Processes for reducing shutdown time of a sub-system/ reactor component in an LDPE process. The process includes closing one or more pairs of upstream lock-out valves, each pair of upstream lock-out valves being located in an inlet stream upstream of the reactor component and configured to cease fluid flow into the reactor component through said inlet stream when said pair of upstream lock-out valves is closed; closing one or more pairs of downstream lock-out valves, each pair of downstream lock-out valves being located in an outlet stream downstream of the reactor component and configured to cease fluid flow out of the reactor component through said outlet stream when said pair of downstream lock-out valves is closed; depressurizing the reactor component; introducing purge gas comprising N.sub.2 into the reactor component at and withdrawing the purge gas from the reactor component.

The present disclosure belongs to the technical field of clean and efficient mining of deep unconventional or conventional resources, and discloses a pilot-scale supercritical water oxidation oil and hydrogen production system capable of realizing long-distance multi-stage heating of organic rock. The system comprises a supercritical water generator, a supercritical water pyrolysis reaction system for organic rock, an oxygen injection system and an oil-gas condensation and collection system, wherein the supercritical water generator mainly comprises a water injection system, a front-section preheating reaction system, a second-stage heating system and a third-stage heating system. The reaction system can carry out a pilot-scale simulation process of supercritical water pyrolysis for organic rock, a multi-stage heating function is realized, the maximum reaction distance is 8 m or more, and the release characteristics of oil-gas products under different reaction distances are explained. Meanwhile, the parameters of high-temperature residual carbon oxygenation hydrogen production are obtained, and the supercritical water oxidation oil and hydrogen production process of long-distance multi-stage heating of organic rock is completely simulated.

An autoclave system comprises an autoclave vessel 210, for performing a leaching operation on sacrificial ceramic cores (not shown) and a storage vessel 220 for containing caustic leaching fluid 230. Interposed in a fluid flow path between the vessel 210 and the tank 220 is a heat exchange unit 240, comprising a body 250 containing a thermal exchange medium, in the form of water 260, and first and second thermal exchange conduits represented at 270 and 280. A thermal exchange medium inlet pipe 290a and a thermal exchange medium outlet pipe 290b are provided to the body so that the medium 260 can be replenished, preferably substantially continuously, to optimize thermal transfer efficiency.

The invention relates to a pressure vessel, having: a reaction chamber (2) as a pressure space for the initiation and/or facilitation of chemical and/or physical pressure reactions of samples (P) accommodated in the reaction chamber (2); a fluid inlet (20) with a feed valve (21) which is adjustable between an open position, for the feed of a fluid, preferably a flushing gas, into the reaction chamber (2), and a closed position, for stopping the feed of the fluid; a fluid outlet (30) with a discharge valve (31), which is adjustable between an open position, for the discharge of a fluid out of the reaction chamber (2), and a closed position, for stopping the discharge of the fluid out of the reaction chamber (2); and an oxygen sensor (33) for detecting an oxygen content in the reaction chamber (2). The pressure vessel (1) furthermore has a control device which is configured to control the feed valve (21) and the discharge valve (31) on the basis of the oxygen content detected by the oxygen sensor (33), such that the reaction chamber (2) is flushed via the feed and discharge valves (21, 31) situated in the open position, and at least the discharge valve (31) switches from the open position into the closed position as soon as a predetermined oxygen content is undershot. The invention also relates to a corresponding method.

A vessel system for high-pressure reactions is disclosed. The system includes a plugged polymer cylinder reaction vessel with a pressure vent opening extending radially through the wall of the reaction vessel and a supporting frame into which the vessel is received. Complementing keying structure elements on the vessel and on the frame limit the orientation of the reaction vessel in the supporting frame and the radially extending vent opening to a defined single position.

The invention discloses a method for producing bio-fuel (BF) from a high-viscosity biomass using thermo-chemical conversion of the biomass in a production line (10) with pumping means (PM), heating means (HM) and cooling means (CM). The method has the steps of 1) operating the pumping means, the heating means and the cooling means so that the production line is under supercritical fluid conditions (SCF) to induce biomass conversion in a conversion zone (CZ) within the production line, and 2) operating the pumping means so that at least part of the production line is in an oscillatory flow (OF) mode. The invention is advantageous for providing an improved method for producing biofuel from a high-viscosity biomass. This is performed by an advantageous combination of two operating modes: supercritical fluid (SCF) conditions and oscillatory flow (OF).

In a method for the continuous precipitation of lignin from black liquor black liquor is provided so as to flow as a pressurized flow in a reactor with a dwell time of less than 300 s. An acidifying agent selected from the group of carbon dioxide, acid and their combinations is led to the flow at one or more feeding sites to lower the pH of black liquor. The pH is allowed to decrease by the effect of the acidifying agent in the pressurized flow to the precipitation point of lignin, the pressure of the pressurized flow is abruptly released, and lignin particles are separated from black liquor.

This specification discloses an operational continuous process to convert lignin as found in ligno-cellulosic biomass before or after converting at least some of the carbohydrates. The continuous process has been demonstrated to create a slurry comprised of lignin, raise the slurry comprised of lignin to ultra-high pressure, deoxygenate the lignin in a lignin conversion reactor over a catalyst which is not a fixed bed without producing char. The conversion products of the carbohydrates or lignin can be further processed into polyester intermediates for use in polyester preforms and bottles.

An instrument system for acid digestion is disclosed. The instrument includes a heating block, a reaction vessel formed of a polymer that is resistant to acid and other chemical attack at temperatures above 150° C. and that has a structure (thickness, etc.) sufficient to withstand pressures above atmospheric, a metal sleeve surrounding the polymeric reaction vessel, and an opening in the block that has a cross-section corresponding to the cross-section of the metal sleeve.

A reactor for performing a gas/liquid biphasic high-pressure reaction with a foaming medium, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone and a zone of limited backmixing, wherein the backmixed zone and the zone of limited backmixing are consecutively traversable by the reaction mixture, wherein the backmixed zone comprises means for introducing gas and liquid and a gas outlet and also comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the gas, and the zone of limited backmixing comprises a reaction product outlet, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a riser tube whose lower end is arranged within the backmixed zone and whose upper end opens into the zone of limited backmixing so that liquid from the backmixed zone can ascend into the zone of limited backmixing via the riser tube, wherein flow into the zone of limited backmixing enters from below. The reactor is configured such that the high-pressure reaction space is optimally utilized and contamination of workup steps or subsequent reactions arranged downstream of the high-pressure reaction with foam is substantially avoided. The invention further relates to a process for performing a continuous gas/liquid biphasic high-pressure reaction in the reactor.