JP6899787B2 - Catalytic reactor blockage detection method, blockage elimination method, and catalytic reactor - Google Patents

Description

The present invention relates to an operating method for operating a catalytic reactor under suitable reaction conditions and an apparatus used therein, and more particularly to a method for detecting blockage of the catalytic reactor, a method for eliminating blockage, and a catalytic reactor.

In an externally heated catalytic reactor that supplies the reaction heat required for the catalytic reaction to the catalytic reactor by heating the catalytic reactor from the outside, in order to secure a sufficient heating area, a thin tube filled with a catalyst as a fixed bed is used. It is common practice to arrange a plurality of catalytic reactors in parallel in a heating furnace. The individual catalytic reactors installed in parallel are often connected to a common inflow collecting pipe and a common outflow collecting pipe. Patent Documents 1 and 2 describe an example of such a catalytic reactor.

In the operations described in Patent Documents 1 and 2, the raw material gas contains a hydrocarbon gas, the catalytic reaction is a steam reforming reaction, and the produced gas is a synthetic gas. When such an operation is performed, cork (solid carbon or hydrocarbon) is produced by a catalytic cracking reaction of hydrocarbon gas, which is a side reaction during the operation. Then, cork gradually accumulates in the catalyst layer (that is, the fixed bed) and hinders the aeration of gas in the catalyst layer. As the amount of cork deposited increases, a so-called blockage state may be reached in which the gas can hardly be aerated even if a differential pressure is finally applied between the inlet side and the outlet side of the catalytic reactor.

When a plurality of catalytic reactors are arranged in parallel, even if some of the catalytic reactors are blocked, the fluid can pass through the catalytic reactors that have not been blocked yet, so that it is a single catalytic reactor. A large pressure loss does not always occur between the inflow collecting pipe and the outflow collecting pipe as in the case of the blockage. However, in a catalytic reactor that is not closed yet and the flow is concentrated, the space velocity (= flow rate / catalyst volume) increases, so the raw material cannot be sufficiently reformed, and a large amount of raw material gas remains in the produced gas. It can cause so-called poor reaction. Therefore, when the catalytic reactor is blocked, it is necessary to promptly release the blocked state. As a means for releasing the blocked state during operation, for example, Patent Documents 1 and 2 disclose an elevating mechanism for the catalyst layer.

JP-A-2017-56375 Japanese Unexamined Patent Publication No. 2016-159264

The problem here is that, among the plurality of catalytic reactors, there has not been a simple method for detecting which catalytic reactor is clogged.

If the technique of releasing the blocked state is frequently used without detecting the blockage of the catalytic reactor, the blockage is certainly less likely to occur, but another problem arises. For example, when the catalyst layer elevating mechanism described in Patent Document 2 is used as a means for releasing the blocked state, the catalyst is damaged at a constant rate each time the catalyst layer is elevated. Therefore, if the catalyst layer is moved up and down too frequently, there arises a problem that the catalyst is easily damaged beyond the permissible range. Therefore, the means for releasing the blocked state should be applied only when the blocked state of the catalytic reactor is detected. Therefore, there is a need for a method of detecting blockages in individual catalytic reactors.

In a catalytic reactor consisting of a single catalytic reactor, when the catalytic reactor is blocked, the differential pressure between the inflow collecting pipe and the outflow collecting pipe increases. Therefore, the blockage can be easily detected by measuring the differential pressure. However, in a catalytic reactor in which a plurality of catalytic reactors are arranged in parallel, even if one of the catalytic reactors is blocked, the gas that cannot pass through the catalyst layer of the catalytic reaction is transferred to the other catalytic reactor. Easily detour. Therefore, the differential pressure between the entry side and the exit side of the closed catalyst layer does not change so much, and the flow rate in the closed catalyst reactor decreases. Therefore, it is difficult to detect the blockage of the catalytic reactor only by measuring the differential pressure.

Alternatively, a method of providing a flow meter for each catalytic reactor can function in principle by utilizing the fact that the flow rate decreases in the catalyst reactor in which the blockage occurs. For example, it is conceivable to provide an orifice for each catalytic reactor and calculate the flow velocity from the differential pressure before and after the orifice based on Bernui's principle. However, the flow velocity in the catalytic reactor is generally relatively small, about several tens of cm / s. Therefore, in this method, the differential pressure generated before and after the orifice is extremely small. For this reason, it is not economically realistic because the measurement error becomes large or it is necessary to arrange a large number of expensive precision differential pressure gauges.

It is also conceivable to provide a flow velocity detection probe capable of detecting a minute flow velocity, for example, a Karman vortex flow meter or a Koriori flow meter in each catalytic reactor. However, since all the catalytic reactors are arranged in a high-temperature heating furnace, the above-mentioned flow velocity detection probe is also required to have high heat resistance. Such an instrument is not practical because it is not commercially available, or if it is manufactured independently, it becomes an extremely expensive device.

Therefore, in the present invention, in a catalytic reactor composed of a plurality of catalytic reactors arranged in parallel in a heating furnace, it is inexpensive and easy to use individually without providing a flow rate or measuring means for each catalytic reactor. The purpose is to detect blockage in the catalytic reactor.

In order to solve the above problems, according to a certain viewpoint of the present invention, a non-compressible fluid which is a raw material fluid in a catalyst layer which is a fixed bed in a catalytic reactor arranged in parallel in a catalytic reactor. This is a method for detecting blockage of a catalytic reactor due to accumulation of by-products in the catalyst layer when reforming by reacting the above, and the catalytic reactors are arranged in parallel. Arranged catalytic reactors, inflow collecting tubes that are collecting tubes for supplying fluid to all catalytic reactors, and outflows that are collecting tubes for collecting fluids flowing out from all catalytic reactors and letting them flow downstream. Inside a heating furnace with adjustable furnace temperature, equipped with a collecting tube, a catalyst layer thermometer provided in each catalyst layer of all catalyst reactors, and an inflow thermometer that measures the inflow temperature, which is the fluid temperature of the inflow collecting tube. A fluid preheating device for preheating the fluid supplied to the inflow collecting pipe, and a fluid switching device for switching the fluid supplied to the inflow collecting pipe between the raw material fluid and the non-reactor fluid. And a flow meter that measures the flow rate passing through the inflow collecting pipe, and the blockage detection method of the catalytic reactor is to set the fluid switching device so that the non-reactive fluid passes through all the catalytic reactors. , inflow thermometer fluid preheater adjusted to exhibit a first inlet temperature T _in1, measured at a flow rate Q _T and each of the catalytic reactor of the catalyst layer thermometer inlet collector pipe when the catalyst The fluid preheater was adjusted so that the first operation of recording the layer temperatures T1 _{and i} and the inflow reactor showed a second inflow temperature _Tin2 different from the first inflow temperature _Tin1. The second operation of recording _{the catalyst layer temperatures T2 and i} measured by the catalyst layer thermometer of each catalyst reactor, and the second operation.
In the i-th catalytic reactor
β _i = hLX _i / (ρC _p )
h: Heat transmission coefficient L: Circumferential length of pipe ρ: Gas density Cp: Constant pressure specific heat of gas X _i : Length of pipe in i-th catalyst reactor Each catalyst uses _{β i defined by the equation. The third operation of calculating the flow rate Q i} in the reactor as a function of _{Tin 2} , _{Tin 1} , T _{1, i} , T _{2, i} , and β _i , and when the flow rate Q _i is smaller than a predetermined value, characterized in that it comprises a fourth operation and determines that the i-th catalytic reactor which corresponds to the flow rate Q _i are closed, the obstruction detection method of the catalytic reactor is provided.

Here, in the third operation,
Functions of T in ₂ , _{Tin 1} , T _{1, i} , T _{2, i} , and β _i,
Q _i = -β _i / Ln [(T _{2, i} −T _{1, i} ) / (T _in2- T _in1 )]
age,
β _i may be a fixed value.

としてもよい。 Further, the catalytic reaction device further includes a differential pressure measuring device for measuring the differential pressure between the inflow collecting pipe and the outflow collecting pipe.
In the third operation
η _i = ΔP / Q _i ²
_{ΔP: The resistance coefficient η i} defined by the equation of the differential pressure between the inflow collecting pipe and the outflow collecting pipe,
β _i = β _{0, i} · (η _i / η _{0, i} ) ^ai
β _{0, i} : Initial value of _{β i a i} : Model constant In addition to obtaining _{β i,}
The function of the flow rate _{Q i}

May be.

_{Further, the flow rate Q i} may be corrected so that the flow _{rate Q i} calculated in the third operation is integrated with the flow rate Q _{T for all the catalyst reactors.}

Further, the raw material fluid may contain hydrocarbons.

Further, the device in the heating furnace may further include a device for removing deposits in the catalyst layer for independently removing the deposits in the catalyst reactor for each catalyst reactor.

According to another aspect of the present invention, when the i-th catalyst reactor is determined to be clogged by the above-mentioned catalyst reactor blockage detection method, the i-th catalyst layer is clogged. A method for clearing a blockage of a catalyst reactor is provided, which comprises operating a deposit removing device in the catalyst layer of the catalyst reactor of the above.

According to another aspect of the present invention, in the catalyst layer which is a fixed bed in a plurality of catalyst reactors arranged in parallel, a non-compressible fluid which is a raw material fluid is reacted and reformed, and in the catalyst layer. A catalytic reactor that detects the blockage of catalytic reactors due to the accumulation of by-products in the reactor, and is a set of multiple catalytic reactors arranged in parallel to supply fluid to all catalytic reactors. Inflow collecting pipes, which are pipes, outflow collecting pipes, which are collecting pipes for collecting fluids flowing out from all catalytic reactors and flowing them downstream, and catalyst layer temperatures provided in the catalyst layers of all catalytic reactors. It has a meter and an inflow thermometer that measures the inflow temperature, which is the fluid temperature of the inflow collecting pipe. A fluid preheating device, a fluid switching device for switching the fluid supplied to the inflow collecting pipe between the raw material fluid and the non-reacting fluid, and a flow meter for measuring the flow rate passing through the inflow collecting pipe are provided. Furthermore, the fluid switching device is set so that the non-reactive fluid passes through all the catalytic reactors, and the fluid preheating device is adjusted so that _{the inflow thermometer shows the first inflow temperature Tin1.} first means for recording the flow rate Q _T and each of the catalytic reactor of the catalyst layer a catalyst layer temperatures T ₁ which is measured by a _{thermometer, i} of the inlet manifold pipe, the inflow thermometer first inlet temperature T _in1 The furnace temperature of the fluid preheater is adjusted so as to indicate _{the second inflow temperature Tin} 2 different from that of the _{above, and the catalyst layer temperatures T 2 and i} measured by the catalyst layer thermometer of each catalyst reactor at that time are set. A second means of recording and
In the i-th catalytic reactor
β _i = hLX _i / (ρC _p )
h: Heat transmission coefficient L: Circumferential length of pipe ρ: Gas density Cp: Constant pressure specific heat of gas X _i : Length of pipe in i-th catalyst reactor Each catalyst uses _{β i defined by the equation. A third means of calculating the flow rate Q i} in the reactor as a function of _{Tin 2} , _{Tin 1} , T _{1, i} , T _{2, i} , and β _i , and when the flow rate Q _i is smaller than a predetermined value. comprising the i-th catalytic reactor fourth determining is as that blockage of means corresponding to the flow rate Q _i, the blockage detection determination unit of the catalytic reactor for the execution, the catalytic reactor is provided, characterized in that To.

Here, the device in the heating furnace may further include a device for removing deposits in the catalyst layer for independently removing the deposits in the catalyst reactor for each catalyst reactor.

(Features of the present invention)
The feature of the present invention is a relatively easy measurement of a change in the temperature distribution of the catalyst reactor arranged in the heating reactor, specifically, a change in the temperature distribution of the catalyst layer installed in the catalyst reactor. It is possible to easily determine a specific catalytic reactor in which a blockage has occurred from a plurality of externally heated catalytic reactors arranged in parallel online. As described above, this determination has been difficult in the past.

In particular, the present inventor states that the change in drag coefficient (pressure loss coefficient) η caused by the deposition of by-products (for example, cork) in the catalytic reactor has a unique relationship with the heat transmission coefficient h in the catalytic reactor. We found a previously unknown finding. In the present invention, the flow rate in each catalytic reactor can be predicted more accurately based on such a novel finding and the above-mentioned temperature distribution change.

The most reliable method for determining blockage of a particular catalytic reactor is to directly measure the flow rate at each catalytic reactor. However, in the present invention, for example, a catalytic reactor arranged in a heating furnace having a high temperature of 700 ° C. or higher is targeted. There is no commercially available device for directly measuring a minute flow rate in such a catalytic reactor, and even if it is manufactured, it is extremely expensive, so it is not realistic. On the other hand, measuring the temperature of each catalyst layer can be easily realized simply by installing a commercially available sheath thermocouple for high temperature in the catalyst layer, and in fact, such temperature measurement is performed for operation management. Often. In the present invention, the flow rate in each catalyst reactor can be easily calculated by using the easily measurable temperature of each catalyst layer.

(Relationship between η and h)
Here, the correlation between the drag coefficient η in the catalytic reactor and the thermal transmissivity h will be described. The present inventor has found that there is a unique relationship between the drag coefficient η and the model constant β (specific details will be described later) that is proportional to the thermal transmission rate h. The present inventor _{investigated the relationship between η / η 0} and β / β ₀ with a specific catalytic reaction device. Here, the state where there is no cork deposition in the catalyst layer is represented by the subscript 0. As a result, the present inventor has found that there is a relationship as shown in FIG. 3 between the two. The horizontal axis and the vertical axis of FIG. 3 are both logarithmic axes. As shown in FIG. 3, there is a positive correlation between _{η / η 0} and β / β _0.

The present inventor considers this reason as follows. That is, compared to the initial state in which no cork is deposited in the catalyst layer, heat is more likely to be transferred in the catalyst reactor when cork is deposited. The main component of cork is solid carbon, which is a substance with relatively high thermal conductivity, and the cork fills the gaps between the catalyst particles and between the catalyst particles and the inner wall tube of the reactor. Therefore, heat transfer in the catalyst layer is mainly carried out by heat conduction via cork. As the amount of cork deposited increases (that is, the resistance coefficient increases), the thermal transmissivity h, that is, the value of the model constant β also increases. Therefore, it is considered that the relationship shown in FIG. 3 can be obtained.

The relationship of FIG. 3 can be formally expressed by the following equation. The value of the model constant _ai is 0.42 in the example of FIG. A specific method for calculating the flow rate using this correlation will be described later.
β _i = β _{0, i} · (η _i / η _{0, i} ) ^ai
a _i : Model constant

As described above, according to the present invention, the flow rate in a plurality of catalyst reactors arranged in parallel in the heating furnace can be easily calculated by measuring the temperature in the catalyst reactor. Then, based on this flow rate, the blocked state of each catalytic reactor can be detected. Therefore, it is possible to inexpensively and easily detect the blocked state of each catalyst reactor without providing a flow rate or measuring means for each catalyst reactor.

It is explanatory drawing which shows the whole structure of the catalyst reaction apparatus 1 used in 1st to 3rd Embodiment of this invention. It is explanatory drawing which shows the schematic structure of the apparatus in a heating furnace. It is a graph which shows the correlation of a resistance coefficient η and a model constant β. (A) is a side sectional view showing an internal structure of a catalytic reactor. (B) is a plan view which shows the structure of the catalyst cage. (C) is a cross-sectional view on the AA side of (a). (A) is a side view showing the appearance of the catalyst reactor. (B) to (d) are cross-sectional views on the AA side of (a). (A) It is a top view which shows the shape when the catalyst cage is seen from the bottom. (B) is a side sectional view showing the catalyst cage and its peripheral structure. (A) It is a top view which shows the shape of a valve seat, a valve body and the like when viewed from below. (B) is a side sectional view showing a valve seat, a valve body and the like.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. First Embodiment>
(1. Overall configuration)
First, the overall configuration of the catalyst reaction device 1 according to the first embodiment will be described with reference to FIGS. 1 and 2. The catalyst reaction device 1 includes a fluid switching device 110, a gas preheating device 111, a heating furnace device A1, a cooling device 117, a flow rate adjusting device 118, and a blower 119.

The heating furnace device A1 is provided in the heating section A, and includes an inflow collecting pipe 101, a flow meter 112, an inflow pressure meter 113, an inflow thermometer 114, and a plurality of (N in the example of FIG. 1). . N is an integer of 3 or more) The catalyst reactor 2, the deposit removal device 3 in the catalyst layer provided for each catalyst reactor 2, the catalyst layer thermometer 115 provided for each catalyst reactor 2, and the outflow assembly. A pipe 102 and an outflow pressure meter 116 are provided.

The device A1 in the heating furnace is heated by a heating furnace (not shown). As such a heating furnace, for example, a direct-fired heating furnace in which a large number of gas burners are arranged in the furnace can be used. A thermometer for measuring the furnace temperature is installed in the heating furnace at a representative point where the catalyst reactor 2 or the piping does not exist. Then, by controlling the combustion amount of the gas burner, the furnace temperature is adjusted so that the measured value of this thermometer matches the target value.

Therefore, the catalyst reactor 2 constituting the in-heating furnace device A1 is heated from the heating furnace (that is, the outside). As a result, the heat of reaction required for the catalytic reaction is supplied to the catalytic reactor 2. Therefore, the catalyst reactor 2 is an external thermal catalyst reactor. A plurality of catalyst reactors 2 (N in the example of FIG. 1) are arranged in parallel in the heating section A. The catalyst reactor 2 has a structure in which a catalyst is filled in a straight pipe, and the catalyst is fixed as a catalyst layer in the straight pipe as a fixed bed. In addition, a net or the like for preventing the catalyst from falling is provided in the lower part of the straight pipe. One end of the straight pipe is the entry side and the other end is the exit side. Then, the raw material gas is introduced from the inlet side, and a catalytic reaction occurs when the raw material gas passes through the catalyst layer (fixed bed). The raw material gas after the catalytic reaction, that is, the reformed gas, flows out from the outlet side. The detailed configuration of the heating furnace device A1 will be described later.

The fluid switching device 110 is connected to the raw material fluid supply device 100, the non-reactive fluid supply device 200, and the inflow collecting pipe 101. The fluid switching device 110 is a device that switches the gas supplied to the inflow collecting pipe 101 between the raw material gas supplied from the raw material fluid supply device 100 and the non-reactive gas supplied from the non-reactive fluid supply device 200. .. As the fluid switching device 110, for example, two ports on the upstream side are a raw material fluid supply device 100 (more specifically, a pipe extending from the raw material fluid supply device 100) and a non-reactive fluid supply device 200 (more specifically). Can be used as a three-way valve having a structure in which each is connected to a pipe extending from the non-reactive fluid supply device 200) and a port on the downstream side is connected to the inflow collecting pipe 101.

The raw material fluid supply device 100 is a device that supplies the raw material gas to the catalyst reactor 2, and is, for example, a gas holder, a gas generator, or the like. The raw material gas is a gas that is reformed by a catalytic reaction in the catalyst layer described later. In the catalytic reaction targeted by the first embodiment and other embodiments described later, the flow resistance of the catalyst layer can change significantly during the operation. Therefore, examples of the raw material gas include natural gas, naphtha, coke oven gas, and other gases containing hydrocarbons such as coal carbonization gas containing tar. When the raw material gas contains hydrocarbons, the raw material gas is reformed by steam reforming or the like by the catalyst layer. The reformed raw material gas, that is, the reformed gas is recovered by the reaction fluid recovery device 300.

At this time, cork, which is a by-product, may be produced by a catalytic cracking reaction of hydrocarbon, which is a side reaction. Since the cork generated in the catalyst layer is gradually deposited in the space between the catalysts in the catalyst layer (fixed bed), the flow resistance (in this case, the aeration resistance) of the catalyst layer increases during the operation. Further, in the catalytic reaction targeted by the first embodiment and other embodiments described later, the thermal conductivity is orders of magnitude higher than that of the gas passing through the voids in the catalyst layer, and that of the catalyst. Those that produce by-products that are not significantly smaller than the above (for example, 1 W / m · K or more at the catalyst reaction temperature, depending on the catalyst species) are targeted. Cork is an example of a by-product that satisfies such a thermal conductivity condition. Hereinafter, for convenience of explanation, the case where the by-product is cork will be described as an example, but it goes without saying that the by-product is not limited to cork.

In order to ensure the reactivity of steam reforming, the temperature of the catalyst layer, that is, the catalyst layer temperature is set to a high temperature such as 700 ° C. or higher, and all the catalyst reactors 2 satisfy this catalyst layer temperature condition. The reactor temperature T _f of the heating furnace is adjusted as described above. Hereinafter, the catalyst layer temperature of the i-th catalyst reactor 2 is also referred _{to as “catalyst layer temperature Ti”.}

The non-reactive fluid supply device 200 is a device that supplies the non-reactive gas to the catalytic reactor 2, and examples thereof include a gas holder. The non-reactive gas is a gas that does not cause a chemical reaction by the catalyst heated to the catalyst layer temperature. For example, when the steam reforming reaction of the above-mentioned raw material gas is carried out, the non-reactive gas corresponds to an inert gas such as argon, a nitrogen gas or the like. In the first embodiment and other embodiments described later, all the fluids (for example, raw material gas, non-reactive gas, reformed gas) flowing in the catalyst reaction device 1 are gas, but they are liquid. There is no problem at all.

The gas preheating device 111 is a device for preheating the raw material gas or the non-reactive gas introduced into the inflow collecting pipe 101. The raw material gas or non-reactive gas is introduced into the catalyst reactor 2 after being preheated. The gas preheating device 111 is provided at one end of the inflow collecting pipe 101, that is, at the inflow pipe 101a of a single pipe. The gas preheating device 111 is, for example, a heat exchanger. The gas preheating device 111 may be a heating pipe in which the wall surface of the pipeline is directly heated. A fluid transfer device such as a blower may be appropriately provided between the inflow collecting pipe 101 and the raw material fluid supply device 100.

The inflow collecting pipe 101 is a single collecting pipe for supplying a fluid, for example, a raw material gas or a non-reactive gas, to all the catalytic reactors 2. One end of the inflow collecting pipe 101 is a single inflow pipe 101a, and the inflow pipe 101a is connected to the fluid switching device 110. The other end is a plurality of (N) inflow branch pipes 101b, and the end on the inlet side of the catalyst reactor 2 is connected to each inflow branch pipe 101b. The inflow pipe 101a and the inflow branch pipe 101b are connected by a connecting pipe 101c.

The catalyst reactor 2 is a straight tubular device having a built-in catalyst layer which is a fixed bed, and a plurality of catalyst reactors 2 are arranged in parallel in the heating section A. The inlet end of the catalyst reactor 2 is connected to the inflow branch pipe 101b of the inflow collecting pipe 101, and the outlet end is connected to the outflow branch pipe 102b of the outflow collecting pipe 102. The catalyst reactor 2 reforms the raw material gas by a catalytic reaction using the catalyst layer. Then, the catalyst reactor 2 discharges the reformed raw material gas, that is, the reformed gas, into the outflow collecting pipe 102. The detailed configuration of the catalyst reactor 2 will be described later.

The catalyst layer in-catalyst deposit removing device 3 is provided for each catalyst reactor 2 and removes by-products such as cork deposited in the catalyst layer, that is, deposits during operation. The deposit removing device 3 in the catalyst layer can be driven independently of each other. A specific example of the deposit removing device 3 in the catalyst layer will be described later, but for example, the device disclosed in Patent Documents 1 and 2 can be used without particular limitation.

The outflow collecting pipe 102 is a single collecting pipe for collecting the fluids flowing out from all the catalytic reactors 2, such as a reforming gas or a non-reactive gas, and causing them to flow downstream. One end of the outflow collecting pipe 102 is a plurality of (N) outflow branch pipes 102b, and the outlet end of the catalyst reactor 2 is connected to each outflow branch pipe 102b. The other end of the outflow collecting pipe 102 is a single outflow pipe 102a. The outflow pipe 102a and the outflow branch pipe 102b are connected by a connecting pipe 102c. The outflow pipe 102a is connected to the reaction fluid recovery device 300 via a cooling device 117, a flow rate adjusting device 118, and a blower 119. Therefore, the reformed gas flowing out from the outflow collecting pipe 102 is recovered by the reaction fluid recovery device 300 through the cooling device 117, the flow rate adjusting device 118, and the blower 119. The reaction fluid recovery device 300 is composed of, for example, a gas holder or the like.

Flowmeter 112 is provided in the inlet pipe 101a of the heating section A, for measuring the flow rate _{Q T} of the inlet manifold pipe 101. Flow rate Q _T is a total amount of gas introduced into the catalytic reactor 2. Examples of the flow meter 112 include a device using an orifice. Specifically, an orifice is provided in the inflow pipe 101a. Then, the flow meter 112, the flow velocity measured based from around the orifice differential pressure with the principles of Bernoulli, converted the value to the flow rate Q _T. Details will be described later, in the first embodiment, as the flow rate Q _T, using a flow rate of non-reactive gases. Therefore, the flow meter 112 may be provided at the outlet of the non-reactive fluid supply device 200. In apparatus system of the present embodiment, since the gas temperature is varied depending on the location and time, the flow rate Q _T, for example, can be used in terms of flow rate at standard conditions.

The inflow thermometer 114 is provided in, for example, the connecting pipe 101c, and measures the gas temperature in the inflow collecting pipe 101, that is, the inflow temperature. The catalyst layer thermometer 115 is provided for each catalyst reactor 2 and measures the temperature inside the catalyst layer. Thermocouples can be used for these thermometers. In this case, for example, the temperature detection unit is inserted into the connecting pipe 101c or the catalyst reactor 2, and the signal line is pulled out of the heating furnace through the pipe wall of the connecting pipe 101c or the pipe wall of the catalyst reactor 2. Then, the signal line is connected to the temperature converter provided outside the heating furnace. The temperature transducer measures and records the temperature. The temperature detection unit of the catalyst layer thermometer 115 is preferably arranged in the center of the catalyst layer, but for convenience of design, the catalytic reaction on the downstream side in the catalyst layer and below the catalyst layer. It may be provided in the space inside the vessel or in the space sandwiched between the catalyst layer and the outer wall surface of the catalyst reactor 2.

The inflow pressure gauge 113 is provided in, for example, the inflow pipe 101a in the heating section A, and measures the gas pressure in the inflow collecting pipe 101. The outflow pressure gauge 116 is provided in the outflow pipe 102a in the heating section A, and measures the gas pressure in the outflow collecting pipe 102. These constitute a differential pressure measuring device. As a method of realizing these pressure gauges, for example, pressure conduits are provided in the inflow pipe 101a and the outflow pipe 102a, and the end of the pressure conduit is pulled out of the heating furnace, and a commercially available diaphragm type pressure gauge is attached to this end. You can connect it.

These measuring instruments included in the catalyst reactor 1 are often installed as standard for operation management in the technical field related to the industrial external thermal catalyst reactor 2.

The cooling device 117 removes condensed components (for example, tar) in the reforming gas and can supply the reforming gas to the flow rate adjusting device 118 and the reaction fluid recovery device 300 in the subsequent stage (eg, less than 80 ° C.). ). Specific examples of the cooling device 117 include a heat exchanger and a scrubber. The cooled reformed gas is introduced into the blower 119 through the flow rate adjusting device 118.

The flow rate adjusting device 118 is a device that adjusts the flow rate of the raw material gas, which is the sum of the flow rates of the raw material gas in all the inflow branch pipes 101b, so as to be the target value. The flow rate adjusting device 118 is, for example, a valve that adjusts the flow rate of the reformed gas, and includes a driving device such as an electric motor or an air cylinder. A commercially available flow control valve can be used.

The blower 119 supplies (blows) the reformed gas cooled by the cooling device 117 to the reaction fluid recovery device 300. The blower 119 is also not particularly limited, and may be a commercially available turbo type / positive displacement type blower. By adjusting the set values of the blower 119 and the flow rate adjusting device 118, the raw material gas flow rate can be adjusted to be the target value.

The catalytic reaction device 1 has been industrially put into practical use, and is, for example, a general material and structure used in an external thermal catalytic reaction device for steam reforming of hydrocarbons (for example, natural gas). Realized by.

(2. Specific example of catalytic reactor)
As the catalyst reactor 2, for example, those disclosed in Patent Documents 1 and 2 can be used without particular limitation. Hereinafter, some specific examples of the catalyst reactor 2 will be described. In the example described below, the catalyst layer deposit removing device 3 is incorporated in the catalyst reactor 2.

(2-1. First example)
First, a first example of the catalyst reactor 2 will be described with reference to FIG. The first example corresponds to the catalytic reactor disclosed in the first embodiment of Patent Document 1. Therefore, the parameters disclosed in Patent Document 1 can be appropriately applied to the parameters not disclosed here.

As shown in FIG. 4, the catalyst reactor 2 according to the first example is driven by a reaction vessel 40, an inflow path 41, an outflow path 42, a catalyst layer 43, a catalyst cage 44, a mandrel 48, and the like. A device 49 is provided. The catalyst cage 44 includes a plurality of rods 44a arranged in parallel with each other and a rod fixture 44b for connecting the ends of the rods 44a. Of these, the catalyst cage 44, the mandrel 48, and the driving device 49 realize the deposit removing device 3 in the catalyst layer.

(Shape of reaction vessel)
The reaction vessel 40 may have any shape as long as it has openings at both upper and lower ends and can accommodate the catalyst between these openings. The upper opening leads to the inflow path 41 and corresponds to the inflow port of the raw material gas for the catalytic reaction to the reaction vessel 40. The lower opening leads to the outflow passage 42 and corresponds to the outflow port of the reformed gas from the reaction vessel 40. The reaction vessel 40 can have a shape such as a cylindrical shape or a square duct shape. In the following, a square duct-shaped reaction vessel will be described as an example.

In the description of the catalytic reactor 2 according to the first example, the "central axis of the container" is defined as the center of gravity of the horizontal cross section of the container connected in the vertical direction. The "reaction vessel thickness" corresponds to the minimum length of the reaction vessel in the horizontal section, and the "reaction vessel width" is the maximum length of the reaction vessel in the horizontal plane. Corresponds to. If the container is cylindrical, the "width" and "thickness" of the container may be replaced with "diameter".

(Catalyst cage)
The catalyst cage 44 holds the catalyst layer 43 on the entire lower surface of the catalyst layer 43 in the reaction vessel 40 and has air permeability. As the catalyst cage 44, a net, a punching metal, a rod in which both rods are fixed in parallel with each other in the horizontal direction so as to create a space between the rods, or the like can be used. .. The catalyst cage 44 shown in FIG. 4 is an example of one manufactured by fixing both ends of a plurality of rods 44a with rod fixtures 44b.

(Catalyst layer drive mechanism)
In the present invention, the catalyst layer 43 is raised and lowered in the reaction vessel 40 by raising and lowering the catalyst cage 44. Therefore, the reaction vessel 40 is equipped with a drive device 49 for raising and lowering the catalyst cage 44. As the drive device 49, a general drive mechanism such as an elevating device using gears such as an air cylinder and a rack and pinion can be used. The catalyst cage 44 is coupled to the drive device 49 using the mandrel 48. When the drive device 49 is operated, the entire cage 44 moves along the axis of the reaction vessel 40 (the central axis of the reaction vessel 40), and the entire catalyst layer 43 also moves up and down along the axis of the reaction vessel 40. Move to.

At least a part of the mandrel 48 on the catalyst cage 44 side needs to be inside the reaction vessel 40, the inflow passage 41, and the outflow passage 42. The drive device 49 can be provided outside the reaction vessel 40. When the reaction vessel 40 is arranged in a heating device (not shown) such as a heating furnace, the drive device 49 may be provided outside the heating device. In this case, while a commercially available lifting device can be used, it is necessary to seal the portion where the mandrel 48 penetrates the reaction vessel 40 with a high temperature packing or the like.

When the entire drive device 49 is provided in the reaction vessel 40 as shown in FIG. 4, the drive device 49 is heat-resistant and corrosion-resistant in order to protect the drive device 49 from, for example, high temperature and corrosive substances in the reaction vessel 40. Must be. This can be achieved, for example, by making the entire air cylinder of the drive device 49 made of a heat-resistant alloy such as Hastelloy (registered trademark). In this case, the supply air pipe (not shown) to the air cylinder penetrates the reaction vessel 40, but since this portion is a non-movable part, the pipe may be sealed by welding all around.

(Raising and lowering the catalyst layer)
The entire upper surface of the catalyst cage 44 is filled with a catalyst to form a catalyst layer. The side surface of the catalyst layer thus formed is always in contact with the inner wall surface of the reaction vessel 40. When the catalyst cage is raised, an upward force is applied to the catalyst layer, and a downward frictional force is generated from the inner wall surface of the reaction vessel on the side surface of the catalyst layer. As a result, in the catalyst layer, since the catalyst near the wall surface is largely constrained by the wall surface, the amount of upward movement is smaller on average than the amount of increase of the catalyst cage, and the filling rate of the catalyst particles in this portion is small. Rise. On the other hand, since the constraint on the wall surface is weaker in the central portion of the catalyst layer, which is far from the wall surface, the amount of movement of the catalyst layer upward is relatively large, and the increase in the filling rate of the catalyst particles in this portion is small. As a result, during the ascent of the catalyst cage, shear deformation of the catalyst layer occurs from the vicinity of the wall surface to the center, and relative displacement between the catalyst particles occurs everywhere in the catalyst layer. Since the space between the catalyst particles is deformed by this relative displacement, the by-product coke (that is, by-product) deposited in this space can be crushed and extruded and discharged to the outside of the catalyst layer. In this way, the average filling rate of the catalyst layer increases as the catalyst cage rises.

On the other hand, when the catalyst cage is lowered, the average filling rate of the catalyst layer is lowered to the level before the start of raising and lowering. This is because when the catalyst cage is lowered, it gradually falls from the lower catalyst layer due to the restraint of the wall surface, so that the average distance between the catalyst particles increases during the lowering of the catalyst layer, and the positional relationship between the catalysts increases. Since a part of the catalyst layer is maintained until after the lowering of the catalyst layer is completed, the filling rate of the catalyst layer is lowered. Further, as the spacing between the catalyst particles increases as the filling rate decreases when the catalyst layer descends, the by-product coke deposited between the particles may move and be discharged to the outside of the catalyst. As a result, even if the catalyst layer is repeatedly raised and lowered, the filling rate does not continue to increase and close-packing is not achieved, and cork removal can be continued for a long period of time. In this way, the cork deposited in the catalyst layer can be removed by raising and lowering the catalyst layer. Further, since the principle for removing cork from the catalyst layer in this method is to deform the space between the catalyst particles, the ascending / descending speed of the catalyst layer does not necessarily have to be high. A sufficient effect can be obtained at an ascending / descending speed of about 10 mm / s. Further, the relative displacement amount between the particles may be about the size of the particles (for example, 10 mm).

(Inflow route, outflow route)
The inflow path 41 is connected to the inflow branch pipe 101b. Therefore, the raw material gas is introduced into the inflow path 41. The arrow P1 in FIG. 4 indicates the flow of the raw material gas (in the case of a downward flow in the catalyst layer). The outflow branch pipe 102b is connected to the outflow passage 42. The reformed gas is introduced into the outflow passage 42. After that, the reformed gas is introduced into the cooling device 117 through the outflow branch pipe 102b.

(Catalyst layer)
The catalyst layer 43 is formed by filling and laminating the catalyst particles on the catalyst cage 44 in the reaction vessel 40. The catalyst particles serve as a catalyst for reforming the raw material gas, and the raw material gas is reformed when it comes into contact with the catalyst particles. For example, when a catalytic reaction occurs on the catalyst particles, the water vapor and tar gas in the raw material gas are reformed to generate carbon monoxide gas, hydrogen gas, and cork.

The catalyst particles constituting the catalyst layer 43 may be any catalyst as long as it can reform the raw material gas (for example, steam reforming or cracking). For example, when the raw material gas contains a hydrocarbon, a Ni-alumina-based catalyst, a Ni-magnesia-alumina-based catalyst, or the like can be used as the catalyst particles.

(2-2. Second example)
Next, a second example of the catalyst reactor 2 will be described with reference to FIGS. 5 to 7. The second example corresponds to the catalytic reactor disclosed in the second embodiment of Patent Document 1. Therefore, the parameters disclosed in Patent Document 1 can be appropriately applied to the parameters not disclosed here.

The catalyst reactor 2 includes a reaction vessel 10, an inflow passage 11, an outflow passage 12, a catalyst layer 13, a catalyst cage 14, a valve seat 15, a vent hole 16, a valve body 17, and a mandrel 18. , A heat insulating material 19, a connecting pipe 20, and a driving device 21. The valve seat 15, the vent hole 16, the valve body 17, and the mandrel 18 function as a gas shutoff portion 3a. Further, the catalyst cage 14, the mandrel 18, the connecting pipe 20, and the driving device 21 realize the catalyst layer deposit removing device 3.

(Reaction vessel)
The reaction vessel 10 is a cylindrical member that houses the catalyst layer 13, the catalyst cage 14, the valve seat 15, the vent holes 16, the valve body 17, and the mandrel 18. By forming the reaction vessel 10 into a cylindrical shape, distortion in the radial direction (direction perpendicular to the length direction) is unlikely to occur even at high temperatures. Of course, the shape of the reaction vessel 10 may be changed to another shape for convenience of design or the like. For example, the reaction vessel 10 may have a square tubular shape having a regular polygonal horizontal cross section and an elliptical tubular shape having an elliptical horizontal cross section.

(Inflow route)
The inflow path 11 is connected to the reaction vessel 10 at the upper end of the reaction vessel 10. That is, a ventilation hole 11a is formed at the upper end of the reaction vessel 10, and the inflow path 11 and the reaction vessel 10 are connected to each other through the ventilation hole 11a. The inflow path 11 is connected to the inflow branch pipe 101b, and the raw material gas generated from the raw material fluid supply device 100 is introduced into the reaction vessel 10. The arrow P1 indicates the flow direction of the raw material gas.

(Outflow route)
The outflow channel 12 is connected to the reaction vessel 10 at the lower end of the reaction vessel 10. That is, a ventilation hole 12a is formed at the lower end of the reaction vessel 10, and the outflow passage 12 and the reaction vessel 10 are connected to each other through the ventilation hole 12a. The outflow passage 12 is connected to the outflow branch pipe 102b, and the reformed gas generated in the reaction vessel 10 is introduced into the dust collector 6. The arrow P2 indicates the flow direction of the reformed gas.

Since the inflow path 11 and the outflow path 12 are arranged on the side of the catalyst reactor 2, interference with the mandrel 18 penetrating the catalyst reactor 2 up and down can be avoided. Here, the catalyst reactors 2 may be connected in parallel by sharing the inflow path 11 and the outflow path 12 of each catalyst reactor 2 between the catalyst reactors 2.

(Catalyst layer)
The catalyst layer 13 is provided in the reaction vessel 10. The catalyst layer 13 is formed by filling and laminating the catalyst particles on the catalyst cage 14 in the reaction vessel 10. The catalyst particles serve as a catalyst for reforming the raw material gas, and the raw material gas is reformed when it comes into contact with the catalyst particles. For example, when a catalytic reaction occurs on the catalyst particles, the water vapor and tar gas in the raw material gas are reformed to generate carbon monoxide gas, hydrogen gas, and cork.

Further, the catalyst layer 13 is in contact with the inner wall surface of the reaction vessel 10. Therefore, when the catalyst layer 13 is moved up and down, the upper part of the catalyst layer 13 is delayed to the lower part due to the effect of wall friction. Therefore, the filling rate of the catalyst layer 13 temporarily decreases. At this time, since the average gap between the catalyst particles expands, the removal gas reaches a part where the removal gas is difficult to pass when the catalyst layer is stationary (eg, the catalyst particles directly above the catalyst cage), and the removal gas is there. By-products can be removed.

Further, the catalyst layer 13 is formed in three layers in the reaction vessel 10. Then, the catalyst layer 13 of each layer is held by the catalyst cage 14. By forming the catalyst layer 13 in a multilayer structure in this way, the load applied to each catalyst cage 14 can be reduced. Of course, the number of layers of the catalyst layer 13 is not limited to three.

The catalyst particles constituting the catalyst layer 13 may be any catalyst as long as it can reform the raw material gas (for example, steam reforming or cracking). For example, when the raw material gas contains a hydrocarbon, a Ni-alumina-based catalyst, a Ni-magnesia-alumina-based catalyst, or the like can be used as the catalyst particles. The size of the catalyst particles may be such that they do not pass through the ventilation holes 14c of the catalyst cage 14, which will be described later.

(Catalyst cage)
The catalyst cage 14 is a member that holds the catalyst layer 13, and is provided for each catalyst layer 13. The catalyst cage 14 is fixed to the mandrel 18 described later, and moves up and down integrally with the mandrel 18.

The catalyst cage 14 holds the catalyst layer 13 on the entire lower surface of the catalyst layer 13 in the reaction vessel 10 and has air permeability. Specifically, the catalyst cage 14 needs to have a structure for circulating various gases (raw material gas and reformed gas) while preventing the catalyst particles from falling. Specifically, as shown in FIG. 6, the catalyst cage 14 includes a plurality of ring-shaped members 14a and a connecting member 14b that connects the ring-shaped members 14a to each other. The ring-shaped members 14a have different diameters from each other and are arranged concentrically on the connecting member 14b. Here, the center point of each ring-shaped member 14a is arranged on the central axis of the mandrel 18. The cross-sectional shape (cross-section perpendicular to the circumferential direction) of the ring-shaped member 14a is not particularly limited, but is preferably rectangular from the viewpoint of strength. Further, a ventilation hole 14c is formed between the ring-shaped members 14a. Various gases and by-products pass through the vents 14c.

The connecting member 14b connects the ring-shaped members 14a to each other and fixes them to the mandrel 18. That is, the connecting member 14b is a member that extends radially from the mandrel 18. The cross section (cross section perpendicular to the length direction) of the connecting member 14b is also preferably rectangular. By increasing the cross-sectional area of the ring-shaped member 14a and the connecting member 14b, the strength of the catalyst cage 14 can be increased. The catalyst cage 14 may be, for example, a net, a punching metal, or the like processed into the same shape as the horizontal cross-sectional shape of the reaction vessel 10.

The catalyst cage 14 is preferably made of a metal material having heat resistance, corrosion resistance, strength against bending and shearing, and toughness at both normal temperature and when heated to the temperature of the catalytic reaction. Examples of such metal materials include stainless steel, nickel alloys such as Hastelloy (registered trademark) and Inconel (registered trademark), titanium, and titanium alloys.

(Valve seat, vent)
Next, as shown in FIG. 7, the valve seat 15 is provided on the inner wall surface of the reaction vessel 10. The valve seat 15 is a member that horizontally partitions the space inside the reaction vessel 10. Further, a ventilation hole 16 is formed in the central portion of the valve seat 15 so as to vertically penetrate the valve seat 15. The mandrel 18 penetrates the ventilation hole 16, and the raw material gas can pass through the ventilation hole 16. That is, the diameter of the ventilation hole 16 is larger than the diameter of the mandrel 18. Further, a substantially conical notch is formed on the lower end surface of the valve seat 15. Therefore, a concave shape is formed on the lower end surface of the valve seat 15. The material of the valve seat 15 may be the same as that of the catalyst cage 14.

(Valve body)
The valve body 17 is a member that moves up and down integrally with the mandrel 18, and has a conical trapezoidal shape. The valve body 17 can open or close the ventilation hole 16 by moving up and down together with the mandrel 18. For example, the valve body 17 opens the ventilation hole 16 when it exists at the position shown by the solid line in FIG. 7B (this position corresponds to the opening position 18a described later). In this case, the raw material gas can reach the catalyst layer 13 through the ventilation holes 16. On the other hand, the valve body 17 closes the ventilation hole 16 when it exists at the position indicated by the alternate long and short dash line in FIG. 7 (b) (this position corresponds to the closing position 18b described later). In this case, since the inflow path 11 and the catalyst layer 13 in the reaction vessel 10 are blocked by the valve seat 15 and the valve body 17, the raw material gas cannot reach the catalyst layer 13. That is, the distribution of the raw material gas to the reaction vessel 10 is blocked. The material of the valve body 17 may be the same as that of the catalyst cage 14.

The broken line 17d in FIG. 7A indicates the upper end of the valve body 17 in which the ventilation hole 16 is closed, and the broken line 17e and the straight line 17b in FIG. 7B are the valve body 17 in which the ventilation hole 16 is closed. The contact line between the valve seat 15 and the valve seat 15 is shown. This contact line is circular.

As described above, both the valve seat 15 and the valve body 17 have an axisymmetric shape (contact line 17b is circular). Therefore, the blocking property of the raw material gas can be further improved. For convenience of design and the like, the contact line 17b may have a smooth shape such as an ellipse and no corners. In this case, the horizontal cross-sectional shape of the valve seat 15 and the horizontal cross-sectional shape of the notch of the valve body 17 may be elliptical or the like.

(Mandrel)
The mandrel 18 is a cylindrical or cylindrical member (that is, a round bar or a circular tube) extending vertically in the reaction vessel 10. A catalyst cage 14 and a valve body 17 are fixed to the mandrel 18, and the catalyst cage 14 and the valve body 17 move up and down together with the catalyst cage 14. Further, the upper end of the mandrel 18 is connected to the drive device 21 via a heat insulating material 19. The mandrel 18 is moved up and down by the drive device 21. Specifically, the mandrel 18 has an open position 18a in which the valve body 17 opens the ventilation hole 16 as shown in FIG. 5 (b), and the valve body 17 has the ventilation hole as shown in FIG. 5 (c). It goes up and down between the closed position 18b that closes 16.

Further, the mandrel 18 can move up and down between the intermediate position 18c shown in FIG. 5D and the open position 18a shown in FIG. 5B when the by-product is removed. The intermediate position 18c is set between the open position 18a and the closed position 18b. In the example shown in FIG. 5, the intermediate position 18c is set at the midpoint between the open position 18a and the closed position 18b, but it goes without saying that the intermediate position 18c may be set at another position. is there.

The method of setting the intermediate position is not particularly limited, and examples thereof include a method of providing a limit switch at a position corresponding to the intermediate position in the air cylinder described above. More specifically, a 3-position type air cylinder having such a limit switch may be used as the drive device 21. Further, a 3-position type air cylinder may be realized by connecting a plurality of 2-position type air cylinders in series. The number of intermediate positions may be plural. In this case, the number of positions of the drive device 21 increases according to the number of intermediate positions.

The drive device 21 stops the mandrel 18 at the closed position 18b when the raw material gas is shut off, and stops the mandrel 18 at the open position 18a when the raw material gas is reformed, by being controlled by a speed increasing device (not shown). Further, the drive device 21 raises and lowers the mandrel 18 between the intermediate position 18c and the open position 18a when removing by-products. The drive device 21 is controlled by a reactor group control device (not shown). Thereby, in the present embodiment, the catalyst layer 13 can be raised and lowered without interrupting the flow of the raw material gas. That is, in the present embodiment, the mandrel 18 is moved up and down between the intermediate position 18c and the open position 18a.

As described above, when the mandrel 18 is in the open position 18a (or the intermediate position 18c), the valve body 17 is not in contact with the valve seat 15 and the ventilation hole 16 is opened. In this case, the raw material gas is introduced into the catalyst reactor 2. Further, when the mandrel 18 is in the closing position 18b, the valve body 17 comes into contact with the valve seat 15 and the ventilation hole 16 is closed. In this case, the raw material gas is shut off from the catalyst reactor 2. Then, when the mandrel 18 is in the open position 18a (or the intermediate position 18c), the gas shutoff portion 3a is in the open state, and when the mandrel 18 is in the closed position 18b, the gas shutoff portion 3a is in the closed state.

The heat insulating material 19 is a member provided to make it difficult for the heat of the mandrel 18 to be transferred to the driving device 21. The heat insulating material 19 penetrates the upper end surface 10a of the reaction vessel 10 and extends into the connecting pipe 20. The heat insulating material 19 is connected to the drive rod 21a of the drive device 21 in the connecting pipe 20. The lower end of the heat insulating material 19 is arranged in the reaction vessel 10 when the mandrel 18 is raised and lowered. As a result, the heat of the mandrel 18 is less likely to be transferred to the drive device 21 even while the mandrel 18 is moving up and down. The heat insulating material 19 is made of, for example, ceramics. The structure of the heat insulating material 19 may be a structure in which the heat insulating material is sandwiched between the flanges, or a structure in which a large number of a plurality of metal plates are simply stacked in the axial direction. In the latter case, the heat flux in the axial direction can be suppressed by utilizing the contact thermal resistance between the metal plates. The heat insulating material 19 may be a high temperature packing.

(Connecting pipe and drive device)
The connecting pipe 20 is a tubular member that connects the reaction vessel 10 and the driving device 21. The drive device 21 is a member that raises and lowers the mandrel 18 between the open position 18a, the closed position 18b, and the intermediate position 18c, and includes a drive rod 21a, a cylinder 22, and a piston 23. Therefore, the drive device 21 is an elevating device using a so-called 3-position type air cylinder. The drive rod 21a is connected to the mandrel 18 via a heat insulating material 19. The cylinder 22 is a member in which the piston 23 is housed, and the piston 23 moves up and down in the cylinder 22 by the gas supplied into the cylinder 22. A drive rod 21a is connected to the piston 23. The drive rod 21a moves up and down in conjunction with the piston 23. As a result, the drive device 21 raises and lowers the mandrel 18. When the piston 23 reaches the lower end of the cylinder 22, the mandrel 18 reaches the open position 18a, and when the piston 23 reaches the upper end of the cylinder 22, the mandrel 18 reaches the closed position 18b. At the intermediate position, at 18c, the pressure above and below the cylinder is balanced to maintain the cylinder at a predetermined stop position between the open position and the closed position. Of course, the drive device 21 is not limited to the air cylinder as long as the mandrel 18 can be raised and lowered in the above-described manner. For example, the drive mechanism of the drive device 21 may be a rack and pinion or the like.

The drive device 21 is provided outside the reaction vessel 10 as shown in FIG. Further, the drive device 21 may be arranged in a heating device (a device for heating the reaction vessel 10 or the like). In this case, in order to protect the drive device 21 from high temperature and corrosive substances, it is preferable that the drive device 21 is made of a material having high heat resistance and corrosion resistance. For example, the entire air cylinder of the drive device 21 may be made of a heat-resistant alloy such as Hastelloy (registered trademark). In this case, the pipe (not shown) that supplies gas to the air cylinder penetrates the reaction vessel 10, but since this portion is a non-movable part, the pipe may be sealed by welding all around. Since a part of the catalyst cage 14 may bite into the catalyst layer 13 and cannot fall freely when the mandrel 18 is raised, the drive device 21 is driven not only when the mandrel 18 is raised but also when it is lowered. Is preferable. The drive device 21 is driven by control by a reactor group control device (not shown).

In the second example, among the plurality of catalyst reactors 2, the gas shutoff portion 3a of any of the catalyst reactors 2 can be selectively closed. For example, the gas shutoff portion 3a of any one of the catalyst reactors 2 can be opened, and the gas shutoff portion 3a of the remaining catalyst reactor 2 can be closed. As a result, a large flow rate of the raw material gas can be circulated through the specific catalyst reactor 2, and the by-products in the catalyst reactor 2 can be easily removed.

(3. Method for detecting blockage of catalytic reactor)
Next, a method for detecting blockage of the catalyst reactor 2 will be described. The blockage detection method comprises the first to fourth operations. The blockage detection method and the subsequent blockage elimination method may be performed at any timing during normal (regular) operation of reforming the raw material gas into reformed gas. In the first embodiment and other embodiments described later, the unit of temperature is ° C.

(3-1. First operation)
In the first operation, the fluid switching device 110 is operated to supply the non-reactive gas to the inflow collecting pipe 101, and the non-reactive gas is passed through all the catalytic reactors 2. The gas preheating device 111 is adjusted so that the inflow temperature at this time becomes the first inflow temperature _Tin1. At the same time, the flow rate Q _{T of the inflow collecting tube 101 and the catalyst layer temperature T 1, i} measured by the catalyst layer thermometer 115 of each catalyst reactor 2 are recorded (subscript i is the catalyst reactor number and subscript). The character 1 indicates the time of the first operation, and the subscript 2 described later indicates the time of the second operation. The meanings of the subscripts are the same below.) Here, in order to save the time required for this operation, _{it is preferable that T1 and i} are inflow temperatures realized under the furnace temperature conditions during the normal catalyst reaction operation.

(3-2. Second operation)
As a second operation, by adjusting the gas preheater 111, is set to a different second inlet temperature T _in2 is the inlet temperature to the first inlet temperature T _in1 above. _{At this time, the catalyst layer temperatures T2 and i} measured by the catalyst layer thermometer 115 of each catalyst reactor 2 are recorded. The inflow temperature _Tin2 may be higher or lower than the inflow temperature _{Tin1, but is preferably lower.} Further, in order to sufficiently secure the accuracy at the time of calculating the flow rate in the catalyst reactor 2 described later, _{the temperature difference between the inflow temperature Tin2} and the inflow temperature _Tin1 is preferably 10 ° C. or more. On the other hand, if this temperature difference is excessive, it takes a significant amount of time to return to the normal catalytic reaction operation after the main operation is completed, so this temperature difference is preferably 50 ° C. or less.

The reason for providing a temperature difference thus the inlet temperature T _in2 between inlet temperature T _in1 is as follows. As described above, the inflow temperature _{Tin 1} is generally set to a temperature close to the furnace _{temperature T f.} Details will be described later, but in the first embodiment, the temperature difference of the non-reactive gas in the piping system from the inflow collecting pipe 101 to the catalytic reactor 2 (temperature difference between the _{inflow temperature Tin 2} and the inflow temperature _{Tin 1).} ) Is used to estimate the gas flow rate in the pipeline. Therefore, the inflow temperature _Tin2 generally needs to be set to a value sufficiently different from the inflow temperature _Tin1 (that is, the furnace temperature _Tf). For convenience of explanation, hereinafter, although inlet temperature T _in2 will be described on the assumption that it is a value lower than the inlet temperature T _in1, even when inlet temperature T _in2 is higher than the inflow temperature T _in1 However, the flow rate and the like can be calculated using the same formula that appears in the following explanation. After the second operation is completed, it may be returned to the normal catalytic reaction operation.

Since the catalytic reaction is stopped during these first and second operations, it is preferable that these operations are performed infrequently from the viewpoint of productivity. For example, the operation time required for the first operation and the second operation can be set to a total of 10 minutes, and the execution frequency can be set to once every two hours.

(3-3. Third operation (operation related to calculation of flow rate of catalytic reactor))
Subsequently, the third operation is performed. The third operation and the fourth operation described later may be performed in parallel with the regular operation or offline.

In the third operation, the flow rate in each catalytic reactor 2 is calculated by the following procedure using the measurement data obtained in the first and second operations. First, in the i-th catalytic reactor 2 (hereinafter, also referred to as “catalytic reactor i”), the model constant β _i defined by the following equation (1) is introduced. Considering the unit of each parameter, the model constant β _i has a unit (m ³ / s) equivalent to the flow rate.
β _i = hLX _i / (ρC _p ) (1)
h: Thermal transmission rate (W / (m ² · K))
L: Perimeter of piping (m)
ρ: Gas density (kg / m ³ )
Cp: Constant pressure specific heat of gas (J / (kg · K))
X _i : Length of the pipe between the inflow pipe and the catalyst reactor (m), specifically, the distance from the inflow temperature measurement point in the inflow collecting pipe 101 to the catalyst layer temperature measurement point of the catalyst reactor i.

Equation (1) is obtained by modeling the heat transfer along the flow direction of the non-reactive gas passing between the inflow collecting pipe 101 and the catalyst reactor i as follows. First, the coordinates of the gas flow direction in the pipeline between the inflow collecting pipe 101 and the catalyst reactor i and the subsequent catalyst reactor i are x, and the starting point (x = 0) is the inflow in the inflow collecting pipe 101. temperature measurement point (the temperature at this point and the temperature T _in), the catalyst layer temperature measuring points of the endpoints catalytic reactor i (x = X _i, the temperature at this point as the temperature T _i), the furnace The temperature _{is defined as T f} , and the representative temperature in the pipeline at the position x (for example, the cross-sectional average temperature) is defined as the pipeline temperature T. It is assumed that heat is transferred to the non-reactive gas locally in the conduit through the conduit, the wall surface of the catalyst reactor, and the catalyst layer based on the temperature difference between _{T f and T, and the heat flux q'is assumed.} 'Is assumed to be expressed by the following equation (2) per unit pipe length.
q'' = hL (T _f −T) (2)

Here, h is the thermal transmission coefficient, which is generally a function of the position x. For the sake of simplicity, in this first embodiment, it is assumed that h is a constant value in the specific catalytic reactor i for at least the period of the first and second operations. Due to this heat flux, the temperature T (temperature of the non-reactive gas) in the pipeline and the catalytic reactor i rises as it progresses in the flow direction when the gas flow is regarded as an incompressible fluid in this section. The rate of temperature rise can be expressed by the following equation (3) from the heat balance.
_{ρCpQ i dT / dx = hL (} T f -T) (3)
ρ: Density of non-reactive gas (kg / m ³ )
Cp: Constant pressure specific heat of non-reactive gas (J / (kg · K))
Q _i : Flow rate of non-reactive gas in catalytic reactor i (m ³ / s)

Even when the pressure change of the raw material gas is large in the entire catalytic reaction apparatus 1 and the raw material gas is not an incompressible fluid, it is generally small to set a large flow rate change and density change in this section, so that the raw material In many cases, the gas can be regarded as a substantially incompressible fluid (generally, it is said that a gas can be treated as an incompressible fluid when the density change is 10% or less). Therefore, the non-reactive gas can be regarded as an incompressible gas here as well.

Temperature change from inlet manifold pipe 101 until the catalyst reactor 2 is a relatively small, and, [rho, Cp, Solving this differential equation for Q _i is constant, which is the end point of the channel to be considered for the catalyst the catalyst layer temperature _{T i} of the layer temperature measuring point (x = X _i) is expressed by the following equation (4).
_{T i = T f - (T} f -T in) exp [-hLX i / (ρCpQ i)] (4)
X _i : x at the catalyst layer temperature measurement point in the catalyst reactor i
_{However, T = T in (x =} 0)
T = _Ti (x = X _i )

Here, in the mathematical formula (4), hLX _i / (ρCp) is defined _{as β i.} As a result, the model constant β _i is obtained. Further, the mathematical formula (4) is expressed as follows using _{β i.}
T _i = T _f- (T _f- T _in ) exp [-β _i / Q _i ] (5)

Then, the inlet temperature _{T in1} and the catalyst layer temperature _{T 1, i} obtained in the first operation, the inlet temperature _{T in2} and the catalyst layer temperature _{T 2, i} obtained in the second operation, the formula (5 ), The following equations (5-1) and (5-2) are obtained.
_{T 1, i = T f -} (T f -T in1) exp [-β i / Q i] (5-1)
_{T 2, i = T f -} (T f -T in2) exp [-β i / Q i] (5-2)

Subtracting the equation (5-1) from the equation (5-2), and arranging for the further flow _{Q i,} the equation (6) below is obtained.
Q _i = -β _i / Ln [(T _{2, i} −T _{1, i} ) / (T _in2- T _in1 )] (6)
T _{1, i} : Catalyst layer temperature during the first operation _Ti
T _{2, i} : Catalyst layer temperature during the second operation _Ti
T _in1 : Inflow temperature T during the first operation
T _in2 : Inflow temperature T during the second operation

Therefore, in the third operation, the flow rate Qi in the catalyst reactor _i (specifically, the flow rate in the inflow branch pipe 101b leading to the catalyst reactor i) is calculated using the equation (6).

Here, although the model constant β _i is defined by the equation (1), it is necessary to individually obtain the physical property value and the heat transfer characteristic value on the right side of the equation (1) and substitute them into the equation (1) in order to obtain _{the β i.} Is not always.

In the first embodiment, a fixed value is _{used for β i} used in the equation (6). A _{method for determining the value of β i} is obtained, for example, by the following test (hereinafter, this test is also referred to as a “β i calculation test”). Specifically, the first and second operations are performed with a resistor having a known flow resistance coefficient, for example, an orifice having a resistance coefficient sufficiently higher than that of the catalyst layer, mounted on each catalyst reactor 2. .. Thereby, the above-mentioned inflow temperatures _Tin1 and _Tin2 and the catalyst layer temperatures T1 _{and i} and T2 _{and i} are measured in the catalyst reactor i. Further, the differential pressure before and after the orifice is measured during the first operation. It is preferable that the inflow temperature _Tin1 is matched as much as possible with the inflow temperature during normal operation. For the measurement of the differential pressure, a pressure gauge similar to each of the above-mentioned pressure gauges may be used. From this differential pressure, the flow rate distribution in the catalyst reactor i can be calculated. As described above, even if the catalyst reactor i is blocked, the differential pressure before and after the catalyst reactor i does not change significantly. However, the differential pressure can be measured by using an orifice having a sufficiently high drag coefficient as compared with the catalyst layer. The flow rate Q _i can be calculated based on this flow rate distribution and the flow rate Q _T. Then, the value of the _{model constant β i} can be determined based on the inflow temperature _{Tin 1} , _{Tin 2} , the catalyst layer temperature T _{1, i} , T _{2, i} , the flow rate Q _i , and the mathematical formula (6). The β _i thus obtained may be used in actual operation. In addition, β _i may be obtained for all catalyst reactors 2, or may be obtained only for one of the catalyst reactors 2, and this may be applied to other catalyst reactors 2. Moreover, as is clear from FIG. 3, β _i fluctuates from moment to moment during normal operation. Therefore, it is preferable to update _{β i at an arbitrary timing.}

(3-4. Fourth operation)
In the fourth operation, when the flow rate Q _i in the catalyst reactor i obtained by the above method is smaller than a predetermined value, it is determined that the catalyst reactor i is blocked. As the predetermined value, for example, a value sufficiently smaller than the initial flow rate in the catalyst reactor i immediately after filling the catalyst layer, for example, a value of 1/3 of the initial flow rate can be used. Further, the blockage determination may be performed by an operator, or the determination may be automatically performed by incorporating software encoding the above procedure into a calculator or the like.

According to the method of the first embodiment, it is possible to easily and quickly detect a catalyst reactor in which a blockage has occurred during operation with a plurality of catalyst reactors arranged in parallel.

(4. Method for clearing blockage of catalytic reactor)
When it is determined that the catalyst reactor i is blocked, the deposit removing device 3 in the catalyst layer of the catalyst reactor i is operated so as to clear the blockage of the catalyst layer. As a result, the blockage of the catalyst reactor i is eliminated and the flow rate is restored.

The first to fourth operations described above may be artificially performed by an operator, or may be performed by the blockage detection determination device 1000 shown in FIG. The blockage detection determination device 1000 has, for example, a hardware configuration such as a CPU, a ROM, a RAM, a hard disk, and a communication device. A program capable of realizing the first means to the fourth means for performing the first operation to the fourth operation is recorded in the ROM, and the CPU reads and executes this program. As a result, the first to fourth means are realized. The communication device receives the measured values transmitted from each measuring device (for example, flow meter 112, inflow pressure meter 113, etc.) provided in the heating furnace device A1. The measured value is used for calculation by the CPU. The communication device transmits various control signals generated by the CPU to each drive device (for example, a fluid switching device 110, a gas preheating device 111, a deposit removing device 3 in the catalyst layer, etc.). These drive devices are driven based on control signals. When the first to fourth operations are artificially performed, the blockage detection determination device 1000 may be omitted.

<2. Second embodiment>
Next, the second embodiment will be described. In the second embodiment, the _{method for calculating β i} in the third operation is different from that in the first embodiment. Other than this, it is the same as that of the first embodiment. Therefore, here, the third operation will be described.

In the second embodiment, the drag coefficient η _i in the catalytic reactor i is defined by the following equation (7).
η _i = ΔP / Q _i ² (7)
ΔP: Differential pressure between the inflow collecting pipe and the outflow collecting pipe

Here, the differential pressure between the inflow collecting pipe and the outflow collecting pipe, that is, the pressure loss ΔP is the difference between the measured pressure values of the inflow pressure gauge 113 and the outflow pressure gauge 116.

As described above, the present inventors have found that there is a positive correlation between the _{resistance coefficient η i} and the model constant β _i. The physical meaning of this correlation _{is that both the increase in the value of the drag coefficient η i} and the increase in the value of the model constant β _i are caused by the increase in the amount of cork deposited in the catalyst layer. Specifically, when cork is deposited in the catalyst layer, the accumulated cork substantially narrows the flow path in the catalyst layer, so that _{the value of η i} increases (for example, if it is the same in this state). If the flow rate Q _{i is} to be maintained, the pressure loss ΔP increases, so that the value of _{η i increases from Eq. (7)).}

On the other hand, the thermal conductivity of cork is generally higher than the thermal conductivity of the raw material gas, reforming gas or catalyst particles that fill the space. Therefore, when cork powder is deposited in the space between the catalyst particles in the catalyst layer, the deposited cork powder is deposited. Through this, heat is easily transferred in the catalyst layer, and the thermal conductivity of the catalyst layer is increased. The heat transmission coefficient h in the formula (1) is the heat conduction of the gas flowing in the catalyst layer on the surface of the catalyst particles, the heat conduction of the catalyst layer, the heat conduction of the outer wall of the catalyst reactor, and the outer wall of the catalyst reactor of the gas in the heating furnace. It is a coefficient showing the total heat transfer property of the above heat conduction. When any of these heat transfer elements is promoted, the value of thermal transmission rate h increases. Therefore, when the thermal conductivity of the catalyst layer increases due to the increase in the deposited cork powder, the thermal transmissivity h increases, and β _i increases from the equation (1).

Therefore, in the second embodiment, _{the relationship between the drag coefficient η i} and the model constant β _i is modeled by the following equation (8).
β _i = β _{0, i} · (η _i / η _{0, i} ) ^ai (8)
β _{0, i} : Initial value of _{β i a i} : Model constant ( _ai ≧ 0)

_{By substituting η i} in equation (7) for η _{2, i} and substituting equation (7) into equation (8), the following equation (9) is obtained.

In summary the following expression (10) obtained for Q _i this equation into Equation (6).

Therefore, in the third operation, the flow rate Qi of the catalyst reactor _i is calculated based on the mathematical formula (10). Then, the occlusion of the catalytic reactor i can be determined using the same method as in the first embodiment.

Here, the model constant ai, the initial value β _{0, i of} the model constant, and the initial value η _{0, i} of the drag coefficient are obtained in the same manner as in the βi calculation test of the first embodiment. _{That is, a test for calculating β i} in a specific catalyst reactor i is performed in a state where there is no cork deposition (a state before the start of normal operation). As a result, the initial values β _{0, i} of the model constant are calculated. Further, the initial value η _{0, i of the} resistance coefficient is also calculated from the differential pressure ΔP and the flow rate Q _i. At this time, instead of providing an orifice that increases the pressure loss, a flowmeter such as a pitot tube is temporarily installed in the catalytic reactor i, and the obtained differential pressure is measured by a precision differential pressure gauge, whereby the catalytic reactor i The flow velocity (= flow rate) within can be obtained. _{After that, a β i} calculation test is performed using the same method at any time during normal operation. As a result, the model constant β _i is calculated. Further, the resistance coefficient η _i is calculated from the differential pressure ΔP and the flow rate Q _{i when the model constant β i is calculated.} Then, the obtained values are plotted on a plane with the horizontal axis as _{the logarithmic axis of ηi / η 0, i} and the vertical axis as the logarithmic _{axis of βi / β 0, i} , and the approximate straight line of each point is the least squares method. Calculate by etc. Then, the slope of this approximate straight line may be set as the model constant ai. The model constant ai may be applied to each catalyst reactor 2, or the model constant ai calculated for any of the catalyst reactors 2 may be diverted to the other catalyst reactor 2. Since such measurement using a Pitot tube and a precision differential pressure gauge is expensive and unstable, it can be applied only to a βi calculation test for obtaining a model constant, which can limit the target catalytic reactor and measurement frequency. It is a thing. It is not economically rational to permanently install a measuring device in all catalyst reactors and perform such measurement at all times.

In the second embodiment, the following effects can be obtained. As is clear from FIG. 3, the model constant β _{i fluctuates from moment to moment.} Therefore, in the first embodiment, when the flow rate Q _{i is} to be calculated accurately, it is necessary to _{frequently update the model constant β i.} Furthermore, the model constant β _i may fluctuate depending on the operating conditions. However, it takes time to calculate the model constant β _i. On the other hand, the mathematical formula (10) is a mathematical formula in consideration of _{β i, which fluctuates from moment to moment.} Therefore, once even calculated model constants ai, it is possible to calculate the flow rate Q _i by considering the model constants beta _i varying with time after, it is possible to calculate the flow rate Q _i easier and accurate ..

<3. Third Embodiment>
In the third embodiment, using the measured value of the gas flow rate Q _T at the inflow collector pipe 101, determined more accurately estimate the gas flow rate Q _i of each catalytic reactor i. Other than this, it is the same as the first or second embodiment or the second embodiment described above.

In the third embodiment, first, a tentative estimated value of the gas flow rate in each catalyst reactor i, Q _{tmp, i,} is obtained by the same method as in the first or second embodiment. For example, in the first embodiment, the model constant β _i is set as a fixed value, and the tentative estimated values Q _{tmp, i} of the gas flow rate are calculated by the mathematical formula (6). In the second embodiment, a tentative estimate of gas flow rate, Q _{tmp, i,} is calculated by the mathematical formula (10).

From the volume balance (here, it is converted to the standard state and the change in gas composition is also ignored) _{, the total value of Q tmp and i} in all catalytic reactors should match the inflow pipe flow rate Q _T. Is. Therefore, assuming that the estimation error of the flow rate in each catalyst reactor i is a constant ratio, and introducing a fixed correction coefficient b, the following equation (11) holds.

By modifying this equation (11), b is expressed by the following equation (12).

The provisional flow rate Q _{tmp, i} in each catalyst reactor 2 is corrected by the following equation (13) to obtain _{the flow rate Q i in each catalyst reactor 2.}

Q _i = bQ _{tmp, i} (13)

That is, in the third embodiment, using equations (13) to correct the flow rate Q _i in the catalytic reactor i, on the basis of the flow rate Q _i of the corrected fourth operation, namely occlusion in the catalytic reactor i Judge the presence or absence of. Thus, compared to the case where the fourth operation with a flow rate Q _i calculated by Equation (6) or (10) directly, more accurate closed determination.

<1. Example 1>
In Example 1, a catalytic reactor 1 having seven catalytic reactors 2 (ie, N = 7) was prepared. Then, a coke oven gas containing tar as a raw material gas was supplied to each catalytic reactor i, and the reforming operation was performed under normal operating conditions in which the heating furnace temperature was maintained at about 800 ° C. After that, the supply gas is switched to nitrogen gas, which is a non-reactive gas, and nitrogen gas preheated to 800 ° C. ^{is supplied to each catalyst reactor i at a flow rate of 40 Nm 3} / h, and the temperature of the catalyst reactor i becomes constant. Held up to (first operation). The end of the first operation is defined as the "initial condition". Further, in Example 1 and Examples 2 to 4 described later, the unit of the _{model constant β i} ^{is m 3} / h. Therefore, the model constant βi of Examples 1 to 4 is a value obtained by multiplying the value (value whose unit is m ³ / s) obtained in the embodiment by 3600.

Next, the preheating temperature of the supplied nitrogen gas was lowered and held until the temperature of the catalyst reactor i became almost constant (second operation). The catalyst layer temperatures (catalyst reactor temperatures) T _{1, i} and T _{2, i} after the first operation and after the second operation are as shown in Table 1, respectively.

Then, the flow rate Q _i in each catalyst reactor i was calculated by the method described in the first embodiment. Here, the temperatures shown in Table 1 were used for each temperature, and the model constant β _i was calculated by performing a _{β i} calculation test under the condition that there was no cork deposition in the catalyst layer. The values of the model constant β _i are shown in Table 2. In addition, Table 2 shows the flow Q _i calculated at some point. If the calculation result is a negative value, the solution diverges, so Q _i = 0.

From the results of Table 2, the 7 th catalytic reactor 2, the flow rate Q _i is significantly less than the other catalytic reactor 2, it is possible to catalytic reactor 2 is judged that closed. Therefore, the blockage was released by driving the deposit removing device 3 in the catalyst layer only for the catalyst reactor 2. However, total flow rate of each catalytic reactor i calculated here, 13.1 nm ³ / h was achieved, 1/3 of the flow rate _{Q T.} Therefore, it is considered that the difference from the actual flow rate is large and the quantitativeness of the flow rate estimate of each catalyst reactor i is rather low.

<2. Example 2>
Therefore, in order to the value of the model constants beta _i reflect the impact of coke state deposition, using a fixed value determined empirically for each catalytic reactor i as a model constant beta _i, performed all other conditions Example 1 The flow rate Qi was calculated in the same manner as in the above. That is, the model constant β _i was updated every hour, and the flow rate Q _i was calculated using this model constant β _i. The results are shown in Table 3. The values in Table 3 are the model constant β _i and the flow rate Q _i at a certain point in time.

The total value of the flow rate of each catalytic reactor i is (close to the flow rate _{Q T)} of 32.7Nm ³ / h, and the improved than in Example 1. In the seventh catalytic reactor 2, the flow rate was 1/3 of the initial flow rate, so it was determined to be blocked. In addition, although the flow rate of the 4th catalyst reactor 2 was 1/3 or more of the initial flow rate, a remarkable decrease in the flow rate was observed, so that the 4th and 7th catalyst reactors 2 were in the catalyst layer. The deposit removing device 3 was driven to release the blockage.

<3. Example 3>
To correct for differences in the total value 32.7Nm ³ / h and the flow rate _Q T = 40Nm ³ / h of _{Q i} calculated in Example 2, and b = 1.22, was determined this Example 2 the correction of the flow rate Q _i by multiplying uniformly to the flow rate Q _i. The results are shown in Table 4.

In the 4th and 7th catalyst reactors 2, although the flow rate was 1/3 or more of the initial flow rate, a remarkable decrease in the flow rate was observed. The internal deposit removal device 3 was driven to release the blockage. In this embodiment, with a total flow rate Q _i is coincident with the flow rate Q _T, each Qi has become a higher relevance.

<4. Example 4>
Other calculated flow rate Q _i by using the method described in the second embodiment was subjected to the same treatment as in Example 1. Here, as a constant when giving _{Q i , β i} used in Example 1 is used for _{β 0, i,} and a value 0.42 determined in advance for the model constant ai is used as the differential pressure ΔP. Used a typical value of 38 Pa at the time of the first operation. Further, _{η i} (= η _{0, i} ) was calculated using ΔP _{and β 0, i} (Table 5). Shows the calculation results of the flow rate Q _i of this time shown in Table 5. The flow rate Q _i shown in Table 5 is a value calculated at a certain point.

In Example 2, _{it was necessary to individually investigate β i under} various operating conditions and determine a fixed value, but in this example, once a minority model constant is determined, instantaneous β _i is considered. to be able to calculate the flow rate Q _i, could be managed more efficiently operated.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical idea described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

1 Catalyst reactor 2 Catalyst reactor 3 Catalyst layer deposit removal device 10, 40 Reaction vessel 11, 41 Inflow passage 12, 42 Outflow passage 13, 43 Catalyst layer 14, 44 Catalyst cage 15 Valve seat 16 Vent hole 17 valve Body 18, 48 Manometer 21, 49 Drive 101 Inflow collecting pipe 102 Outflow collecting pipe 110 Fluid switching device 111 Gas preheating device 112 Flow meter 113 Inflow pressure meter 114 Inflow thermometer 115 Catalyst layer thermometer 116 Outflow pressure meter

Claims (9)

When a non-compressible fluid, which is a raw material fluid, is reacted and reformed in a catalyst layer which is a fixed bed in a catalyst reactor arranged in parallel in a catalyst reactor, a by-product is contained in the catalyst layer. This is a method for detecting blockage of a catalytic reactor, which detects that the catalytic reactor is blocked due to the accumulation of
The catalytic reaction device is
The catalyst reactors arranged in parallel, an inflow collecting pipe which is a collecting pipe for supplying fluid to all the catalyst reactors, and a collecting pipe for collecting the fluids flowing out from all the catalyst reactors and flowing them downstream. A furnace equipped with an outflow collecting pipe which is a collecting pipe, a catalyst layer thermometer provided in each of the catalyst layers of all the catalyst reactors, and an inflow thermometer which measures the inflow temperature which is the fluid temperature of the inflow collecting pipe. The equipment inside the heating furnace, which is located inside the heating furnace with adjustable temperature,
A fluid preheating device that preheats the fluid supplied to the inflow collecting pipe, and
A fluid switching device for switching the fluid supplied to the inflow collecting pipe between the raw material fluid and the non-reactive fluid, and
A flow meter for measuring the flow rate passing through the inflow collecting pipe is provided.
The method for detecting blockage of the catalytic reactor is
The fluid switching device is set so that the non-reactive fluid passes through all the catalytic reactors, and the fluid preheating device is adjusted so that _{the inflow thermometer shows the first inflow temperature Tin1.} first and operations for recording the inflow collecting pipe flow Q _T and each of the catalytic reactor the catalyst layer temperature T _1, which is measured by the catalyst layer thermometer _i when,
The fluid preheater is adjusted so that the inflow thermometer _{shows a second inflow temperature Tin2} different from the first inflow temperature _Tin1, and the catalyst layer thermometer of each of the catalyst reactors at that time. The second operation of recording the catalyst layer temperature T2 _{, i measured in}
In the i-th catalytic reactor
β _i = hLX _i / (ρC _p )
h: Heat transmission coefficient L: Circumferential length of piping ρ: Gas density Cp: Constant pressure specific heat of gas X _i : Length of piping in the i-th catalyst reactor _{Using β i} defined by the equation, each catalyst The third operation of calculating _{the flow rate Q i} in the reactor as a function of the _{Tin 2} , _{Tin 1} , T _{1, i} , T _{2, i} , and β _{i, and}
A catalytic reactor comprising a fourth operation of determining that the i-th catalytic reactor corresponding to the _{flow rate Q i} is blocked when the flow rate Q _i is smaller than a predetermined value. Blockage detection method. In the third operation,
Wherein _{T in2, T in1, T 1} , i, a function of _{T 2, i,} and beta _i,
Q _i = -β _i / Ln [(T _{2, i} −T _{1, i} ) / (T _in2- T _in1 )]
age,
The method for detecting blockage of a catalytic reactor according to claim 1, wherein _{β i is set to a fixed value.} The catalytic reaction device further includes a differential pressure measuring device for measuring the differential pressure between the inflow collecting pipe and the outflow collecting pipe.
In the third operation,
η _i = ΔP / Q _i ²
_{ΔP: The resistance coefficient η i} defined by the equation of the differential pressure between the inflow collecting pipe and the outflow collecting pipe,
β _i = β _{0, i} · (η _i / η _{0, i} ) ^ai
β _{0, i} : Initial value of _{β i a i} : Model constant In addition to obtaining _{β i,}
The function of the flow rate _{Q i}

The method for detecting blockage of a catalytic reactor according to claim 1, wherein the method is characterized by the above. Claims 1 to 1, characterized in that the flow rate Q _i is corrected so that the flow rate obtained by integrating the flow _{rate Q i} calculated in the third operation _{for all the catalyst reactors matches the flow rate Q T.} The method for detecting blockage of a catalytic reactor according to any one of 3. The method for detecting blockage of a catalytic reactor according to any one of claims 1 to 4, wherein the raw material fluid contains a hydrocarbon. The device in the heating furnace further includes a device for removing deposits in the catalyst layer for independently removing the deposits in the catalyst reactor for each catalyst reactor, according to claims 1 to 5. The method for detecting blockage of a catalytic reactor according to any one of the above items. When it is determined that the i-th catalyst reactor is clogged by the method for detecting the clogging of the catalyst reactor according to claim 6, the i-th catalyst reactor is eliminated so as to eliminate the clogging of the catalyst layer. A method for relieving blockage of a catalyst reactor, which comprises operating the above-mentioned catalyst layer deposit removing device. A non-compressible fluid, which is a raw material fluid, is reacted and reformed in a catalyst layer which is a fixed bed in a plurality of catalyst reactors arranged in parallel, and by-products are deposited in the catalyst layer. A catalytic reactor that detects that the catalytic reactor is blocked.
To collect the catalyst reactors arranged in parallel, the inflow collecting pipe which is a collecting pipe for supplying fluid to all the catalyst reactors, and the fluid flowing out from all the catalyst reactors and let them flow downstream. It has an outflow collecting tube, which is a collecting tube of the above, a catalyst layer thermometer provided in each of the catalyst layers of all the catalyst reactors, and an inflow thermometer for measuring the inflow temperature which is the fluid temperature of the inflow collecting tube. , The equipment in the heating furnace placed in the heating furnace where the furnace temperature can be adjusted,
A fluid preheating device that preheats the fluid supplied to the inflow collecting pipe, and
A fluid switching device for switching the fluid supplied to the inflow collecting pipe between the raw material fluid and the non-reactive fluid, and
A flow meter for measuring the flow rate passing through the inflow collecting pipe is provided.
In addition
The fluid switching device is set so that the non-reactive fluid passes through all the catalytic reactors, and the fluid preheating device is adjusted so that _{the inflow thermometer shows the first inflow temperature Tin1.} first means for recording the flow of collecting pipe flow Q _T and each of the catalytic reactor the catalyst layer temperature T _1, which is measured by the catalyst layer thermometer _i when,
The furnace temperature of the fluid preheater is adjusted so that the inflow thermometer _{shows a second inflow temperature Tin2} different from the first inflow temperature _{Tin1, and the catalyst of each of the catalytic reactors at that time.} A second means of recording the catalyst layer temperature T2 _{, i measured by the layer thermometer, and}
In the i-th catalytic reactor
β _i = hLX _i / (ρC _p )
h: Heat transmission coefficient L: Circumferential length of piping ρ: Gas density Cp: Constant pressure specific heat of gas X _i : Length of piping in the i-th catalyst reactor _{Using β i} defined by the equation, each catalyst A third means for calculating _{the flow rate Q i} in the reactor as a function of the _{Tin 2} , _{Tin 1} , T _{1, i} , T _{2, i} , and β _i.
When the flow rate Q _i is smaller than a predetermined value _{, a fourth means for determining that the i-th catalyst reactor corresponding to the flow rate Q i} is blocked, and a blockage detection determination device for the catalyst reactor to execute the operation. A catalytic reactor comprising. 8. The device in the heating furnace further comprises a device for removing deposits in the catalyst layer for independently removing the deposits in the catalyst reactor for each catalyst reactor, according to claim 8. Catalytic reactor.

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