Apparatus and method for emissions containment and reduction

The method of purifying segments of an exhaust gas stream from an engine containing harmful and non-harmful constituents comprising the steps of:

• blocking the exhaust passage downstream of the engine when a segment of the exhaust gas stream contains harmful constituents to thereby prevent emission of harmful constituents into the atmosphere,
• directing the segment of the exhaust gas stream containing harmful constituents to a conduit effective to retain the exhaust gas containing harmful constituents within the conduit upstream of a second gas occupying the conduit before the inflow of the exhaust gas containing harmful constituents, wherein the conduit has a substantially fixed volume,
• opening the exhaust passage and blocking flow of the exhaust gas into the conduit to thereby retain within the conduit the segment of the exhaust gas stream containing harmful constituents,
• and recycling the segment of the exhaust gas stream containing harmful constituents from the conduit, except condensed and settled out constituents, through the engine,
• whereby the segment of the exhaust gas stream containing harmful constituents are reduced.

The method of reducing exhaust of harmful gases from an engine comprising the steps of:

• passing the gases through an exhaust gas reaction device effective to cause reaction of harmful exhaust gas constituents when the temperature of said reaction device is above a minimum temperature,
• blocking said exhaust passage downstream of said reaction device when the temperature of said reaction device is below said minimum temperature to thereby prevent emission of unreacted exhaust gas constituents to the atmosphere,
• directing exhaust gases flowing unreacted from said reaction device when the temperature of said reaction device is below said minimum temperature to a conduit effective to retain said exhaust gas constituents within said conduit, except condensed and settled out constituents, substantially upstream of a second gas occupying said conduit before the inflow of said exhaust gas, wherein the conduit has a substantially fixed volume greater than 30 liters,
• opening the exhaust passage and blocking flow of the exhaust gas into said conduit to thereby contain within said conduit the segment of the exhaust gas stream containing harmful constituents,
• and recycling the exhaust gas from said conduit, except condensed and settled out constituents, through said reaction device when the temperature of said reaction device is above said minimum temperature,
• whereby exhaust gas constituents passed unreacted through said reaction device when the temperature of said reaction device is below said minimum temperature are recycled through and reacted in said reaction device when the temperature of said reaction device is above said minimum temperature.