Gas concentration and separation equipment

Abstract

The utility model relates to gas concentration and separation equipment, which solves the problem of potential safety hazard caused by high pressure adopted by the existing purification equipment. The system comprises a pressure swing adsorption system composed of a plurality of pressure swing adsorption units, and the pressure swing adsorption units are connected in parallel. The system further comprises a mixing device, and the raw gas and the gas passing through the pressure swing adsorption system are mixed in the mixing device. Compared with the prior art, the device disclosed by the utility model has the beneficial effects that potential safety hazards can be well eliminated by adopting a low-pressure technology, the overall purification efficiency is increased, the cost of the equipment is reduced, and the energy consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of gas purification, in particular to a gas concentration and separation device. Background Technique

[0002] The gas concentration in the mine is 5-6%, the pure gas extraction volume is 9 m³ / min, and the mixed gas extraction volume is 180 m³ / min. It is necessary to increase the gas concentration to more than 8% to meet the requirements of gas power generation.

[0003] The application number is 202022899874.9, and the name is a gas purification device for coal mine exploitation. It includes a high-pressure separation box, a dust removal fan, and a gas collection tank. The dust removal fan is connected to the high-pressure separation box through an air suction pipe. A separation mechanism is provided in the high-pressure separation box. A reflux mechanism is provided at the top of the high-pressure separation box. The reflux mechanism is connected to the bottom of the high-pressure separation box through a reflux pipe. It collects gas through a dust removal fan. The air soluble in water mixed in the collected gas is dissolved in water under the pressure of the high-pressure separation box. The oxygen mixed in the gas is absorbed by a deoxidizer, so that the purity of gas collection can be greatly improved. The air in the pure water can be volatilized by the stirring rod provided in the reflux mechanism, and the stirred pure water can flow back into the high-pressure separation box through a bent pipe, so that the pure water can be reused.

[0004] However, the above patent has deficiencies: it needs to use a high-pressure separation box, and safety hazards are likely to occur under high-pressure conditions, and this purification method is not very efficient. Content of the Utility Model

[0005] In view of the above situation, in order to overcome the defects of the prior art, the utility model provides a gas concentration and separation device, which solves the problem of safety hazards existing in the current purification equipment using high pressure.

[0006] The utility model solves the technical problem through the following technical means. A gas concentration and separation device includes a pressure swing adsorption system composed of multiple pressure swing adsorption units, and multiple pressure swing adsorption units are connected in parallel;

[0007] It further includes a blending device, and the raw gas and the gas passing through the pressure swing adsorption system are mixed in the blending device.

[0008] Preferably, the pressure swing adsorption unit includes an adsorption tower filled with an adsorbent. The raw gas enters from the lower end of the adsorption tower and is discharged from the upper end of the adsorption tower after being adsorbed by the adsorbent.

[0009] Preferably, a gas extraction pump is connected to the lower end of the adsorption tower. The gas extraction pump sends the extracted gas into the adsorption tower, and the output pressure of the gas extraction pump is slightly positive pressure, and the slightly positive pressure is less than 15 KPa.

[0010] Preferably, a vacuum pump is connected to the lower end of the adsorption tower. The vacuum pump provides negative pressure to the adsorption tower, causing the gas adsorbed by the adsorbent to desorb and be discharged from the vacuum pump.

[0011] Preferably, the blending device includes a mixing box. The upper end of the mixing box is provided with a first air inlet and a second air inlet, and the lower end of the mixing box is provided with an exhaust port. The mixed gas is discharged from the exhaust port.

[0012] Preferably, a flow guiding device is arranged in the mixing box. The flow guiding device includes sequentially arranged flow guiding units. Each flow guiding unit includes two closely attached flow guiding boxes, and the air inlet directions of adjacent two groups of flow guiding boxes are different.

[0013] Preferably, the cross-sectional area of the air inlet of the flow guiding box is less than half of the cross-sectional area of the air outlet of the flow guiding box.

[0014] Preferably, the cross-sectional area of the air outlet of the flow guiding box is approximately equal to the cross-sectional area of the guiding box.

[0015] Preferably, multiple groups of vertical plates are fixed in the flow guiding box. The vertical plates are inclined, dividing the flow guiding channel into multiple independent flow guiding channels. The cross-sectional area of the flow guiding channels at the outlet gradually decreases in the direction close to the air inlet.

[0016] Compared with the prior art, the present utility model has the following advantages: 1) The low-pressure technology adopted by this device can well eliminate potential safety hazards; 2) The overall purification efficiency is increased; 3) The cost of the equipment is reduced and the energy consumption is decreased. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings are used to provide a further understanding of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model, and do not constitute a limitation to the present utility model. In the drawings:

[0018] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0019] Figure 2 is a schematic diagram of the adsorption stage of the pressure swing adsorption unit of the present utility model;

[0020] Figure 3 is a schematic diagram of the desorption stage of the pressure swing adsorption unit of the present utility model;

[0021] Figure 4 is a schematic diagram of the blending structure of the present utility model;

[0022] Figure 5 is a schematic diagram of the structure of the flow guiding device of the present utility model;

[0023] Figure 6 is a schematic diagram of the structure of a single flow guiding unit of the present utility model;

[0024] Figure 7 This is a schematic diagram of the structure of the guide box of the utility model after being cut open;

[0025] In the figure: 1. pressure swing adsorption unit; 2. mixing device; 3. adsorption tower; 4. adsorbent; 5. gas extraction pump; 6. vacuum pump; 7. mixing box; 8. first air inlet; 9. second air inlet; 10. exhaust port; 11. guide unit; 12. guide box; 13. vertical plate. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1-7 The specific implementation modes of the present utility model are further described in detail.

[0027] like Figure 1-7 As shown, a gas concentration and separation device includes a pressure swing adsorption system composed of a plurality of pressure swing adsorption units 1, wherein the plurality of pressure swing adsorption units 1 are connected in parallel;

[0028] It also includes a mixing device 2, in which the original gas and the gas that has passed through the pressure swing adsorption system are mixed.

[0029] The O2 concentration in the gas produced by the pressure swing adsorption system is low. In order to meet the O2 concentration requirements of gas power generation, the raw gas and the output gas are mixed to increase the O2 concentration. According to the gas concentration in the mine, the calculation and analysis show that 128m³ / min of the gas extraction volume in this mine is used for pressure swing adsorption concentration, and after concentration, 60m³ / min of gas with a CH4 concentration of 10.6% is produced; the remaining 52m³ / min is used for blending, and after blending, the CH4 concentration is 8.04% and the O2 concentration is 12%.

[0030] In this device, the two gases are mixed in the blending device 2 to obtain the gas with the concentration we ultimately need.

[0031] When treating a gas volume of 128 m³ / min, six pressure swing adsorption units are required1.

[0032] The pressure swing adsorption unit 1 comprises an adsorption tower 3 , which is filled with an adsorbent 4 . The raw gas enters from the lower end of the adsorption tower 3 and is discharged from the upper end of the adsorption tower 3 after being adsorbed by the adsorbent 4 .

[0033] The adsorbent 4 may be any existing one, and the adsorption and desorption functions of the adsorbent may be utilized.

[0034] Each pressure swing adsorption unit 1 includes two adsorption towers 3 with a diameter of 2m and a height of 2m. The gas output of a single system is 10m³ / min, the CH4 concentration is 10.6%, and the O2 concentration is 5%.

[0035] This technology utilizes the adsorption kinetic characteristics that the adsorption rates of O2 and N2 in the pores of the adsorbent 4 are greater than that of CH4, preferentially adsorbing O2 / N2, so that CH4 is enriched in the free space of the adsorption tower 3.

[0036] The lower end of the adsorption tower 3 is connected to a gas drainage pump 5. The gas drainage pump 5 sends the collected gas into the adsorption tower 3. The pressure output by the gas drainage pump 5 is slightly positive pressure, and the slightly positive pressure is less than 15 KPa.

[0037] The lower end of the adsorption tower 3 is connected to a vacuum pump 6. The vacuum pump 6 provides negative pressure to the adsorption tower 3, so that the gas adsorbed by the adsorbent 4 is desorbed and discharged from the vacuum pump 6.

[0038] The adsorption pressure is slightly positive pressure (<15 KPa). In the slightly positive pressure adsorption stage, the high-concentration CH4 product gas is directly produced from the top of the tower. In the vacuum desorption stage, O2 and N2 are desorbed, regenerating the adsorbent 4, so as to prepare for the next adsorption gas production process.

[0039] The mixing device 2 includes a mixing box 7. The upper end of the mixing box 7 is provided with a first air inlet 8 and a second air inlet 9. The lower end of the mixing box 7 is provided with an exhaust port 10. The mixed gas is discharged from the exhaust port 10.

[0040] In this device, the mixing box 7 can be a box-shaped mixing chamber. The original gas and the gas after adsorption are respectively introduced into the mixing box 7 through the first air inlet 8 and the second air inlet 9. The two gases are mixed in the mixing box 7 and then discharged from the exhaust port 10, so as to obtain the gas with the desired concentration.

[0041] A flow guiding device is arranged in the mixing box 7. The flow guiding device includes flow guiding units 11 arranged in sequence. Each flow guiding unit 11 includes two sets of closely attached flow guiding boxes 12, and the intake directions of adjacent two sets of flow guiding boxes 12 are different.

[0042] In this device, the first air inlet 8 and the second air inlet 9 are respectively divided into multiple pipes, so as to enter different flow guiding units 11. Adjacent flow guiding boxes 12 are respectively communicated with the first air inlet 8 and the second air inlet 9.

[0043] The cross-sectional area of the air inlet of the flow guiding box 12 is less than half of the cross-sectional area of the air outlet of the flow guiding box 12.

[0044] As Figure 7 shown, the air inlet is communicated with an intake buffer channel, and the cross-sectional area of the intake buffer channel is almost equal to half of the cross-sectional area of the air outlet of the flow guiding box 12.

[0045] The cross-sectional area of the air outlet of the flow guiding box 12 is approximately equal to the cross-sectional area of the guiding box.

[0046] An air outlet buffer channel is provided at the air outlet of the diversion box 12. The cross-sectional area of the air outlet buffer channel is almost equivalent to that of the guide box, so that the gas entering the first air inlet 8 or the second air inlet 9 can fully cover the mixing box 7.

[0047] In addition, the gases entering the diversion box 12 from the first air inlet 8 are distributed alternately, so as to ensure the rapid mixing of the two gases.

[0048] A plurality of vertical plates 13 are fixed in the diversion box 12. The vertical plates 13 are inclined, dividing the diversion channel into a plurality of independent diversion channels. The cross-sectional area of the diversion channels at the outlet gradually decreases towards the air inlet.

[0049] As Figure 7 shown, in the direction of the air inlet of the diversion channel, the cross-sectional areas are almost equal, and the outlets of the diversion channels gradually become larger towards the air inlet. This can ensure that the speeds of the gases in different diversion channels are almost the same when flowing out of the diversion channels, so as to ensure the mixing efficiency of the entire mixing box 7.

[0050] Estimation of fixed costs:

[0051] Material cost of adsorbent 4: Each pressure swing adsorption system needs to be filled with 48 t of adsorbent 4. A total of 6 systems need to be filled with 48 t of adsorbent 4 material. The unit price of adsorbent 4 is 70,000 yuan / t, so the cost of adsorbent 4 is 3.36 million yuan.

[0052] Cost of pressure swing adsorption device: Each pressure swing adsorption device includes 2 adsorption towers with a diameter and height of 2 m, 10 program control valves, a liquid ring vacuum pump with a gas volume of 10 m3 / min, a PLC control system, etc. The unit price is 150,000 yuan, so the total price of 6 systems is 900,000 yuan.

[0053] Other auxiliary devices: including drying system, flowmeter, concentration sensor, pressure sensor, blending device, etc., with a total price of about 300,000 yuan.

[0054] The total fixed cost is 4.56 million yuan.

[0055] The operating energy consumption for the system to concentrate 1 m3 of methane in terms of pure methane is 0.5 kWh / m³, and the total operating power is about 200 kW.

[0056] The pure amount of mine gas in this mine is 9 m3 / min. Calculated according to the power generation efficiency of 25%, the power generation power can reach 1350 kW. After deducting the power consumption of the pressure swing adsorption system of 200 kW, the net power generation power is 1150 kW, and the annual power generation is 10.07 million kwh. The power generation price of mine gas is 0.5 yuan / kWh, so the annual income is about 5 million yuan.

[0057] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A gas concentration and separation device, characterized in that: A pressure swing adsorption system comprising a plurality of pressure swing adsorption units (1), wherein the plurality of pressure swing adsorption units (1) are connected in parallel; It also includes a mixing device (2), in which the original gas and the gas that has passed through the pressure swing adsorption system are mixed.

2. A gas concentration and separation device according to claim 1, characterized in that: The pressure swing adsorption unit (1) comprises an adsorption tower (3), the adsorption tower (3) is filled with an adsorbent (4), the raw gas enters from the lower end of the adsorption tower (3), is adsorbed by the adsorbent (4), and is discharged from the upper end of the adsorption tower (3).

3. A gas concentration and separation device according to claim 2, characterized in that: The lower end of the adsorption tower (3) is connected to a gas extraction pump (5), and the gas extraction pump (5) delivers the extracted gas into the adsorption tower (3). The pressure output by the gas extraction pump (5) is a slight positive pressure, which is less than 15 KPa.

4. A gas concentration and separation device according to claim 2, characterized in that: The lower end of the adsorption tower (3) is connected to a vacuum pump (6), and the vacuum pump (6) provides negative pressure to the adsorption tower (3), so that the gas adsorbed by the adsorbent (4) is desorbed and discharged from the vacuum pump (6).

5. The gas concentration and separation equipment according to claim 1, characterized in that: The mixing device (2) comprises a mixing box (7), the upper end of the mixing box (7) is provided with a first air inlet (8) and a second air inlet (9), the lower end of the mixing box (7) is provided with an exhaust port (10), and the mixed gas is discharged from the exhaust port (10).

6. A gas concentration and separation device according to claim 5, characterized in that: A flow guide device is provided in the mixing box (7), the flow guide device comprising flow guide units (11) arranged in sequence, each flow guide unit (11) comprising two groups of closely attached flow guide boxes (12), and the air intake directions of two adjacent groups of flow guide boxes (12) are different.

7. A gas concentration and separation device according to claim 6, characterized in that: The cross-sectional area of ​​the air inlet of the guide box (12) is less than half the cross-sectional area of ​​the air outlet of the guide box (12).

8. The gas concentration and separation equipment according to claim 6, characterized in that: The cross-sectional area of ​​the air outlet of the guide box (12) is approximately equal to the cross-sectional area of ​​the guide box.

9. The gas concentration and separation equipment according to claim 6, characterized in that: A plurality of sets of vertical plates (13) are fixed in the flow guide box (12), and the vertical plates (13) are arranged at an angle to divide the flow guide channel into a plurality of mutually independent flow guide channels, wherein the cross-sectional area of ​​the flow guide channel at the outlet gradually decreases towards the direction approaching the air inlet.

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