a fuel cell system without a high pressure line of a hydrogen supplying system, including a gas charging line formed between a gas charging station and a high pressure vessel charged with gas by the gas charging station, and a gas supplying line formed between the high pressure vessel and a stack, includes: a regulator provided in the gas supplying line; a solenoid valve provided in the gas supplying line between the regulator and the high pressure vessel; and a check valve provided in a bypass line connecting one point of the gas supplying line between the regulator and the solenoid valve and one point of the gas charging line.

A corrosion inhibitor additive is circulated in a system with a corrosion environment to inhibit metal corrosion. The corrosion inhibitor additive includes a first component and a second component. The second component includes without limitation, imidazolines, amides, quaternary amines, carboxylic acid reaction products, organophosphates, phenathradine derivatives, heterocyclic molecules containing one or both of nitrogen and sulfur, and combinations thereof. The first component may have one of the following formulas:

##STR00001##

wherein x is oxygen or hydrogenated nitrogen or quaternized nitrogen; R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently hydrogen, methyl or an alkyl group; p, q and n are independently integers from 1 to 100; and

SHCH.sub.2[CH.sub.2OCH.sub.2].sub.zCH.sub.2SH(A1)

where z is an integer ranging from 1 to 100; and where a lower amount of the corrosion inhibitor additive is used to achieve the same or better results in inhibiting the corrosion of the metal surface as compared to an otherwise identical method for inhibiting corrosion absent the corrosion inhibitor additive.

A method of hydraulic fracturing is provided which uses metal silicides to generate significant pressure inside a wellbore. The method comprises injecting a fracturing fluid and an aqueous or reacting fluid into the wellbore to react with the fracturing fluid. The fracturing fluid comprises metal silicide, which may be uncoated or coated, and hydrocarbon fluid. The reacting fluid comprises water or a solvent. A method of removing buildup in pipelines such as subsea pipelines which uses metal silicides to generate heat and pressure inside the pipeline is also provided. The method comprises injecting an organic slug and an aqueous slug. The organic slug comprises metal silicide and hydrocarbon fluid. The aqueous slug comprises water. Alternatively, there is also provided a method for purifying flowback water produced from a hydraulic fracturing process comprising adding metal silicide to the flowback water produced from a hydraulic fracturing process.

A system for reducing pressure and extracting energy from natural gas pipelines or the cryogenics industry can include an electrolyzer that produces hydrogen, a heating device adapted to heat the natural gas in the pipeline, and a device adapted to extract energy from expansion of the natural gas. The extracted energy can be used to power the electrolyzer and/or heat the natural gas. The system can be used to extract energy from gas expansion.

In a process for the catalytic conversion of organic oxygenates to hydrocarbons, a feed comprising at least one organic oxygenate is contacted with a zeolite catalyst under conditions effective to produce a hydrocarbon product comprising aromatics, olefins and paraffins. At least a fraction of the hydrocarbon product containing C.sub.4+ hydrocarbons, including at least part of the olefins, is then contacted with hydrogen in the presence of a hydrogenation catalyst under conditions effective to saturate at least part of the olefins in the C.sub.4+-containing fraction and produce a hydrogenated effluent containing less than 1 wt % olefins. The hydrogenated effluent is useful as a diluent for heavy crude oils.

Biomass feedstocks (e.g., plant biomass, animal biomass, and municipal waste biomass) are processed to produce useful products, such as fuels. For example, systems are described that can convert feedstock materials to a sugar solution, which can then be fermented to produce ethanol.

An infrastructure monitoring assembly includes a nozzle cap, the nozzle cap comprising a metallic material; an antenna cover, the antenna cover attached to the nozzle cap, the antenna cover comprising a plastic material, the antenna cover defining an antenna cavity; and an antenna extending into the antenna cavity. An infrastructure monitoring assembly includes a fire hydrant, the fire hydrant defining a nozzle; a nozzle cap, the nozzle cap comprising a metallic material, the nozzle cap attached to the nozzle and sealing the nozzle; an antenna cover attached to the nozzle cap, the antenna cover comprising a plastic material, the antenna cover defining an antenna cavity; and an antenna disposed within the antenna cavity.

Provided is a gas pressure feed device including a compression device for compressing gas supplied from the upstream process and sending the gas to the downstream process, a shut off device provided in the downstream further than the compression device for shutting off the gas heading toward the downstream process, and a recirculation device for recirculate the gas shut off by the shut off device to the upstream of the compression device. The shut off device includes a first port on a primary side for introducing the gas from the compression device, a second port on a secondary side for sending the gas to the downstream process, a third port on the secondary side for sending the gas to the recirculation device, and a switching device for switching the gas heading toward the secondary side to either the second port or the third port.

Controlling flow of gas in a gas pipeline network, wherein flow of gas within each pipeline segment is associated with a direction (positive or negative). Minimum and maximum delivery rates to each gas receipt facility are determined. Lower and upper flow bounds of gas delivery rate are created by bounding minimum and maximum signed flow rates using minimum and maximum delivery rates, respectively, for each pipe segment. A pressure drop relationship for each pipeline segment within the lower and upper flow bounds is linearized to create a linear pressure drop model for each pipeline segment. A network flow solution is calculated, which includes flow rates for each pipeline segment and pressures for each network nodes to satisfy the lower and upper flow bounds on the gas delivery rate. The network flow solution is associated with control element setpoints used by a controller to control one or more control elements.

A system and method for controlling delivery of gas, including a gas pipeline network having at least one gas production plant, at least one gas receipt facility of a customer, a plurality of pipeline segments, and a plurality of control elements, one or more controllers, and one or more processors. The hydraulic feasibility of providing an increased flow rate of the gas to the gas receipt facility of the customer is determined using a linearized pressure drop model. A latent demand of the customer for the gas is estimated using a latent demand model. Based on the hydraulic feasibility and the latent demand, a new gas flow request rate from the customer is received. A network flow solution is calculated based on the new gas flow request rate. The network flow solution is associated with control element setpoints used by a controller to control one or more control elements.