KR200474985Y1 - System for dry cleaning and dry removal - Google Patents

Abstract

This invention relates to a method for dry removal and dry cleaning of gas containing pollutants and dust as gas produced in a coal gasification system, incidental to the pig iron production system during iron production, or incidental to the iron production system during iron production, , And means for performing the method. In the process, before the start of the dust removal after the pre-separation step, and after the temperature of the gas stream has been adjusted to a temperature of 60 ° C or higher and below the temperature causing damage to the equipment performing the dust removal, And optionally an additive comprising an absorbent material is added into the gas stream. The additive cleans the gas stream and is removed from the gas stream with the solid particles that were present in the gas stream prior to addition of the additive at the time of removal of the dust.

Description

[0001] SYSTEM FOR DRY CLEANING AND DRY REMOVAL [0002]

The present invention relates to a process for the production of pig iron during the production of pig iron, in which the gas produced in the pig iron production unit, or the gas produced in the iron production unit during the production of iron, or the gas produced in the coal gasification plant, Processes for dry scrubbing and for dry scrubbing of dust from gases, and devices for carrying out such processes.

설비, FINEX

설비 및 용융 가스 화로(melter gasifier) 같은 선철 생산 유닛에서 선철을 생산하는 동안, 또는 MIDREX

설비, HYL

설비 및 COREX

/FINEX

배기 가스에 기초한 직접 환원(DR) 설비 같은 철 생산 유닛에서 철을 생산하는 동안, 많은 양의 가스가 생산된다. 이러한 가스들은 높은 비율로 미세 고체 입자가 포함된 많은 양의 먼지, 및 많은 양의 가스 오염물을 따라 이동한다. 비정상 상태 동작 동안, 다시 말하여, 선철 또는 철 생산 공정의 시작 또는 중단 같은 특수 동작 상황 동안, 또는 물질 기둥의 자발적인 미끄러짐 같은 자발적 공정 이상(anomalies) 동안, 유닛 내에서, 특히 가스 내에 높은 양의 먼지 및 오염물이 발생하며, 또한 가스 온도 내의 피크도 발생한다. 가스가 환경으로 방출되기 이전에, 또는 그들이 하류 처리에서 이용되기 이전에, 먼지는 분리되어야 하며, 가스는 오염물로부터 세정되어야 한다.Blast furnace, COREX

Equipment, FINEX

During the production of pig iron in pig iron production units such as equipment and melter gasifiers,

Equipment, HYL

Equipment and COREX

/ FINEX

During the production of iron in an iron production unit, such as a direct reduction (DR) facility based on exhaust gas, a large amount of gas is produced. These gases travel at high rates along with large amounts of dust containing fine solid particles, and large amounts of gas contaminants. During abnormal state operation, that is to say during special operating situations such as the start or stop of a pig iron or iron production process, or during spontaneous process anomalies such as spontaneous slippage of material columns, a high amount of dust And contaminants are generated, and a peak in the gas temperature is also generated. Before the gases are released into the environment, or before they are used in downstream processing, the dust must be separated and the gas must be cleaned from the contaminants.

설비 또는 FINEX

설비에서 선철의 생산 동안 생산되는 가스의 성질은 다음과 같다.
For example, the blast furnace COREX

Equipment or FINEX

The nature of the gas produced during the production of pig iron in the facility is as follows.

It is known to remove dirt and contaminants from the produced gas using wet treatment, but such treatment has the disadvantage of treating the slurry and wash water produced. Chinese Patent Application No. CN1818080 discloses a process for dry removal of dust from a gas stream derived from a blast furnace. In this process, dry dust removal is achieved using a filtering separator after dry pre-separation in the separation chamber in the gas stream. Off-gas under the acid dew point of the moisture present in the gas stream, for example during start or shutdown, or below the dew point of the water, or during the off-gas under the steady- In the case of gas temperatures, such treatments can stick to the filter material of the separator and form an obstruction, because the composite transported in the gas, such as moisture or organic compounds, condenses. This can result in significant pressure loss of the filter material and loss of filter operation, and may result in essentially exchanging the filter material associated with the operational failure time. If the device on which the dust removal is performed becomes unavailable due to this problem, the dust-containing gas must be vented to the environment without further cleaning. These circumvention conditions cause damage to the environment and are unacceptable in many industrialized countries. In order to reduce the risk of adherence or obstruction due to undershooting of the dew point due to gas temperature and its associated condensation, CN 1818080 discloses that the temperature of the pre- A heat exchanger is provided for raising and moving the temperature. A method of cleaning the off-gas of contaminants is not disclosed in CN1818080.

The present invention aims at a dry dust removal treatment for the off-gas produced during the production of pig iron, in which case the risk of adhesion and clogging in the filter for dust removal is reduced and at the same time the off- Cleaned from contaminants. Similarly, an apparatus for performing such processing will be provided.

The present invention is illustrated by way of example and with reference to the accompanying drawings schematically and described based on the following description.
Figure 1 shows an apparatus for performing an embodiment of the process according to the present invention.
Figure 2 shows a modified version of the device shown in Figure 1.

또는 FINEX

처리와 관련된 고로, 환원 샤프트 또는 용융 가스 화로이다. 고체거나 용해된 선철 또는 1차 철 생산물은 이러한 유닛 내에서 생산된다.This object is achieved by a process for the production of pig iron during the production of pig iron, the production of a gas produced in a pig iron production unit, or a gas produced in an iron production unit during production of iron, or a gas produced in a coal gasification plant, A process for the dry removal of gas from and from the gas for dry cleaning of the gas, comprising the same, dust and contaminants, characterized in that in said process, after the preliminary separation for the separation of coarse solid particles, So that during the dust removal, the solid particles present in the pre-separated gas stream are separated from the gas stream and the temperature of the gas stream is at least 60 ° C., preferably at least 100 ° C. , And the temperature at which damage is caused to the device performing the dust removal , The temperature of the gas stream is set prior to the removal of the dust. The process is characterized in that the additive comprising the reactants and, if appropriate, the adsorbent are added to the gas stream prior to the start of the dust removal. For example, the pig iron production unit is a COREX

Or FINEX

A blast furnace associated with the process, a reduction shaft or a melt gasifier. Solid or molten pig iron or primary iron products are produced in these units.

설비, HYL

설비, 혹은 COREX

또는 FINEX

배기 가스에 기초한 직접 환원 설비일 수 있다. 스펀지 철 또는 브리켓(briquetted) 철이 이러한 유닛 내에서 생산된다.For example, the iron production unit may be a MIDREX

Equipment, HYL

Equipment or COREX

Or FINEX

It may be a direct reduction facility based on exhaust gas. Sponge iron or briquetted iron is produced in these units.

During the optionally provided pre-separation, the coarse solid particles carried together in the gas stream may be separated, for example, be separated in a gravitational chamber (dust bag) or a cyclone. Here, it should be understood that coarse solid particles mean solid particles having a particle diameter larger than 10 占 퐉. Since the pre-separation effectively separates only the thick solid particle size to the lower limit specified above, the solid particles that fall below this lower limit are still present in the gas stream after the above-described pre-separation. The above solid particles containing fine dust particles of less than or equal to 2.5 μm and, if not pre-separation is not carried out, the thick solid particles are also removed from the gas stream to a dust concentration of less than 5 mg / Nm ³ during dust removal.

If pre-separation is performed, the temperature of the gas stream prior to dust removal is set according to one embodiment of the process according to the present invention after pre-separation.

 During the production of pig iron or iron, the temperature of the gas varies, for example depending on the process used, or in the non-steady state of the process, such as the collapse of the column of material in the reduction or melting shaft, ). ≪ / RTI >

또는 P84

(polyimide fibers) 같은 합성 섬유로 만들어지며 둥근 형태의 구조를 가지는 섬유(fabric) 필터, 금속 필터 또는 세라믹 필터 같은 필터링 장치 내에서 일어난다.Dust removal is done by fiberglass, Aramid

Or P84

such as fiber filters, metal filters or ceramic filters, made of synthetic fibers such as polyimide fibers and having a rounded structure.

To protect the device from which dust removal is carried out from condensation problems that cause adherence of the discrete filter masses during dust removal and to protect against temperature peaks in the gas stream prior to dust removal and after selective pre- The temperature of the gas stream is set such that the temperature of the gas stream from which the dust removal is done is above 60 DEG C, preferably above 100 DEG C, and below the temperature at which damage to the apparatus for performing dust removal is caused. In the case of a fiber filter, the temperature must be below 260 ° C, preferably below 200 ° C, because the fiber filter experiences heat-induced degradation of the fiber filter at a gas temperature above 260 ° C. In the case of a ceramic filter or a metal filter, it is possible to use a gas temperature up to 1000 deg.

The gas produced during the production of pig iron in the pig iron production unit or the gas produced during the production of iron in the iron production unit may be inter alia hydrogen sulphide, hydrogen chloride, hydrogen fluoride, heavy metals, organic contaminants, For example, dioxin / furan, polycyclic aromatics and other hydrocarbon compounds. These environmentally hazardous off-gas components must be removed to an economically reasonable extent before the off-gas is released to the environment.

According to the present invention, particulate additives, dried additives or additives in the form of suspensions in water can be added to the gas stream prior to the start of dust removal. The additive comprises a reactive agent and, if appropriate, an adsorbent. The reactants are selected to react with contaminants present in the off-gas from the pig iron production facility to form a particle product that can be removed from the gas stream by dust removal. The reactants used are, for example, CaCO ₃ , Ca (OH) ₂ , Mg (OH) ₂ or sodium bicarbonate or a mixture of two or more of these substances. The primary task of the reactants is to separate acidic contaminant components such as H ₂ S, HCl or HF.

로 알려진, 첨가제를 구비한 라임-탄소(lime-carbon) 혼합물일 수도 있다. 입자형 첨가제 또는 입자형 반응 생산물 또는 입자형의, 첨가제 구성 성분이 흡착성 있게 포함된 미립자는 먼지 제거 동안 다시 가스 스트림으로부터 제거될 수 있다. The additive may also include organic and / or inorganic absorbents such as hearth furnace coke (HOK), activated carbon / coke or fine abrasive zeolite. Contaminants present in the off-gas, such as heavy metals or organic contaminants, can be removed from the gas stream by absorption using an absorbent, wherein the contaminant produced by the absorption-the absorbent product contained is in particulate form, And thus can be removed from the gas stream during dust removal. Additives may also be used, for example,

Or a lime-carbon mixture with an additive, also known as " water-soluble " Particulate additive or particulate reaction product or particulate particulate in which the additive component is adsorbed can be removed from the gas stream again during dust removal.

The additive may also be injected into the gas stream in the form of a suspension in water, for example in a milk of lime. A gas temperature of suitably higher than 150 ° C is required for the additive in suspension form. If the additive is added in the gas stream in suspension form. The liquid evaporates in the hot gas stream so that the additive can be removed during dust removal as a dry additive in particulate form. This type of additive can be associated with the process step of setting the gas temperature, since gas cooling can also occur if the additive is added in suspension form.

The addition of additives according to the present invention has the advantage that contaminants present in the gas can be removed simultaneously with the removal of dust from the gas stream. Another advantage is that both the reactants and the adsorbent bind moisture present in the gas, thereby reducing the condensation of moisture from the gas stream. A further advantage is that the particulate product produced during the reaction with the additive or the reactive agent or during the adsorption action of the adsorbent is deposited on a filtering and separating dust removal device. The result is that the device is coated. On the other hand, the coating of the additive containing the separate filter cake contributes to the removal of the dust, since the gas stream must pass through it. On the other hand, it protects the filtering and separation equipment part of the dust removal device, since only the off-gas stream is affected when it passes through the coating. Since the organic gas content or moisture of the gas stream and / or the micro-adsorptive solid particles can be partly already separated in the filter cake, the risk of adherence or obstruction of the filtering and separation equipment part of the dust removal device can be reduced have. As a result, the protection of the equipment part achieved results in an increased service life.

The additive coating is removed periodically with the filter cake of dust formed during the dust removal process on the filtering and separation equipment part of the dust removal device; This removal is less expensive and less cumbersome than the removal of penetrating solid particles within the filtering and separation facility portion of the dust removal device.

According to one embodiment, the addition of the additive is performed according to loading of the contaminant-containing gas. In this context, the amount of contaminant is measured, the proper addition of the additive is triggered, and the appropriate addition of the additive is increased if the threshold value in the natural gas or cleaning gas predefined by the operator is exceeded. In this context, natural gas may be understood to mean gas prior to dry scrubbing, and cleaning gas may be understood to mean gas after dry scrubbing. It is desirable that it can take into account a single type of contaminant. According to a preferred embodiment, the form of the reactants in the additive is chosen on the basis of the contaminant to be considered. As a result, it is possible to add a reactant optimally suited to the contaminant in question. Thus, the cost of consuming the reactants can be minimized, and the solid particles separated during dust removal can be reduced in large amounts. This simplifies the appropriate additional applications.

If pre-separation is performed, according to one embodiment of the process according to the present invention, an additive is added to the gas stream before the start of dust removal after pre-separation. As a result, the removal of the additive from the gas stream prior to dust removal is avoided. If not, the period of time in which the additive remains in the gas stream is reduced compared to the separation during dust removal, and thus the cleaning capacity of the additive will be used in a lesser amount. Since only the additive is added to the gas stream after the pre-cleaning, the material obtained during the pre-separation does not include any additive. Due to the lack of additives, these materials are particularly well suited for use. Since the material does not include any additive, it is not necessary to consider any additive present in use. Illustratively, such utilization may be recirculation of the at least partial material into the process from which the gas to be cleaned is calculated. However, the material may be used in other processes.

If the gas to be cleaned is produced in a pig iron production unit during the production of pig iron or in an iron production unit during iron production, the material obtained during the pre-separation can be recycled back to the production of iron-containing dust, Valuable raw materials. If the gas to be cleaned is produced in a coal gasification plant, the material obtained during the pre-separation contains carbon-containing dust - for example, valuable raw materials that can be recycled back into the gas-gasification plant.

Preliminary separation has the advantage that less loading is achieved due to contact with the solid particles in the part of the installation where the gas flows after preliminary separation.

Accordingly, the process according to the present invention can be applied to the filtering and separation of the part of the dust removing device or the risk of the obstruction, especially in the operating state in the case of operation and interruption or operation interruption of the pig iron or iron production unit, So that dust removal can be performed under less disruption compared to the prior art. Thus, since dust removal and contaminant cleaning can be performed in this operating state, there is virtually no need to release dust and contaminant-containing gas through the bypass to the environment.

According to one embodiment, the additive comprises at least one of a reactant and an adsorbent; This is because additional components of additives that do not act as reactants or adsorbents reduce the achievable effect of additives per unit mass of additive.

The added particulate dry additive has a crystal size of 0.1 to 200 탆. The crystal size range ensures that the additive can be homogeneously distributed in the gas stream. A homogeneous distribution in the gas stream is difficult if an important part of the crystal size lies outside of this range, which will result in a low separation rate during dust removal. The smaller the crystal size of the additive, the larger its specific surface area. As the specific surface area increases, the reaction with the contaminants, the adsorption of the contaminants, and the binding of the moisture become possible, so that the treatment can be performed more efficiently.

However, the price of the additive increases as the crystal size becomes smaller, and thus the use of additives with a crystal size of less than 0.1 [mu] m is no longer economically rational. The off-gas from the pig iron production unit is generally at high pressure. The absolute pressure of the off-gas from the pig iron production unit is between 2 x 10 ⁵ Pa and 6 x 10 ⁵ Pa, i.e. between 2 and 5 bar. This pressure must be overcome during the addition of the additive to the gas stream. This preferably takes place using pneumatic pressure injection of the additive. Alternatively, the dry additive may be introduced using gravity dosing, where it can be used, for example, by using star feeders or double rotary locks to allow excess pressure to be sealed against the outside It must be ensured that it is sealed off. During addition of the additive to the gas stream it is essential to ensure that the additive is homogeneously distributed. This can be realized, for example, using a so-called static mixer (in the case of gravity administration) or an appropriate number of injection lances (in the case of pressure injection). The suspension may preferably be introduced using two fluid nozzles, wherein the liquid suspension is atomized using gas or vapor.

The solid particles separated during dust removal in the filtering and separating dust removal device are periodically removed from the devices. The separated solid particles also include an additive capable of absorbing contaminants or capable of binding moisture, which can still react with contaminants present in the off-gas.

Thus, according to one embodiment of the process according to the present invention, the partial amount of solid particles separated during dust removal as a filter cake is added to the gas stream prior to the start of dust removal when additional pre-cleaning is complete. Recirculation of the additive into the gas stream increases the achievable effect per unit of additive; This is because the reaction, absorption and moisture binding potentials that have not yet been utilized after the first addition of a significant amount of additive can be used after the renewed addition to the gas stream. Compared to the recirculation-free process, it is thereby possible to achieve the same effect with less fresh additives, thereby allowing a considerable reduction in the amount of filter cake to be automatically removed. Because of the pressure of the off-gas, the addition is preferably carried out using pneumatic pressure injection, but may be carried out using, for example, gravity dosing.

및 광석-함유 먼지 같은 탄소 캐리어(carriers) 및 철-함유 먼지를 포함한다. 선철의 생산 또는 철의 생산 또는 석탄 가스화에서 이러한 물질을 이용하기 위해, 본 고안에 따른 공정의 유익한 실시예에 따르면, 필터 케이크로서 예비 분리 및/또는 먼지 제거 동안 분리된 적어도 부분적인 양의 고체 입자는 선철의 생산을 위한 또는 철의 생산을 위한 또는 석탄 가스화 설비에서 생산되는 가스를 위한 시작 물질로서 이용된다. 이는 그것의 경제적 생존 능력을 향상시키며 처분하는 경우보다 더 단순한 방법으로 분리된 고체 입자를 활용하게 한다. 그러나, 일례로, 위와 같은 물질은, 스틸 생산 공정(컨버터, 전기로)에서 또는 소결 공정에서 예비 처리 단계 이후에 이용될 수 있다.The solid particles separated by the filtering and separating dust remover are also carbon dust, hearth coke, Sorbalit

And carbon-containing carriers such as ore-containing dust and iron-containing dust. According to an advantageous embodiment of the process according to the present invention, in order to utilize these materials in the production of pig iron or in the production of iron or coal gasification, at least a partial amount of solid particles separated during pre- separation and / Is used as a starting material for the production of pig iron or for the production of iron or for gas produced in coal gasification plants. This improves its economic viability and makes it possible to utilize the separated solid particles in a simpler way than when disposing. However, for example, such materials may be used in steel production processes (converters, furnaces) or after the pretreatment step in the sintering process.

According to one embodiment of the process according to the present invention, the temperature of the gas stream from which dust is removed is set using an evaporative cooler. This has the advantage that the temperature can be adjusted in a stable manner even at a desired temperature for a relatively long period of time.

According to another embodiment of the process according to the present invention, the temperature is set using a plate heat exchanger. This has the advantage that there is no additional injection of water to be provided and the average gas temperature or the sensible heat of the gas is higher. For example, this increases the energy efficiency for subsequent use in the gas expansion turbine as compared to the temperature setting with the evaporative cooler. In this case, there are generally two exemplary variations. One of them is guided via a heat accumulator only when the gas exceeds the maximum operating temperature of the apparatus for performing dust removal (for example, 260 DEG C), and when the temperature is undershooted, And the other is that the two plate heat exchangers are connected in parallel. If the discharge temperature of one regenerator exceeds the maximum operating temperature, it is switched to another regenerator, for example ambient air, in the meantime, to a further cooled hot regenerator.

Coal gasification plants, which can be designed as fixed-bed gasifiers or entrained-flow vaporizers, can be used in their nature, particularly from pig iron and iron production units for dust loading and pollutant loading Gas compared to that of the gas. Gas from the coal gasification plant is used as the reducing gas, among others, during the production of pig iron or iron. According to one embodiment of the process according to the present invention, the gas from which the dry dust removal and the dry cleaning are performed originates from a coal gasification plant.

The process according to the present invention comprises a pellet production unit, or iron production unit, a feed line for delivering a gas stream from a coal gasification plant, wherein a pre-separation device is located in the feed line, Wherein the primary gas line is connected to the dust removal devices via a connection line, and wherein the device for setting the temperature of the gas stream comprises: Gas line or an apparatus located upstream of the dust removal device in the primary gas line.

The apparatus includes an apparatus for adding an additive in the primary gas line, and the apparatus for adding the additive is located between the branch point and the first connection line when viewed from the branch point.

및 FINEX

공정과 관련된 고로, 환원 샤프트 또는 용융 가스 화로일 수 있다.As an example, the off-gas, pig iron production unit, which is to be freed from dust and cleaned,

And FINEX

A blast furnace associated with the process, a reduction shaft, or a melt gasification process.

설비, HYL

설비, 혹은 COREX

또는 FINEX

배기 가스에 기초한 직접 환원 설비일 수 있다.For example, the iron production unit may be a MIDREX

Equipment, HYL

Equipment or COREX

Or FINEX

It may be a direct reduction facility based on exhaust gas.

A feed line for delivering a gas stream from a pig iron production unit or an iron production unit is connected to a pig iron production unit or an iron production unit.

또는 정전 필터를 포함한다. 이러한 장치들은 효율적으로 굵은 고체 입자를 가스 스트림으로부터 분리하는데 이용될 수 있다. 먼지 제거 장치는, 예를 들어, 직물 섬유, 세라믹 또는 금속 섬유의 필터 백을 구비한 둥근 필터를 포함한다. 이러한 장치들은 10μm 보다 작은 매우 미세한 고체 입자를 가스 스트림으로부터 효율적으로 분리하는데 이용될 수 있다. 이러한 형태의 예비 분리 장치 및 먼지 제거 장치는 먼지가 제거되는 가스의 압력에서 작동할 수 있다.The pre-separator may be, for example, a gravity settling chamber, a cyclone, a Hurriclon

Or an electrostatic filter. These devices can be used to efficiently separate thick solid particles from the gas stream. The dust removal device includes, for example, a round filter with a filter bag of fabric fiber, ceramic or metal fiber. These devices can be used to efficiently separate very fine solid particles smaller than 10 mu m from the gas stream. This type of pre-separation device and dust removal device can operate at the pressure of the gas from which the dust is removed.

According to one embodiment of the apparatus according to the present invention, a device for setting the temperature of the gas stream is located between the pre-separation device and the dust removal device.

According to one embodiment of the apparatus according to the present invention, the apparatus for adding particulate dry additive is a device for pneumatic pressure injection. According to another embodiment of the apparatus according to the present invention, the apparatus for adding the additive is a device for gravity administration.

According to one embodiment of the apparatus according to the present invention, the dust removing apparatus includes an apparatus for removing separated solid particles.

According to one embodiment of the device according to the present invention, the pre-separation device comprises an apparatus for removing solid particles separated from the pre-separation device.

According to a further embodiment of the device according to the present invention, the solid particle line is a solid particle line which, when viewed from the branch point in the bypass line and the primary gas line, or when viewed in the direction of flow of the gas stream, Is derived from the device and proceeds to the primary gas line upstream of the first connection line. The advancing point is advantageously provided with a device for pneumatic pressure injection, by means of which solid particles can be introduced into the primary gas line against the pressure of the gas stream.

According to a further embodiment of the device according to the present invention, an additional line is derived from the device for removing the separated solid particles and / or from the device for removing the separated solid particles from the pre-separation device, We move on to a device that adds material to the production unit.

According to a further embodiment of the device according to the present invention, the device for setting the temperature of the gas stream is an evaporative cooler.

According to another embodiment of the apparatus according to the present invention, the apparatus for setting the temperature of the gas stream comprises a plate heat exchanger or other type of heat exchanger such as a tube bundle, an enhanced cold wind chiller, and a Ljungstrom heat exchanger.

According to a further embodiment of the device according to the present invention, the device for setting the temperature of the gas stream comprises a burner. The burner is capable of rapidly increasing the temperature of the gas stream above the lower limit of 60 占 폚, usually by simple equipment and in a controlled and easy manner. The fuel supplied to the burner is a combustible gas or a combustible gas mixture. It is desirable to use at least a portion of dry dedusted and dry cleaned gases obtained in the process according to the present invention as fuel for the burner.

According to the present invention, the feed line directs the gas stream from the coal gasification plant connected to the feed line.

The invention also relates to the use of energy present in the gas, for example in the dust removal and cleaning process, for the production of electricity in the downstream turbine, for example in the use of energy present in the expanded turbine or gas components It also achieves the objective of simplifying - for example, in chemical processes.

This use is simplified by the use of cleaning and dust removal according to the present invention because the equipment parts employed for this use are subject to attack by, for example, solid particles and contaminants which are rubbing and corrosive Because it is exposed to a small extent.

It is essential to set the temperature of the gas stream if it is heated - for example by means of a burner - it is necessary to at least partly recover the thermal energy supplied to the process in the use of the thermal energy of the downstream gas of dust removal and cleaning ) There is a profit.

For example, the top gas has a calorific value of about 1.4 kJ / Nm ³ K - a heating of about 500 000 Nm ³ / h requires a power of about 200 kW / K. In order to heat from 60 to 100 占 폚, a firepower of 200 * 40 = about 8 MW is required, which must be applied, for example, by a burner or heat exchanger. Its about 10 MW can be recovered using a TRT gas expansion turbine.

Similarly, the present invention achieves the objective of making solids present in the available gas and other materials carried along in the gas, since the substances obtained during pre-separation, dust removal and cleaning can be obtained separately from each other to be.

1 feeds a gas stream of gas produced in a pig iron production unit (not shown) to which the feed line 1 is connected, during the production of pig iron. A pre-separation device 2, in this case a cyclone, is located in the feed line 1. The coarse solid particles separated during the preliminary separation, having a crystal size of 10-200 μm, can be removed from the cyclone, which is illustrated by the arrows derived from the cyclone. The material removed from the cyclone does not contain any additive. It contains iron-containing dust-valuable raw materials which are particularly suited for being introduced into iron production units (not shown) by the absence of additives. Since the material does not contain any additive, no additive is introduced into the pig iron production unit if such introduction occurs. The feed line 1 is divided into a bypass line 4 and a primary gas line 6 leading from the branch point 3 to the chimney 5. The primary gas line 6 is connected to three connection lines 7, 8, 9 leading to the respective dust removal devices 10, 11, 12. The pre-separated gas stream is delivered to the dust removers 10, 11 and 12 through the primary gas line 6 and the connecting lines 7, 8 and 9. The apparatus for setting the temperature of the gas stream delivered out of the preliminary separator is characterized in that the plate heat exchanger (21a, 21b) apparatus connected in parallel in this case comprises a preliminary separator (2) in the primary gas line Is located between the branch points (3). If the discharge temperature of one of the plate heat exchangers exceeds the maximum allowable value of the gas temperature for the dust remover, it may be possible to switch to another plate heat exchanger, for example a hot plate heat exchanger, . An additional device for setting the temperature of the gas stream delivered to the outside of the pre-separation device is the evaporation cooler 13, in which the gas stream is treated with water and / or additional suspension, Is located between the device (2) and the dust remover (10, 11, 12). Moreover, an apparatus 14 for adding particulate dry solid additives, in this case an apparatus for pneumatic pressure injection, is located in the primary gas line 6. The device is located downstream of the plate heat exchanger and upstream of the evaporative cooler. The addition of the additive is coded by the arrow. The dust removing apparatuses 10, 11, 12 include apparatuses 15, 16, 17 for removing separated solid particles. Solid particles separated during dust removal are added into the gas stream via the solid particle line 18 and the solid particle line 18 is introduced into the gas stream as shown in the flow direction from the branch point 3, Derived from the device and into the primary gas line (6) upstream of the first gas line (7). The addition occurs using an apparatus for pneumatic pressure injection (not shown here).

The gas produced in the iron production unit during the production of the gas or iron produced in the pig iron production unit during the production of pig iron and which is cleaned and exhausted in accordance with the present invention can be used in the downstream process of dust removal, Can be used thermally in fine coal dry systems, steam power plants or gas and steam power plants. It can also be used as a reducing gas in the internal process during the production of pig iron or iron, for example after a gas treatment by CO ₂ modification or CO ₂ removal with natural gas, and is recirculated back into the process for the production of pig iron or iron . In the embodiment of the present invention shown in the figures, the exhausted and cleaned gas is used in the downstream process. The off-gas with dust removal and at a pressure of 2-6 x 10 ⁵ Pa, i.e. 2 to 6 bar, is supplied to the gas expansion turbine (TRT) 20 via an exhaust line 19 leading to all the dust removal devices ). In the gas expansion turbine, the pressure energy of the off-gas is used to produce electricity. The gas stream is directed to the dust removal device only in the event of operational disruption through bypass line (5).

Fig. 2 shows the device shown in Fig. 1 with the following differences when compared with Fig. There is no evaporative cooler. An apparatus 22 for removing solid particles separated from the pre-separation apparatus is shown. For clarity, FIG. 2 shows the point at which an additional line, derived from the device 22 for removing solid particles separated from the pre-separation device, leads from the point where the gas stream is derived to the device for the additive material of the pig iron production unit. Did not do it. As shown in the flow direction of the gas stream, there is a burner 23 in the feed line 1 as part of the apparatus for setting the temperature of the gas stream, upstream of the plate heat exchangers 21a and 21b. For energy use and for conversion to electric power, the thermal energy supplied by the burner is used to some extent within the downstream unit to utilize the thermal energy of the gas expansion turbine, cleaned and exhausted gas. This makes the process more economical.

1 supply line
2 pre-separation device
Third quarter branch
4 bypass line
5 chimneys
6 Primary gas line
7, 8, 9 connection lines
10, 11, 12 Dust removal device
13 Device for setting the temperature of the gas stream
14 Apparatus for adding additives
15, 16, 17 Apparatus for removing separated solid particles
18 solid particle line
19 Exhaust line
20 Gas Expansion Turbine (TRT)
21a, 21b Plate type heat exchanger
22 Device for removing solid particles separated from pre-separation device
23 burner

Claims (17)

For dry cleaning of the dust-containing and contaminant-containing gas produced in the pig iron production unit during pig iron production or produced in the iron production unit during iron production, and for dry removal of dust from the gas, A system for removal, comprising:
1. A feed line (1) for delivering a gas stream from a pig iron production unit or an iron production unit, wherein a preliminary separation device (2) is located in the feed line (1) (1) which branches off to bypass line (4) and primary gas line (6);
(10, 11, 12), said primary gas line (6) being connected to said dust removers (10, 11, 12) via connecting lines (7, 8, 9) A dust removing device (10, 11, 12); And
An apparatus for setting the temperature of the gas stream upstream of the dust removal apparatus (10, 11, 12) in the primary gas line (6) or the supply line (1); / RTI >
A system for dry cleaning and dry removal,
Wherein the additive addition device 14 includes an additive addition device 14 for adding an additive in the primary gas line, and the additive addition device 14 includes a branch point 3 and a first connection line 7). ≪ RTI ID = 0.0 >
Systems for dry cleaning and dry removal.
The method according to claim 1,
Characterized in that the additive addition device (14) is a pneumatic pressure injection device.
Systems for dry cleaning and dry removal.
The method according to claim 1,
Characterized in that the additive addition device (14) is a gravity dosing device.
Systems for dry cleaning and dry removal.
4. The method according to any one of claims 1 to 3,
The dust removing device (10, 11, 12) comprises a device (15, 16, 17) for removing solid particles separated therefrom.
Systems for dry cleaning and dry removal.
4. The method according to any one of claims 1 to 3,
Characterized in that the pre-separation device (2) comprises an apparatus (22) for removing solid particles separated from the pre-
Systems for dry cleaning and dry removal.
6. The method of claim 5,
From the branch point (3), a solid particle line (18) is derived from the device (15, 16, 17) for removing the separated solid particles,
Characterized in that the solid particle line (18) is introduced into the primary gas line (6) upstream of the first connection line (7)
Systems for dry cleaning and dry removal.
The method according to claim 6,
An additional line is derived from one or both of the apparatus (15, 16, 17) for removing the separated solid particles and the apparatus (22) for removing solid particles separated from the pre-
Characterized in that the additional line leads to a device for adding material to the pig iron production unit or the iron production unit.
Systems for dry cleaning and dry removal.
The method according to claim 1,
Characterized in that the device for setting the temperature of the gas stream comprises one or both of an evaporative cooler (13) and a plate heat exchanger (21a, 21b)
Systems for dry cleaning and dry removal.
The method according to claim 1,
Characterized in that the device for setting the temperature of the gas stream comprises a burner (23)
Systems for dry cleaning and dry removal.
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