A system and process for producing biofuel from spent coffee grounds (SCGs) comprises the steps of performing a first operation comprising the steps of obtaining spent SCGs from a source, washing the SCGs, mixing the washed SCGs with an inorganic acid and heating and stirring the washed SCGs to form a SCG slurry without separating coffee oil, drying the SCG slurry, mixing the dried slurry with a solvent and heating the dried slurry and solvent mixture to create a reaction to produce biofuel and residual grounds, and separating the biofuel from the solvent and the residual grounds. The process further includes the step of using an activation agent and heating the residual grounds and the activation agent to create activated residual grounds. Biochar is also produced without activation and heating de-oiled SCGs at lower temperatures without oxygen.

A method and system reprocess soiled animal bedding material commingled with animal manure. In one aspect the soiled animal bedding material is separated in a shaker to send at least a preponderance of said manure to a holding tank. In another aspect the bedding is cleaned, rinsed and color is restored. Said bedding material is subsequently dried and a bedding product, fertilizer product, and/or compacted product is formed. Alternatively, said bedding material is dried (without a compacting step) to form a product. In another aspect, the steps of separation, cleaning, rinsing and/or color restoration may be omitted.

Disclosed herein are scavenging and antifouling compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compositions as scavengers and antifoulants, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.

The present invention relates to a hydrogen sulphide scavenging additive composition for scavenging hydrogen sulphide including sulfur containing compounds and mercaptans, particularly for scavenging hydrogen sulfide in hydrocarbons, wherein the additive composition comprises substantially reduced amount of nitrogen based hydrogen sulfide scavengers, and is also required in substantially reduced amount, and wherein the additive composition scavenges the sulfur containing compounds not only at room temperature, but also at higher temperatures, and comprises at least a combination of: (A) at least one nitrogen based hydrogen sulfide scavenger; and (B) at least one aliphatic tertiary amine, wherein the nitrogen based hydrogen sulfide scavenger comprises triazine based hydrogen sulfide scavenger. In one embodiment, it also relates to a method for scavenging hydrogen sulfide in hydrocarbons, and in another embodiment it relates to a method of using an additive composition of the present invention for scavenging hydrogen sulfide in hydrocarbons. In yet another embodiment, it relates to a composition comprising (i) a hydrocarbon and (ii) a hydrogen sulfide scavenging additive composition for scavenging hydrogen sulfide in hydrocarbons.

The invention relates to a method for reducing the content of monoglycerides (MG), in particular saturated monoglycerides (GMG), in a raw biodiesel (RB), which has a content of monoglycerides (MG) of between 0.4 and 0.7 wt % and a content of free fatty acids (FFA) of less than or equal to 0.25 wt %, comprising the following steps: A) providing the raw biodiesel (RB) having the constituents indicated above in the concentrations indicated above; B) adding (1) an alkaline aqueous solution (L) to the raw biodiesel (RB); C) mixing the alkaline aqueous solution (L), and thus glycerides in the biodiesel, preferably monoglycerides (MG), in particular saturated monoglycerides (GMG), being hydrolyzed; D) performing a first centrifugal separation (2) of a heavy phase (6) comprising the alkaline aqueous solution (L) with the hydrolyzed constituents from a light phase (7) comprising the biodiesel; E) drying (5) the light phase (7) or (9) in order to provide a processed biodiesel for use as a fuel having a content of monoglycerides of less than 0.4 wt %. The invention further relates to a use according to the invention.

A method for removing heavy hydrocarbons from a feed gas by: feeding, into an absorber, a top reflux stream and a second reflux stream below the top reflux stream, wherein the absorber produces an absorber bottom product stream and an absorber overhead product stream; depressurizing and feeding the absorber bottom product stream to a stripper to produce a stripper bottom product stream and a stripper overhead product stream; cooling and feeding a portion of the absorber overhead product stream back to the absorber as the top reflux stream; and pressurizing and feeding the stripper overhead stream back to the absorber as the second reflux stream. A system for carrying out the method is also provided.

The invention relates to a process for recovering methane from digester biogas or landfill gas. More specifically, the invention pertains to a method for producing biomethane that removes impurities from a compressed digester biogas with staged membrane modules of at least two different types, to produce a biomethane having at least 94% CH.sub.4, below 3% of CO.sub.2, and below 4 ppm of H.sub.2S.

Oxygen is removed from a gas feed such as a landfill gas, a digester gas or an industrial CO.sub.2 off-gas by removing sulfur-containing compounds and siloxanes from the feed gas, heating the feed gas, injecting one or more reactants for oxygen conversion into the heated feed gas, carrying out a selective catalytic oxygen conversion in at least onesuitable reactor and cleaning the resulting oxygen-depleted gas. The reactants to be injected comprise one or more of H.sub.2, CO, ammonia, urea, methanol, ethanol and dimethylether (DME).

Embodiments described herein provide methods of operating a linear contactor for absorbing contaminants from a gas stream. The gas stream flows from a first end to a second end of the linear contactor. Fresh absorbent is provided at the first end of the linear contactor based on the theoretical minimum amount of absorbent needed to remove the contaminants. Absorbent is recycled from the second end to the first end of the linear contactor. Fresh absorbent is provided at the second end based on chemical condition of the recycled absorbent. Apparatus for practicing the method is also described.

The disclosure provides compositions and methods that are useful in removing, lowering, or otherwise controlling hydrogen sulfide and mercaptans. The compositions and methods can be used in any industry where hydrogen sulfide poses problems, such as when dealing with crude oil based, natural gas based, and/or coal based products. In some embodiments, the compositions include one or more alkoxylated amino formaldehyde adducts.