Electrochemical method and system for simultaneous removal of pollutant gases

Abstract

The invention provides a method and a system for the simultaneous removal of pollutant gases CO2 / NOx / SOx from exhaust gas using multiplex catalytic DEMOP techniques provided by the MCH media, the AMPE wave treatment, the magnetic field created by spray action, and the waste heat energy.

Description

[0001] ELECTROCHEMICAL METHOD AND SYSTEM FOR SIMULTANEOUS REMOVAL OF POLLUTANT GASES

[0002] Field of the Invention

[0003] The invention relates broadly to scrubbing techniques of pollutant gas from industrial exhaust or flue gas. Particularly, the invention provides a method and a system for the treatment and removal of pollutant gases using multiplex catalytic techniques.

[0004] Background of the Invention

[0005] In recent years, increasing emphasis is placed on greenhouse gas (such as CO2 and NOX) emissions reduction, in addition to the existing industrial SOXpollutant gas abatement requirements.

[0006] There are many methods, technologies and solutions already available in the market for the removal of SOX, e.g. wet scrubber for removing the acid gases from industrial exhaust 'streams before emission to the atmosphere. However, cost effective and feasible net carbon reduction method and technology is not yet available for removing CO2 and NO (nitric oxide) simultaneously. Although there is a technology known as carbon capture and storage (CCS), the process merely separates CO2 from industrial emissions and stores it in storage facility in different physical forms so as to reduce the amount of CO2 from entering the atmosphere. In other words, CCS is a storage method instead of a carbon removal method which chemically converts CO2 into other compounds.

[0007] The common challenge in developing a feasible carbon reduction or removal process is that usually more CO2 is produced in the removal process than the CO2 emission being removed.

[0008] In chemistry teaching and concept, CO2 can easily react with other alkali materials such as hydroxides, e.g. NaOH, Mg(OH)2, Ca(OH)2, at room temperature and form carbonates or bicarbonates of Na, Mg, Ca hence fixing CO2. However, such conventional chemistry approach to remove CO2 is not practical for industrial applications due to the large quantity of alkali reactants required. Moreover, the weight of the reaction end-product equals to the total weight of the alkali material and CO2 removed, which is a much larger bulk to handle and to dispose. Also, it should be noted that when considering the CO2 emission related with the manufacturing process of the alkali reactants, there is no net CO2 removal, but more CO2 are emitted. The environmental issues, the cost of reactants and the disposal of the end-products are also the reasons why these conventional chemical CO2 fixation methods are not implemented in the industry. For example, prior art US 2012 / 0291675 A1 is a conventional CO2 chemical fixation method using alkali material to react with CO2 to form reaction end-product such as carbonates. In US 2012 / 0291675 A1 , alkali material Mg(OH)2(magnesium hydroxide) is used as a consumable reactant to react directly or indirectly with CO2 to form MgCOs which is then further react with MgO to produce other products. Heat treatment is involved in the technical solution of this prior art, however the heat is used for decomposing Mg(OH)2to produce MgO, not for the purpose of removing or breaking CO2 gas. The thermal energy source can be waste heat, although it is only used to produce reactant MgO but not for the CO2 conversion reaction.

[0009] In addition to the difficulty of removing CO2 without creating more CO2, the removal of SOXand NOXusually requires separate processes and plants, and the overall plant size to remove CO2 + SOX+ NOXwill be too big to be accommodated by plants with space constraints, especially onboard of ships. Furthermore, many SOXremoval processes also emit more CO2 such as seawater scrubbing, or lime scrubbing using CaO, etc.

[0010] The high cost of these piece-meal gas abatement plants and equipment and high operating cost also hinder the industrial implementation. It is therefore important to have a good feasible net carbon reduction solution which is economical and practical for the industry to implement, and SOXand NOXshall be removed simultaneously if present in the exhaust or flue gas.

[0011] CO2 has a stable linear structure making it difficult to break the O=C=O bonds by the conventional concept or using direct heating (thermal breaking) method, since the breakage of the carbon oxygen double bond requires extreme high temperature and energy. It is not energy efficient to remove CO2 from the thermal approach.

[0012] Other than the pollutant gas removal methods based on conventional chemical reaction, it was also suggested in prior art regarding treatment of flue gas exploiting the electrolysis effect induced by electromagnetic waves.

[0013] For example, US patent 8,529,855 B2 teaches using time varying AC wave electrolysis in saturated magnesium carbonate or sulphate solution media to force the gas phase breaking reaction of CO2, NOXand SOX. It is notable that the solution media must be kept saturated to prevent the gas from entering into water. Although the magnesium salts are not consumed in the reaction, such salts are not used as catalyst, either. Furthermore, the gas breaking reactions of CO2, NOXand SOXoperate at different pH condition, such that the removal of such gases are carried out in separate solution media. Therefore, US 8,529,855 B2 does not achieve simultaneous removal of pollutant gases, but sequential removal of SOX, CO2, and NOX. Moreover, the electromagnetic waveform including electrolysis reaction is shown in Fig. 1 A, which is a pure AC alternating wave with a varying frequency repeated with a predetermined sweeping frequency.

[0014] Another prior art US patent 10,500,542 B2 teaches using DC superimposing AC time varying frequency wave (DAC wave) for removal of CO2. However, as mentioned in the prior art, it uses the “quantum energy” of the DAC electromagnetic wave energy to remove SOX, NOXand CO2. Essentially, “quantum energy” of the DAC wave is the only energy source quoted in the prior art to break or remove the CO2 and other gases. It is stated that "... the conversion of SOX, CO2 and NOXinto their respective excited species is largely based on the vibrational and rotational quantum energy input instead of by the thermal enthalpy energy, although the exhaust gas temperature also contributes to the enthalpy energy input....”. Accordingly, under the circumstances that US 10,500,542 B2 is silent regarding any catalytic effect, the “quantum energy” of the DAC wave used must be more than the CO2 formation energy to break up the CO2. An exemplary waveform DC biased time-varying frequency pulsating electromagnetic wave used in the prior art is shown in Fig. 1 B.

[0015] It is also stated in prior art US patent 10,500,542 B2 that “When SOXis high, CO2 will be converted to carbonate / bicarbonate in water or gas, and when SOXis low, only “some” CO2 can be broken up to elemental C”. This means that the removal of carbon species depends on the concentration of other pollutant gas species in the flue gas. Moreover, the solution media used in US 10,500,542 B2 is alkali carbonates or sulphates, particularly Na2SO4 or NA2CO3, which are used for stabilizing the pH to enhance the DAC gas removal efficiency and are not required to be saturated.

[0016] At present, the waste heats from power plants are taken as “waste” and are rejected from the plant due to their temperature are too low to be utilized for the removal of CO2, NO or other applications. In fact, the temperature of these “waste” heat is still significantly higher than the atmospheric temperature and they can create “island heating” issues when discharged to the environment or warm up the temperature of seawater, river, or lake water if these water sources are used to cool down the power generation source.

[0017] In a diesel engine plant, the typical waste heat energy can account for as much as 50% of the total heat of the fossil fuel it burned, such as demonstrated in the Sanky diagram of a typical marine engine heat energy balance shown in Fig. 2. In industrial exhaust, the temperature of the waste gas it typically in the range of 250 to 400 °C, which still carry a significant amount of thermal enthalpy energy.

[0018] When these “waste heats” are used for removing the CO2 / NOX / SOX, theoretically speaking, it can potentially remove up to approximately 40-45% of the total CO2 emission. This could contribute to the international carbon reduction target, together with the effect of further reducing the temperature of the waste heat to close to atmospheric temperature without creating the secondary environment issue of waste heat. It is favorable if the thermal energy of these waste heat could be utilized for the removal of the pollutant gases.

[0019] Among the pollutant gases CO2, SOXand NOX, CO2 and NO are the most difficult to remove as they are straight linear molecules and are stable with high bond energy. They require high temperature and huge amount of thermal energy to decompose in a direct thermal gas breaking process without catalysts. Most catalysts for the removal of CO2 are the solid metal or metal alloy catalysts with CO2 conversion reactions taking place at the solid surface. However, such metal catalysts were not used in combination with electromagnetic treatments. There are also methods using dry plasma to break up CO2, but it is a pure gas phase reaction. The interfacial effect of reaction between different phases were not investigated for pollutant gas removal in prior art.

[0020] In view of the above disadvantages in prior art, it is desirable to develop a technology for the simultaneous removal of CO2, NOXand SOXin flue gas which utilizes the combined effect of solution media catalysis with electrical treatment, magnetic field, interfacial reaction and / or waste heat depletion.

[0021] Summary of the Invention

[0022] The present invention has been developed to fulfill the needs noted above and therefore has a principal object of the provision of a method and system for the simultaneous removal of pollutant gases CO2 / NOX / SOXfrom exhaust or flue gas using multiplex catalytic techniques.

[0023] The multiplex catalytic technique of the invention is named as DEMOP technique according to the following functions and characteristics of the treatment mechanism, including:

[0024] • Duplex catalytic actions of the MCH media, i.e. the electron donating electro-catalytic effect and the acid-base catalytic effect of metal ions, especially Mg2+ions. The MCH media is a liquid catalyst in the context of the present invention.

[0025] Electron donating effect created by the AMPE wave treatment generating a negative oxidation reduction potential (ORP) shift or due to the strong electron donating ORP property of the ionic media, which activates oxygen evolution reaction (OER) at the gas / media interface and produces the electro-catalytic effect.

[0026] • Magnetic field effect at the gas / media interface created by spray action of the ionic media.

[0027] • Oxygen partial pressure which controls the desired gas conversion pathway.

[0028] • Paramagnetic property of oxygen responding to the magnetic field which makes OER produces excited or energized oxygen O* species for the gas conversions.

[0029] The present invention further uses waste heat from the exhaust or flue gas or other waste heat sources as energy input for the removal of CO2 / NOX / SOXgases. The DEMOP techniques go through a few intermediate and catalytic reaction steps to convert CO2 / NOX / SOXto ions or elemental forms, which do not require high thermal energy or high temperature. In certain embodiments, the DEMOP technique is capable of removing higher percentage of CO2 and NOXin in the event when there is no, or limited supply of waste heat energy available.

[0030] The present invention is established, at least in part, on the inventors’ discovery of a novel electromagnetic waveform, namely Alternating Multi-Pulse Embedded (AMPE) wave. The AMPE wave is a frequency controlled alternating wave with multiple unidirectional pulses in each half cycle but zero net DC component in each full cycle. The AMPE wave is capable of imparting and improving the free electron donating effect required to produce the electro-catalytic effect.

[0031] In the first aspect, the present invention provides a method for the simultaneous removal of pollutant gases CO2 / NOX / SOXfrom exhaust gas, comprising the steps of: preparing a MCH media comprising magnesium ions and carbonate / bicarbonate ions, and spraying the MCH media through high pressure nozzle onto the exhaust gas to convert and remove the pollutant gases.

[0032] In present invention, the MCH media is an aqueous solution comprising dissolved Mg2+ions and CO32’ / HCOs" ions. In certain embodiments, the MCH media further comprises other metal cations such as K+, Na+, Zn2+, Ca2+, and / or other anions such as PO43', SO42', Ch, Br.

[0033] In the method of the present invention, the MCH media spray activates oxygen evolution reaction which converts H2O and OH- to O*, H+and e- at the gas / media interface under the catalytic effect of the MCH media.

[0034] In particular, the MCH media possesses electron donating electro-catalytic effect and acid-base catalytic effect.

[0035] In preferred embodiment, the method of the invention further comprises the step of treating the MCH media by an alternating multi-pulse embedded (AMPE) wave for enhancing the electron donating effect, wherein the AMPE wave comprises an alternating main AC wave and at least two unidirectional DC pulses embedded in each half cycle of the main AC wave.

[0036] In an alternative embodiment, the method of the invention further comprises the step of generating Mg2+ions in the MCH media via ionization treatment using magnesium electrodes.

[0037] Moreover, the high-speed spraying of MCH media creates a magnetic field for attracting, retaining and energizing the paramagnetic oxygen O* at the media interface generated from OER to react with the pollutant gases.

[0038] In certain embodiment, the method of the present invention further comprises the step of controlling the oxygen partial pressure of the exhaust gas to control the conversion pathway of the pollutant gases, particularly CO2 and NOX.

[0039] According to the method of the present invention, pollutant gas removal from hot exhaust gas is preferably performed with AMPE wave treated MCH media in a first stage operation so as to remove SOXand part of CO2 and NOX.

[0040] Under the circumstance that further removal of CO2 and NOXis required, a second stage operation can be performed on the treated exhaust gas from first stage operation at low temperature with high Mg2+concentration media.

[0041] In a further embodiment of the invention, the method comprises the step of replenishing the MCH media by collecting and concentrating the scrubbed water and recycling the concentrated solute for preparing the MCH media.

[0042] In the second aspect, the present invention provides a system for the simultaneous removal of pollutant gases CO2 / NOX / SOXfrom exhaust gas, comprising a first stage of closed loop comprising a MCH media tank, a reaction chamber in which a high pressure spray nozzle is arranged, and recirculating means of the MCH media, wherein the MCH media comprising magnesium ions and carbonate / bicarbonate ions, and the MCH media is sprayed through the high pressure nozzle onto the exhaust gas to convert and remove the pollutant gases.

[0043] In preferred embodiment, the system of the invention further comprises means for generating AMPE wave to treat the MCH media in the MCH media tank and / or in the recirculating lines before the spray nozzles for enhancing the electron donating effect of the MCH media, wherein the AMPE wave comprises an alternating main AC wave and at least two unidirectional DC pulses embedded in each half cycle of the main AC wave.

[0044] In preferred embodiment, the first stage reaction chamber comprises more than one levels in a vertical layer-by-layer configuration, wherein at least one spray nozzle is arranged in each level. The exhaust gas is introduced to the reaction chamber from a bottom inlet and passes through the multiple levels so as to be in contact with the media mist curtains created by the spray nozzles to induce the conversion reactions.

[0045] In certain embodiment, the first stage of closed loop further comprises heating device for heating the MCH media and the reaction chamber, preferably the heating device is connected to waste heat source.

[0046] In certain embodiment, the MCH media tank serves as a mixer for the preparation of the MCH media and has inlet ports for adding replenishment when required.

[0047] In a more preferred embodiment, the system of the invention further comprises a second stage of open or closed loop operated in conjunction with the first stage, the second stage loop comprises an Mg2+ionization tank, a reaction chamber and recirculating means. The recirculating means comprises an inlet valve for drawing from external water source and a discharge valve for discharging scrubbed water. In addition, a cooler is arranged in the recirculating path to control the temperature of the media.

[0048] The second stage reaction chamber can have the same configuration of the spray nozzle and multi levels as in the first stage. Preferably, the second stage reaction chamber has larger diameter for reducing the oxygen partial pressure in the exhaust gas by slowing down the gas speed.

[0049] In an alternative embodiment, the Mg2+ionization tank further comprises means for ionization of magnesium electrodes. The ionization can be achieved by AMPE pulse ionization, DC pulse wave / static DC ionization.

[0050] According to the system of the present invention, the pollutant gas removal in the first stage can be performed on hot exhaust gas with AMPE wave treated MCH media so as to remove SOXand part of CO2 and NOX. Moreover, for further removal of CO2 and NOX, the pollutant gas removal in the second stage can be performed on the treated exhaust gas from first stage operation at low temperature with high Mg2+concentration media.

[0051] In a further embodiment, the system of the invention comprises means for replenishing the MCH media by collecting and concentrating the scrubbed water from the second stage and recycling the concentrated solute for the preparation of the MCH media in the first stage.

[0052] The objects, characteristics, advantages and technical effects of the invention will be further elaborated in the following description of the concepts and structures of the invention with reference to the accompanying drawings. The drawings illustrate the invention by way of examples without limitation to the invention in any manner.

[0053] Brief Description of the Drawings

[0054] In the following detailed description, reference is made to the accompanying drawings. In the drawings, like reference numbers represent like parts throughout the various views.

[0055] Fig. 1 A-B shows exemplary waveforms used in prior art treatment methods.

[0056] Fig. 2 shows a Sanky diagram of a typical marine engine heat energy balance.

[0057] Fig. 3 shows an exemplary AMPE waveform of the present invention.

[0058] Fig. 4 shows basic circuitry and generation step of the AMPE wave.

[0059] Fig. 5 shows the gas removal working principle of the multiplex catalytic method of this invention.

[0060] Fig. 6 shows the conversion pathways for CO2 according to this invention.

[0061] Fig. 7 shows the schematic diagram of a DEMOP multiplex catalytic system consisting of two stages of gas removal treatment.

[0062] Fig. 8 shows the electric circuit configuration of AMPE wave treatment in the MCH media tank using inductor coils and / or capacitors treatment.

[0063] Figs. 9A-B show the electric circuit configurations of AMPE and pulse wave treatment in the Mg2+ionization tank.

[0064] Detailed Description of Embodiments

[0065] While this invention is illustrated and described in preferred embodiments, the method and system of the invention may be carried out in many different configurations, sizes, forms and materials. In the context of the present invention, terms “remove”, “scrub”, and “abate” may be used interchangeably, and in general refers to the process of decreasing the content of pollutant gases such as CO2 / NOX / SOX.

[0066] Free electron donating effect and Alternating Multi-Pulse Embedded (AMPE) wave treatment

[0067] The present invention is achieved, at least in part, by the investigation of free electron donating effect of water and the development of the AMPE wave treatment for imparting the free electron donating effect.

[0068] The free electron donating effect is provided by hydrated free electrons in water. A common case is known as free electron donating antioxidant, which can perform antioxidizing function to neutralize strong oxidizing agents such as free radicals and reactive oxygen species (ROS). Free electron donating water exhibits more negative oxidation reduction potential (ORP) compared with water in non-energized natural state. Although natural water has no free electron, it can be converted to electron donating water by the AMPE wave treatment developed by the inventor.

[0069] There are other water treatment methods and products in the market, which claim to provide antioxidizing water such as electrolyzed alkaline water by static DC electrolysis, hydrogen water, etc. However, such alkaline water and hydrogen water are not free electron donors. Static DC electrolysis cannot produce free electrons in water.

[0070] In addition to the antioxidizing effect of the free electrons, the concurrent elevation of bond vibration energy of the energized water gives the treated water much wider applications. For example, elevated bond vibration energy increases the entropy energy hence also increases the total free energy supply to the chemical reactions yet without increasing heat (enthalpy) energy. This enables many reactions which require high energy to take place without increasing temperature.

[0071] In this DEMOP invention, the key function of the AMPE wave is to induce the electro-catalytic effect in the MCH media. AMPE wave treatment is performed on the MCH media with the primary purpose of producing the strong electron donating effect and increasing bond vibration of water. This strong electron donating potential is important in the gas removal mechanism which will be detailed hereinafter.

[0072] Capacitive Frequency-Controlled Alternating Multi-Pulse Embedded Wave

[0073] The AMPE waveform of this invention is different from the other prior art waveforms discussed above and shown in Fig. 1 . In either the prior art AC wave or DC-biased AC wave, there is only one pulse in each half cycle of the waveform. Moreover, the voltage amplitude range is the same for every wave cycle. In other words, the voltage is alternating between the maximum voltage and the minimum voltage without other embedded pulses.

[0074] The AMPE waveform of the invention comprises multiple unidirectional DC pulses in each positive or negative half cycle of the wave. After each half cycle, the direction of all the multiple unidirectional DC pulses is alternated to the opposite direction. There is rms DC voltage for each half positive or negative cycle of the wave, but zero rms DC voltage for each complete cycle consisted of one positive and one negative half cycle. An exemplary AMPE waveform is shown in Fig. 3. The positive or negative half cycle unidirectional multiple DC pulses are used in the invention to produce free electrons in the MCH media. With multiple DC pulses in each half cycle, it is more effective in producing the electron donating effect.

[0075] As compared to prior art DAC waveform such as in Fig. 1 B which has rms DC voltage in every full cycle and throughout the whole waveform, the DC bias by multiple DC pulses in each positive half cycle is cancelled by the negative half cycle in present invention, hence there is zero DC bias in every positive-negative full cycle to prevent or mitigate the adverse effect of the anodic and cathodic reactions. The anodic and cathodic electrolysis reactions may produce harmful gases which are either undesirable for the purpose of pollutant gas removal or detrimental for the gas conversion reactions of the present invention.

[0076] In general, for producing the hydrated electrons, the AMPE wave of this invention has one or more of the following characteristics:

[0077] 1 ) The AMPE wave is a pulsating wave.

[0078] 2) The wave can comprise DC pulse, AC pulse, DC biased AC pulses, or other pulsating spike waves with or without time varying.

[0079] 3) The AMPE wave comprises an alternating main AC wave and multiple embedded unidirectional DC pulses.

[0080] 4) The form of AC wave and / or DC pulses can be sine wave, triangular wave, square wave, sawtooth wave, or other mixed waveforms.

[0081] 5) The main wave is positive and negative alternated wave which can be time varying or non-time varying. In specific embodiments, the main wave can be alternated at a specific alternating frequency (fa) (i.e. fixed frequency, non-time varying), or can have a sweeping frequency (i.e. time varying) with a defined sweeping cycle and frequency range. 6) In each half cycle of the main AC wave, there is embedded at least two unidirectional DC pulses, and the voltage of each pulse in each half cycle can be the same or different.

[0082] 7) Pulses in each half cycle can be of a uniform pulse form, irregular pulse form, time varying pulse form or other forms. Moreover, the pulses in the corresponding second half cycle shall be identical to the first half cycle but in the opposite voltage direction.

[0083] 8) The embedded DC pulses can also be time varying or non-time varying, i.e. having its own fixed frequency (frn) and / or sweeping frequency (fe) and frequency range with a sweeping cycle equal to or less than the half cycle of the main wave.

[0084] 9) In this invention, the parameters fa, frn, fs are as follows for treating the aqueous MCH media:

[0085] • fa can be in the range of 0.1 Hz to 10 kHz, which corresponds to a positive and negative alternating interval in the range of 1x104second to a few seconds.

[0086] • frn can be in the range of 1 Hz to 109Hz, which corresponds to a number of unidirectional DC pulse in each half cycle of the main wave of 2 to 1x105pulses, with the multiple unidirectional DC pulses being time varying or non-time varying.

[0087] • fs can be in the range of 10-2to 103Hz for the time varying DC pulses.

[0088] It is understandable that the parameters fa, frn, fs can be adjusted to optimize the treatment performance.

[0089] 10) The net root mean square (rms) voltage for each full cycle of the AMPE wave is equal to zero. That is, the rms voltage of the positive first half cycle is cancelled by the rms voltage of the negative second half cycle with equal magnitude but opposite polarity.

[0090] In the specific embodiment of an AMPE waveform as shown in Fig. 3, square waveform is adopted for both the AC wave and the DC pulses for ease of demonstration. The exemplary AMPE waveform has both time varying AC wave and DC pulses. More specifically, the frequency of the DC pulses remains constant in a full cycle of the AC wave, but varies between consecutive full AC cycles. As shown in Fig. 3, each half cycle of the main AC wave comprises 5 DC pulses. Accordingly, when the frequency of the AC wave increases in the sweeping frequency cycle, frequency of the DC pulses also increases proportionally. It is understood that the AMPE waveform of the invention may also be embodied as other forms, such as non-time varying AC wave and / or DC pulses, having different number of DC pulses between full cycles, having different duty cycle by pulse width modulation (PWM) for providing different rms voltage without changing the external voltage supply, etc. In addition, in Fig. 3 the DC pulses were embedded at 50% duty cycle, thus the rms voltage of a half cycle is equal to the half cycle DC bias mentioned above. The rms voltage can be adjusted by varying the duty cycle of the DC pulses.

[0091] Another principle of the AMPE wave treatment is the capacitive frequency control of AMPE wave. High frequency wave is used to lower the loop impedance to produce electron flow between capacitive electrode pair in semiconductive media such as water. The AMPE wave can be applied on coil to produce electromagnetic field or on closely spaced capacitor electrodes to produce capacitive field. The electromagnetic field strength for treating media can be increased by lowering the loop capacitance / impedance through high frequency to increase the net current output. With high wave frequency and closely spaced electrode arrangement, the two electrodes are no longer behaving as a resistive pair. Instead, the electrodes become a capacitive pair thus reducing the electrode to electrolyte potential by high wave frequency.

[0092] In the concept of capacitive frequency control AMPE wave treatment, in order to use frequency to control circuit impedance, the circuit must change to the concept of capacitive circuit. Accordingly, the electrodes must be placed very closely apart of one or few millimeters distance and using water or aqueous solution as dielectric semiconductive media to form into capacitor electrodes pair. When the electrode pair becomes capacitance load instead of resistive load, the whole circuit impedance is largely determined by the capacitance load of the electrode instead of resistive load.

[0093] When the electrodes are acting as capacitors, the capacitive impedance is controlled by the frequency of the wave passing through the dielectric between the capacitance plates. The capacitance and the impedance of the electrode pair is according to the following equation (1 ).

[0094] Zc= 1 / (2TTfc) (1 )

[0095] Net current flow in the circuit (exclude other resistance such as cable resistance in the circuit) is according to the following equation (2)

[0096] I = V / Zc(2) wherein Zcis impedance, c is capacitance, and f is wave frequency. Based on the above equations (1 ) and (2), by increasing the wave frequency f, the capacitive impedance Zcin equation (1 ) will be reduced, hence increasing the circuit current I in equation (2) with the same applied voltage or decreasing the voltage yet being able to maintain the same current. This will further save energy consumption.

[0097] Clearly, when the capacitive electrode pair impedance is reduced, the capacitive electrode half-cell voltage or “electrode to electrolyte” impedance will be reduced greatly without altering the external supply voltage. This enables more efficient production of free electrons in water since all energy supplied are channeled to free electron production instead of producing the anodic and cathodic reactions.

[0098] The most important outcome of the reduced half-cell voltage using frequency control method is preventing or minimizing the electrode anodic and cathodic reactions. As the current is conducted through the water media without the precondition of breaking down water molecules to generate H+and OH- ions as in the case of DC, DC pulse, or DC biased time varying wave electrolysis, it enables electrons to flow through the dielectric media between the electrode capacitance plates and produces hydrated electrons in water with no undesirable anodic and cathodic reactions. The capacitive AMPE arrangement can be installed in line as booster just before the nozzle spray.

[0099] In the AMPE wave treatment, multiple unidirectional DC pulses are embedded in each half cycle instead of just one DC pulse in each half cycle. With multiple pulse in each half cycle which duration is controlled by the alternating frequency, the time is sufficient to produce the hydrated electron effect yet able to avoid anodic and cathodic reactions. With such wave alternating frequency plus the main wave frequency control as mentioned above, free electrons can be produced in water.

[0100] Concurrently with the production of hydrated free electrons, the AMPE wave treatment also elevates the entropy energy of treated media. When polar molecules, polar bonds, hydrogen bonds and other charged ions in the media are exposed to the AMPE wave treatment of the invention, O-H bonds stretching vibration and scissoring vibration are energized and agitated greatly, thus the O-H bonds vibrate vigorously. Similarly, many other bonds and ions in the water are energized in the same way. This effect can be represented by the more efficient negative ORP shift and the larger peak variation in FTIR spectrograph, e.g. O-H stretching and O-H scissoring peaks. The AMPE DC pulses can also be time varying or non-time varying, depending on the media response to the different waves. The response of the media can be detected by the absorption peak variation amplitude in FTIR spectrograph of O-H bond stretching and O-H bond scissoring wavenumber. Large absorption peak variation amplitude indicates that the molecular bonds are sufficiently excited in the treated media. Configuration for applying the AMPE wave

[0101] In order to generate the AMPE wave of this invention, the basic components in the Printed Circuit Board comprises a waveform control IC for inputting the designed waveform and parameters, a bridge circuit consisting of two NPN MOSFETs and two PNP MOSFETs for switching and amplifying the positive and negative voltages of the waveform. The circuit is simple and efficient with significant reduction in heat loss. The AMPE wave generation step is shown in Fig. 4

[0102] For applying the AMPE wave treatment, the AMPE wave is used to drive the inductor coils in the media. The inductor coil is comparatively more efficient in producing the inductance field and the higher vibration energy can be detected by the O-H bond stretching and O-H bond scissoring absorption peak variation in the FTIR spectra. Once the MCH ionic solution is treated by AMPE wave, the strong vibration energy and the electron donating effect will make the MCH media a strong catalyst in the CO2 I NO catalytic gas removal process with the waste heat energy and temperature input.

[0103] Yet by placing the electrodes spaced further apart, the same AMPE wave with or without time varying can also be used in ionizing the magnesium blocks in the open loop tank. In this case, the electrode will follow the resistive electrode to electrolyte under the near field or far field treatment concept. There will still be electron donating effect generated in the water but as some energy is spent in ionizing the magnesium block to Mg2+ions.

[0104] The Working Principle of the Multiplex Catalytic invention

[0105] The removal of CO2, NO, NO2 and SO2 in this invention utilizes the synergetic effects of the multiplex catalytic DEMOP technique, in which the catalytic reactions for the removal of CO2 / NOX / SOXtake place at the gas / liquid interface, based on the following principles process. The pollutant gases are removed from the exhaust gas by converting it into other ions or elemental form through the synergistic effects of the following catalytic reactions and treatments. The overall gas removal working principle of the Multiplex catalytic method of this invention is summarized in Fig. 5.

[0106] 1. “Bending or distorting” the linear CO2 molecular structure to lower the activation reaction energy of CO2.

[0107] Without wishing to be bound by theory, the CO2 bending effect is achieved through using the free electron donated from the liquid media when media is in contact with the CO2 gas. The electrons pull the positive carbon end of CO2, in parallel the free Mg2+ions in the media at the gas / media interface also “pull” the negative oxygen end of the CO2 to distort the CO2 molecule. Such distortion of CO2 molecule by the duplex catalytic effect is illustrated in Fig. 5 in Step 1. Once the CO2 structure is distorted, it greatly lowers the CO2 activation energy. Accordingly, the media used in this invention acts as a liquid catalyst and has the composition listed in the following. As compared to the Mg-containing media or reactant used in prior art for the removal of CO2, the alkali media of this multiplex catalytic invention is used as catalyst instead of consumable reactant. In other words, the ionic media, particularly the Mg2+ions are substantially not consumed in the DEMOP technique of the invention.

[0108] In present invention, the ionic MCH media possess acid-base catalytic and electro-catalytic effect. MCH media of the invention comprises Mg2+ / M+ / HCOs- / COs2- / SO42' ions, wherein M+refers to metal ions and it is not limited to monovalent ions (e.g. M+, M2+, etc.). The MCH media solution itself has electron donating effect due to its negative ORP. When subjected to the AMPE wave treatment of this invention, MCH media’s free electron donating ORP negative potential shift is further boosted by the AMPE wave treatment, which further enhances the media’s electro-catalytic effect when it is in contact with CO2.

[0109] When MCH media or water is treated by AMPE wave field, it excites the water / media molecular bond vibration energy and produces / further enhances the electron donating effect. This is shown by the more negative potential of the water / MCH media after AMPE treatment.

[0110] The electron donating effect of water can be illustrated by the following formula: wherein (H2O)n*e is the electron donating excited water cluster and n(H2O) is the water clusters in neutral state after donated the electron and energy.

[0111] In addition to the electron donating effect, Mg2+and other metal ions content in the media also act as base catalytic function. The treated MCH ionic media therefore has multiple catalytic functions, the electro-catalytic and acid-base catalytic functions. Both effects allow the media to donate electrons to CO2gas once they are in contact.

[0112] In the event of inadequate Mg2+ions, other less efficient metal ions such as zinc in the media may be used, but the activation energy for CO2removal will be higher and moderate higher temperature of waste heat (e.g. above 300-350 °C) is required to compensate for the increase in activation energy.

[0113] In the event of lack of waste heat energy such as after the first stage scrubbing, more free Mg2+ions can be introduced into the media by way of AMPE pulsed wave ionization method, or other method such as DC pulse ionization with or without time varying.

[0114] The preparation, treatment, sustenance, and spraying of the MCH media during the whole DEMOP process will be discussed hereinafter in more details.

[0115] 2. The important Oxygen Evolution Reaction (OER) and the energized Oxygen species O*

[0116] For CO2 / NOX / SOXgas to ions removal conversion, it requires energized O*, H+and e- for the reactions. The electro-catalytic and acid-base electron donating effect of the media when sprayed into the gas, the electron donated from the media to gas activated the Oxygen Evolution Reaction (OER) at the gas / media interface to produce the required excited O*, H+and e- for CO2 / NOX / SOXconversion.

[0117] In the OER reaction, when electron leaves the water and crosses into the gas side, electrons will split the water molecules into Oxygen and H+at the gas / media interface which is also the anodic reaction in DC electrolysis. However, if the electrolytic oxygen is in its non-excited gaseous state, it is difficult for CO2 gas to react with oxygen. The OER reactions are illustrated in Fig. 5 in Step 2.

[0118] In order to energize the oxygen produced in the OER to improve the reactivity with CO2 gas, this invention further makes use of the paramagnetic property of oxygen which has unpaired electrons at the outermost orbital of the oxygen atom. Oxygen is therefore highly susceptible to magnetic field for its paramagnetic characteristic. Once oxygen is subjected to magnetic field, the field affects the electron state of the oxygen directly and energizes the oxygen. This energized O* is also further boosted by the vibration energy transferred from AM PE wave and / or heat transferred from gas stream.

[0119] In this invention, a magnetic field is created at the media / gas interface by using the strong spiral nozzle spray of the high ions content media. With this magnetic field created at the gas / media interface, the oxygen produced at the OER is a short life energized oxygen O*. The OER under this paramagnetic field effect, therefore, produces the following reactions. The excited O* species can also react with NOXand SOXwhichever is in contact to form respectively different ions.

[0120] 3. The creation of magnetic field at the gas / media interface

[0121] Since the co-factors including free electron donating, vibration energy transfer, heat transfer, energized O* and H+ions are all taking place at the gas / media interface, it is important to create an environment or reaction sites such that it is conducive and increase the chances for the CO2 / NOX / SOXgases to interact with these co-factors.

[0122] In this invention, magnetic field is therefore created at the gas / media interface to provide the conducive reaction sites. This magnetic field is created based on Ampere’s law and by making use of the high ions content in the media, strong electron donating effect and also the high spraying speed.

[0123] Based on Ampere’s law, when charged particle moves at a linear speed, by right hand thumb rule, magnetic field will be generated in the perpendicular direction. When high concentration of ions / charges in the media is sprayed out at a high speed in a curtain screen form, correspondingly, perpendicular to the spray, magnetic field is produced at the immediate gas / media spray curtain surface. The generation of the magnetic field B is illustrated in Fig. 5 in Step 3.

[0124] To produce a magnetic field from spray action, it requires sufficient ions content in the bulk liquid and fast travelling speed of the ions. The spiral curtain nozzle could provide such a good speedy travel for the bulk media hence able to generate a weak magnetic field. On the contrary, in conventional wet scrubber techniques using straight nozzle spray to create very fine plain water mist, it either has too little ions content or the droplet travelling speed is too slow to produce the required magnetic field.

[0125] 4. Oxygen and Oxygen Partial Pressure

[0126] With the magnetic field generated at the gas / media interface, it has a two folds effects. It can energize the oxygen O* production at the gas / media interface once it is produced from OER. Since oxygen is paramagnetic, the O* will also be drawn by the magnetic field hence enabling O* to react with CO2 and other gases NOX, and SOXto produce other ions at the gas / media interface. However, all these reactions can only take place at the gas / media interface, instead of inside the liquid as liquid has no interface for OER to take place. In such a situation, pH of the media can be maintained well although the media is exposed to a highly acidic gas environment.

[0127] The attachment or the attraction force of the magnetic field to retain O* on the gas / media interface is highly dependent on oxygen partial pressure in the scrubber. At the gas entry stage, oxygen partial pressure is higher than the exit stage. This is due to the higher back pressure at the gas entry stage. There are also other factors such as oxygen concentration which will also affect the oxygen partial pressure.

[0128] When oxygen partial pressure is high and with the magnetic field produced at the interface, paramagnetic O*, oxygen will be held at the gas / media interface and have better opportunity to react with other gases such as SOXand NOXin addition to just CO2. However, if the oxygen partial pressure is low, the magnetic field at the interface may not be sufficiently strong to hold O* and may leave interface forming into O2 gas. In this situation, the catalyzed CO2 will be reduced by the H+ions produced from OER to form elemental C and water.

[0129] High oxygen partial pressure

[0130] CO2+ O* + H++ e ■ -> HCO3-

[0131] SO2+ 20* +2e- ^ SO42'

[0132] Low oxygen partial pressure

[0133] C02+ 4H++ 4e' -» C + 2H2O

[0134] Both NO and NO2 are paramagnetic molecules but NO2 is very weak paramagnetic as compared to NO. NO is therefore more responsive to the magnetic field effect as compared to NO2. Accordingly, NO takes the same reaction scheme as CO2.

[0135] On the other hand, NO2 has a “V” shape molecular structure making it more reactive with low excitation energy, thus it behaves similar as SOX.

[0136] N02+ O* + e ■ - N03-

[0137] 5. Summary of the gas removal working principle

[0138] The diagram of Fig. 5 summarizes the gas removal working principle of the multiplex catalytic method of this invention.

[0139] This invention makes possible to utilize these “waste” heat to remove CO2 / NOX / SOXby using the above DEMOP synergistic catalytic effect to remove the CO2 / NOX / SOXat waste heat temperature range. Under the circumstances that the invention DEMOP technique is carried out in moderate temperature range not high enough for thermal breaking of the gases, it has demonstrated that the multiplex catalytic technique is not a direct thermal gas breaking process.

[0140] In all the above DEMOP co-factors and reactions, waste heat energy can be completely utilized to remove CO2, NOXand SOXremoval without using high Mg2+concentration media. However, in the event of inadequate waste heat energy supply or higher CO2 removal rate is required, the CO2 / NOXremoval rate can be further increased by increasing the Mg2+ions concentration, also higher electro-catalytic energy from Mg2+ionization process and AMPE wave field treatment.

[0141] After the waste heat used for removing the CO2 / SOX / NOXpollutant gases, the exhaust or flue gas temperature is greatly reduced to close to or at atmospheric temperature before releasing to environment. After scrubbing, the waste heat temperature is further reduced to close to atmospheric temperature which has minimum negative environment impact compared with the typical temperature range of 250 ~ 400°C of industrial exhaust or flue gas. The negative environmental impact of the hot exhaust gas is therefore significantly reduced, and the fossil fuel power plants become more environmentally friendly.

[0142] Individual Gas conversion schemes and mechanisms

[0143] 1. CO2 conversion

[0144] The CO2 conversion can go via two possible pathways depending on oxygen partial pressure which determines the reaction pathway.

[0145] When oxygen partial pressure is low, O* in the OER reaction liberates readily. As a result, CO2 has lesser chance to react with O* at the gas / media interface but higher chance with H+, together with the electrons e- donated from the media, CO2 will undergo the following reaction.

[0146] IM ’ Catalyst

[0147] As can be seen, the above reaction is not a direct CO2 gas molecular bond breaking reaction.

[0148] The O* not taking part in the reaction will be converted to O2 in the following reaction.

[0149] The liberated O2 increases the O2 content in the scrubbed gases when CO2 is converted to elemental C. When oxygen partial pressure is high, due to the paramagnetic property of oxygen which is attracted to the weak magnetic field generated by the spraying action of the ionic MCH media, the excited O* will “wonder” at the gas / media interface. This increases the chances of the distorted CO2* to react with O* and / or H+. The reactions are given in the following.

[0150] CO2* + O* + H++ e' -» HCO3-

[0151] The diagram of Fig. 6 summarizes the various conversion pathways for CO2.

[0152] Although OH- is not paramagnetic, OH- can also take part under the duplex catalytic effect and undergo the following reaction with CO2 to form HCO3_ions at the gas / media interface.

[0153] H

[0154] Temperature effect in CO2 conversion

[0155] In the above process of OER to CO2 conversion reaction, if the available thermal energy from waste heat is high, the electron donating effect and the acid-base catalytic effect of the MCH media may be sufficient to perform the above CO2 conversion reactions by thermal energy activation even without the AM PE wave energy. Any additional AMPE wave energy will enhance the CO2 conversion performance and efficiency.

[0156] If the thermal heat energy from waste heat source is low or unavailable, high level of catalytic effect is required to activate the OER and CO2 conversion reaction, which can be enhanced by supplementing high concentration of Mg2+and / or metal ions in the MCH media as well as supplying the AMPE wave treatment. In practices, the higher Mg2+ions in the media can be produced by either ionizing the magnesium block using AMPE electro-catalytic Mg electrode ionization, DC pulse electro-catalytic ionization or non-pulsating DC electrolysis with or without time varying frequency. Alternatively, magnesium salts can be dissolved in the media to obtain the required Mg2+concentration.

[0157] 2. NOx conversion The property of NO is unique. It has unpaired electron at outermost electron layer, and it is also a diatomic free radical. The unpaired electron contributes to the paramagnetic property of NO and the free radical structure which has the tendency to snatch electrons, making NO susceptible to electron donating effects. With the DEMOP catalytic effect of the invention, NO gas can undergo the same reaction path as CO2 and the NO reaction path can be written in the following.

[0158] NO* + O* + e' -» NO

[0159] NO* + 20* + e ■ -> N03-

[0160] According to the similar reaction mechanisms, the elemental N2is formed under the condition of low oxygen partial pressure through the reduction reaction with H+ions and free electrons with the duplex catalytic effect, and NOX_ions are formed under high oxygen partial pressure.

[0161] NO2 is also a free radical with unpaired electron but has weak paramagnetic property. On the other hand, N02has a “V” shape molecular structure which is similar to the distorted structure of CO2 under the catalytic effect of MCH media, thus it is more reactive with low excitation energy. Accordingly, NO2 can undergo similar reaction as CO2 in the DEMOP technique. The reaction can be written as follows.

[0162] Moreover, the NOXremoval mechanism also involves the temperature effect similar to the case of CO2 conversion. AMPE wave treatment and high Mg2+ions concentration can be used to compensate for the low thermal waste heat energy supply.

[0163] 3. SOXconversion

[0164] Unlike CO2 and NO, SO2 exists as a polar covalent “V” shaped structure and has very low mean excitation energy. This makes SO2 react easily with water both in the liquid phase and at the interface. However, with the DEMOP effect, oxygen from OER creates oxygen crowding / shielding effect at the gas / media interface under the effect of the magnetic field, together with the saturation effect of carbonate and sulphate contents in the media, instead of diving straight into the media and react with water, SO2 can also react with O* to form SO42-ions at the interface in a similar reaction as NO2. The reaction at the gas / media interface can be written as follows.

[0165] S02*+ 20* +2e- ^ SO42' SOi*+ O* + 2e‘ ^ SO32'

[0166] It shall be noted that SO2 is not converted into the strong acid H2SO4 (sulfuric acid) in water in the above reactions, in view the reaction is conducted at the gas / media interface.

[0167] Moreover, SO3 can also be removed with the DEMOP technique so as to be converted to SO42-ions with reaction at the interface.

[0168] In this multiplex catalytic DEMOP activation invention, the reactions of SOXare independent from the conversion of CO2 to bicarbonates / carbonates ions. More specifically, the SOXcontent in the waste gas will not affect the reaction product of CO2. Thus it is clearly showed that the catalytic CO2 abatement mechanism of this invention is different from the non-catalytic process in prior art US 10,500,542 B2.

[0169] 4. Other liquid phase reactions

[0170] In addition to the above conversion reactions of CO2 / SOX / NOXaccording to the DEMOP technique of the invention, it shall be understood that other liquid phase reactions are still unavoidable during the pollutant gas scrubbing process. For example, some liquid phase reaction between water and CO2 / SO2 / NO2 will take place but they are minor side reactions in the context of the present invention. Therefore, only negligible amount of sludge is produced in the DEMOP scrubbing process. This eliminates the tedious handling of wastewater treatment plant and disposal of sludge as in other liquid phase reaction scrubbing process.

[0171] Method and system of the invention

[0172] The schematic diagram of a DEMOP multiplex catalytic system operable with a large marine diesel engine using high sulphur fuel oil (HSFO) is shown in Fig. 7 for illustration purposes. The DEMOP system can be applied to other plants such as boiler power plants, etc. with proper adaptation.

[0173] The objective of this invention is to remove high % of CO2 / NOXfrom engine exhaust or flue gas, with simultaneous removal of SOXto the level meeting low sulphur fuel emission requirements. In addition, the emission after DEMOP treatment must also meet marine pollution control requirements including discharge scrubbing wash water pH, poly aromatic hydrocarbon (PAH), nitrate, and turbidity requirement.

[0174] In the illustrated embodiment of the invention, the complete DEMOP scrubbing process consists of two major stages, i.e. closed loop (A) and loop (B). Preferably, loop (B) operates as a closed loop, but it has the option to operate as an open loop if required.

[0175] The closed loop (A) comprises a MCH media tank for containing, supplying the MCH media for circulating, and receiving the liquid after gas scrubbing treatment. The MCH media tank is equipped with AMPE wave treatment apparatus and heating device connected to waste heat source. The AMPE treated MCH media is drawn from the tank by a circulating pump to a spray nozzle arranged in a reaction chamber for creating a curtain screen of media mists. The MCH media can be further boosted by AMPE booster before spraying. Hot exhaust gas can be introduced to the reaction chamber from a bottom inlet. The exhaust gas can be further heated by other waste heat input before entering the reaction chamber if the temperature is low. The reaction chamber can comprise more than one levels in a vertical layer-by-layer configuration, with at least one spray nozzle arranged in each level. The exhaust gas passes through the multiple levels so as to be in contact with the media mist curtains, thus inducing the conversion reactions. The sprayed MCH media falls down to the bottom of each level of the reaction chamber and recirculates back to the media tank. The media tank also serves as a mixer for the preparation of the MCH media and has inlet ports for adding replenishment when required.

[0176] In certain embodiments, the first stage of closed loop (A) can operate independently without the second stage of loop (B) for the removal of CO2 / NOX / SOXgases.

[0177] The loop (B) can operate as either a closed loop similar to loop (A) or as an open loop without recirculating the sprayed media but discharging it after the scrubbing process. An external water source is also required for supplying water for the treatment. Another major difference of loop (B) with respect to loop (A) is that the gas removal operation is carried out in relatively low temperature, e.g. at near atmosphere temperature, because of the exothermic nature of the gas conversion reactions of the second stage. Accordingly, an inline cooler is arranged in the media recirculating path to control the temperature of the media. The media tank in loop (B) comprises electrical arrangements for ionization of Mg2+from magnesium blocks / electrodes, thus is an electro-catalytic Mg2+ionization tank. The media comprising Mg2+ions can be further treated with AMPE wave to enhance the electron donating effect for gas conversion reactions. The configuration of multi-level media spray in the reaction chamber in loop (B) is substantial same as in loop (A). The exhaust gas already treated in the reaction chamber of loop (A) is used as inlet gas into the reaction chamber in loop (B) for further pollutant scrubbing. The after-treatment liquid comprising high Mg2+content can be collected and concentrated to be used as replenishment material for the MCH media tank of closed loop (A). Operation of closed loop (A)

[0178] In the engine exhaust gas, the main pollutants include CO2 1 SOXI NOX, soot, unburnt hydrocarbons, and other minor pollutants. The exhaust gas is first passed through the closed loop scrubbing reaction chamber with one or more levels. When exhaust gas enters the closed loop scrubber, it encounters MCH media spraying curtain. Based on the principle of Ampere’s law, high-speed spraying action of high ionic / electron content MCH media creates a weak magnetic field at the immediate water curtain surface covering the cross section of the scrubber. A very fine mist nozzle cannot create the required magnetic field due to inadequate speed and the ions mass carried by the droplet. The purpose of producing the weak magnetic field in this invention is to attract the paramagnetic gases O2, NO, and NO2 to the water surface to react with the MCH media at the gas / media interface.

[0179] With the strong electron donating effect of AMPE wave treatment, electrons are donated from the treated MCH media to the gas due to the electron donating potential gradient at the media / gas interface. With the large surface area at the media / gas interface created by the media curtain in the spraying action, large number of electrons cross the interface and creates the oxygen evolution reaction (OER) as described above.

[0180] Due to the OER reactions and the paramagnetic property of oxygen, the OER cascades down series of reactions as described in the above sections, converting CO2 / NOX / SOXto either bicarbonate / carbonate, nitrate, and sulphate ions, elemental C and N2depending on the oxygen partial pressure in the exhaust gas. In the first two levels in closed loop (A), due to the reactivity of SOXis much higher than CO2 / NOX, majority or complete removal of SOXcan take place. If there is sufficient waste heat energy, up to approximately 20-40% of CO2 / NOXcan be removed in closed loop (A).

[0181] The MCH media, after contacting the exhaust gas in closed loop (A), is not discharged to the environment. Instead, it is recirculated back to the media tank for “recharging” by AMPE wave treatment. Since scrubbed media in closed loop operation is not discharged to the environment, there is no environmental issue of discharge water.

[0182] In the closed loop media tank, the media is first mixed according to the media specification, which is discussed in the subsequent section. In scrubbing operation, the media pH and alkalinity may be reduced due to the minor liquid phase reactions. The media therefore requires replenishment of media which can be dosed in by the external dosing mixer or from the concentrated scrubbed media from closed loop (B).

[0183] CO2 / NO removal in closed loop (A) generally takes place when exhaust gas temperature entering the scrubber is above 250 °C, although some minor removal begins to take place when temperature reaches 200 °C. More significant gas removal takes place when exhaust gas temperature is higher than 300 °C, which is the optimum temperature of the invention. More preferably, better gas removal rate can be achieved when exhaust gas temperature is above 330 °C.

[0184] The waste heat in the exhaust gas is utilized for the SOX / CO2 / NOXremoval. Other waste heat sources such as from boilers, charge air cooler, exhaust gas before turbo charger etc. can all be utilized if available. The heat energy can also be directed to heat the MCH media either in the tank or in the circulation lines, thus the sprayed media is also at elevated temperature for improving the reactivity of the gas conversion reactions.

[0185] CO2 and NOXgas removal are directly proportionate to heat energy available in the closed loop reaction chamber. On the other hand, SOXare less dependent or independent on temperature and heat energy. However, the removal of all three gases SOX / CO2 / NOXcan always take place simultaneously.

[0186] If no further CO2 / NOXremoval is required after closed loop (A), the treated gas after the closed loop (A) containing water mist will pass through a mist catcher to remove the mist and discharge the treated gas to atmosphere.

[0187] After the closed loop (A), the gas temperature is greatly reduced and there will be inadequate supply of waste heat energy in closed loop (A) if higher percentage of CO2 removal is required. In such a heat deficient situation, an additional stage, i.e. loop (B) can be installed after the closed loop (A) to perform further CO2 removal. In loop (B), remaining SOX, CO2 and NOXcan still be further removed without the heat energy effect required via exothermic reaction process.

[0188] Operation of loop (B)

[0189] In loop (B), seawater is drawn into the electro-catalytic Mg2+ionization tank of loop (B) for treatment. The main purpose of the ionization treatment is to produce the free Mg2+ions electro-catalytic effect, instead of producing alkaline water containing hydroxyl ions as an alkaline media to neutralize the acid from scrubbing. In other words, the drawn seawater is converted to a proper MCH media after the ionization treatment. The introduced “free” Mg2+metal ions act as catalyst and provide catalytic reaction sites for subsequent conversion reactions.

[0190] In loop (B) treatment, high concentration of “free” magnesium ions is introduced into the seawater preferably using electro-catalytic ionization methods. Alternatively, addition of magnesium-based chemicals can be utilized as well. The Mg2+electro-catalytic ionization can be achieved by AMPE pulse ionization, DC pulse wave / static DC ionization, with or without time varying. Pulsating field generated by the AMPE wave or DC pulses can also be created inside the electro-catalytic ionization tank to energize the seawater vibration energy and further excite the Mg2+to improve the CO2 / NOXscrubbing efficacy.

[0191] Loop (B) is operated in conjunction with the closed loop (A). During operation, scrubbed gas from closed loop (A) is directed into the reaction chamber of loop (B), which gas is almost SOXfree and the gas temperature is low. This creates a good condition for the exothermic CO2 / NOXremoval process in loop (B). This exothermic process is mostly performed by the strong electron donating potential catalytic effect at the interface, also the base catalytic effect of the Mg2+ions to create the H+and e- from the strong OER reactions for the exothermic CO2 / NOXreductive reaction which produce elemental C and N2. The vibration energy effect from AMPE treatment or pulse treatment also contributes to the electro-catalytic effect.

[0192] In loop (B), the oxygen partial pressure is low, and most O* are converted to O2 which is highly exothermic and the overall reactions in loop (B) is exothermic.

[0193] Since the reaction of loop (B) is exothermic, it does not require waste heat energy for the reaction to take place. Instead, a cooler is installed in the media recirculating line to control the temperature, in order to ensure that the media temperature is sufficient low such that it does not degrade exothermic reactions in the loop (B), especially in closed loop operation mode.

[0194] While the waste heat is the main contributing factor for the gas scrubbing of this invention for closed loop (A) operation, the oxygen partial pressure of the exhaust gas is the main factor that determines whether the CO2 can go to elemental C conversion reaction or bicarbonate / carbonate reactions. Since oxygen partial pressure in an exhaust gas system is determined by the oxygen concentration and back pressure, therefore, the oxygen concentration in the exhaust gas and the scrubber back pressure shall be as low as possible in order to obtain elemental C in loop (B) treatment. This can be achieved by lowering the gas flow speed through enlarging the scrubber diameter to reduce the back pressure created by the high gas flow speed, or to reduce the excess air supply in the fuel combustion process in the engine which produces the exhaust gas.

[0195] The reaction sites of the CO2 1 NOXreduction catalytic conversion with OER are on water spray curtain water droplet surface with the magnetic field effect created by the spray action. In all the feeding lines supplying media to the spray nozzle in both loops, in line AMPE treater booster can be installed in each line to boost up the electro-catalytic effect, hence increasing the gas scrubbing efficacy.

[0196] After water contacting with CO2 / NOXin loop (B) and conversion reactions take place, scrubbed water is relatively clean due to majority of the solid impurities and SOXwere removed in closed loop (A). However, the scrubbed water of loop (B) may contain unreacted Mg2+and magnesium compounds created by the side liquid phase reaction in the Mg2+ionization process. The pH of the water after scrubbing is typically higher than pH 9. The scrubbed water may be centrifuge separated and the concentrated solute may be fed into closed loop (A) as MCH replenishment material. This is achieved by using either cyclone separator to concentrate the magnesium compounds in the scrubbed water of loop (B) and feeding this concentrated scrubbed water containing magnesium compounds into the media tank of closed loop (A) as MCH media feeds.

[0197] In closed loop operation of loop (B), the scrubbed water from the reaction chamber is recirculated back to the ionization tank. Seawater can be intermittently drawn as supply of the media to compensate for the media loss such as carried away by the emission gas. Due to the overall closed loop (B) reaction is exothermic, temperature rise of the recirculating water will affect the performance of the reaction. Cold water from the open sea or waterway may be utilized to cool the media temperature via heat exchanger to improve the CO2 conversion when the loop (B) is operated as closed loop.

[0198] Due to temperature control is required when operating closed loop (B), loop (B) can also be operated as open loop if required. Since the majority of the impurities, contaminants are taken out in closed loop (A), scrubbed water from closed loop (B) is quite clean and non-acidic. In desirable conditions, discharge valve to sea may be open and loop (B) can operate as an open loop. The scrubbed water after centrifuge treatment can be discharged without causing environmental issue. If necessary, a filtration system may be installed to remove the larger particulate before discharging to sea. On the other hand, during open loop (B) operation,

[0199] In some cases, the seawater having high salinity may not be available such as when vessel is operating in freshwater river, lake or even in Baltic Sea where the water has very low conductivity. When the water conductivity is low, high power is required to produce the ionized Mg2+ions. In such a situation, salts may be added to increase the conductivity and loop (B) can be operated in closed loop. Due to the closed loop operation, the quantity of salt needed to correct the conductivity is low. When the salt content is increased to seawater level, less power is required to do the Mg2+ionization process.

[0200] The Multiplex catalytic media and its preparation, treatment, sustenance, and spraying

[0201] The MCH media is an ionic solution of dissolved Mg2+ / M+ions and CO32- / HCO3- ions (MCH). The media is rich in Mg2+ions and HCO3- / CO32-ions in dissolved solution form. This media is different from MgCO3powder solution used in prior art such as US 8,529,855 B2. MgCO3has very low solubility in water, and it exists mostly as a mixture of MgCO3solid powder and water, instead of a solution of Mg2+ions and CO32-I HCO3- ions.

[0202] Although the MCH as described above is an ionic solution of dissolved Mg2+ / M+ions and CO32- / HCOs- (MCH), the positive and negative ions in the solution can also be replaced by other cations and anions. Common cations such as K+, Na+, Zn2+, Ca2+, and anions such as PO43-, SO42-, Cl-, Br etc. may be used. In principle, the ORP potential of the MCH media must be sufficiently negative to transfer electron to the gas at gas / media interface, and the cations / anions could bend the O=C=O bonds to function as MCH media.

[0203] In this invention, the MCH media comprising Mg2+ions and CO32- / HCO3- ions is the ideal media useful as a multiplex catalytic fluid media. This is due to the following unique properties of the MCH ionic solutions.

[0204] • The Mg2+and CO32- / HCO3- ions of the MCH media can act as catalyst as it can bend or distort the stable linear molecular structure of CO2 / NO to more unstable molecular structure.

[0205] Compared with sodium, magnesium not only has greater number of delocalized electrons, but it also has greater attraction from the magnesium nuclei. Magnesium atoms also have a slightly smaller radius than sodium atoms, such that the delocalized electrons are closer to the nuclei. Each magnesium atom has twelve nearest neighbors in the crystal structure rather than sodium’s eight. However, Na+can still be used as catalytic ions although it is weaker than Mg2+.

[0206] • The MCH media is responsive to AMPE wave treatment and produces strong electron donating effect and high stretching and scissoring O-H bond vibration energy after treatment. This vibration energy and electron donating effect from the treated media can be transferred at ultrafast rate at the gas / media interface when the media is in contact with the gases, catalyzing and lowering the temperature required to break the gas bonds.

[0207] • The MCH media can accommodate very high alkalinity capacity and maintain suitable operating pH range with good buffering performance.

[0208] The anions in the MCH solution are good buffering agents. The common and majority of buffering alkaline ions in water are HCO3_ / CO32- / OH“. High OH“ exists at high pH (P alkalinity) which promote liquid phase reaction, thus is less desirable as compared with HCO3_ / CO32-. Carbonate and bicarbonate function as a buffer pair and are preferred in MCH solution, although OH- is usable in certain embodiments.

[0209] • The Mg2+ions and HCO3_ / CO32-ions component content of the MCH media is reversible and mutually convertible dependent on the media pH and temperature. Heat from the exhaust gas can shift more HCO3_to CO32-and pH will shift slightly to be more acidic. When the media is cooled to lower temperature, more CO32-ions will shift to HCO3_and increase the pH slightly.

[0210] HCO3- O H++ CO32

[0211] Moreover, pH will also affect the form and composition of Mg2+and HCO3_ions. At pH 7~8, MgCO3is mostly dissociate and present as Mg2+ions and HCO3_ions. At pH > 8, MgCO3is mostly dissociate and present as Mg(HCO3)2 compound. In view Mg2+is important in bending the CO2 gas molecules, the optimum pH operating range of the MCH media for the ions content reversible operation is 7 to 8.5.

[0212] Th slightly alkaline operation condition makes the ionic solution of Mg2+and HCO3_I CO32-ions easy to use and operate efficiently in scrubbing process conditions. Meanwhile, the media also possess strong buffering capacity at this pH range.

[0213] • The pH level in the media can be partially corrected by the free electron generated in the media by the AMPE wave to neutralize the H+ions.

[0214] Alternatively, the pH can also be corrected by adding alkali material (OH ) to neutralize the H+ions.

[0215] The HCO3- 1 CO32-ions in the media can be partially replenished by the scrubbed products of CO2 gas. When CO2 is dissolved in water as carbonic acid, it produces H+and HCO3_. With the DEMOP reactions using the electrons produced by the AMPE wave treatment, the electron will neutralize the H+and further convert CO2 to HCO3- / CO32-. The reaction products replenish the bicarbonate / carbonate buffer of the MCH media thus reducing the replenishment by adding alkali pH materials.

[0216] Alternatively, dilute NaOH can be used to scrub the final cleansed exhaust gas to produce the HCOs- / CO32-ions in the media and then mix with MgSO4 for media replenishment. Or, MgO can be added in final scrubbed solution and then mix with NaHCO3to replenish the media and correct the pH.

[0217] For closed loop (A), the criteria for the mixed MCH media solution include the following:

[0218] 1 ) The pH of the initial media mixture before treatment should not be higher than pH 9.5, and the preferred pH range is between 8.5 and 9.5.

[0219] 2) The pH during operation shall be maintained at no less than 7.5, and the preferred pH range is 7.5 to 8.5.

[0220] 3) The initial total (bicarbonate + carbonate) alkalinity should be more than 20,000 ppm, preferably more than 25,000 ppm.

[0221] 4) The total (bicarbonate + carbonate) alkalinity during operation shall be maintained at more than 15,000 ppm, preferably more than 20,000 ppm.

[0222] 5) The preferred magnesium ions concentration shall be more than 6,000 ppm in the initial media, and more than 4,000 ppm during operation.

[0223] The media solution of dissolved Mg2+ / M+ions and CO32- / HCO3- ions can be prepared by any conventional means to produce an aqueous solution based on standard chemistry textbook teachings and practices. These preparation methods include but not limited to the following:

[0224] • Mixing magnesium salts with other bicarbonate salts such as sodium bicarbonate to produce a magnesium ions and bicarbonate / carbonate ions rich solution. Calcium salts may be used but cautions shall be taken to avoid hard scale formation.

[0225] • Using magnesium oxide, magnesium hydroxide, low concentration of sodium hydroxide to react with carbon dioxide.

[0226] Using AMPE, DC or DC component wave to electrolyze magnesium electrode to produce Mg2+ions in the media via electrolysis reactions. The above media preparation methods can be used independently or in combination. For example, media can be first prepared by mixing magnesium sulfate with sodium bicarbonates in the tank before start up, and DC electrolysis of magnesium electrode or MgO / Mg(OH)2can be subsequently added during operation.

[0227] Inside the MCH media tanks, the media is continuously treated by the pulsating field generated by the AMPE wave (with or without time varying) using inductor coils and / or capacitors treatment as shown in the diagram of Fig. 8. It can also be used in parallel with magnesium electrode DC electrolysis as mentioned above. Accordingly, the media can be prepared and replenished in the same tank.

[0228] In closed loop operations, once the MCH media recirculates back to the media tank, it is recharged by the AMPE wave inductor and / or capacitance field in the tank again with the electric circuit configuration as shown in Fig. 8. The AMPE capacitive charging with capacitive electrodes and AMPE inductive charging with inductor coils can be performed on the MCH media simultaneously or individually.

[0229] In open loop operations, the system takes water from open sea, lakes or waterway into the tank. Magnesium blocks are arranged and distributed evenly in the tank as electrodes, and the magnesium blocks are ionized by the AMPE pulsed wave or DC pulsating wave with or without time varying for replenishing Mg2+ions. The electric circuit configuration for the AMPE and pulse wave treatment are shown respectively in the arrangement in the diagram shown in Figs. 9A-B.

[0230] In some cases, conductivity of the newly drawn water may be too low, and it will increase the power consumption of the Mg2+ionization. In such situations, salts can be added to increase the conductivity and to reduce the power consumption. The preferred water conductivity is more than 50 ms / cm.

[0231] In the pollutant gas scrubbing process, the MCH media is sprayed in the scrubber tank as fine mist and micro droplet to create the magnetic fields and enact the gas / media interface reactions with the gases. Although the sprayed media is collected at the bottom of the tank, part of the spray water and MCH ionic media may still be carried away in the treated gas and discharged into the atmosphere. A mist catcher can be installed after the scrubber tank to minimize the loss of media, especially when only closed loop (A) is used. Nevertheless, the mist catcher is never perfect and certain amount of mist loss together with the magnesium, carbonate and bicarbonate ions loss shall be expected and replenishment of MCH media is also necessary for closed loop only system.

[0232] If the media volume is only topped up just by adding water (seawater or freshwater) for closed loop operation, the carbonate / bicarbonate and magnesium concentration in the scrubbing media will be depleted and replenishment of new Mg2+ / HCO3_ / CO32-ions or corresponding solutes will be needed.

[0233] For system operated with closed loop (A) and open / closed loop (B), the discharge water from the open / closed loop (B) may be concentrated using a cyclone separator or similar decanter arrangement to concentrate the solutes in the discharge water. Such solute concentrates comprising magnesium from the cyclone is then fed into the closed loop (A) as make up media. This will reduce the amount of replenishment needed in the closed loop (A).

[0234] In summary, the pollutant gases abatement concept and mechanism of this DEMOP invention utilizes the following technologies not mentioned in prior art, thus achieves the following advantageous effects.

[0235] 1 . Using the multiplex catalytic effects provided by the MCH media, the AMPE wave treatment, the magnetic field created by spray action, and the waste heat energy.

[0236] 2. Using the Oxygen Evolution Reaction (OER) to create energized oxygen O* and H+ions at the gas / media interface to react with CO2 / NOX / SOXto produce either elemental C, N2, or ions of CO32' I HCO3- 1 SO32' I SO42’ I NO2- 1 NO3-.

[0237] 3. Using the natural electro-catalytic electron donating effect and acid-base catalytic effect of the MCH media to activate the above OER reaction. Such duplex catalytic effect is especially achieved by the use of high concentrations Mg2+in the MCH media in open loop operation.

[0238] 4. AMPE wave treatment is also used to enhance the electro-catalytic electron donating effect to activate the above OER reaction. The waveform and generation circuit design of the AMPE wave are also different from prior arts.

[0239] 5. Spraying the MCH media of high ions content at high speed to generate weak magnetic field on media spray surface to provide reaction sites with high concentration of reactants. Energized oxygen O* and NOXare attracted because their paramagnetic property to the magnetic reaction sites on the gas / media interface for reaction with other gases.

[0240] 6. Reaction pathways of CO2 / NOX / SOXcan be controlled using oxygen partial pressure in combination with the temperature effect to accommodate the two-stage pollutant removal process. 7. Using the otherwise “waste” heat energy to facilitate CO2 I NOXI SOXgas conversion reaction at exhaust gas temperature range in the first stage closed loop (A) process.

[0241] 8. The unique combination of closed and open loop systems to achieve high CO2 / NOXand SOXremoval also resolves the discharge water environmental pollution issue.

[0242] 9. The use of Mg2+ionization to increase the media electro-catalytic and acid-base catalytic effect to further remove CO2 / NOXin the absence of waste heat in the second stage open loop process.

[0243] 10. The discharge water after concentrating the solute is used as replenishment media for closed loop (A) for maintaining media pH and alkalinity contents.

[0244] 1 1. The MCH media also possesses unique reversible property of the Mg2+and carbonate / bicarbonate ions based on pH and temperature for affecting the gas removal reaction conditions.

[0245] Preferences and options for a given aspect, feature or parameter of the invention should, unless the context indicates otherwise, be regarded as having been disclosed in combination with any and all preferences and options of all other aspects, features and parameters of the invention.

[0246] While the embodiments described herein are intended as an exemplary system and method, it will be appreciated by those skilled in the art that the present invention is not limited to the embodiments illustrated. Those skilled in the art will envision many other possible variations and modifications by means of the skilled person's common knowledge without departing from the scope of the invention, however, such variations and modifications should fall into the scope of this invention.

Claims

AMENDED CLAIMS received by the International Bureau on April 11 , 2025 (11 .04.2025)

1. Method for the simultaneous removal of pollutant gases CO2 / NOX / SOXfrom exhaust gas, comprising the steps of: preparing a media comprising magnesium ions and carbonate / bicarbonate ions, treating the MCH media by an alternating multi-pulse embedded (AMPE) wave for enhancing the electron donating effect, wherein the AMPE wave comprises an alternating main AC wave and at least two unidirectional DC pulses embedded in each half cycle of the main AC wave, and spraying the media through high pressure nozzle onto the exhaust gas to convert and remove the pollutant gases, wherein pollutant gas removal from hot exhaust gas is performed with AMPE wave treated MCH media in a first stage operation so as to remove SOXand part of CO2 and NOX.

2. The method according to claim 1, wherein the media is an aqueous solution comprising dissolved Mg2+ions and COs2- / HCOs" ions.

3. The method according to claim 2, wherein the media further comprises other metal cations such as K+, Na+, Zn2+, Ca2+, and / or other anions such as PC>43’, SC>42’, Cl", Br.

4. The method according to any one of claims 1 to 3, wherein the media spray activates oxygen evolution reaction (OER) which converts H2O and OH- to O*, H+and e- at the gas / media interface under the catalytic effect of the media.

5. The method according to any one of claims 1 to 4, the MCH media possesses electron donating electro-catalytic effect and acid-base catalytic effect.

6. The method according to any one of claims 1 to 5, wherein the AMPE wave has one or more of the following features:(1) the AMPE wave has a net root mean square voltage equals to zero;(2) a full cycle of the AMPE wave consists of a positive half cycle and a negative half cycle whose shapes are identical to each other but in the opposite voltage direction;(3) the main AC wave and / or the embedded DC pulses are independently time varying or non-time varying;(4) the polarity alternating interval of the main AC wave is in the range of lxlO-4second to a few seconds;(5) the number of unidirectional DC pulse in each half cycle is in the range of 2 to lxlO5pulses;(6) the AMPE wave creates free electrons and / or elevates bond vibration of water;(7) the AMPE wave is applied by at least one capacitive electrode pairs or inductor coils inside the media.

7. The method according to any one of claims 1 to 6, further comprising the step of: generating Mg2+ions in the media via ionization treatment using magnesium electrodes.

8. The method according to any one of claims 1 to 7, wherein the high-speed spraying of the media creates a magnetic field for attracting, retaining and energizing the paramagnetic oxygen O* at the media interface generated from OER to react with the pollutant gases.

9. The method according to any one of claims 1 to 8, further comprising the step of: controlling the oxygen partial pressure of the exhaust gas to control the conversion pathway of the pollutant gases, particularly CO2 and NOX.

10. The method according to any one of claims 1 to 9, wherein a second stage operation is performed on the treated exhaust gas from the first stage operation at lower temperature with higher Mg2+concentration media than in the first stage operation.

11. The method according to any one of claims 1 to 10, further comprising the step of: replenishing the media by collecting and concentrating the scrubbed water and recycling the concentrated solute for preparing the media.

12. System for the simultaneous removal of pollutant gases CO2 / NOX / SOXfrom exhaust gas, comprising: a first stage of closed loop comprising a media tank, a reaction chamber in which a high pressure spray nozzle is arranged, and recirculating means of the media, wherein the media comprising magnesium ions and carbonate / bicarbonate ions, and the media is sprayed through the high pressure nozzle onto the exhaust gas to convert and remove the pollutant gases, and further comprising means for generating AMPE wave to treat the media in the media tank and / or in the recirculating lines before the spray nozzles for enhancing the electron donating effect of the media, wherein the AMPE wave comprises an alternating main AC wave and at least two unidirectional DC pulses embedded in each half cycle of the main AC wave, wherein the pollutant gas removal in the first stage is performed on hot exhaust gas with AMPE wave treated MCH media so as to remove SOXand part of CO2 and NOX.

13. The system according to claim 12, wherein the first stage reaction chamber comprises more than one levels in a vertical layer-by-layer configuration, wherein at least one spray nozzle is arranged in each level.

14. The system according to claim 12 or 13, wherein the first stage of closed loop further comprises heating device for heating the media and the reaction chamber, preferably the heating device is connected to waste heat source.

15. The system according to any one of claims 12 to 14, wherein the media tank serves as a mixer for the preparation of the media and has inlet ports for adding replenishment when required.

16. The system according to any one of claims 12 to 15, further comprising: a second stage of open or closed loop operated in conjunction with the first stage, the second stage loop comprises an Mg2+ionization tank, a reaction chamber and recirculating means, wherein the recirculating means comprises an inlet valve for drawing from external water source and a discharge valve for discharging scrubbed water.

17. The system according to claim 16, wherein the second stage further comprises a cooler arranged in the recirculating path to control the temperature of the media.

18. The system according to claim 16 or 17, wherein second stage reaction chamber comprises more than one levels in a vertical layer-by-layer configuration, wherein at least one spray nozzle is arranged in each level, and the second stage reaction chamber has larger diameter than the first stage reaction chamber.

19. The system according to any one of claims 16 to 18, wherein the Mg2+ionization tank comprises means for ionization of magnesium electrodes, preferably by AMPE pulse ionization, DC pulse wave or static DC ionization.

20. The system according to any one of claims 16 to 19, wherein the pollutant gas removal in the second stage is performed on the treated exhaust gas from first stage operation at lower temperature with higher Mg2+concentration media than in the first stage operation.

21. The system according to any one of claim 12 to 20, further comprising: means for replenishing the media by collecting and concentrating the scrubbed water from the second stage and recycling the concentrated solute for the preparation of the media in the first stage.

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