DESC:TECHNICAL FIELD
[0001] The present disclosure relates to systems and methods for detecting presence of toxic gases and more particularly, relates to systems and methods for detecting presence of the toxic gases in petroleum refining facilities.

BACKGROUND
[0002] Fugitive emissions in petroleum refining facilities may escape from leaking tubing, valves, connections, flanges, gaskets, steam traps, gas conveyance systems, and numerous other components. Depending on the refinery process scheme, fugitive emissions may comprise: Hydrogen; Methane; Volatile Organic Compounds (ethane, benzene, toluene); Inorganic gases (H2S, NH3, CO, CO2, SO2, NOx) etc.
[0003] The above mentioned gases may be harmful to the people working in the refineries and also to the environment. The gases may increase the pollution and breathing difficulties for the people.
[0004] Hence, there is a need for a solution for detecting presence of the above mentioned gases for preventing any harmful effects associated with the gases to spread and harm the environment and the people working in the refineries. Detection of pollutant, toxic, refining, combustible and process gases is important for public health, safety monitoring, prevention of accidents, protecting life & machinery, and environmental protection.
SUMMARY
[0005] This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the present disclosure. This summary is not intended to identify key or essential inventive concepts of the claimed subject matter, nor is it intended for determining the scope of the claimed subject matter. In accordance with the purposes of the disclosure, the present disclosure as embodied and broadly described herein, describes method and system for identifying one or more gases present in an environment.
[0006] In accordance with some example embodiments of the inventive concepts, a method for identifying one or more gases present in an environment is disclosed. The method includes varying, by a micro-hotplate, a temperature associated with a metal-oxide gas sensor for sensing presence of the one or more gases in the environment. Further, the metal-oxide gas sensor comprises one or more semiconductor metal-oxides. The method includes sensing, by a metal-oxide gas sensor, a change in resistance of the one or more semiconductors metal-oxides attached to the metal-oxide gas sensor. The method includes determining, by the metal-oxide gas sensor, the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides. The method includes identifying, by the metal-oxide sensor, the one or more gases upon interpreting data associated with the one or more gases.
[0007] In accordance with some example embodiments of the inventive concepts, a system for identifying one or more gases present in an environment is disclosed. The system includes a micro-hotplate configured to vary a temperature associated with a metal-oxide gas sensor for sensing presence of the one or more gases in the environment. Further, the the metal-oxide gas sensor comprises one or more semiconductor metal-oxides. The system includes a metal-oxide gas sensor to sense a change in resistance of the one or more semiconductors metal-oxides attached to the metal-oxide gas sensor. The metal-oxide gas sensor is configured to determine the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides. The metal-oxide sensor is configured to identify the one or more gases upon interpreting data associated with the one or more gases.
[0008] These aspects and advantages will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 illustrates an environment for detecting presence of one or more gases, in accordance with an embodiment of the present subject matter;
[0010] FIG. 2 illustrates a schematic block diagram of a for detecting presence of one or more gases, in accordance with an embodiment of the present subject matter;
[0011] FIG. 3 illustrates an operational flow diagram depicting a process for detecting presence of one or more gases, in accordance with an embodiment of the present subject matter; and
[0012] FIG. 4 illustrates a block diagram depicting a method for detecting presence of one or more gases, in accordance with an embodiment of the present subject matter.
[0013] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION
[0014] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0015] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.
[0016] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
[0017] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.
[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.
[0019] For the sake of clarity, the first digit of a reference numeral of each component of the present disclosure is indicative of the Figure number, in which the corresponding component is shown. For example, reference numerals starting with digit “1” are shown at least in Figure 1. Similarly, reference numerals starting with digit “2” are shown at least in Figure 2, and so on and so forth.
[0020] Embodiments of the present subject matter are described below in detail with reference to the accompanying drawings.
[0021] Fig. 1 illustrates an environment 100 including a system 102 for detecting one or more gases present in the environment 100, in accordance with an embodiment of the present subject matter. In an embodiment, the environment 100 may be a petroleum refining facility and the presence of the one or more gases in the environment may indicate a leak of the one or more gases. Examples of the one or more gases may include, but are not limited to, Hydrogen Sulfide (H2S), Sulphur dioxide (SO2), Nitrogen oxide (NOx), Methane CH4. In an embodiment, the presence of the one or more gases is detected based on a resistance related to the system 102.
[0022] According to the novel aspect of the present subject matter, the system 102 may be configured to vary the temperature related to the system 102 for sensing the presence of the one or m-ore gases in the environment 100. In an embodiment, each of the one or more gases may be detected at a varied temperature. Further, the temperature may be varied between 200°C and 400 °C. As a result of varying the temperature, the system 102 may be configured to sense a change in resistance associated with the system 102.
[0023] Continuing with the above embodiment, the system 102 may be configured to determine the presence of the one or more gases present in the environment based on the change in the resistance.
[0024] Accordingly, upon determining the change in the resistance, the system 102 may be configured to identify the one or more gases present in the environment 100. In an embodiment, the identification may be based on interpreting data associated with the one or more gases present in the environment 100.
[0025] Fig. 2 illustrates a schematic block diagram 200 of the system 102 for depicting a process for detecting presence of one or more gases in the environment 100, in accordance with an embodiment of the present subject matter. In an embodiment, the environment 100 may be a petroleum refining facility and the presence of the one or more gases in the environment may indicate a leak of the one or more gases. In an embodiment, the system 102 may be configured to identify the one or more gases upon detecting the presence of the one or more gases. Examples of the one or more gases may include, but are not limited to, Hydrogen Sulfide (H2S), Sulphur dioxide (SO2), Nitrogen oxide (NOx), Methane CH4. In an embodiment, the presence of the one or more gases may be detected at varied temperatures and based on changes in resistance values of the system 102. In an embodiment, presence of each of the one or more gases may be detected between the temperature 200°C and 400 °C.
[0026] In an embodiment, the system 102 may include a micro-hotplate 202, a metal-oxide gas sensor 208, and a memory 214. Further, the micro-hotplate 202 may include a heating element 204 and a temperature sensor 206. Further, the metal-oxide gas sensor 208 may include one or more Semiconductor metal oxides 210, and one or more interdigitated electrodes 212.
[0027] In an embodiment, the micro-hot plate 202 may be configured to vary the temperature of the metal-oxide gas sensor 208. In an embodiment, the micro-hotplate 202 may be heated by a heating element 204 such that the temperature of the metal-oxide sensor 204 attached to the micro-hotplate may be increased and decreased. In an embodiment, the presence of each gas may be detected at a different temperature of the metal-oxide gas sensor 208. In an embodiment, the micro-hotplate 202 may be heated in a periodic manner such that thermal cyclic of the micro-hotplate 202 may be maintained for detecting the presence of the one or more gases.
[0028] Further, a temperature sensor 206 may be present in the system 102 for sensing the temperature of the micro-hotplate 202. In an embodiment, the temperature sensor 206 may be attached with the heating element 204 of the micro-hotplate 202. In an embodiment, the micro-hotplate 202 may exhibit a predetermined thickness. Furthermore, the micro-hotplate 202 may be structured as beams for reducing a mass associated with the micro-hotplate 202. Furthermore, the micro-hotplate 202 may be triggered by a number of heating excitation waveforms applied to the micro-hotplate 202 to enable detection of the one or more gases by the one or more semiconductor metal-oxides 210. In an embodiment, the waveforms may differ respect of magnitude & time period.
[0029] Moving forward, the metal-oxide gas sensor 208 may be configured to adsorb oxygen from the environment 100 on a surface of the metal-oxide sensor. In an embodiment, the adsorption may be performed to detect the presence of the one or more gases. In an embodiment, the presence of the gases may be detected at varied temperature upon occurrence of a reaction between the oxygen and the one or more gases present in the environment 100. In an embodiment, the one or more gases may react with oxide of the metal-oxide gas sensor 208 previously present on the surface of the metal-oxide gas sensor 208 for detecting the presence of the one or more gases present in the environment 100.
[0030] In an embodiment, the one or more semiconductor metal-oxides 210 may be attached to the metal-oxide gas sensor 208. Further, the one or more semiconductor metal-oxides 210 may be configured to detect a particular gas amongst the one or more gases. In an embodiment, at a varied temperature, a semiconductor metal-oxide amongst the one or more semiconductor metal-oxides 210 may detect the particular gas from the one or more gases. In an embodiment, the one or more semiconductor metal-oxides 210 may also be referred as one or more metal oxide films.
[0031] Continuing with the above embodiment, the one or more semiconductor metal-oxide 210 may be configured to go through a change in resistance upon reaction of the one or more gases with on of the oxygen and the oxide at the surface of the metal-oxide sensor. In extension, the one or more semiconductor metal-oxide 210 may go through the change in resistance upon detection of the one or more gases at the varied temperatures. In an embodiment, the one or more semiconductor metal-oxide 210 may include an n-type semiconductor and a p-type semiconductor. In an embodiment, the resistance of the n-type semiconductor may increase upon reaction between one of the oxygen and the oxide and the one or more gases. Further, the resistance associated with the p-type semiconductor may decrease upon reaction between one of the oxygen and the oxide and the one or more gases.
[0032] Further, the metal-oxide gas sensor 208 may be configured to sense the change in the resistance of the one or more semiconductor metal-oxide 210. In an embodiment, one or more interdigitated electrodes 212 may be present in the system 102 for probing the resistance associated with the one or more semiconductor metal-oxide 210.
[0033] Further, the memory may include data related to the one or more gases detected to be present in the environment 100. In an embodiment, the data may include concentration of the one or more gases, the change in resistance of the one or more semiconductor metal-oxide 210. In an embodiment, the concentration of the one or more gases may be detected in Parts Per Million (PPT) in the environment.
[0034] Upon sensing the change in the resistance, the metal-oxide gas sensor 208 may be configured to determine the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides 210.
[0035] Moving forward, the metal-oxide gas sensor 208 may be configured to identify the one or more gases upon detecting the presence of the one or more gases in the environment 100. In an embodiment, the identification may be based on interpreting the data associated with the one or more gases present in the memory. In an embodiment, the interpretation may be based on a plurality of criteria based on statistics, time-domain transforms, frequency-domain transforms, wavelet-domain transforms, and one or more Neural Networks (NN). Upon interpreting the data, the detected one or more gases may be identified and the concentration related to the one or more gases may be calculated in PPM.
[0036] Fig. 3 illustrates an operational flow diagram 300 depicting a process for detecting presence of one or more gases in the environment 100, in accordance with an embodiment of the present subject matter. In an embodiment, the environment 100 may be a petroleum refining facility and the presence of the one or more gases in the environment may indicate a leak of the one or more gases. Examples of the one or more gases may include, but are not limited to, Hydrogen Sulfide (H2S), Sulphur dioxide (SO2), Nitrogen oxide (NOx), Methane CH4. Further, the presence of the one or more gases may be detected by the system 102 as referred in the Fig. 1 and Fig. 2. In an embodiment, the detection may be based on a change in a resistance associated with the one or more semiconductor metal-oxides 210 attached to the metal-oxide gas sensor 208. In an embodiment, the resistance may be changed based on a change in temperature of the metal-oxide gas sensor 208.
[0037] In an embodiment, the process may include adsorbing (step 302) oxygen from the environment by the metal-oxide gas sensor 208. In an embodiment, the oxygen may be adsorbed by trapping one or more electrons on a surface of the metal-oxide as sensor 204. In an embodiment, the oxygen may be adsorbed for initiating the process for detecting the one or more gases. Further, adsorbing the oxygen may result in change in the resistance associated with the one or more semiconductor metal-oxides 210. In an embodiment, an oxide of the metal-oxide sensor may be utilised for determining the change in the resistance.
[0038] Upon adsorbing the oxygen from the environment 100, the process may proceed towards varying (step 304) the temperature related to the metal-oxide gas sensor 208 for detecting the presence of the one or more gases in the environment 100. In an embodiment, the temperature associated with the metal-oxide gas sensor 208 may be varied by the micro-hotplate 202 as referred in the Fig. 1 and Fig. 2. In an embodiment, the micro-hotplate 202 may be triggered by a number of heating excitation waveforms applied to the micro hot plate to enable detection of the one or more gases by one or more semiconductor metal-oxides 210. In an embodiment, the one or more semiconductor metal-oxides 210 are present on the metal-oxide gas sensor 208. Further, the waveforms may differ respect of magnitude & time period. In an embodiment, the temperature may be varied such that each of the one or more gases may be detected at a different value of the temperature related to the metal-oxide gas sensor 208. In an embodiment, the temperature of the micro-hotplate 202 heating the metal-oxide gas sensor 208 may be varied between 200°C and 400 °C.
[0039] In an embodiment, upon varying the temperature, the process may proceed towards sensing (step 306) the change in the resistance related to the one or more semiconductor metal-oxides 210. In an embodiment, the one or more semiconductor metal-oxides 210 may include one of an n-type semiconductor and a p-type semiconductor. In an embodiment, the change in the resistance may be a result of a reaction between the one or more gases and the oxygen on the surface of the metal-oxide gas sensor 208. In an embodiment, the change in the resistance may be a result of a reaction between the one or more gases and the oxide present on the metal-oxide gas sensor 208.
[0040] Continuing with the above embodiment, the process may proceed towards, determining (step 308) the presence of the one or more gases in the environment 100 based on the change in the resistance related to the one or more semiconductor metal-oxides 210. In an embodiment, the resistance of the n-type semiconductor may increase upon the reaction between one of the oxygen and the oxide and the one or more gases. Furthermore in an embodiment, the resistance of the p-type semiconductor may decrease upon the reaction between one of the oxygen and the oxide and the one or more gases. Further, the presence of the one or more gases may be determined based on one or more semiconductor metal-oxides 210. In an embodiment, each semiconductor metal-oxide amongst the one or more semiconductor metal-oxides 210 may be configured to sense presence of a gas amongst the one or more gases at varied temperature. In an embodiment, each of the one or more semiconductor metal-oxides 210 may be adapted to selectively detect a particular gas.
[0041] Moving forward, upon determining the presence of the one or more gases, the process may include interpreting (step 310) data associated with the one or more gases. In an embodiment, the data may include the varied temperature and the change in the resistance. In an embodiment, the interpreting may be based on on a number of criteria based on statistics, time-domain transforms, frequency-domain transforms, wavelet-domain transforms, and one or more Neural Networks (NN).
[0042] Continuing with the above embodiment, the process may proceed towards identifying (step 312) the one or more gases present in the environment 100 based on the data interpreted at the step 308.

[0043] Fig. 4 illustrates a block diagram 400 depicting a method for detecting presence of one or more gases in the environment 100, in accordance with the embodiment of the present invention. The method 400 may be implemented by the system 102 using components thereof, as described aboveFurther, for the sake of brevity, details of the present disclosure that are explained in details in the description of Fig. 1 to Fig. 3 are not explained in detail in the description of Fig. 4.
[0044] At block 402, the method includes varying, by a micro-hotplate, a temperature associated with a metal-oxide gas sensor for sensing presence of the one or more gases in the environment, wherein the metal-oxide gas sensor comprises one or more semiconductor metal-oxides.
[0045] At block 404, the method includes sensing, by a metal-oxide gas sensor, a change in resistance of the one or more semiconductor metal-oxides attached to the metal-oxide gas sensor.
[0046] At block 406, the method includes determining, by the metal-oxide gas sensor, the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides.
[0047] At block 408, the method includes identifying, by the metal-oxide sensor, the one or more gases upon interpreting data associated with the one or more gases.
[0048] While specific language has been used to describe the present disclosure, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concepts as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. Clearly, the present disclosure may be otherwise variously embodied, and practiced within the scope of the following claims.
,CLAIMS:1. A method for identifying one or more gases present in an environment, the method comprising:
varying, by a micro-hotplate, a temperature associated with a metal-oxide gas sensor for sensing presence of the one or more gases in the environment, wherein the metal oxide gas sensor comprises of one or more semiconductor metal-oxides;
sensing, by a metal-oxide gas sensor, a change in resistance of one or more semiconductor metal-oxides attached to the metal-oxide gas sensor;
determining, by the metal-oxide gas sensor, the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides; and
identifying, by the metal oxide sensor, the one or more gases upon interpreting data associated with the one or more gases.
2. The method as claimed in claim 1, wherein interpreting the data associated with the one or more gases is based on a plurality of criteria based on statistics, time-domain transforms, frequency-domain transforms, wavelet-domain transforms, and one or more Neural Networks (NN).
3. The method as claimed in claim 1, further comprising:
adsorbing, by the metal oxide sensor, oxygen from the environment on a surface of the metal oxide gas sensor.
4. The method as claimed in claim1, wherein the change in the resistance is based on a reaction between the one or more gases and the oxygen.
5. The method as claimed in claim1, wherein the change in the resistance is based on a reaction between the one or more gases and oxide present on the metal oxide gas sensor.
6. The method as claimed in claim 1, wherein each semiconductor metal-oxide amongst the of one or more semiconductor metal-oxides is configured to sense presence of a gas amongst the one or more gases at varied temperature.
7. The method as claimed in claim 1, wherein the one or more gases is one of Hydrogen Sulfide (H2S), Sulphur dioxide (SO2), Nitrogen oxide (NOx), Methane CH4.
8. The method as claimed in claim 1, wherein the one or more semiconductor metal-oxides comprise one of an n-type semiconductor and a p-type semiconductor.
9. The method as claimed in claim 1 & 6, wherein the resistance of the n-type semiconductor increases upon the reaction between the gas and the at least one gas, further wherein the resistance of the p-type semiconductor decreases upon the reaction between the gas and the at least one gas.
10. The method as claimed in claim 1, wherein the temperature is varied between 200°C and 400 °C.
11. The method as claimed in claim 1, wherein the micro hot plate exhibits a predetermined thickness and structured as beams.
12. The method as claimed in claimed 1, wherein each of the of one or more semiconductor metal-oxides is adapted to selectively detect a particular gas.
13. The method as claimed in claimed 1, wherein the micro hot plate is triggered by a plurality of heating excitation waveforms applied to the micro hot plate to enable detection of the one or more gases by the of one or more semiconductor metal-oxides, wherein the waveforms differ respect of magnitude & time period.
14. A system for identifying one or more gases present in an environment, the system comprising:
a micro-hotplate configured to vary a temperature associated with a metal-oxide gas sensor for sensing presence of the one or more gases in the environment, wherein the metal oxide gas sensor comprises of one or more semiconductor metal-oxides;
a metal-oxide gas sensor configured to:
sense a change in resistance of the one or more semiconductor metal-oxides attached to the metal-oxide gas sensor;
determine, the presence of the one or more gases present in the environment based on the change in resistance of the one or more semiconductor metal-oxides; and
identify the one or more gases upon interpreting data associated with the one or more gases.
15. The system as claimed in claim 14, wherein interpreting the data associated with the one or more gases is based on a plurality of criteria based on statistics, time-domain transforms, frequency-domain transforms, wavelet-domain transforms, and one or more Neural Networks (NN).
16. The system as claimed in claim 14 wherein, the metal oxide sensor is configured to adsorb oxygen from the environment on a surface of the metal oxide gas sensor.
17. The system as claimed in claim 14, wherein the change in the resistance is based on a reaction between the one or more gases and the oxygen.
18. The system as claimed in claim 14, wherein the change in the resistance is based on a reaction between the one or more gases and oxide present on the metal oxide gas sensor.
19. The system as claimed in claim 14, wherein each semiconductor metal-oxide amongst the of one or more semiconductor metal-oxides is configured to sense presence of a gas amongst the one or more gases at varied temperature.
20. The system as claimed in claim 14, wherein the one or more gases is one of Hydrogen Sulfide (H2S), Sulphur dioxide (SO2), Nitrogen oxide (NOx), Methane CH4.
21. The system as claimed in claim 14, wherein the one or more semiconductor metal-oxides comprise one of an n-type semiconductor and a p-type semiconductor.
22. The system as claimed in claim 14 & 19, wherein the resistance of the n-type semiconductor increases upon the reaction between the gas and the at least one gas, further wherein the resistance of the p-type semiconductor decreases upon the reaction between the gas and the at least one gas.
23. The system as claimed in claim 14, wherein the temperature of the micro hot plate heating the metal-oxide gas sensor is varied between 200°C and 400 °C.
24. The system as claimed in claim 14, wherein the micro hot plate exhibits a predetermined thickness and structured as beams.
25. The system as claimed in claim 14, wherein each of the of one or more semiconductor metal-oxides is adapted to selectively detect a particular gas.
26. The system as claimed in claimed 14, wherein the micro hot plate is triggered by a plurality of heating excitation waveforms applied to the micro hot plate to enable detection of the one or more gases by the of one or more semiconductor metal-oxides, wherein the waveforms differ respect of magnitude & time period.