Abstract: The system is provided for generating a mixed methane gas feed stream using at least one source of biogas and an alternate source of methane gas. The system includes a biogas subsystem, a control device for the methane gas from the at least one alternate source of methane gas, and a vertically-extending gas mixing vessel. A method of controlling a methane gas mass flow rate of a mixed methane gas feed stream is also disclosed. The proposed concept is particularly well adapted for situations where an uninterrupted and relatively constant input of methane gas is required to ensure an optimum operation of, for instance, a LMG production plant.

Abstract: The method is carried out for continuously producing a liquefied methane gas (LMG) from a pressurized mixed methane gas feed stream. It is particularly well adapted for use in relatively small LMG distributed production plant, for instance those ranging from 400 to 15,000 MT per year, and/or when the mixed methane gas feed stream has a wide range of nitrogen-content proportions, including nitrogen being substantially absent. The proposed concept can also be very useful in the design of medium-scale and/or large-size plants, including ones where the nitrogen content always remains above a certain threshold. The methods and arrangements proposed herein can mitigate losses of methane gas when venting nitrogen, for instance in the atmosphere.

Abstract: The gas flare system includes a vertical flare stack having an opened top end and a bottom floor wall. A weatherproof protective hood arrangement prevents rain and snow from entering through the opened top end. The gas flare system also includes a burner arrangement provided through the bottom floor wall. The burner arrangement receives a waste gas stream from a waste gas circuit and also primary air. Secondary air orifices around the burner supply secondary air coming from a plenum housing located directly underneath the bottom floor wall. The gas flare system can destroy the flammable gas in the waste gas stream with a combustion efficiency of more than 99% under almost any operating conditions. It can start automatically and operate efficiently without any supervision under any possible atmospheric conditions. A method of destroying a flammable gas in a waste gas stream is also disclosed.

Abstract: The system is provided for continuously separating landfill gas in a raw multi-phase stream coming from a landfill gas collector. The system includes an atmospheric tank and an elongated separator vessel mounted substantially upright above the tank bottom. The elongated separator vessel includes a mid-level inlet that is configured and disposed to be in fluid communication with the landfill gas collector pipe, an upper gas outlet located vertically above the mid-level inlet, and a bottom-opened discharge end that is located vertically below the mid-level inlet. A method of pretreating a raw multi-phase stream captured from a landfill site is also disclosed. The proposed concept provides a relatively simple arrangement that can be made sufficiently rugged to perform a pretreatment of the raw multi-phase stream in a continuous manner and with a very minimal intervention from landfill operators under almost any weather and operating conditions.

Abstract: The gas flare system includes a vertical flare stack having an opened top end and a bottom floor wall. A weatherproof protective hood arrangement prevents rain and snow from entering through the opened top end. The gas flare system also includes a burner arrangement provided through the bottom floor wall. The burner arrangement receives a waste gas stream from a waste gas circuit and also primary air. Secondary air orifices around the burner supply secondary air coming from a plenum housing located directly underneath the bottom floor wall. The gas flare system can destroy the flammable gas in the waste gas stream with a combustion efficiency of more than 99% under almost any operating conditions. It can start automatically and operate efficiently without any supervision under any possible atmospheric conditions. A method of destroying a flammable gas in a waste gas stream is also disclosed.