Method for preparing engine fuel gas by using biomass and/or organic waste

Abstract

The invention discloses a method for preparing an engine fuel gas by using biomass and / or organic waste and particularly relates to a method for producing high-heat value fuel gases for engines (or internal combustion engines) for vehicles and ships by performing primary medium-temperature thermal cracking of a raw material, performing secondary high-temperature thermal cracking and / or catalytic cracking, refining fuel gas, mixing the fuel gas and other steps and by a thermochemical conversion technique.

Description

technical field [0001] The invention relates to a method for producing engine gas by using biomass and / or organic waste as raw materials, and belongs to the field of petrochemistry; specifically, it belongs to a method of preparing raw materials and performing thermal cracking and / or catalytic cracking at different temperatures 1. Gas deacidification and refining, using thermochemical conversion technology to produce high calorific value vehicle engine (or internal combustion engine) gas. technical background [0002] With the rapid development of human social economy and the massive consumption of energy, the reserves of oil and natural gas in the earth's crust have been depleted day by day, forcing human beings to develop and utilize renewable resources on the earth's surface to compensate for their energy shortage. Using artificial synthesis methods, organic waste such as biomass and / or domestic garbage that can grow continuously on the surface of the earth's crust is use...

AI Technical Summary

Problems solved by technology

Gasification method is the process of using oxygen or oxygen-containing substances in the air as a gasification agent to oxidize carbon in biomass to generate combustible gas; however, the gas produced by this method contains about 45-57% (Wt%) Nitrogen (N 2 ) and 8-11% (Wt%) carbon dioxide (CO 2 ), they are inert gases that cannot burn and generate heat, resulting in a low calorific value of the gas produced, generally with a calorific value of 4500-5400KJ / m 3 (Standard state), as in CN1304976 "Method and gasification reaction device for preparing fuel gas by biomass gasification", the product combustible gas contains about 63% nitrogen, and the average calorific value is 1200 kcal / m 3 (standard state) or 4900KJ / m 3 (Standard status); On July 1, 2001, my country promulgated and implemented the national standard GB18047-2000 for compressed natural gas for vehicles. The high-level calorific value of gas stipulated in this standard must be greater than 31.4MJ / m 3 (or 31400KJ / m 3 , standard state), for carbon dioxide (CO 2 ), sulfur oxides (SO 2 ), hydrogen sulfide (H 2 S) and other acidic substances (such as NO 2 , HCl) have traces of strict control, and do not contain moisture; therefore, the gas produced by the gasification method has a low calorific value, complex components, and many impurities, which cannot meet the fuel requirements of the engine (or internal combustion engine), and cannot Used as engine fuel; usually, this low calorific value gas is mainly used as a heat source for power plants, as well as heating and gas supply for industrial or residential life; usually, the gas used by vehicle engines (or internal combustion engines) is mainly used It is natural gas and liquefied petroleum gas; natural gas is a multi-component mixed gas with methane as the main component. 3 (Standard state)

Biomass pyrolysis refers to the process in which biomass is thermally degraded or cracked under conditions of complete absence of oxygen or anoxic conditions, and finally produces bio-oil, charcoal and combustible gas; however, under normal conditions, bio-oil accounts for 40-60% ( Wt%), carbon and combustible gas account for 60-40% (Wt%), this bio-oil is a black mixture of complex organic components with extremely high oxygen content, including almost all kinds of oxygen-containing organic compounds, such as ether , esters, aldehydes, ketones, phenols, organic acids, alcohols, etc.; among them, the content of aromatic hydrocarbons such as benzene, anthracene, naphthalene, and phenanthrene and the content of some acids (such as wood acetic acid) are relatively large. The substance has strong corrosion and damage to the engine. The calorific value of bio-oil is about 17MJ / kg, which is only equivalent to 40% of the calorific value of gasoline or diesel oil of the same quality. It cannot be used as fuel for engines or internal combustion engine vehicles, usually only as low valuable burning oil

[0004] The combustible gas products obtained by existing biomass thermochemical conversion technologies (i.e., gasification and pyrolysis) contain a large amount of carbon monoxide (CO, with a calorific value of 12636KJ / m 3 , under standard conditions) and hydrogen (H 2 , 10798KJ / m 3 , under standard conditions), resulting in the calorific value of the collected combustible gas being far lower than the calorific value of the internal combustion engine gas (31400KJ / m 3 , standard state) standard requirements; in particular, the gas contains a certain amount of carbon dioxide (CO 2 ), sulfur oxides (SO 2 ), hydrogen sulfide (H 2 S) and other acidic substances (such as NO 2 , HCl) and other acid corrosive substances, which have serious damage to internal combustion engines or engines, and cannot be directly used as fuel for internal combustion engines or engines

[0005] There have been many reports on the comprehensive utilization of heat treatment technology for organic waste recycling; the organic waste referred to in the application of the present invention includes: household garbage and organic hydrocarbons; USP 5,744,668 and ZL98117823 authorized by the applicant of the present invention. 5 "Methods and Equipment for Producing Hydrocarbons from Household Garbage and / or Organic Waste" discloses a method of using domestic garbage and / or organic waste as raw materials to produce liquid hydrocarbon oil as the main product. A small amount of by-products obtained --- non-condensable flammable gas contains a certain amount of carbon dioxide (CO 2 ), sulfur oxides (SO 2 , SO 3 ), nitrides (NO, NO 2 ) and HCL and other acid gases, if this hydrocarbon combustible gas is used as fuel for internal combustion engines, it will cause serious corrosion of the engine;

[0006] In the ZL95195757.0 "method for producing gasoline, diesel and carbon black with waste rubber and / or waste plastic" authorized by the applicant of the present invention, ZL99107968. "method and equipment for producing gasoline and diesel with waste plastic and / or heavy oil", USP 6,270,630B1 and Patent No. 3043429 "Methods of Using Waste Rubber and / or Waste Plastics to Produce Gasoline, Diesel and Carbon Black", discloses the use of hydrocarbon organic waste (waste plastics, waste rubber, heavy oil) as raw materials to produce liquid hydrocarbon oil (gasoline and diesel oil) as the main product, there is no report on the technology and equipment for converting hydrocarbon oil into small molecule (methane, ethane, propane, ethylene, hydrogen) combustible gas; on November 11, 2003, the country promulgated and implemented GB19159-2003 national standard for liquefied petroleum gas for vehicles, which strictly controls trace amounts of sulfur content, total olefin content, butadiene content, copper sheet corrosion, distillation residue, hydrogen sulfide content, etc., and does not contain Moisture; therefore, the composition of gas produced by pyrolysis of hydrocarbon organic waste (such as waste rubber, PVC) is complex, and there are many impurities such as olefins, sulfur and acidic substances, which do not meet the national standard of GB18047-2000 compressed natural gas for vehicles Nor does it meet the specification requirements of GB19159-2003 liquefied petroleum gas for vehicles, so they cannot be directly used as engine fuel;

[0007] So far, in China and the world's patent literature database, related books, journals, magazines and industrial production applications, there is no report on the use of biomass and / or organic waste to produce high calorific value engine gas

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