Term "fire-tube boiler" is to be understood in
this application also e.g. as shell boiler and water tube boiler. Term "fire-tube"
is to be understood in this application also e.g. as furnace, combustion chamber,
flame tube, first-pass, fire-box. Term "smoke-tube" is to be understood in this application
also e.g. as second pass, convection part, tube(s).
[0026] Temperature in fire-tube is usually over 1000 °C and in smoke-tubes 1000 to 300 °C.
Catalytic zone (e.g. three-way catalytic) is usually fixed e.g. to two-way tubes,
where conditions for catalytic burning are optimal even in varying temperatures and
boiler loads. Place can be fixed by measuring or e.g. by CFD (computational fluid
dynamics). In an example in two-way boiler, where temperature in fire-tube is between
1000 to 1750 °C and temperature in smoke tubes was 1000 to 300 °C, three-way catalytic
was placed so that current temperature in catalytic zone was about 360 to 860 °C.
[0027] This burner and boiler combination can be constructed from a conventional pipe heat
exchanger. Heat transfer can be enhanced by inducing a swirl in the gas. This heat
transfer solution is useful for achieving a more effective heat transfer performance
despite the lower peak temperature. Enclosed is one example. Likewise, the boiler
and burner become smaller in size and lower in costs. There is no need for special
materials, and standard solutions such as heat exchangers can be applied.
[0028] Example: In a three-way catalytic converter take place simultaneously the following
main reactions:
HC+O2→ H2O+CO2
CO + 02 → CO2
HC + NOx → H2O + CO
2 + N2
CO + NOx → CO2 + N2
[0029] Temperature in the catalytic converter may rise to an extraordinary high level (in
excess of 1500°C). Therefore, the catalytic converter must be constructed by using
highly heat resistant steel grades such as 1.4767, 1.4828, Nicrofer 6025 HT etc. or
ceramic honeycomb cells. It is preferred that the catalytic converter be coated with
some platinum group metal and a porous coating. Ecocat Oy, among others, has developed
a catalytic converter capable of withstanding extraordinarily high temperatures, which
is applicable to this purpose. A preferred solution from the standpoint of a favorable
combustion result is a mixing metal-core catalytic converter.
[0030] With traditional thermal combustion, it is difficult to reach a NOx level of 50 mg/Nm
3. An attempt to minimize the NOx emission brings forth a hazard of increased hydrocarbon
and carbon monoxide emissions due to incomplete burning. An advantage in the present
invention is that the combustion process as a whole is very short, nor is a large
pre-chamber necessary for burning. The generation of nitrogen oxides increases exponentially
as temperature is rising and directly proportionally as a function of burn time. The
increase of oxygen amount decreases the formation of NOx's in proportion to the square
root of the content.
[0031] The burner has a low maintenance demand and catalytic converters of precious metals
have a long service life. The burner consists of a few components easy to disassemble
for maintenance.
[0032] Greenhouses would make an excellent target for this technology. In the process of
burning propane, the resulting amount of carbon dioxide is 3-times, and in the process
of burning natural gas, it is 2-times with respect to the consumption of fuel. It
is almost an optimal amount from the standpoint of fertilizing demand for CO
2. At present, the fertilization is primarily carried out with liquefied carbon dioxide,
which is mainly produced by a fermentation process, and then purified and liquefied
by cooling. This is in total contradiction with current environmental regulations.
Another problem is the warming-up and evaporation of CO
2 during storage.
[0033] The catalytic Ultra LowNox, NoVoc and NoCo burner is small in size and attractive
in costs. It enables even the strictest emission standards to be attained without
post-flue gas treatment. The elimination of final emission percentage is always the
most expensive phase.
[0034] The useful fuels comprise nearly all gaseous and several liquid fuels, such as natural
gas, biogas, bioethanol, propane, light fuel oil, oil/water emulsions, etc. The most
practical are low sulfur fuels and gases not containing halogens. Even the latter
can be used, but necessarily with a different catalytic converter and boiler materials.
The combustion of sulfur compounds results in the formation of sulfuric acid and the
combustion of chlorinated hydrocarbons results in hydrochloric acid.
[0035] The removal of nitrogen oxides unavoidably generated in thermal combustion is difficult
and expensive downstream of the boiler. What is most commonly needed is an SCR or
SNCR (Selective Catalytic Reduction or Selective Non Catalytic Reduction) catalytic
converter and a selective reducer ammonia or urea therefor. In addition to a high
acquisition price, there will be a perpetual acquisition expense for the reducer (ammonia
or urea), nor is the low NOx level of a catalytic NoNox burner always reachable. The
reduction of NOx's generated in thermal combustion and the oxidation of VOC and CO
emissions require a temperature higher than 250°C.
[0036] The combined thermal and catalytic burner fulfills the present and tightening future
NOx, VOC and CO emission standards without any exhaust gas after-treatment. The catalytic
burner is a solution less expensive than any of the reference technologies for the
elimination of NOx, HC and CO emissions in energy production.
[0037] The catalytic burner is capable of achieving such low level NOx and ethylene emissions
that enable the delivery of flue gases directly into a greenhouse for a CO
2 fertilizer and the use of combustion-generated energy for greenhouse heating. The
NOx and ethylene emission standard for greenhouses is about 100 times stricter than
the workplace air quality standard for people.
[0038] The catalytic burner is a solution less expensive than any of the reference technologies
for the elimination of NOx, HC and CO emissions in energy production.
[0039] It is preferred that the catalytic burner be provided with a mixing honeycomb or
some other structure, which enhances material transfer and intensifies oxidation (diffusion
of combustion gas molecules in the micropores of a catalytic converter) and at the
same time reduces the amount of emissions.
[0040] A few embodiments of the invention are further depicted in figs. 1-3:
- fig. 1 shows an apparatus, comprising two catalytic pre-treatment zones and thermal
combustion as a post-treatment
- fig. 2 shows an apparatus, comprising two catalytic pre-treatment zones and catalytic
combustion as a post-treatment
- Fig. 3 shows an apparatus, comprising one thermal pre-treatment zone and two catalytic
combustions as a post-treatment
- Fig. 4 shows an apparatus comprising one thermal pre-treatment zone in fire-tube and
catalytic combustions as a post-treatment installed in smoke-tubes in two-way fire-tube
boiler
- Fig. 5 shows an apparatus comprising one thermal pre-treatment zone in fire-flue and
catalytic combustions as a post-treatment installed in smoke-tubes in a three-way
fire-tube boiler
[0041] . The apparatuses APP of figs. 1-3 are provided with one inlet for a liquid or gaseous
fuel FUE and for air AIR and one outlet for gases for removing gases EXHG generated
in the apparatus APP, as well as with at least one measurement and adjustment unit
C for adjusting the amount of fuel FUE and air AIR. Further depicted in figs. 1-3
are optional extra mixers MIX. The apparatuses comprise the following operations:
- the partial pre-combustion of fuel FUE in at least one pre-combustion zone Cz11, Cz12,
Tz1, such that the supplied fuel is burned only partially,
- the post-combustion of pre-combustion-generated gases GAS1 in at least one post-combustion
zone Tz2, Cz21, Cz22 for burning the pre-combustion-generated gases, for the reduction
of pre-combustion-generated NOx's, and/or for the oxidation of hydrocarbon and carbon
monoxide emissions, the pre-combustion and/or post-combustion being carried out in
at least one catalytic zone Cz11, Cz12, Cz21, Cz22, which comprises activated channels
and non-activated zones for just partial combustion of the fuel and for adjusting
the combustion temperature. The apparatuses APP of figs. 1-3 are provided with a heat
exchanger HE for the transfer of heat generated in pre-combustion and/or in post-combustion.
[0042] In figs. 1 and 3, the pre-combustion or post-combustion is carried out in one thermal
zone Tz1, Tz2. In fig. 1, the pre-combustion is carried out in two catalytic pre-combustion
zones Cz11, Cz12 and the post-combustion is carried out in one thermal post-combustion
zone Tz2. In fig. 2, the pre-combustion is carried out in two catalytic pre-combustion
zones Cz11, Cz12 and the post-combustion is carried out in one catalytic post-combustion
zone Cz21. In fig. 3, the pre-combustion is carried out in one thermal pre-combustion
zone Tz1 and the post-combustion is carried out in two catalytic post-combustion zones
Cz21, Cz22.
[0043] In figs. 4 and 5 pre-combustion or post-combustion is carried out in one thermal
zone Tz1 in fire-tube FLU, such that the supplied fuel is burned only partially. Post-combustion
is carried out in catalytic zone(s) Cz21, Cz22 in smoke-tubes FTU for burning the
pre-combustion-generated gases, for the reduction of pre-combustion-generated NOx's,
and/or for the oxidation of hydrocarbon and carbon monoxide emissions. The apparatuses
APP of figs. 4 and 5 are provided with one inlet for a liquid or gaseous fuel FUE
and for air AIR and one outlet for gases for removing gases EXHG generated in the
apparatus APP, as well as with at least one measurement and adjustment unit C for
adjusting the amount of fuel FUE and air AIR. The apparatuses APP of figs. 4 and 5
are provided with a heat exchanger HE for the transfer of heat generated in pre-combustion
and in post-combustion.
1. A method for burning hydrocarbons or other combustible liquids and gases in an apparatus
(APP), which is provided with at least one inlet for a liquid or gaseous fuel (FUE)
and for air (AIR) and at least one outlet for gases for removing gases (EXHG) generated
in the apparatus (APP), as well as with at least one measurement and adjustment unit
(C) for adjusting the amount of fuel (FUE) and air (AIR),
characterized in that the method comprises at least the following operations:
- the partial pre-combustion of fuel (FUE) in at least one pre-combustion zone (Cz11,
Cz12, Tz1), such that the supplied fuel is burned only partially,
- the post-combustion of pre-combustion-generated gases (GAS1) in at least one post-combustion
zone (Cz21, Cz22, Tz2) for burning the pre-combustion-generated gases, for the reduction
of pre-combustion-generated NOx's, and/or for the oxidation of hydrocarbon and carbon
monoxide emissions.
2. An apparatus (APP) for burning hydrocarbons or other combustible liquids and gases,
characterized in that the apparatus (APP) has been provided with at least one inlet for a liquid and/or
gaseous fuel (FUE) and air (AIR) and at least one outlet (EXHG) for gases for removing
the gases (EXHG) generated in the apparatus (APP), as well as at least one measurement
and adjustment unit (C) for adjusting the amount of fuel (FUE) and air (AIR), and
that the apparatus (APP) has been provided with at least one pre-combustion zone (Cz11,
Cz12, Tz1) for the partial combustion of gases, and that the apparatus comprises at
least one post-combustion zone (Cz21, Cz22, Tz2) for the combustion of gases generated
in pre-combustion, for the reduction of NOx's produced in pre-combustion, and/or for
the oxidation of hydrocarbon and carbon monoxide emissions.
3. A method for manufacturing an apparatus (APP) suitable for burning hydrocarbons or
other combustible liquids and gases, characterized in that the apparatus (APP) provided with at least one inlet for a liquid and/or gaseous
fuel (FUE) and air (AIR) and at least one outlet (EXHG) for gases for removing the
gases (EXHG) generated in the apparatus (APP), as well as at least one measurement
and adjustment unit (C) for adjusting the amount of fuel (FUE) and air (AIR), and
that the apparatus (APP) is provided with at least one pre-combustion zone (Cz11,
Cz12, Tz1) for the partial combustion of gases, and that the apparatus is provided
with at least one post-combustion zone (Cz21, Cz22, Tz2) for the combustion of gases
generated in pre-combustion, for the reduction of NOx's produced in pre-combustion,
and/or for the oxidation of hydrocarbon and carbon monoxide emissions.
4. The use of the method and/or the apparatus according to claim 1 or 2, for burning
hydrocarbons or other combustible liquids and gases, in the combustion of natural
gas, biogas, bioethanol, propane, methanol, ethanol, turpentine, butane, pentane,
carbon monoxide, hydrogen, light fuel oil, oil/water emulsion and/or any mixtures
thereof.
5. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-4, characterized in that the pre-combustion and/or the post-combustion are/is carried out in at least one
catalytic zone (Cz11, Cz12, Cz21, Cz22).
6. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-5, characterized in that the pre-combustion and/or the post-combustion are/is carried out in at least one
thermal zone (Tz1, Tz2).
7. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-6, characterized in that the pre-combustion is carried out in at least one thermal pre-combustion zone (Tz1)
and the post-combustion is carried out in at least one catalytic post-combustion zone
(Cz21, Cz22).
8. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-7, characterized in that the pre-combustion is carried out in at least one catalytic pre-combustion zone (Cz11,
Cz12) and the post-combustion is carried out in at least one catalytic post-combustion
zone (Cz21, Cz22).
9. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-8, characterized in that the supply of fuel (FUE) and the supply of air (AIR) into the apparatus (APP) is
arranged to occur within the Lambda range of 0,5-1,5.
10. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to claim 9, characterized in that Lambda is >1,0 (lean mixture).
11. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to claim 9, characterized in that Lambda is <1,0 (rich mixture).
12. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to claim 9, characterized in Lambda is 0,99 to 1,01 (stoichiometric air-fuel ratio or near it).
13. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-12, characterized in that said apparatus (APP) comprise at least one of catalyst zone (Cz11, Cz12, Cz21, Cz22)
having three-way catalytic.
14. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-13, characterized in that pre-combustion is arranged in lowered temperature.
15. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-14, characterized in that the supply of fuel (FUE) and the supply of air (AIR) into the apparatus (APP) is
arranged by monitoring NOx emissions by using a NOx sensor.
16. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-15, characterized in that the apparatus (APP) has been provided with at least one heat exchanger (HE) for the
transfer of heat generated in pre-combustion and/or in post-combustion.
17. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claims
1-16, characterized in that the apparatus (APP) is fire-tube boiler comprising at least one thermal pre-treatment
zone (Tz1) in fire-tube(s) FFL and at least one catalytic combustion zone (Cz21, Cz22)
as a post-treatment installed in smoke-tube(s) FTU.
18. The method, the apparatus, the method for manufacturing an apparatus (APP) for burning
hydrocarbons or other combustible liquids and/or the use according to any of claim
17, characterized in that place of post-treatment catalyst(s) (Cz21, Cz22) is arranged according to the burning
temperature in smoke-tube(s) FTU and optimized operating temperature of said catalyst(s)
(Cz21, Cz22).