| abstract |
Product yield and quality is increased during in situ retorting of oil shale by pulsed combustion in which the flow of feed gas to the flame front is intermittently stopped while continuously retorting the oil shale. In the process, a water purge is injected into the retort between pulses of feed gas to enhance transfer of sensible heat from the combustion zone to the retorting zone and enlarge the separation between the combustion zone and the advancing front of the retorting zone. Retort water produced during retorting can be used as part of the water purge and/or feed gas for process economy and efficiency. |