Low emissions diesel system and method

Abstract

The invention is embodied in a diesel system for reducing diesel particulate matter (DPM) emissions particularly in underground diesel engine operations, comprising, in combination, a supply of synthetic paraffinic diesel fuel having substantially no sulfur, aromatics and nitrogen content and formulated to greatly reduce DPM levels in the engine exhaust emissions relative to conventional diesel fuels, and other exhaust emissions processing apparatus preferably forming an aqueous filter constructed and arranged to form a water bath for all exhaust gas output from the engine and including in the water bath a preselected significant quantity of a low foaming wetting composition having a high affinity for hydrocarbons. The invention is further embodied in the method of reducing diesel emission contaminants including providing a supply of synthetic diesel fuel having a negligible sulfur, aromatics or nitrogen content, pre-filtering the diesel fuel, and removing DPM from exhaust gases by filtration.

1 . A diesel emissions control system for removing diesel particulate matter (“dpm”) from diesel engine exhaust comprising, in combination, a supply of paraffinic-type synthetic diesel fuel for the diesel engine, an aqueous filter apparatus in the emissions output from the diesel engine and being constructed and arranged to form a water bath through which all “dpm” laden exhaust gases must pass before discharge to ambient, the water bath of said aqueous filter apparatus having a major water constituent and a minor constituent amount of a super-wetting agent having a relatively high affinity for hydrocarbons.  
   
   
       2 . The emissions control system of  claim 1 , in which said synthetic diesel fuel has a Cetane rating in the range of about 60 to 80.  
   
   
       3 . The emissions control system of  claim 2 , in which said Cetane rating is in the range of about 65 to 75.  
   
   
       4 . The emissions control system of  claim 1 , in which said synthetic diesel fuel is characterized by having substantially no sulfur, aromatics or nitrogen content.  
   
   
       5 . The emissions control system of  claim 4 , in which the synthetic diesel fuel has a sulfur content of less than 1.0%.  
   
   
       6 . The emissions control system of class  4 , in which the synthetic diesel fuel has an aromatics content less than 1.0%.  
   
   
       7 . The emissions control system of  claim 4 , in which the synthetic diesel fuel has a nitrogen content of less than 1.0%.  
   
   
       8 . The emissions control system of  claim 1 , in which the synthetic diesel fuel is formulated to burn with a substantially lower “dpm” content in emission gases than in conventional diesel fuels.  
   
   
       9 . The emissions control system of  claim 8 , in which the lower “dpm” content is in the range of 20 to 40%.  
   
   
       10 . The emissions control system of  claim 1 , in which the synthetic diesel fuel is a linear paraffin-linear olefin fuel formulated to have a Cetane rating in the range of 60 to 80 and characterized by having negligible amounts of sulfur, aromatics and nitrogen.  
   
   
       11 . The emissions control system of  claim 1 , in which said aqueous filter apparatus comprises a gas scrubber tank filled to a predetermined level with said water bath, said emissions output having an exhaust gas inlet pipe and gas diffusing means below the level of said water bath in said tank for dispersing exhaust gases throughout the water bath.  
   
   
       12 . The emissions control system of  claim 11 , in which said exhaust gas inlet pipe includes liquid aspirating inlet means below the water bath level for inducing a flow of the water bath liquid into the inlet pipe upstream of the gas diffusing means.  
   
   
       13 . The emissions control system of  claim 11 , in which said gas scrubber tank has an exhaust discharge outlet to ambient, and wherein said gas diffusing means comprises vertical baffle means disposed in said gas scrubber tank for producing intermixing flow paths of exhaust gases through the water bath.  
   
   
       14 . The emissions control system of  claim 13 , in which said baffle means comprises at least one vertical baffle plate forming a vapor barrier above the water bath and having its lower end positioned in the water bath.  
   
   
       15 . The emissions control system of  claim 13 , in which said baffle means comprises a horizontal baffle plate extending across the scrubber tank above the discharge level of the gas diffusing means.  
   
   
       16 . The emissions control system of  claim 11 , in which said exhaust gas inlet pipe is substantially larger than the emissions output delivery thereto.  
   
   
       17 . The emissions control system of  claim 16 , including liquid aspirating means for inducing the flow of water bath liquid into the exhaust gas inlet pipe, and wherein the gas diffusing means is constructed and arranged to accommodate the intermixing of exhaust gases with the aspirated water bath liquid without creating any substantial back pressure on the diesel engine.  
   
   
       18 . The emissions control system of  claim 13 , in which said gas scrubber tank has a relatively large size holding a water bath in the volumetric range of 26 to 90 gal.  
   
   
       19 . The emissions control system of  claim 13 , in which said gas scrubber tank has a relatively small size holding a water bath in the volumetric range of 3 to 10 gal., and a liquid supply source of blended water and super-wetting agent constructed and arranged for maintaining the water bath level in said scrubber tank.  
   
   
       20 . The emissions control system of  claim 1 , including in combination, a diesel fuel pre-filter constructed and arranged upstream of the diesel engine for removing non-fuel contaminates from the synthetic diesel fuel for filtering non-combustible contaminates and providing a substantially totally-combustible synthetic diesel fuel supply to the engine.  
   
   
       21 . The emissions control system of  claim 11 , in which said gas scrubber tank has an exhaust discharge outlet leading to ambient and, in combination therewith, a final gas filter constructed and arranged to filter substantially all residual DPM material from the cooled and cleaned exhaust gases passing from the gas scrubber tank.  
   
   
       22 . The emissions control system of  claim 1 , in which said super-wetting agent comprises a chemical hydrocarbon cleaner including at least one component selected from the group consisting of detergents, soaps, surfactants and mixtures thereof, and a defoaming agent.  
   
   
       23 . The emissions control system of  claim 22 , wherein the chemical hydrocarbon cleaner comprises at least one surfactant selected from the group consisting of anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants and mixtures thereof.  
   
   
       24 . The emissions control system of  claim 22 , wherein the super-wetting composition further comprises an organic solvent.  
   
   
       25 . The emissions control system of  claim 22  wherein the super-wetting agent comprises: 
 a chemical hydrocarbon cleaner comprises ethoxylated nonylphenol nonionic surfactant and a soap formed by saponifying a tall oil fatty acid with monoethanolamine;    an organic solvent comprising dipropylene glycol methyl ether;    a coupling agent comprising tetrasodium EDTA; and    a defoaming agent comprising a silicone-based antifoam.    
   
   
       26 . A synthetic diesel fuel for low emissions control in Class  32  diesel engine machinery, said fuel having a Cetane rating in the range of 60 to 80 and the following properties: 
 (1) a sulfur content of less than 1.0%    (2) an aromatics content of leas than 1.0%    ( 3 ) a nitrogen content of less than 1.0%.    
   
   
       27 . The synthetic diesel fuel of  claim 26 , wherein said fuel is formulated to burn with a substantially lower “dpm” content: in emission gases than in conventional diesel fuels.  
   
   
       28 . The synthetic diesel fuel of  claim 26 , wherein said fuel is a linear paraffin-linear olefin composition with a minor percentage of branch paraffins and branch olefins.  
   
   
       29 . The synthetic diesel fuel of  claim 28 , wherein said fuel has less than 5.0% of petroleum-based diesel fuel additive to enhance lubricity.  
   
   
       30 . A method for achieving optimum diesel engine performance and maximum removal of DPM and CO from diesel emission gases, comprising the steps of: 
 formulating a paraffinic-type synthetic diesel fuel characterized by having a high cetane number over 60 and a negligible amount of sulfur, aromatics and nitrogen content, and providing a supply thereof for the diesel engine; and    dispersing emission gases from the diesel engine through another emission processing device or directly to ambient.    
   
   
       31 . The method according to  claim 30 , including formulating the synthetic diesel fuel to have less than 1.0% of sulfur, aromatics and nitrogen respectively.  
   
   
       32 . The method according to  claim 30 , including formulating the synthetic diesel fuel to have a Cetane rating in the range of 60 to 80.  
   
   
       33 . (canceled)  
   
   
       34 . The method according to  claim 30 , in which the synthetic diesel fuel is formulated to effect a reduction in particulate matter (dpm) in discharged engine emission gases by 20% to 40%.  
   
   
       35 . The method according to  claim 40 , in which the chemical hydrocarbon cleaner of the water bath is formulated to remove up to 80% of the residual particulate matter (dpm) from discharged engine emission gases.  
   
   
       36 . The method according to  claim 30 , including the further step of pre-filtering the synthetic diesel fuel upstream of the diesel engine to remove non-combustibles therefrom.  
   
   
       37 . A diesel emissions control system for removing diesel particulate matter (“dpm”) from diesel engine exhaust comprising, in combination, a supply of linear paraffinic-type synthetic diesel fuel having a Cetane rating of over 60 for the diesel engine; a diesel fuel pre-filter constructed and arranged between the supply of synthetic diesel fuel and the diesel engine for filtering non-combustible contaminates from the synthetic diesel fuel to thereby provide it substantially totally-combustible fuel to the engine, and an aqueous filter apparatus in the emissions output from the diesel engine and being constructed and arranged to form a water bath through which all “dpm” laden exhaust gases must pass before discharge to ambient, the water bath of said aqueous filter apparatus having a major water constituent and a minor constituent amount of a super-wetting agent having a relatively high affinity for hydrocarbons.  
   
   
       38 . The emissions control system of  claim 37 , in which the synthetic diesel fuel is formulated to reduce particulate matter (dpm) in discharged engine exhaust gases by 20% to 40%.  
   
   
       39 . The emissions control system of  claim 38 , in which the super-wetting agent of the water bath is formulated to remove up to 80% of the particulate matter (dpm) from the residual engine emissions gases.  
   
   
       40 . The method of  claim 30 , in which said emission processing device is a water bath having water as a major constituent and, as a minor constituent, a wetting composition comprising a chemical hydrocarbon cleaner comprising at least one component selected from the group consisting of detergents, soaps, surfactants and mixtures thereof, and a defoaming agent.