A method of producing a coal blend by blending plural brands of coal to produce a coal blend includes letting a surface tension of coal when inert material is assumed to be 100 vol % be γ.sub.100, and letting a surface tension of coal when reactive material is assumed to be 100 vol % be γ.sub.0, determining γ.sub.0 of coal; among brands of coal 1, 2, . . . i, . . . , and n to be blended in a coal blend, specifying coal i in which γ.sub.100 is outside of γ.sub.0; measuring TI of coal i; and determining a blending ratio of coal i such that w calculated by formula (1) is 20.4 mass % or less

w=Σ(xi×TIi)  (1).

Methods are provided for accurately blending biodiesel into distillate streams to achieve a pre-determined percentage of biodiesel in the distillate, applicable to wild-type distillate streams as well as distillate streams that already contain some percentage of biodiesel.

Methods of controlling hydrogen sulfide concentration of a biogas occupying an anaerobic membrane bioreactor (AnMBR) containing a submerged membrane are disclosed herein. Methods of controlling dissolved sulfide concentration of a mixed liquor within the AnMBR are disclosed. The methods include directing wastewater containing sulfur and a chemical oxygen demand (COD) to an AnMBR, withdrawing at least a fraction of the biogas from the AnMBR, directing a pre-determined amount of the withdrawn biogas to a scrubber, directing a remainder of the withdrawn biogas to a gas distributor, and directing the scrubbed biogas to the AnMBR. Systems for treating wastewater having sulfur and COD are disclosed. The systems include an AnMBR, a scouring gas closed loop, a scrubber, and a control mechanism for directing biogas to the scrubber and to a gas distributor. Methods of retrofitting a system for treating wastewater having sulfur and COD are disclosed.

A process for the removal of hydrogen sulfide and sulfur recovery from a H.sub.2S-containing gas stream by catalytic direct oxidation and Claus reaction through two or more serially connected catalytic reactors, wherein a specific control of the oxygen supplement is operated. The control and improvement of the process is obtained by complementing, in each major step of the process, the H.sub.2S-containing gas stream by a suitable flow of oxygen, namely before the H.sub.2S-containing gas stream enters the Claus furnace, in the first reactor of the process and in the last reactor of the process. Especially in application in a SubDewPoint sulfur recovery process the H.sub.2S/SO.sub.2 ratio is kept constant also during switch-over of the reactors R1 and R by adding the last auxiliary oxygen containing gas directly upstream the last reactor R so that the H.sub.2S/SO.sub.2 ratio can follow the signal of the ADA within a few seconds.

Various illustrative embodiments of a system and process for recovering high-quality biomethane and carbon dioxide product streams from biogas sources and utilizing or sequestering the product streams are provided. The system and process synergistically yield a biomethane product which meets gas pipeline quality specifications and a carbon dioxide product of a quality and form that allows for its transport and sequestration or utilization and reduction in greenhouse gas emissions. The system and process result in improved access to gas pipelines for products, an improvement in the carbon intensity rating of the methane fuel, and improvements in generation of credits related to reductions in emissions of greenhouse gases.

A fuel synthesis device includes: a supplier to supply CO.sub.2 and H.sub.2 gasses; a fuel synthesis catalyst to chemically react the CO.sub.2 and H.sub.2 gasses to synthesize fuel; a gas-liquid separator to liquefy the fuel into liquid and separate the liquid from a gas containing unreacted CO.sub.2 and H.sub.2 gasses, and CH.sub.4 gas as a side product; a return path to return the separated gas to a point between the supplier and the fuel synthesis catalyst; a bypass path to bypass, and merge downstream of, the return path, and to include a CH.sub.4 separator to separate the CH.sub.4 and a CH.sub.4 oxidation catalyst to oxidize the CH.sub.4; and a switching valve to selectively switch between communication with the return path and communication with the bypass path, wherein whether the switching valve communicates with the return path or bypass path is controlled based on the density of CH.sub.4.

A multifunctional experimental system for in-situ simulation of a gas hydrate includes a computed tomography (CT) scanning device, a reactor, and a pipeline system. The reactor includes: a reactor upper end cover, a reactor lower end cover, a reactor housing and a clamp holder. A first pipeline channel is formed at a top, an upper groove is formed at a bottom, and a first upper joint is arranged in the upper groove. A second pipeline channel is formed at a side, a lower groove is formed at a top, and a first lower joint is arranged in the lower groove; where two ends of the reactor housing are respectively fixed to the reactor upper end cover and the reactor lower end cover. A top end of the clamp holder is provided with a second upper joint, a bottom end of the clamp holder is provided with a second lower joint.

The present disclosure provides a dehydration and upgrading system for a high-water-content material, including a reaction kettle, a steam generator and a steam recovery apparatus, wherein the steam generator and the steam recovery apparatus are located at left and right sides of the reaction kettle respectively, and are connected through steam pipelines; a pressure sensing device is arranged on the reaction kettle to sense the pressure therein; a feed port is formed at an upper end of the reaction kettle; a discharge port is formed at a lower end of the reaction kettle; a discharge conveying belt is arranged below the discharge port; a high-pressure air pipe is arranged on one side of the middle part of the reaction kettle; and a high-pressure air valve is arranged on the high-pressure air pipe.

A volume of natural gas including a volume of methane and a volume of other alkanes may be cleaned of the other alkanes using a steam reformer system to create synthesis gas.

A system for torrefaction of waste material comprising biogenic material and plastic material may comprise a material pre-processing system, a heating and compaction unit, a reactor system comprising a reaction portion and an extrusion portion, and a cutting unit adjacent an outlet of the reactor system. A method for operating a system for torrefaction of waste material comprising biogenic and plastic material may comprise processing the waste material to generate waste material having an aspect ratio between 0.8:1 and 1.2:1 and a largest dimension of less than 4 millimeters (mm); compressing and heating the pre-processed waste material in the heating and compaction unit; heating the compacted waste material in the reactor system to a temperature of 280° C.-500° C.; extruding material from the reactor system; and cutting the extruded material into pellets.