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A vehicular adsorbed natural gas (ANG) tank system operates as a mobile, dual gas storage/separation system to enable off-the-natural-gas-grid producers of biogas to use, ship, and process biogas for: (a) onboard delivery to engine of on-demand delivery of methane-rich fuel to an internal-combustion engine; (b) onboard separation of methane from carbon dioxide and extraction of unused fuel as carbon-dioxide-rich commodity, and (c) and large-scale, tractor-trailer shipping of biogas to a biogas upgrading plant and separation of methane from carbon dioxide during discharge at the plant. A mobile tank system on a vehicle comprises vessels filled with porous adsorbent and pressure valves; pressure regulators; pressure/temperature transducers at inlet, outlet, intermediate ports; and an onboard compressor/gas extraction pump. The tank discharging procedure for the separation of biogas into methane and carbon dioxide is such that the concentration of methane in discharged gas is at least 10% greater than in biogas.
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A Chemical Pump that Generates High‐Pressure Gas by Transmitting Liquid Fuel against Pressure Gradient
A pneumatic soft robot can be made autonomous by carrying a liquid chemical fuel. In the existing design, to transmit the fuel, the pressure of the fuel tank must exceed that of the actuator. Consequently, the fuel tank must be sufficiently stiff, which hardens the robot. Herein, inspired by pit membranes in trees, a chemical pump is developed, which is consisting of a nanoporous membrane between the fuel tank and the actuator, and coated with a catalyst on the side of the actuator. The fuel in the fuel tank migrates across the membrane and, on meeting the catalyst, decomposes into a pressurized gas and inflates the actuator. The chemical pump is driven by the free energy of reaction, against the difference in pressure. The pores in the membrane are large enough for the fuel molecules to migrate through, but small enough to block the pressurized gas to tunnel back. In a demonstration, the fuel tank has ambient pressure, and the actuator has a pressure of 350 kPa, comparable to the pressure in a car tire. The chemical pump enables pneumatic robots to be autonomous, powerful, and soft.
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- Award ID(s):
- 2011754
- PAR ID:
- 10500408
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 4
- Issue:
- 5
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/aisy.202100246
