CN1092037A - Heat-exchange type gas-producing process with natural gas as material - Google Patents
Heat-exchange type gas-producing process with natural gas as material Download PDFInfo
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- CN1092037A CN1092037A CN93110900A CN93110900A CN1092037A CN 1092037 A CN1092037 A CN 1092037A CN 93110900 A CN93110900 A CN 93110900A CN 93110900 A CN93110900 A CN 93110900A CN 1092037 A CN1092037 A CN 1092037A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
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Abstract
The present invention presses H with Sweet natural gas and steam
2O/ ∑ C=2.5-2.7 mixed enters the interior nickel catalyzator bed of heat exchange type one-stage converter conversion tube and carries out conversion reaction after the preheating.Methane content is 26-32% in the reforming gas, enters secondary reformer with oxygen-rich air and produces partial oxidation reaction and degree of depth conversion reaction.The process air add-on is kept reforming gas and is consisted of (CO+H
2)/N
2=2.8-3.1, the oxygen add-on is controlled by methane content remaining in the secondary reformer exit gas.The present invention produces hydrogen or hydrogen, nitrogen is energy-conservation, and power waste is little, is easy to regulate the control Production Flow Chart, and cost is low, and being suitable for the Sweet natural gas is the synthetic ammonia or the methanol plant of raw material.
Description
It is relevant that the technology of hydrogen or hydrogen, nitrogen is produced in the present invention and hydrocarbon steam conversion.
The LCA technology of traditional hydrocarbon steam conversion gas-made technology such as Britain I.C.I company, be with Sweet natural gas, the middle steam-heated cal(l)andria of pressing is mixed, desulfurization, enter the heat exchange type one-stage converter after the heat exchange, carry out indirect heat exchange by the gas from secondary reformer between pipe, one section reforming gas enters secondary reformer to be mixed with the excessive preheated air of adding and carries out the degree of depth and transform.Two sections reforming gas enter after the interchanger heat exchange and enter follow-up operation after through exhaust gas boiler is produced steam through one-stage converter.420 ℃ of the one-stage converter process gas temperature of LCA technology, one-stage converter H
2O/ ∑ C2.5, one-stage converter top hole pressure are 3.73mpa.Add than stoichiometric ratio to secondary reformer and to many excess air of 80-90%, form in order to guarantee the hydrogen synthetic gas: H
2/ N
2=3, must remove and produce excessive N in the gas
2, therefore in main flow, be provided with the absorption of PSA(transformation) and device.Therefore a H is just arranged
2Rate of recovery problem.H in LCA technology
2The rate of recovery is 89%.CO adopts one section equitemperature conversion, and 200-250 ℃ of low-temp desulfurization adopted in desulfurization, adopts middle pressure steam heating Sweet natural gas to desulfurization temperature.LCA technology is owing to having added excess air to secondary reformer, so be provided with multi-functional PSA(molecular sieve in the operation of back) tripping device.It not only will remove excessive N
2, also require to remove CO simultaneously
2, CO etc. not only bring power waste, and H
2The rate of recovery only 89%.Energy consumption height on the one hand, PSA separates the gassing calorific value and reaches about 3360KJ/Kg on the other hand, can't utilize at all.Because polyfunctional molecule sieve is placed on the main flow, in case during the molecular sieve performance fluctuation, will have a strong impact on Ammonia Production, even cause that whole devices stop production.Because need to go into operation the initiator and the catalyzer of igniting that goes into operation, this catalyzer is that palladium, platinum type are very valuable, cost height, complex procedures.
The purpose of this invention is to provide a kind of thermo-efficiency height, energy-conservation power waste is little, is easy to regulate control, and running cost is low, H
2The heat-exchange type gas-producing process with natural gas as material that the rate of recovery is high.
The present invention is achieved in that
The present invention is at process furnace heating Sweet natural gas and hydrogen mixed gas, steam, air, the selexol process of desulfurizer after with preheating, Sweet natural gas gas mixture after steam, the desulfurization enters the heat exchange type one-stage converter and carries out conversion reaction after importing and exporting the further heat exchange intensification of interchanger, one section reforming gas enters secondary reformer and proceeds to deepen conversion reaction, two sections reforming gas enter the through exhaust gas boiler byproduct steam after one-stage converter and the heat exchange of import and export interchanger, enter post-order process then.Among the present invention, Sweet natural gas and process steam that desulfurization is qualified are pressed H
2The mixed of O/ ∑ C=2.5-2.7, be preheated to 480-530 ℃ and enter to flow through in the heat exchange type one-stage converter conversion tube and be filled in nickel catalyzator bed in the pipe through importing and exporting interchanger, outside conversion tube, the thermal source that high-temperature technology gas provided from secondary reformer in the Heat Room carries out hydrocarbons steam reforming reactions such as methane:
Methane content is 26-32% in one section reforming gas, the reforming gas temperature that goes out one-stage converter is 600-700 ℃, pressure is 0.8Mpa-3.0Mpa, the oxygen-rich air that gets from 480-530 ℃ process air of process furnace and the oxygen mix that from oxygenerator purity is 80-95% enters secondary reformer to be mixed with the one section reforming gas that enters and produces partial oxidation reaction, for the degree of depth conversion reaction of methane provides required heat, react as follows:
The air add-on is kept two sections reforming gas and is consisted of: (CO+H
2)/N
2Remaining methane content was controlled during the requirement of=2.8-3.1, oxygen add-on were worked off one's feeling vent one's spleen by secondary reformer.
The content of oxygen of the present invention in oxygen-rich air can be: 38-45%(weight).
One-stage converter of the present invention comprises housing 11, pipe core 12, tube bank plate 13, traverse baffle 15, tube bank 16, water jacket 17, pigtail 18 raises the nose above water to breathe 19, fireproof heat-insulating lining 20, two sections reforming gas imports 22,21, two sections reforming gas outlets 24 of lower section catalyst, epimere catalyzer 23, Heat Room 14, stuffing box 26.Lower section catalyst 21 is CN-23-1(Φ 16 * 10 7 holes), the epimere catalyzer is CN-23-2(Φ 10 * 10 4 holes).Transforming caliber is Φ 89 * 5-Φ 108 * 5.The one-stage converter unstripped gas enters the stove upper space by import 25 and enters conversion tube again.The conversion tube lower end is connected with pigtail, and pigtail is logical raises the nose above water to breathe, and raises the nose above water to breathe to lead to pipe core, and one section reforming gas is gone out by pipe core and entered secondary reformer.Heat Room 14 has two sections reforming gas imports 22, outlet 24.
Secondary reformer has one section reforming gas inlet 27,28, two sections reforming gas outlets 35 of oxygen-enriched inlet, Φ 50-Φ 25 corundum ball layers 29, CN-24-1 catalyst layer 30, CN-24-2 catalyst layer 31, CN-20 catalyst layer 32, Φ 25 corundum ball layers 33, water jacket 34.Desulfurizer is the MF-1 desulfurization catalyst, and hydrogen content is 2-5%(weight % in the Sweet natural gas of institute's desulfurization and the hydrogen mixed gas).
The present invention moves to the autothermal secondary reformer with a big chunk methane and carries out degree of depth conversion reaction, and the thermo-efficiency height is energy-conservation.In secondary reformer, add oxygen-rich air rather than add excess air, avoided removing excessive N
2, CO
2, the problem that power waste that CO brings and hydrogen recovery rate are low.Thereby having removed the polyfunctional molecule sieve in main flow has avoided having improved productivity because of the influence of its performance inconsistency to Production Flow Chart.The present invention keeps normal methane controlling index by regulating the amount of oxygen that adds in the secondary reformer, is easy to regulate control.System operation elasticity is big, and production also can be kept in low 20% o'clock of arriving normal load.The present invention does not need to be provided with in addition other equipment that goes into operation, owing to adopt process furnace that thermal source is provided, when going into operation, opens secondary reformer earlier, and second step was opened the heat exchange type one-stage converter again, and is easy to operate, with low cost.With system gas of the present invention, ammonia consumption Sweet natural gas 750-800 standard cubic meter per ton, oxygen consumption 160-190 standard cubic meter (by pure oxygen).CO about 12% can be provided more
2, have obvious energy-saving effect.Utilize the present invention to being that the synthesis ammonia plant of raw material is transformed with the Sweet natural gas, need only newly-built gas head, do not influence production, reduced investment is taken up an area of fewly, has remarkable economic efficiency.
Following is accompanying drawing of the present invention
Fig. 1 is a process flow sheet of the present invention.
Fig. 2 is the one-stage converter structure iron.
Fig. 3 is the secondary reformer structure iron.
Following is embodiments of the invention:
Sweet natural gas, the gas mixture of hydrogen (hydrogen accounts for 2% or 3.5% or 5%) enter process furnace and 1. are heated to 400 ° and enter the MF-1 desulfurizer 4., and the total sulfur in the unstripped gas is removed to below the 0.1ppm.Sweet natural gas gas mixture after the desulfurization with in process furnace, be heated to the steam of equal temperature by H
2O/ ∑ C=2.5(or 2.6 or 2.7) mixed, 5. be preheated to 480 ℃ (or 500 ℃ or 530 ℃) through importing and exporting interchanger, enter in the heat exchange type one-stage converter conversion tube 16 2., at nickel catalyzator CN-23-2, under the effect of CN-23-1, outer by means of conversion tube from secondary reformer two sections thermals source that reforming gas provided 3., carry out the steam reforming reaction of hydrocarbons such as methane.Use armatine alkane and reduce to 26%(or 29% or 32%).One section reforming gas enters 3. top of secondary reformer, from 400 ℃ of air of process furnace and from the oxygen mix of PSA oxygenerator and oxygen-rich air enter the secondary reformer neck.The purity of oxygen is 80% or 87% or 95%.Oxygen-rich air mixes with the one section reforming gas that enters secondary reformer and produces partial oxidation reaction, provides institute's heat requirement for the degree of depth of methane transforms.The process air add-on is kept two sections reforming gas and is consisted of (CO+H
2)/M
2=2.8(or 2.9 or 3.1).The oxygen add-on is controlled by methane content remaining in the secondary reformer exit gas.The high-temperature technology gas that goes out secondary reformer enters between the pipe of heat exchange type one-stage converter and carries out heat exchange with conversion tube internal reaction thing, enter after self temperature reduces import and export interchanger 5. with raw natural gas and process steam charge heating to 480-530 ℃, enter the steam that soft water that 7. 7. 6. waste heat boiler enter soft water preheater with CO middle temperature transformation stove produces required pressure rating then.The temperature of process gas itself reduce to 360 ° enter then the CO low temperature shift converter 8. with watercooler 10..Just identical with the conventional process flow that with the Sweet natural gas is raw material employing steam reforming system gas later on.
Claims (3)
1, heat exchange gas formula vapour transforms gas-making process, be included in process furnace heating Sweet natural gas, hydrogen mixed gas, steam, air, the selexol process of desulfurizer after with preheating, steam, Sweet natural gas gas mixture after the desulfurization enters the heat exchange type one-stage converter and carries out conversion reaction after importing and exporting interchanger heat exchange intensification, one section reforming gas enters secondary reformer and proceeds to deepen conversion reaction, two sections reforming gas are through one-stage converter and advance, enter through exhaust gas boiler after the heat exchange of outlet interchanger and produce steam, enter the postorder operation then, it is characterized in that Sweet natural gas that desulfurization is qualified and process steam mixed by H2O/ Σ C=2.5-2.7, be preheated to 480-530 ℃ through the import and export interchanger and enter the nickel catalyzator bed of flowing through in the heat exchange type one-stage converter conversion tube, carry out hydrocarbons steam reforming reactions such as methane by means of the outer thermal source that high-temperature technology gas provided of conversion tube from secondary reformer:
Methane content is 26-32% in one section reforming gas, going out the one-stage converter process gas temperature is 600-700 ℃, pressure is 0.8Mpa-3.0Mpa, the oxygen-rich air that gets from 480-530 ℃ process air of process furnace and the oxygen mix that from oxygenerator purity is 80-95% enters secondary reformer neck mixing tank to be mixed with one section reforming gas of going into the secondary reformer top and produces partial oxidation reaction, for the degree of depth conversion reaction of methane provides required heat, reaction formula is as follows:
The process air add-on is kept two sections reforming gas and is consisted of: (CO+H2)/requirement of N2=2.8-3.1, the oxygen add-on is controlled by methane content remaining in the secondary reformer exit gas.
2, heat-exchange type gas-producing process with natural gas as material according to claim 1 is characterized in that the content of oxygen in oxygen-rich air is 38-45%(weight).
3, heat-exchange type gas-producing process with natural gas as material according to claim 1 and 2 is characterized in that said one-stage converter comprises housing 11, pipe core 12, tube bank plate 13, traverse baffle 15, tube bank 16, water jacket 17, pigtail 18 raises the nose above water to breathe 19,20, two sections reforming gas imports 22 of fireproof heat-insulating lining, lower section catalyst 21, two sections reforming gas outlets 24, epimere catalyzer 23, Heat Room 14, stuffing box 26.Lower section catalyst 21 is CN-23-1(Φ 16 * 10 7 holes), the epimere catalyzer is CN-23-2(Φ 10 * 10 4 holes).Transforming caliber is Φ 89 * 5-Φ 108 * 5.The one-stage converter unstripped gas enters the stove upper space by import 25 and enters conversion tube again.The conversion tube lower end is connected with pigtail, and pigtail is logical raises the nose above water to breathe, and raises the nose above water to breathe to lead to pipe core, and one section reforming gas is gone out by pipe core and entered secondary reformer.Heat Room 14 has two sections reforming gas imports 22, outlet 24.
Secondary reformer has one section reforming gas inlet 27,28, two sections reforming gas outlets 35 of oxygen-enriched inlet, Φ 50-Φ 25 corundum ball layers 29, CN-24-1 catalyst layer 30, CN-24-2 catalyst layer 31, CN-20 catalyst layer 32, Φ 25 corundum ball layers 33, water jacket 34.Desulfurizer is the MF-1 desulfurization catalyst, and hydrogen content is 2-5%(weight % in the Sweet natural gas of institute's desulfurization and the hydrogen mixed gas).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93110900A CN1033224C (en) | 1993-03-10 | 1993-03-10 | Heat-exchange type gas-producing process with natural gas as material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93110900A CN1033224C (en) | 1993-03-10 | 1993-03-10 | Heat-exchange type gas-producing process with natural gas as material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1092037A true CN1092037A (en) | 1994-09-14 |
| CN1033224C CN1033224C (en) | 1996-11-06 |
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ID=4988716
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN93110900A Expired - Fee Related CN1033224C (en) | 1993-03-10 | 1993-03-10 | Heat-exchange type gas-producing process with natural gas as material |
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| CN (1) | CN1033224C (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU745685B2 (en) * | 2000-08-16 | 2002-03-28 | Mitsubishi Heavy Industries Engineering, Ltd. | Method of manufacturing synthesis gas |
| CN100427384C (en) * | 2005-06-28 | 2008-10-22 | 庞玉学 | Process for preparing CO and synthetic gas and methanol by steam conversion of hydrocarbons |
| CN102382324A (en) * | 2011-12-15 | 2012-03-21 | 周其强 | Application of organosilicon residues to preparation of silicon rubber modified masterbatches |
| CN101679030B (en) * | 2007-05-24 | 2012-10-31 | 爱沃特株式会社 | Carbon monoxide gas generation apparatus and method and carburization atmosphere gas generation apparatus and method |
| CN103303866A (en) * | 2012-03-15 | 2013-09-18 | 上海汉兴能源科技有限公司 | Method for producing hydrogen or/and hydrogen-carbon monoxide synthesis gas by converting light dydrocarbon raw material |
| CN105987613A (en) * | 2015-03-16 | 2016-10-05 | 易普森国际有限公司 | Process gas treatment device for the treatment of process gas for an industrial furnace installation, and industrial furnace installation for gas carburizing and for hardening of metallic workpieces |
| CN108373138A (en) * | 2018-03-14 | 2018-08-07 | 中国成达工程有限公司 | A kind of synthesis gas preparation system and preparation process |
| WO2019112480A1 (en) * | 2017-12-07 | 2019-06-13 | Публичное Акционерное Общество "Газпром " | Apparatus and method for producing hydrogen-containing gas |
| CN110127611A (en) * | 2019-05-16 | 2019-08-16 | 宁夏渝丰化工股份有限公司 | Ammonia synthesis process raw material gas shift heating system |
-
1993
- 1993-03-10 CN CN93110900A patent/CN1033224C/en not_active Expired - Fee Related
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU745685B2 (en) * | 2000-08-16 | 2002-03-28 | Mitsubishi Heavy Industries Engineering, Ltd. | Method of manufacturing synthesis gas |
| CN100427384C (en) * | 2005-06-28 | 2008-10-22 | 庞玉学 | Process for preparing CO and synthetic gas and methanol by steam conversion of hydrocarbons |
| CN101679030B (en) * | 2007-05-24 | 2012-10-31 | 爱沃特株式会社 | Carbon monoxide gas generation apparatus and method and carburization atmosphere gas generation apparatus and method |
| CN102382324A (en) * | 2011-12-15 | 2012-03-21 | 周其强 | Application of organosilicon residues to preparation of silicon rubber modified masterbatches |
| CN102382324B (en) * | 2011-12-15 | 2013-03-20 | 周其强 | Application of organosilicon residues in preparation of silicon rubber modified masterbatches |
| CN103303866A (en) * | 2012-03-15 | 2013-09-18 | 上海汉兴能源科技有限公司 | Method for producing hydrogen or/and hydrogen-carbon monoxide synthesis gas by converting light dydrocarbon raw material |
| CN105987613A (en) * | 2015-03-16 | 2016-10-05 | 易普森国际有限公司 | Process gas treatment device for the treatment of process gas for an industrial furnace installation, and industrial furnace installation for gas carburizing and for hardening of metallic workpieces |
| WO2019112480A1 (en) * | 2017-12-07 | 2019-06-13 | Публичное Акционерное Общество "Газпром " | Apparatus and method for producing hydrogen-containing gas |
| KR20200096208A (en) * | 2017-12-07 | 2020-08-11 | 푸블리크노에 악찌오네르노에 옵쉐스트보 “가츠프롬” | Apparatus and method for obtaining hydrogen containing gas |
| CN111542492A (en) * | 2017-12-07 | 2020-08-14 | 俄罗斯天然气工业公开股份公司 | Apparatus and method for producing hydrogen-containing gas |
| KR102379772B1 (en) * | 2017-12-07 | 2022-03-25 | 푸블리크노에 악찌오네르노에 옵쉐스트보 “가츠프롬” | Apparatus and method for obtaining hydrogen containing gas |
| CN111542492B (en) * | 2017-12-07 | 2023-04-25 | 俄罗斯天然气工业公开股份公司 | Apparatus and method for producing hydrogen-containing gas |
| CN108373138A (en) * | 2018-03-14 | 2018-08-07 | 中国成达工程有限公司 | A kind of synthesis gas preparation system and preparation process |
| CN108373138B (en) * | 2018-03-14 | 2020-05-05 | 中国成达工程有限公司 | Synthetic gas preparation system and preparation process |
| CN110127611A (en) * | 2019-05-16 | 2019-08-16 | 宁夏渝丰化工股份有限公司 | Ammonia synthesis process raw material gas shift heating system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1033224C (en) | 1996-11-06 |
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