TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Device: The housing is in a self-contained shipping container. The housing has at least some ventilation openings but is fully sealable from the required environment, where ventilation driven by natural air flows is used by providing openings in a base wall or a lower portion of sidewalls in order to allow the escape of heavier than air gases and lateral openings and events in an upper region in order to allow the escape of lighter than air gases. The components of the plant located within the housing are as follows: a power generation unit is mounted at one end portion of the container; an oil expeller is mounted below the power generation; a raw material hopper is located on one lateral side of the container and communicating with the oil expeller; a mulch exhausts on the opposite lateral side of the container to the raw material hopper; a raw oil catch tray is located below the oil expeller; a raw oil holding tank in fluid communication with the raw oil catch tray; a finished biodiesel holding tank is located at a lower portion of the end of the container opposite to the power generation unit; and a compartment located towards the middle of the container, between the power generation unit and the finished biodiesel holding tank holding the chemical process equipment used to finish the biodiesel. The container is divided into at least two compartments, the larger is approximately double the size of the smaller, and delineating a hazardous area and separating it from a hot area. The container is spaced above the mount surface to promote natural flow under the container and circulation within the container. The container is provided with lifting/securing/transport points accessible only from within the container. The plant includes an oil expeller to pulp the raw feedstock and to produce the raw oil through physical liberation of the raw oil; includes a mixer to mix a catalyst with the raw oil where the raw oil is in a receptive condition through heating or disturbance, where the mixer has integrated heating provided to maintain the heat of the mixture whilst in the mixer; and includes at least a glycerin separation step and a methanol separation step, where the glycerin separation step includes the removal of methyl ester and the discharge of glycerin from the product mixture. The methanol separation takes place in a mechanical device that allows the methanol to flash vaporizes from the product mixture by using differential pressure rather than heat. The methyl ester undergoes filtration to provide an ultimate filtration size of approximately 1 micron and polishing to adsorb any remaining contaminants. The pH adjustment system is provided to ensure that the product biodiesel has a pH of approximately 7. The power generation unit produces an excess of power over that used by the plant. In biodiesel manufacturing plant, the power generation unit is fully enclosed within a separate compartment in the housing, where any waste heat from the power generation is used to provide heat to other process equipment or streams. Preferred Method: The raw oil from the oil expeller is pumped into a first heater and then to mixer where the catalyst is mixed and passes through a second heater, to a settling column allowing the methanol vapor from the top and from the bottom of the settling tank, then glycerin is drawn off, the main process material which is not in the bottoms or tops is then pumped through further separation steps, and at least one of which discharges to a methanol collector, through a pH adjustment step into a finished biodiesel holding tank. Alcoholysis or transesterification process is carried out in biodiesel plant.