Novel and highly cost effective technology for capture of industrial emissions without reagent for clean energy and clean environment applications

A very cost effective and energy efficient technology of capturing industrial emissions (mercury (Hg) and its oxides, sulfur dioxide (SO2), sulfur trioxide (SO3), nitrogen dioxide (NO2), carbon dioxide (CO2), nitrous oxide (N2O), nitric oxide (NO), carbon monoxide (CO)) contained in the flue gas from coal and natural gas fired power plants (all older and newer versions), cement plants and industrial plants in general, each component separately from each other and in the form of industrially useful product that can be conveniently stored, and thus to prevent or reduce/mitigate global warming/climate change/environmental pollution/health effects arising due to such gaseous emissions from the said industries into atmosphere & environment and thus to ensure clean air/environment, using or requiring no chemical reagent and no external cryogen, but only a small fraction of electrical power from the output power of the plants or using the said needed electrical power from any other source and fixed amount of water that can be repeatedly used during the capture process, comprising the steps of :

• a) Generation of auxiliary electrical power using the heat of the flue gas using a turbine that can use anhydrous ammonia contained in an ammonia super-heater, which is heated by the heat of the flue gas, the heat absorption of the said super heater being enhanced by coating on its surface a film of materials with high heat absorptivity and low emissivity and its placement in an insulated chamber containing ceramic filters to filter out the ashes & soot of the flue gas;
• b) passing the flue gas through ceramic filters, fabric filter, ESP (Electrostatic precipitator), which capture partially the heat, the ashes, soot/floating particulates and partially the mercury and its oxides, with arrangement for removal of the ashes;
• c) reheating the ammonia after the turbine work by passing through the fabric filter & ESP in reverse direction;
• d) using successive compressions to specified pressures, successive cooling through use of specialized heat exchangers and successive adiabatic expansions of the said flue gas, throttling of liquefied CO2 when necessary;
• e) further cooling of the nitrogen (N2) gas of the flue gas to a few (about 1 to 2) degrees above its boiling point (−196° C.) for using the said cold N2 gas (by flowing it in reverse direction) to cool the flue gas at different steps, for individual capture (separation) of the components;
• f) cooling in process 1d) being accomplished by (i) passing adiabatically compressed flue gas through heat exchangers containing special tubes immersed in fixed amount of water, for capture of components with boiling points above 0° C., the water being cooled by flow of said cold nitrogen gas through turns of tubes that surround the turns of tubes of the flue gas and radiative cooling arrangement, if the latter is needed;
• g) by passing adiabatically compressed flue gas, for individual capture of its components with boiling points below 0° C., through heat exchangers containing (i) metal chips/or conducting pebbles on racks surrounding the turns of tubes carrying said cold nitrogen gas which in turn surrounds the turns of tubes carrying the said flue gas, all being embedded in the chambers of the said heat exchangers and (ii) helium gas that provides good heat conduction (exchange) between the flue gas tubes and the tubes carrying cold nitrogen gas and the pebbles/metal chips, which are cooled by the said cold nitrogen gas which has temperature just about 2 degree C. above its boiling point (−196° C.) produced through the third stage turbine expansion, following the step of capture of nitric oxide of the flue gas towards the end of a process cycle;
• h) superior control of cooling the flue gas to desired temperatures as required for capture of individual components of the flue gas, each separately through methods of claim 1f) & 1g), compared to heat exchanger chamber where cold nitrogen gas directly surrounds the said turns of the flue gas tubes as the nitrogen gas directly enters through the inlet port and leaves through the outlet port of the chamber;
• i) repeating the compression, cooling (as in (ii) of 1e) and expansion successively for 15 to 20 stages, or as necessary, depending on the initial flue gas temperature and concentration of the components;
• j) fractionally liquefying or freezing each component of emissions at specific temperature and pressure using the processes of claims 1a) to 1i) for cooling the flue gas and using controlled amount of the said super cooled nitrogen gas in successive stages of compression, cooling and expansion;
• k) using methods to control the temperatures of the chambers to specified temperatures by control of the very cold nitrogen gas obtained by method of claim 1e) and through use of specialized heat exchangers of claim 1f) & 1g), standard temperature controller and standard flow controller device;
• l) using methods of special coating to prevent corrosion of flow tubes, compressors, etc. due to corrosive components of the flue gas and using flow tubes of special materials to ensure very good thermal conduction of heat between hot flue gas and the cold nitrogen gas carrying flow tubes which are all embedded in the said chambers of heat exchangers;
• m) utilizing the work generated during turbine expansion (near the end of a cycle) of compressed N2 for aiding compression of flue gases in successive previous stages employing the n-stage compressors and thus to increase energy efficiency of the whole capture process;