Background: Thermal pretreatment of biomass ranges from simple (nondestructive) drying to more severe treatments that cause devolatization, depolymerization and carbonization. These pretreatments have demonstrated promise for transforming raw biomass into feedstock material that has improved milling, handling, storage and conversion properties. In this work, southern pine material was pretreated at 120, 180, 230 and 270°C, and then subjected to pyrolysis tests in a continuous-feed bubbling-fluid bed pyrolysis system. Results: High pretreatment temperatures were associated with lower specific grinding energies, higher grinding rates and lower hydrogen and oxygen contents. Higher pretreatment temperatures were also correlated with increased char production, decreased total acid number and slight decrease in the oxygen content of the pyrolysis liquid fraction. Conclusion: Thermal pretreatment has both beneficial and detrimental impacts on fast pyrolysis conversion of pine material to bio-oil, and the effect of thermal pretreatment on upgrading of pyrolysis bio-oil requires further attention.

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Achieving flow performance in openhole sand control completions often requires removal of the annular gap between the screen section and wellbore. For the first time in the industry, patented hydraulic screen technology has been used to provide wellbore support and overcome the challenges associated with gravel packing in depleted reservoirs with low operational margins. This paper demonstrates how new technology has been adopted by an operator in Norway to provide effective downhole sand control in an offshore environment faced with continuous reservoir pressure depletion. Detailed job planning and evaluation of risks when adopting new technology is described.The case study describes a producer well drilled to 2580 m, at a maximum deviation of 30º, and temperature approximately 90ºC. With the sand control equipment run to depth closed ended, the liner hanger and hydraulic screens are set by surface applied pressure. When set, the screens extend radially to close the annular gap and provide wellbore support; production ports in each screen provide the flow path from the reservoir to production tubing. The liner hanger packer was set and reservoir isolation barrier valve closed in the same trip providing testable barriers, prior to displacing the well for upper completion operations.The paper outlines how adopting new technology challenges openhole gravel packing and delivers effective downhole sand control in a depleted reservoir. The operator has demonstrated savings associated to operational planning, logistics, HSE risks and rig time. Production rates meet expectations with all screens contributing to flow.

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