GAS EMISSION REDUCING SYSTEM AND METHOD FOR REDUCING AT LEAST ONE OF GREEN HOUSE GASES AND AMMONIA EMISSIONS FROM SLURRY STORED IN ONE OR MORE SLURRY STORAGE TANKS

Abstract

A system and a method for reducing emission of greenhouse gasses is provided, in particular at least one of methane, laughing gas, nitrogen oxides, and ammonia from slurry stored in one or more slurry storage tanks. The method includes continuously maintaining slurry stored in a slurry storage tank under acidic conditions. The method includes the steps of: A: monitoring pH in the slurry present in the slurry storage tank by one or more pH sensors arranged in contact with the slurry in the slurry storage, B: checking if the detected pH exceeds above an upper threshold, such as an upper threshold set at pH=7, C: activate acid addition when the monitored pH exceeds the upper threshold, D: while stirring, adding acid until pH in the slurry is adjusted to within a range between the upper threshold and a lower threshold, such as between pH=2 and pH=7, in particular between pH=5 to pH=7, or more preferred pH=5 and pH=6, and repeating steps C-D when the detected pH of step A exceeds the upper threshold.

Claims

1. A method for reducing emission of greenhouse gasses or at least one of methane, laughing gas, nitrogen oxides, and ammonia from slurry stored in one or more slurry storage tanks, which method comprises continuously maintaining slurry stored in a slurry storage tank under acidic conditions, and wherein the method includes the steps of A: monitoring pH in the slurry present in the slurry storage tank by one or more pH sensors arranged in contact with the slurry in the slurry storage, B: checking if the detected pH exceeds above an upper threshold, such as an upper threshold set at pH=7, C: activate acid addition when the monitored pH exceeds the upper threshold, D: while stirring, adding acid until pH in the slurry is adjusted to within a range between the upper threshold and a lower threshold, wherein the upper threshold and a lower threshold is one of between pH=2 and pH=7, between pH=5 to pH=7, or between pH=5 and pH=6, and repeating steps C-D when the step detected pH of step A exceeds the upper threshold.

2. The method according to claim 1, wherein the acid is added to the slurry storage directly from a truck tanker trailer, and where a crane arm arranged on the tanker trailer adds the acid to the slurry while also stirring the slurry in the slurry storage by a pump or a mixer arranged on the crane arm.

3. The method according to claim 1, wherein further sensor monitors the concentration of at least one of P, N, methane and other components in the slurry, wherein at least one of the sensors and the pH sensor are arranged in the slurry storage or on the crane arm or in the crane arm's slurry pump or slurry mixer or where the further sensor is arranged on the tanker and connected to the slurry flow passages by at least one of piping and hoses.

4. The method according to claim 1, wherein at least one of pH sensor values and values from monitoring concentration of at least one of P, N, methane and other components are transferred to a database, and where the database contains identification tags for one or more slurry storage tanks, and stores at least the pH values related to the slurry storage tanks or to each of the tagged slurry storage tanks, or one or more values for the concentration of at least one of P, N, methane and other components, and wherein a time stamp is created when acid is added to the tagged slurry storage and where the time stamps are transferred to and stored in the database for each of the tagged slurry storage tanks.

5. The method according to claim 1, wherein an event is created when pH in a slurry storage exceeds the upper threshold, and where the event activates assigning a truck with the acid tanker trailer to access the slurry storage tank for adjusting pH by transfer of acid to the slurry storage tank.

6. The method according to claim 1, wherein anhydrous ammonia is added to the slurry while adding acid to at least one of the slurry and one or more additives, wherein said additive is at least one of nitrogen inhibitor, manganese nitrate, iron sulfate and other slurry additives, are injected into the slurry during the mixing process or the one or more additives are added to the acid for addition to the slurry together with the acid.

7. The method according to claim 1, wherein the method further comprises E. using the documentation of the pH value to obtain a carbon credit corresponding to the emission reduction of at least one of methane and other greenhouse gases from at least one of the one or more slurry storage tanks, and F. gathering one or more carbon credits corresponding to at least one of the emission reduction of methane and other greenhouse gases from the one or more slurry storage tanks, or registering any carbon credits obtained in relation to each slurry storage tank in the database.

8. A gas emission reducing system for reducing emission of greenhouse gasses, wherein the greenhouse gasses are at least one of methane, laughing gas, nitrogen oxides, and ammonia from slurry stored in one or more slurry storage tanks, which system comprises a fleet of one or more acid tanker trucks or as semitrailer tank trucks, where each of the one or more acid tanker truck further comprise a crane arm with an acid addition s and with at least one of a mixer and a pump for mixing or stirring slurry in a slurry storage tank and for pumping the slurry, one or more pH sensors arranged to detect pH of the slurry in the one or more slurry storage tanks, and a central control unit comprising, or in communication with at least one of a database, and the acid tank trucks and at the at least one pH sensors arranged at each of the tagged slurry storage tanks, the database comprises identification tags for each of the one or more slurry storage tanks, and where the database further comprises timestamps for each visit from an acid tank truck to each of the tagged slurry storage tanks and pH data received from the at least one pH sensors of each of the tagged slurry storages.

9. The gas emission reducing system according to claim 8, wherein the central control unit checks if the pH in the slurry present in each of the tagged slurry storage tanks exceeds above an upper threshold, such as an upper threshold set at pH=7, and activates acid addition when the monitored pH of a certain tagged slurry storage tank exceeds the upper threshold, such as by creating an alarm or by assigning one of the acid tank truck to visit the relevant tagged slurry storage tank within a predefined time range.

10. The gas emission reducing system according to claim 8, wherein the system further comprises a further sensor to monitor the concentration of one or more slurry components in each of the tagged slurry storages, wherein the sensor monitors at least one of N, P, methane and ammonia or ammonium, where the further sensor is arranged on the acid tanker truck, or in connection with at least one of the crane arm's mixing and pump and is arranged at the one or more slurry storage tanks, and where the further sensor is in communication with at least one of the control unit and database for storing of concentration data from the further sensor.

11. The gas emission reducing system according to claim 8, wherein the acid tanker truck comprises a data logger unit to log one or more data related to a tagged slurry storage, wherein the data logger unit timestamps for a visit to a tagged slurry storage, the amount of acid added to the tagged slurry storage, and at least one of a pH before and after addition of at least one of acid and concentration of further slurry components.

12. The gas emission reducing system according to claim 8, wherein a local monitoring unit comprises a monitor for monitoring at least one of the actual pH and concentration data and allows access to the data in the database that are related to one or more predefined tagged slurry storage tanks.

13. The gas emission reducing system according to claim 8, wherein the system further comprises one or more additive tanks on the acid tanker for at least one of anhydrous ammonia, nitrogen inhibitor, manganese nitrate, iron sulfate and other slurry additives, to be injected to the slurry during the mixing process.

14. The gas emission reducing system according to claim 8, wherein the system comprises one or more level sensors being arranged to determine the amount of slurry in the tank.

15. The system according to claim 8, wherein data in the database is used for the documentation of the pH value of each individual slurry tank and further as documentation for obtain one or more carbon credits relative to a calculated methane emission reduction for each of the individual slurry storage tanks, and wherein a second time stamp is created for each of the carbon credits obtained from each of the one or more slurry storage tanks.

16. The method according to claim 1, wherein the acid is added to the slurry storage directly from a floating device floating on the slurry.

17. The method according to claim 16, wherein the acid is provided from a tank, the tank positioned onshore, and the tank being in fluid connection with the floating device.

18. The method according to claim 17, wherein the tank is on a truck or trailer.

19. The method according to claim 16, wherein the floating device comprises stirrer for stirring or agitating the slurry in the slurry storage.

20. The method according to claim 19, wherein the stirrer comprises a pump for pumping the slurry or one or more mixers or at least one propeller arranged on the floating device.

21. The method according to claim 1, wherein the acid is added to the slurry storage from an agitator boat, wherein the acid is provided from a tank not positioned on the agitator boat to the agitator boat via a fluid connection, and the agitator boat comprises a stirrer for stirring or agitating the slurry.

Description

BRIEF DESCRIPTION

[0163] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0164] FIG. 1 shows changes in pH and thus ammonia emission over timea seasonin in barn acidification, in storage short term acidification and in field acidification during spreading of manure/slurry;

[0165] FIG. 2 is a graphic illustration of the weight % of ammonium N that is present as ammonia over pH;

[0166] FIG. 3 is a graphical illustration of the computerized system for monitoring pH and controlling addition of acid according to embodiments of the present invention;

[0167] FIG. 4 shows a rear part of a semitrailer tanker, with a crane arm mounted at the rear end or the tanker; and

[0168] FIG. 5 shows a mixer/pump for mounting at the crane arm.

DETAILED DESCRIPTION

[0169] A gas emission reducing system for reducing emission of greenhouse gasses, in particular methane, laughing gas and/or nitrogen oxides, and/or ammonia from slurry stored in one or more slurry storage tanks 1 is illustrated in FIG. 3. The system is based on a centralized control system, where many farmers' slurry storage tanks can be monitored and/or serviced with addition of acid. The system comprises a fleet of one or more acid tanker trucks 2, such as semitrailer tank trucks

[0170] Each of the one or more acid tanker trucks 2 further comprise a crane arm 3 with acid addition means or acid addition and with mixing and/or pumping means or pump 5 for mixing or stirring slurry in a slurry storage tank 1 and/or for pumping the slurry.

[0171] The system further comprises one or more pH sensors 5 arranged to detect pH of the slurry in the one or more slurry storage tanks 1.

[0172] The system further comprises a central control unit 8 comprising, or in communication with, a database, and/or the acid tank trucks and at the at least one pH sensors arranged at each of the tagged slurry storage tanks, e.g. via cloud 7 based technology.

[0173] The database comprises identification tags for each of the one or more slurry storage tanks, and where the database further comprises timestamps for each visit from an acid tank truck to each of the tagged slurry storage tanks and pH data received from the at least one pH sensors of each of the tagged slurry storages.

[0174] A fleet of one or more acid tanker trucks 2, such as semitrailer tank trucks that are authorized for transport of sulphuric acid and/or other strong organic or inorganic acids are assigned to the system. The assigned acid taker trailers are preferably tagged, so the system can keep track of which acid tanker trailer that visits each of the slurry storages and when. The tags are registered in the central database.

[0175] The system may keep tracks of when the acid trailers 2 visits a tagged slurry storage 1, e.g. by registering GPS data (GPS not shown in FIG. 3) for each of the trucks.

[0176] Each of the one or more acid tanker trucks 2 further comprise a crane arm 3 with acid addition means or an acid addition and with mixing and/or pumping means or pump 4 for mixing or stirring slurry in a slurry storage tank and/or for pumping the slurry.

[0177] The crane arm would thus have to be designed with flexibility to pump slurry to and from the storage facility and into the tanker. Further, an acid mixing ability and the tank layout on the tanker trailer would have to be able to accommodate both acid and slurry according to needed operation.

[0178] The system further comprises one or more pH sensors 5 arranged to detect pH of the slurry in the one or more slurry storage tanks 1. Alternatively, the one or more sensors may be integrated in the acid tank trailer's nutrient (NIR) sensor system 6 as discussed further below.

[0179] The system further comprises a central control unit 8 comprising, or in communication with, a database (not shown), and/or the acid tank trucks 2 and at the at least one pH sensors 5 arranged at each of the tagged slurry storage tanks 2.

[0180] The central control unit 8 may be a cloud 7 based system or the central control unit 8 may comprise more servers that are connected to the internet.

[0181] The database comprises identification tags for each of the one or more slurry storage tanks 1.

[0182] The central control unit receives pH sensor data from the sensors 5 arranged in connection with the tagged slurry storage tanks 1 and assigns the data to the relevant tagged slurry storage.

[0183] Then, the control unit transfers the data to the database, e.g. in the cloud 7, where at least pH data are stored together with the tags of each slurry tank.

[0184] The database preferably further comprises timestamps for each visit from an acid tank truck to each of the tagged slurry storage tanks. The time stamps are e.g. created by the control unit based on GPS tracking data from an acid tank trailer. Alternatively, a time stamp may be created manually when a truck driver scans a sign with a code, e.g. a QR code or a bar code that identifies the relevant slurry tank.

[0185] Further, data relating to the amount of slurry delivered may be transferred to the central unit together with the time stamp. Such data may e.g. be provided by detecting the volume of acid that is transferred to the slurry storage or by weighing cells that determine the weight of the acid delivered from the weight of the acid tank on the trailer and any remaining acid therein.

[0186] A control unit 8 programme comprises pH sensor 5 registration and assigning data from each of the pH sensors 5 to the relevant tagged slurry storage tank 1. The central control unit then transfers these data to the relevant slurry storage tags in the database.

[0187] The central control unit 8 checks at regular intervals if the pH in the slurry present in each of the tagged slurry storage tanks 1 exceeds above an upper threshold, such as an upper threshold set at pH=7. Or preferably a pH upper threshold of pH=6 or between 5 and 6.

[0188] If the threshold is exceeded, the central control unit 8 activates acid addition when the monitored pH of a certain tagged slurry storage tank 1 exceeds the upper threshold, such as by assigning one of the acid tank trucks to visit the relevant tagged slurry storage tank within a predefined time range. The predefined time period could e.g. be within a week or 1-5 days, such as 2-3 days when a first threshold is exceeded, e.g. pH=6. Optionally, a shorter time period of e.g. 1-48 hours may be assigned if a second upper threshold of pH=7 is exceeded.

[0189] This enables a fully automated system, where truck logistics may be integrated into the control unit.

[0190] Alternatively, when the threshold is exceeded, the central control unit 8 activates acid addition when the monitored pH of a certain tagged slurry storage tank exceeds the upper threshold, by creating an alarm. The alarm may be audible and/or visible and is given from the central unit to prompt the hauler to manually assign an acid truck to visit the relevant slurry storage with PH sensor data alarm.

[0191] Alternatively, or in addition, the farmer may receive an alarm and/or a notification, e.g. in a text message, and/or in a local monitoring unit 9 program, e.g. provided as an application in a farmer's computer, or another portable unit, e.g. a tablet or a mobile phone device. The farmer can then manually react on the alarm/notification by ordering the hauler to deliver acid to the relevant slurry storage tank.

[0192] The system further comprises further sensor means or sensor 6, such as a NIR sensor as discussed above, to monitor the concentration of one or more slurry components in each of the tagged slurry storages 1, in particular N, P, methane and/or ammonia/ammonium. The further sensor means or sensor, i.e. the nutrient sensor 6, is arranged on the acid tanker truck, such as in connection with the crane arm's mixing and/or pumping means or pump 13. Alternatively, the further sensor means or sensor 6 are arranged on the tanker and connected to the slurry flow passages by piping and/or hoses (not shown).

[0193] The nutrient sensor 6 is in communication with the control unit 8 and/or database for storing of concentration data from said further sensor means or sensor, e.g. by wireless connection or by intermediate storage in a datalogger on the truck as described above.

[0194] The nutrient sensor 6 is arranged in contact with the liquid slurry circulating through the acid injection and/or mixing means or mixer 13 arranged on the crane arm 12. e.g. by being integrated into the mixer/injection unit 13 e.g. as shown in FIG. 5, where the nutrient sensor 6 is arranged on or in the slurry flow channel 14 through the mixer head 13. In the slurry flow channel 14, addition of acid is also provided, e.g. by an ejector unit (not shown) Alternatively, the further sensor means or sensor may be arranged separately on the acid tank truck, e.g. in a detachable fitting (not shown) that is arranged between a hose or piping means or pipe that is connected to the slurry tank truck and the acid mixing and/or the slurry mixing means or slurry mixer.

[0195] The nutrient concentration data will comprise a number of discrete data that are collected at each visit by an acid tank trailer truck. These data are stored in the database and together with the relewant tagged slurry storage tank, and any other data related to the relevant tagged slurry storage tank.

[0196] The acid tanker may comprise a data collection and/or transfer unit 15 that is preferably in online communication with the central control unit 8, e.g. via a cloud 7 based link, whereby the detected data may be transferred directly to provide real time information to the hauler's central control unit 8 and/or to the farmer's monitoring unit 9.

[0197] The system preferably comprises one or more level sensors (not shown), which are arranged to determine the amount of slurry in the slurry storage tank. The level data are preferably also transmitted to the central control unit and/or stored in the database together with other data related to the tagged slurry storage. This allows the system to determine the actual total volume of slurry present in the slurry storage. Thus, the total slurry volume does not need to be calculated using estimates for evaporation and/or addition of water (e.g. if flush technology is applied in the barn.

[0198] Alternatively, the level sensor means or sensor comprise one or more distance measuring means or distance measurer, positioned on the slurry storage tank, the mixer, the slurry conduit and/or the pump means or pump, wherein the measuring means or measurer is adapted for measuring the distance between the top of the slurry storage tank and the slurry surface level, whereby the amount of slurry in the slurry storage tank can be determined.

[0199] The farmer's local slurry storage monitoring unit 9 may further comprise computing means or computer that can assist the farmer in computing the amount of slurry to spread in a certain field from data related to the soil type and/or condition, crop type etc. In addition, the farmer's monitoring unit may comprise a reporting module (not shown) that enables the farmer to create reports to control authorities 10 on pH in slurry storage, nutrient concentration and/or when acid addition was performed. In a variant these reports are created automatically and transferred automatically to the control authorities.

[0200] Similarly, the hauler's control unit 8 may comprise a second report module for creating reports on acid tanker transports, and any required documentation that the control authorities require for maintaining the hauler's authorisation for transport of dangerous goods.

[0201] Preferably, each of the sensor means or sensor 5, 6 or datalogger units on the acid tanker trucks 2, and/or the tagged slurry storage tanks 1 and/or the farmer's monitoring unit are in wireless contact with the control unit 8 and/or the central database, such as via a cloud 7 based communication link and/or mobile phone connections as illustrated with the dotted lines in FIG. 3.

[0202] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0203] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements. The mention of a unit or a module does not preclude the use of more than one unit or module.

REFERENCES

[0204] 1. slurry storage [0205] 2. tank traileracid tanker [0206] 3. crane arm [0207] 4. mixer/pump [0208] 5. pH sensor [0209] 6. nutrient sensor [0210] 7. cloud [0211] 8. control unit/hauler unit [0212] 9. farmer's monitoring unit [0213] 10. control authorities [0214] 11. crane arm links [0215] 12. crane arm end with adaptor for mixer/pump [0216] 13. pump/mixer for adaptor [0217] 14. slurry flow channel in mixer [0218] 15. data collection and/or transfer unit on tanker