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A new air injection technique, low temperature oxidation (LTO process), is described. Improved oil recovery from deep, light oil reservoirs is achieved by removing the ovgen in the injected air by spontaneous LTO reactions with the residual oil in the reservoir. The product of the LTO reactions is a 'yue gas", which displace the oil. Preliminary results of LTO reaction kinetics and oil recovery have been obtained using four North Sea light oils. The paper also contains some discussion of the safety issues related to air injection offshore.

A series of hot compression tests at the temperature of 700 °C were applied to study the effect of the ultrasonic surface rolling process (USRP) on the hot compression behavior of Inconel 718 superalloy. The results indicated that the USRP-treated samples exhibited a better ability to withstand axial hot compression than the untreated samples. After the hot compression process, the size of the matrix grains was slightly decreased, and the volume fraction of ultra-fine recrystallized grains in the near-surface regions was increased for the USRP-treated samples. In addition, for USRP-treated samples, a large number of γ″ phases with size less than 100 nm were precipitated within the broadened grain boundaries in the near-surface regions rather than the inner grains. The enhanced ability to withstand axial compression at 700 °C for USRP-treated samples was related to the ultra-fine microstructure induced by USRP, combined with the precipitation of nano-γ″ phases within broadened grain boundaries and the increase of ultra-fine recrystallized grains in the near-surface regions during the hot compression process.

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Ultrasonic surface rolling process (USRP) combined with deep cryogenic treatment (USRP+DCT) was applied on quenched and tempered Cr12MoV. The results indicated that USRP and USRP+DCT could significantly improve the surface mechanical properties, leading to smaller surface roughness and smoother morphology with less cracks and defects. Test of microhardness showed that the hardness increase of USRP and USRP+DCT were 16.4% and 23.6%, respectively. In addition, the wear resistance was improved by USRP and USRP+DCT. Compared with USRP, USRP+DCT can further improve the surface mechanical properties of Cr12MoV.