Method for preparing biodiesel

Abstract

The invention discloses a producing method for biodiesel fuel, which comprises the following steps: a filtering step, namely using waste grease of animals or plants as base oil, and after filtering preliminarily and heating the waste grease to a flowing state, removing filter residue of the base oil through a screen mesh; a dehydrating step, namely dehydrating the base oil of which the filter residue is removed in vacuum under the condition of heating at high negative pressure; an etherifying step, namely adding methanol, sulphuric acid and catalysts into the dehydrated base oil to carry out esterification reaction at least twice under the condition of heating; a methanol recycling step, namely reclaiming the methanol from the base oil after the esterification reaction through a condenser under a low negative pressure environment at a temperature of between 85 and 90 DEG C; and a step of separating the biodiesel fuel, namely separating the biodiesel fuel in the base oil after the methanol is reclaimed. The producing method has the advantages of full esterification, simple operation, low production equipment cost, and quick product yielding speed; and the production method can meet production requirements at normal temperature and normal pressure.

Description

technical field [0001] The invention relates to a method for producing biodiesel, in particular to a method for producing biodiesel using waste oil from animals and plants such as waste oil and hog oil as raw materials. Background technique [0002] Biodiesel is a typical green energy, especially the production of biodiesel from animal and plant waste oils such as waste oil and hog oil, which turns waste into treasure and prevents it from returning to the dining table to endanger human health. It is a technical hotspot widely concerned by all walks of life, and there are many production processes proposed for this technology. Each of these production processes has its own advantages and disadvantages. Difficulty in production operations. Although some processes have a sound theoretical basis, they require high equipment and require a large investment in actual operation, and even cannot be realized in actual production. Industrial production. Contents of the invention ...

AI Technical Summary

Problems solved by technology

[0002] Biodiesel is a typical green energy, especially the production of biodiesel from animal and plant waste oils such as waste oil and hog oil, which turns waste into treasure and prevents it from returning to the dining table to endanger human health. It is a technical hotspot widely concerned by all walks of life, and there are many production processes proposed for this technology. Each of these production processes has its own advantages and disadvantages. Difficulty of production operation

Although some processes have a sound theoretical basis, they require high equipment and require a large investment in actual operation, and even cannot be realized in actual production. Industrial production

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