TW201032886A - Pressure swing adsorption type gas generation device - Google Patents

Abstract

The present invention provides a pressure swing adsorption type gas generation device. When performing operation with the product gas flow less than the rated maximum output, recycling efficiency can be appropriately maintained and the amount of air consumption is reduced. For performing the control, the setting values of the stage corresponding to the status of usage is used. The pressure swing adsorption type gas generation device comprises absorption tanks 1, 2; air guide flow path 6, 7 connected to the absorption tanks; a product tank 3; exhaust flow paths from two adsorption tanks; a pressure equalizing flow path for communicating two adsorption tanks; a flow path between two adsorption tanks and the product tank; valves disposed in the flow paths; a sensor F for detecting the product gas flow rate Lp; and a control device 10 for controlling the opening and closing of each valve. The control device performs switch to the absorption tanks and controls adsorption and desorption actions repeatedly. The adsorption and desorption actions are performing adsorption by adsorbent in one of the two absorption tanks, and desorbing gas from the adsorbent in the other absorption tank. According to the ratio of the reduced output relative to the maximum output Lm with the maximum set value of the product gas flow Lp, R=Lp/Lm, the sustained time for a period of the adsorption and desorption actions, i.e. the adsorption and desorption period T, is switched stagedly, so as to control the adsorption and desorption actions.

Description

201032886 • VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a pressure swing adsorption gas generating apparatus for generating nitrogen by a pressure swing adsorption method, in particular, for a consumption of raw material air Reduced and improved energy saving effect. [Prior Art] As one of non-cryogenic techniques for producing nitrogen or oxygen, a ps A (pressure swing adsorption) method is known. According to the PSA method, for example, air is used as a reference material to adsorb oxygen in the raw material air by an adsorbent, whereby nitrogen can be separated to obtain high-purity nitrogen as a product gas. The principle of using the high pressure adsorption amount in the PSA process is greater than the low adsorption amount. That is, the continuous operation is carried out while recovering the adsorption capacity of the adsorbent by repeating adsorption desorption, which means that the adsorbent which adsorbs oxygen under high pressure desorbs oxygen at a low pressure. Therefore, in the step of PSA, two adsorption tanks filled with an adsorbent are used, in which the adsorption step is carried out under high pressure in one adsorption tank, during which, in another adsorption tank, the adsorption is carried out under low pressure. Attached steps. Thus, in order to alternately perform the adsorptive desorption step using the two adsorption tanks, the flow path of the gas which makes the raw material air from the introduction port to the product tank through the adsorption tank is switched in accordance with the step to be performed. That is, a plurality of valves are switched in a timely manner so that, for example, the raw material air is introduced into the adsorption tank for performing the adsorption step, and the nitrogen gas is taken out from the adsorption tank or the adsorption tank is exhausted from the desorption step. Running. However, in practice, for example, where a nitrogen generating device is used, the amount of nitrogen gas 5 201032886 is not necessarily fixed, and in most cases, nitrogen is used intermittently, that is, nitrogen is not used intermittently. The amount of nitrogen used also varies with time. Further, in many cases, a plurality of nitrogen gas consumption units are used in combination with one nitrogen gas generator, and the amount of use usually varies. On the other hand, the rated production amount of the nitrogen generating device ensures the purity of the nitrogen gas at the maximum amount of production, and the amount of the raw material air at this time is set as the rated production amount. The smaller the amount of nitrogen used than the maximum amount produced, the higher the purity of the nitrogen gas, but the amount of raw air used is only slightly reduced. The reason is that in order to operate at an adsorption desorption cycle having a high recovery efficiency in accordance with the maximum amount of production, the operation is performed with a smaller amount of production, and the recovery efficiency is lowered, resulting in consumption of a large amount of raw material air. Therefore, even if the amount of nitrogen used is reduced, the same operation of the raw material air is performed, and nitrogen of excess purity is supplied, thereby consuming the energy in vain. On the other hand, for example, in the patent document, the following method is disclosed: In the gas-gas generating apparatus using the PSA method, the purity of the gas is stabilized, and an appropriate raw material air corresponding to the amount of nitrogen used is used. Operate with the amount of use. According to this method, focusing on the change in the oxygen concentration at the outlet of the adsorption tower, when the oxygen concentration at the outlet reaches the set oxygen concentration, the adsorption tower is switched, so that the half cycle time is automatically changed. By this, the amount of raw material air used can be reduced, so that power consumption can be reduced. [Technical Disclosure] [Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-270953 [Draft of the Invention] Japanese Patent Application No. 201032886 However, in the nitrogen generating apparatus of the above-described prior art, based on the purity of the released nitrogen gas The half cycle time changes, and Taguchi's effect can be appropriately obtained by reducing the amount of raw material used according to the amount of nitrogen used. Further, the half-cycle time is automatically changed in accordance with a preset program in the entire region of the purity of nitrogen gas which can be generated in actual operation, so that the actual control becomes complicated and the stability of the operation is impaired. Accordingly, it is an object of the present invention to provide a pressure swing adsorption type gas generating apparatus which can maintain a predetermined recovery efficiency and reduce the amount of raw material air when operating at a flow rate of less than the maximum generated product nitrogen gas, and can be The use condition is controlled by using the set value of the phase. Means for Solving the Problem The pressure swing adsorption gas generating apparatus of the present invention includes: a first adsorption tank filled with an adsorbent and a second adsorption tank; and a raw material air introduction flow path connected to the second adsorption tank and the second adsorption tank a product tank for storing nitrogen gas separated from the raw material air in the second adsorption tank and the second adsorption tank; and an exhaust gas flow path from the first adsorption tank and the second adsorption tank; a pressure equalization flow path that communicates between the adsorption tank and the second adsorption tank; a product gas flow path between the first adsorption tank and the product tank, and between the second adsorption tank and the product tank; a valve for each flow path; a product gas flow sensor for detecting a flow rate Lp of the product gas flowing out from the product tank to the outside; and a control device for controlling opening and closing of the respective valves; the control device The two adsorption tanks are switched to repeatedly control the adsorption and desorption operation, and the adsorption and desorption operation is performed after the pressure equalization step of opening the pressure equalization flow path, and on the above 7 201032886 In one of the first adsorption tank and the second adsorption tank, # is adsorbed by the adsorbent, and the other adsorption tank is subjected to a desorption step of desorbing the gas from the adsorbent. In order to solve the above problems, the pressure swing adsorption type gas generating apparatus of the present invention is characterized in that the ratio of the generated amount R = Lp / is reduced according to the maximum generated amount Lm which is set to the maximum value of the product gas flow rate 0. Lm, the adsorption desorption cycle T is controlled as a period of time during which the adsorption desorption operation is continued, and the adsorption desorption operation is controlled in stages. The effect of the invention is based on the above-described pressure swing adsorption gas. The generating device can maintain the purity of the nitrogen gas in an appropriate range when the product gas flow rate Lp is less than the maximum production amount Lm, and switch the adsorption desorption period τ stepwise according to the product gas flow rate Lp. Maintain high recovery efficiency and reduce feed air volume. Further, since the adsorption desorption week #月T is set in stages based on the product gas flow rate Lp, the set value can be easily changed in accordance with the use condition, and the energy-saving operation can be efficiently performed. [Embodiment] The present invention can adopt the following configuration based on the above configuration. In other words, the pressure swing adsorption type gas generating apparatus of the present invention may be configured such that the Hb step includes a tb rate setting unit that sets a plurality of generation ratios (steps) for the generation amount ratio R in stages. a set input value of =0 to η; η is a positive integer); and a period 201032886 setting unit for the adsorption desorption period τ for phase-adjusting the adsorption corresponding to each of the above-described generation ratios Ri The set input value of the cycle I is maintained; the control device is based on the flow rate Lp of the product gas detected by the product gas flow sense device, and the respective adsorption desorption cycle τ according to the above-described production amount ratio Ri The adsorption desorption operation T is controlled by the above-described adsorption desorption cycle T selected in the correspondence relationship. Further, the above-described production amount ratio center and the value of the adsorption desorption period are set according to the following conditions, and R〇=〇, Rn=1, 00<i<n, 〇<Ri< 1 (where Ri < Ri+i ), and

Ti>Ti+1; When the above-mentioned control device selects the above-described adsorption desorption (R = Lp / Lm) according to the following formula (1), T = Ti (1).

Further, the above-mentioned adsorption desorption cycle Τ is preferably set so that the desired nitrogen purity can be maintained at the production amount ratio R = Lp / Lm = R ^ '. 1 The main von has three tanks for storing and supplying the raw material air, compressing the air to supply the air to the upper compressor, and the air to the raw material air tank. The pressure Ρ (Η 检测 ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” ” The above detection force Ρ 01 is maintained at the predetermined combination and the upper reference value is at the time of the clearing, 'preferably set the lower reference value Ptl 201032886

Pth (Ptl < Pth) 'The above control means is controlled such that, in the process of driving the compressor to raise the detected pressure P01, the compressor is stopped when P01 g Pth; the detection is stopped when the compressor is stopped During the process of decreasing the pressure ρ〇ι, the compressor is started to drive when P01 g PU. Hereinafter, the pressure swing adsorption gas generating apparatus according to the embodiment of the present invention will be described in detail with reference to the drawings. (Embodiment 1) Fig. 1 is a schematic view showing the configuration of a nitrogen generating device according to Embodiment 1 of the present invention. The apparatus includes a first adsorption tank 1 ❹ and a second adsorption tank 2 filled with an oxygen adsorbent as a gas generating unit, and a product tank 3 for temporarily storing the generated product gas, that is, nitrogen gas, and supplying the nitrogen gas to the outside. . Further, a raw material air inlet 4 for supplying the raw material air to the gas generating unit, and a product gas outlet 5 for supplying the nitrogen gas from the product tank 3 to the outside are provided. The first adsorption valve (SV1), the second adsorption valve (SV2), the first exhaust valve (SV3), and the second row are provided in the pipes 6 and 7 that connect the first adsorption tank 1 and the second adsorption tank 2. A gas valve (sV4), two pressure equalizing valves (SV5), a first outlet valve (SV6), a second outlet valve (SV7), and a flow regulating valve 8. The raw material air is introduced into the first adsorption valve (SV1) and the second adsorption valve (SV2) in each gas generation unit. The first adsorption valve (SV1) is connected to the first adsorption tank 1 by a pipe 6, and the second adsorption valve (SV2) is connected to the second adsorption tank 2 by a pipe 7. The flow paths indicated by the pipes 6 and the pipes 7 are connected to the exhaust port 9 via the first exhaust valve (SV3) and the second exhaust valve (SV4), respectively, 10 201032886. The first adsorption tank 1 and the second adsorption tank 2 can communicate via two equalizing valves (SV5) provided above and below. One of the three pipes led out from the first adsorption tank 1 is connected to the product tank 3 via the first outlet valve (SV6). One of the three pipes derived from the second adsorption tank 2 is connected to the product tank 3 via the second outlet valve (SV7). The first adsorption tank 1 and the second adsorption tank 2 are connected to each other via the flow rate adjusting valve 8

A raw material air pressure sensor P is disposed in the line connected to the raw material air inlet 4. The first adsorption tank pressure sensor P1 and the second adsorption tank pressure sensor P2 are provided in each of the first adsorption tank 1 and the second adsorption tank 2. A product tank pressure sensor P3 for detecting the pressure in the tank is provided in the product tank 3. In the flow path from the product tank 3 to the product gas outlet 5, a product gas flow sensor F for detecting the flow rate of the product gas flowing out of the product tank 3, and a pair of purity sensors as the product gas flowing out are provided. The oxygen concentration sensor OC for detecting the oxygen concentration in the product gas. In addition, in the following description, the pressure values detected by the raw material air pressure sensor P〇, the first adsorption tank pressure sensor P1, the second adsorption tank pressure sensor p2, and the product (four) force sensor P3 are It is represented by the corresponding symbols po, pi, P2, and P3. The output of each inductor is input to the control device 1A. Further, the opening and closing operations of the respective turns are controlled by the valve drive signal supplied from the control unit 10. The control device 10 sets various set values by the normal operation of the CPU f, η C Central Processing Unit, and the central processing unit, and performs valve drive control and operation control based on the rotation of each sensor. , the illustration related to the electric 11 201032886 = line is omitted. Fig. 1 shows a cycle control unit 1 1 and an upper cycle setting unit 13 for holding the powers unique to the present embodiment as elements included in the control device 10, and further indicates that it is useful for performing the corresponding elements of the μ 4 element. The touch panel 14 is operated. Referring to Fig. 1 and Fig. 2, the gas generating device 2 of the above configuration is used. In the first adsorption tank 1 and the second adsorption tank 2, the adsorption operation (supplying the compressed raw material air and sucking it under pressure at high pressure) and the desorption operation (decrease the pressure) The gas desorbed by the adsorption" is alternately performed by switching between the respective rooms. In the following description, the step of performing the adsorption operation in the i-th adsorption tank i and performing the desorption operation in the second absorption is referred to as the A step, and the adsorption operation is performed in the second adsorption unit in the first adsorption tank. The step of performing the desorption operation in ι is referred to as the B step, and the step of equalizing the pressure of the two adsorption tanks is referred to as the c step (or referred to as the pressure equalization step). In steps A and B The c step is inserted between the two steps, and the steps A and B are alternately performed, and the operation of taking out nitrogen or oxygen is continuously performed. Fig. 4 shows that the first adsorption tank i is an adsorption step and the second adsorption tank 2 is The state of the desorption step, that is, the step A, is basically the same as the well-known step. Therefore, the steps of the steps B and c are omitted, and the piping is indicated by a thick line. The part refers to the state in which the gas flows. In the figure, the hatching added to the valve indicates the open state, and the valve without the hatching is in the closed state. Further, it is applied to each of the adsorption tanks 1, 2 and the product tank 3. The hatching indicates the presence of nitrogen. Figure 2 Pressure distribution and operation timing in each step of each step. 12 201032886 The curve shown by P0 in Fig. 2 indicates the raw material air pressure supplied to the first adsorption valve (svi) and the second adsorption valve (SV2). ρι to ρ3 indicate The pressure values obtained by the first adsorption tank pressure sensor P1, the second adsorption tank pressure sensor P2, and the product tank pressure sensor P3. svi, SV2, SV3, SV4, SV5, SV6, and SV7 are respectively used to make Corresponding valve opening and closing valve drive signal. In the area where hatching is added, each valve is open due to the valve drive signal, and in other areas, each valve is closed. The horizontal axis in the graph does not show time. In the direction of the time axis, the steps are repeated in the order of c step, A step, C step, B step, and C step. The time of the upper part of the symbol of A to c is the duration of each step. In the second step A, the drive signal supplied to the first adsorption valve (SV1), the second exhaust valve (SV4), and the i-th outlet (SV6) is an open signal, and the closed signal is supplied to the other. Valve. Pressurized material in the second adsorption tank i The gas is introduced into the bottom of the j-th adsorption tank and the adsorption step is performed. As the raw material air pressure p〇 increases, the pressure of the i-th adsorption tank ρι φ also rises. Accordingly, oxygen is adsorbed from the raw material air by the oxygen adsorbent, and the nitrogen gas is self-adsorbed. The upper part of the tank flows out and is led to the product tank 3 via the U-valve (SV6). Accordingly, the product tank pressure P3 rises. The star is decompressed by the second exhaust valve (SV4). The second adsorption tank pressure P2 is rapidly decreased. At this time, the circulating nitrogen taken out from the top of the first adsorption tank 1 via the flow rate adjusting valve 8 is introduced into the top of the second adsorption tank 2. By the action 'oxygen self The oxygen adsorbent is desorbed and discharged. In the pressure equalizing step of step c, the pressure equalizing valve (sv5) is opened, and the other shoulders are closed. Therefore, the raw material gas pressure PG rises to the pressure supplied from the raw material air inlet 13 201032886 4 . The pressure of the first adsorption tank ρι decreases, and the pressure of the second adsorption tank P2 rises, and the pressures of the two adsorption tanks become equal. The purpose of performing the pressure equalization step is to reduce the energy loss caused by the release of pressurized gas to the atmosphere when the self-adsorption step enters the desorption step. That is, the pressure of the tank entering the desorption step is supplied to the tank entering the adsorption step, thereby recovering about half of the pressurized energy. In step B, the desorption step is performed in the first adsorption tank, and the adsorption step is performed in the second adsorption tank 2. The operation at this time is symmetrical with the operation in the step A, and the operation system in the first adsorption tank i and the second adsorption tank 2 is opposite to the step A. That is, in step B, the open signal is supplied to the second adsorption valve (SV2), the first exhaust valve (SV3), and the second outlet valve (sv7), and the closing signal is supplied to the other valves, and the rest is Step A performs the same operation, and thus the detailed description is omitted. As described above, the adsorption step and the desorption step of the inclusion pressure equalization step are alternately performed in the first adsorption tank 丨 and the second adsorption tank 2, whereby nitrogen gas is continuously generated. Thus, the period of the adsorption desorption operation which is accompanied by the pressure equalization C step and one of the steps A or B is continued, and is defined as the adsorption desorption period T. The nitrogen generating device in the present embodiment is configured to change the adsorption/desorption cycle T in accordance with the state of use of the generated nitrogen gas. Here, the state of use of nitrogen is represented by the product gas flow rate Lp, which is obtained by detecting the flow rate of the product gas flowing out of the product tank 3 by the flow sensor f. Further, the maximum generated amount Lm set to the maximum value of the product gas 々U·the amount Lp is defined as the rated generation amount. 14 201032886 The reduced production ratio R with respect to the maximum generated amount Lm is defined as R = Lp / Lm. In the present embodiment, when the operation is performed at a product gas flow rate Lp smaller than the maximum (rated) generation amount, the adsorption desorption period τ is made according to the generation amount ratio R = Lp / Lm by maintaining the purity of the nitrogen gas within a predetermined range. The stage is switched to control the adsorption desorption time which maintains high recovery efficiency and reduces the amount of raw material air. Hereinafter, a specific example of the adsorption desorption time control will be described. First, the ratio setting unit 12 of FIG. 1 holds a setting input of a plurality of generation amount ratios Ri=Li/Lm (i=〇~η; η is a positive integer) which are set in stages for the generation amount ratio R. value. The ratio of the amount of production R is a ratio of the result of the decrease with respect to the maximum amount of production Lm, and therefore, the ruler 丨. Further, the period setting unit 13 holds the set input value for the adsorption desorption period Ti which is set in stages for each of the generation amount ratios & These settings are entered and set by the operation of the touch panel 14. The reference period control unit 11 corresponds to the flow rate Lp of the product gas (production amount ratio R=LP/Lm), and the respective generation amount ratios Ri held by the ratio setting unit 12 and the period setting unit 13 are maintained as π a 卞 之 附 附 附 附 来 来 来 来 来 来 来 来 来 来 来 来 来 来 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱 钱The above-mentioned set value used for the profit γ in the above control is adjusted according to the following conditions. R〇=0, Rn=l, and 00<the range of the heart is '〇<Ri<1 (where 'MU, and 15 201032886

Ti> Ti+1 again selects the adsorption desorption period τ according to the following (number i). When RN1 < ( R = Lp / Lm) $ Ri, Τ = Ί \ ( ι ) and, when the production ratio R = Lp / Lm = Ri, preferably in a manner to maintain the desired product gas purity The adsorption desorption period Ti is set. Fig. 3 is a table showing the form of the flow rate running red type which is the basis of the adsorption desorption time control as described above. Stepi to STEP5, which are arranged side by side in the longitudinal direction, indicate a section corresponding to each set value of the generation amount ratio Ri. The ratio of the amount of production Ri (%% to ® 100%) expressed in percentage, the adsorption desorption period Ti (second), and the set flow rate are shown in each section. In this example, n=5. For example, in STEP 1, the 1=5 ′ generation amount ratio r5 is 1〇〇%. Therefore, the set flow rate 1 〇〇〇 Nm3/h described in the set flow rate display is the rated generation amount, that is, the maximum generation amount Lm. In this section, the adsorption desorption period D5 is 60.0 seconds, which corresponds to the lower limit of the adsorption desorption period τ.

Further, the STEP2 system i=4 ’ generation amount ratio ι is 75%, and the set flow rate is set to 75.0 NmVh. In this section, " and the desorption cycle T4 is 90.0 seconds. According to the above (number!), at R4< (R=Lp/Lm) $

In the range of Rn, i.e., in the range where the amount-of-production ratio R exceeds 75% and is 100% or less, the adsorption-desorption period τ is selected to be 6 〇 〇. Similarly, in the range where the production amount ratio R exceeds 50% and is 75% or less, the adsorption desorption period Τ is selected to be 90.0 seconds. In the range where the production amount ratio _ R exceeds 25 〇 / 〇 and is 5 % or less, the adsorption desorption period τ is selected to be 12 〇 〇. In the range where the production amount ratio R exceeds G% and is 25% or less, the adsorption desorption week 16 is selected as 150.0 seconds. As described above, the nitrogen gas generating apparatus according to the present embodiment performs the adsorption desorption time according to the product gas flow rate Lp by operating the product gas flow rate Lp smaller than the maximum production amount Lm. Switching in stages ensures high recovery efficiency while reducing the amount of feed air. The section where the amount ratio Ri is generated and the corresponding adsorption desorption period Ti can be changed by the set value, so that the energy-saving operation can be realized in an optimum state according to the situation at the time of practical use. Fig. 4 and Fig. 5 show the effects produced by using the nitrogen gas generating apparatus of the present embodiment. Fig. 4 shows the value obtained by comparing the raw material air consumption rate in the case of the "pre-operation" in which the adsorption/desorption cycle τ is fixed and the operation in the embodiment based on the setting shown in Fig. 3. Fig. 5 is a diagram showing the table of Fig. 4 in a graph form. (Embodiment 2) FIG. 6 is a schematic view showing a configuration of a nitrogen gas generator according to Embodiment 2 of the present invention. This device basically has the same configuration as the device of the embodiment i shown in Fig. 1. Therefore, the same elements are denoted by the same reference numerals and the description of the repetition is simplified. In the apparatus of the first embodiment, the raw material air supplied from the outside of the gas generating device is received. In the present embodiment, the air introduced from the raw material air inlet 4 and passing through the air filter 15 is used by the compressor. After being compressed (for example, using an oil-free scroll compressor), it is supplied as raw material air. Compressed by the compressor 16 'The raw material air is temporarily stored in the raw material 17 201032886 after the empty rolling tank 17 is supplied to the first adsorption tank 1 or the second adsorption tank 2 . The raw material air tank 17 is provided with a raw material air pressure sensor ροι for detecting the pressure in the tank. The pressure value detected by the raw material air pressure sensor P01 is indicated by the same symbol ροι. A compressor drive control unit 18 is provided in the control device 1 . The compressor drive control unit 18 selects the drive pressure and the stop of the compressor 16 based on the magnitude of the detected pressure p 〇 1 of the material air pressure sensor p 〇 1 to perform control (start stop control). That is, the compressor 16 is driven when the detected pressure P 〇 1 is P01 < Pt with respect to the predetermined reference value Pt, and the compressor 16 is stopped when p 〇 igpt 〇. However, in order to ensure the stability of the operation, the control corresponding to the process of detecting the magic P01 is performed. That is, the lower reference value Ptl and the upper reference value Pth (Ptl < Pth) are set. Then, in the process of driving the compressor i 6 to raise the detection pressure P01, the compressor 16 is stopped when p 〇丨 2 pth. On the other hand, in the process of stopping the compressor 丨6 and reducing the detected pressure P01, the compressor 16 is started to be driven when P 〇 1 $ Ptl. By this, it is avoided to frequently start and stop the compressor 16. The lower reference value pu © and the upper reference value Pth are set to, for example, 〇 75 MP and 0.85 MP, respectively. In this manner, the built-in compressor 16 is started and stopped based on the pressure p 〇 1 of the material air tank 17, whereby the power consumption of the compressor 16 can be reduced. Moreover, the life of the compressor 16 can be greatly extended. As described above, the power consumption can be effectively reduced by the start-stop control of the compressor 16. As in the first embodiment, it is necessary to reduce the adsorption/desorption cycle T to reduce the material air consumption rate. . 18 201032886 That is, the flow rate from the raw material air tank 17 is changed according to the product air which is compressed by the product gas. The right product gas 湳 is less than the flow from the raw material air tank 17 U Lp is less than the flow rate from the outlet. Here, if the & Ψ aim i of the transfer groove 17 of the compressor 16 is continuously operated, the pressure of the raw material air tank 17 is even when the flow rate from the raw material air price is less than ΡΛ1 f1 pf 圯P01 has reached the required level and the compressor 16 will be driven in vain. to

In this case, even if the compressor 16 is stopped at the time of POlgPt as described above, it will not be correct! The adsorption desorption operation in the adsorption tank i and the second adsorption tank 2 affects. Therefore, if the compressor 16 is stopped, the power consumption can be reduced. Further, by adopting a configuration in which the adsorption desorption cycle τ is changed to reduce the raw material air consumption rate, the stop time of the compressor 16 can be lengthened, and the power consumption can be more effectively reduced. Fig. 7 shows an effect of reducing the power consumption of the compressor by using the nitrogen gas generating apparatus of the present embodiment. As can be seen from Fig. 7, when the compressor is started and stopped by the present embodiment, compared with the case where the compressor is continuously operated by the conventional standard operation method, it can be remarkably reduced according to the amount of released air. Small power consumption. INDUSTRIAL APPLICABILITY According to the pressure swing adsorption type gas generating apparatus of the present invention, power consumption can be reduced in accordance with the increase or decrease of the flow rate of the consumed product gas, so that it can be effectively used as a system for supplying nitrogen gas. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a pressure swing adsorption type nitrogen gas 19 201032886 generating apparatus according to a first embodiment of the present invention. Fig. 2 is a view showing a pressure change and an operation timing in the operation of the nitrogen generating device of Fig. 2;

Fig. 3 is a table showing the setting of the flow rate operation program which is the basis of the adsorption/desorption control in the above-described nitrogen gas generator. B Fig. 4 is a table showing the effect of generating the gas consumption rate by using the above nitrogen gas. The illusion of the illusion of the illusion is shown in the diagram of the effect of Fig. 4: The summary of the invention is shown in the second embodiment of the invention: the adsorption type "❹ diagram of the effect of power consumption. 1 Description of the main components] 1 1st adsorption tank 2 2nd adsorption tank 3 Product tank 4 Raw material air inlet 5 Product gas outlet 6, 7 Piping 8 Flow control valve 9 Exhaust port 1〇 Control device 11 Cycle control unit 12 Ratio setting unit is indicated by use The above nitrogen generating device reduces the compressor 20 201032886

13 Cycle setting unit 14 Touch panel 15 Air filter 16 Compressor 17 Raw material air tank 18 Compressor drive control unit P0, P01 Raw material air pressure sensor PI 1st adsorption tank pressure sensor P2 2nd adsorption tank pressure sensor P3 Product tank pressure sensor F Product gas flow sensor OC Oxygen concentration sensor SV1 1st adsorption valve SV2 2nd adsorption valve SV3 1st exhaust valve SV4 2nd exhaust valve SV5 Pressure equalization valve SV6 1st outlet valve SV7 2nd σ valve 21

Claims (1)

201032886 VII. Patent application scope: i A pressure swing adsorption gas generating device, comprising: a first adsorption tank filled with an adsorbent and a second adsorption tank; and a raw material air connected to the second adsorption tank and the second adsorption tank a product flow channel for storing nitrogen gas separated from the raw material air in the first adsorption tank and the second adsorption tank; and an exhaust gas flow path from the first adsorption tank and the second adsorption tank; a pressure equalization flow path that communicates between the first adsorption tank and the second adsorption tank; © a product gas flow between the first adsorption tank and the product tank, and between the second adsorption tank and the product tank a valve disposed in each of the flow paths; a product gas flow sensor for detecting a flow rate Lp of the product gas flowing out from the product tank; and a control device for controlling opening and closing of the respective valves; In the apparatus, the adsorption and desorption operation is repeatedly controlled by switching the two adsorption tanks, and the adsorption and desorption operation is performed after the pressure equalization step of the pressure equalization flow passage opening, and the second adsorption adsorption tank and the second adsorption tank Suck In one of the tanks, the adsorption step is performed by the adsorbent, and in the other adsorption tank, a desorption step of desorbing the gas from the adsorbent is performed, and the pressure swing adsorption type gas generating device is characterized by: The reduced production ratio R = Lp / Lm set to the maximum amount of production Lm of the maximum value of the product gas flow rate Lp, and the adsorption desorption period as a period of one cycle of the adsorption desorption operation τ proceeds to 22 201032886 to switch in stages to control the adsorption desorption operation. 2) The pressure swing adsorption type gas generating apparatus of the first aspect of the invention, further comprising: a ratio setting unit for setting a plurality of production amount ratios Ri=Li for the production amount ratio R in stages a set input value of /Lm(i=〇~η; η is a positive integer) is maintained; and a period setting unit for phase-corresponding to each of the observed yield ratios Ri for the adsorption desorption period τ The set input value of the set adsorption desorption period Ti is maintained; and the control device is based on the flow rate Lp of the calyx milk detected by the product gas flow sensor, and according to the ratio of the production amount Ri The adsorption desorption cycle is controlled by the adsorption desorption cycle τ selected in the corresponding relationship. 3. For example, the value of the pressure swing adsorption gas generating device and the value of the adsorption desorption cycle Ti are set according to the yield ratio Ri and the following conditions: 0<i<n In the range, 〇 <Ri<1 (where & R〇=0, H, 0 < i Ti>Ti+1; period T: the control device selects the adsorption according to the following formula (1) Desorption week When U1<(R=Lp/Lm) SRi, when the third item of the patent application is g Ri, T=Ti ( 1 ). The pressure swing adsorption gas generating device 23 201032886, wherein: the adsorption desorption period Ti is set to maintain the desired nitrogen purity when the amount ratio R = Li) / Lm = Ri. 5. The pressure swing adsorption gas generating apparatus according to claim 2, comprising: a raw material air tank for storing and supplying the raw material air; a compressor for compressing air and supplying the raw material air tank; and a raw material air pressure sensor for detecting a pressure P01 in the raw material air tank; the control device performs control to repeatedly drive and stop the compressor according to the detection pressure P01 of the raw material air pressure sensor This maintains the detected pressure P0 1 above a predetermined value. 6. The pressure swing adsorption gas generating apparatus according to claim 5, wherein: the lower reference value Ptl and the upper reference value Pth (Ptl < Pth) are set, and the control device performs control such that When the compressor is driven to move and the detection pressure P01 is raised, the compressor is stopped when P01^Pth; during the process of stopping the compressor to decrease the detection pressure P01, the compressor is started to be driven when P01 S Ptl . Eight, the pattern: (such as the next page) 24