SE457355B - MAKE SURE TO PREPARE A CLEAN, CARBON OXIDE AND GAS GAS INCLUDING GAS - Google Patents

Description

1D 15 20 25 30 457 355 * The main object of the present invention is thus to "provide a method which allows the use of any carbon and / or hydrocarbon-containing starting materials for gas generation using commercially known technology, whereby the gas does not have to be subjected to energy-intensive and costly purification steps for use such as reduction gas, combustion gas or synthesis gas.

The main object is achieved in the manner initially indicated by the feature that the gas produced for the removal of hydrocarbons present in the gas is fed into a post-reaction chamber while simultaneously supplying a plasma gene. rator heated gas.

It has been found that by supplying a hot, plasma generator heated gas, which has a very high energy density, a thermal decomposition of hydrocarbons coming from the carburettor is obtained and the reaction with H 2 O, O 2 and / or CO 2 in the gas to form H2 and CO. Due to the high energy density in the supplied gas, a relatively small supplied gas volume is required, which makes the process possible.

The gas can be produced by pyrolysis or partial combustion of carbon and / or hydrocarbonaceous materials, such as peat, coal, anthracite, forest waste. In the event that coke oven gas derived from pyrolysis of coal is to be utilized, pollutants other than hydrocarbons are also included in the flight from the coal.

A major advantage of the invention is that these are also cleaved in the post-reaction chamber.

According to one embodiment, the gas is passed after the post-reaction chamber through a filling of limestone or dolomite for sulfur purification. The limestone and / or dolomite used for said sulfur purification also catalyzes the decomposition of hydrocarbons and the reaction with oxidizing agents. In this way, the electricity consumption in the post-reaction chamber stage can be reduced to a corresponding degree.

According to a further embodiment, the content of CO 2 + H 2 O in the gas from the post-reaction chamber is regulated to below 5%.

Further advantages and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawing, in which the figure schematically shows a flow chart of a gas production process according to the present invention connected to a subsequent reduction process.

A crude gas is produced in the name of a gasifier or coke oven. The generated crude gas is fed into a post-reaction chamber 2. At least one plasma generator 3 is arranged in connection with the post-reaction chamber 3 for supplying a hot gas with a high energy density. In the post-reaction chamber, hydrocarbons present in the crude gas are split and reacted to CO + H2. To adjust the hydrogen / carbon ratio, finely divided coke and H 2 O can be introduced through lances 4 into the post-reaction chamber.

Thereafter, the gas is subjected to a sulfur purification in the shaft 5 containing a filling 6 of limestone or dolomite, which is filled through a gas-tight lock device 7 while the spent filling is withdrawn at the bottom of the shaft through a gas-tight lock device 8. In addition, a catalytic decomposition of any remaining hydrocarbons in the gas. This can be used to reduce the electricity consumption in the plasma generator 3, which is used for thermal decomposition of the hydrocarbon content. The thus purified, essentially only H2 + CO and a small proportion of H2O + (Ib containing the gas) can then be transported further to a chamber 9 for regulating temperature and composition before entering the shaft furnace 10 for reduction of oxidic material.

The gas produced is fed through an inlet 12 located in the lower part of the shaft furnace 10 and is caused to flow in countercurrent to the metal oxide-containing material. The partially spent gas, contaminated with dust and dust, is drawn off through an outlet 13 and purified in a wash 14.

The purified, partially consumed gas can then be used for other purposes, as indicated by the arrow 15. A partial stream of the gas can, if necessary, be recirculated in the process, via the line 16, 16a, 16b, for example to be used in the mixing chamber 9 to regulate the temperature. and the composition of the gas which is then introduced into the shaft, and further a partial stream of the recycled gas can be used as gas in the plasma generator in the post-reaction chamber.

The invention is further elucidated below in connection with an exemplary embodiment. w EXAMPLE 10 tonnes of forest waste containing 30% water and with the element analysis. C H 0 N S Ash 51 6.2 42 0.2 0.5 0.5% is introduced into the top of a countercurrent carburettor per hour while oxidizing agent is introduced into the bottom of the carburettor in the form of air preheated to 1000 ° C. The air addition is about 10 15 457 355 3700 Nm3. The composition of the top gas is CO C02 H2 2 2 25.8 9.8 41.1 4.8 15.8 2.9% At the same time, a tar sample is taken, which shows that the gas contains 3.2 grams of tar / Nm3.

The temperature of the outgoing gas is SSOOC and its volume is about 17200 Nm3. The gas is now introduced into the post-reaction chamber and heated with plasma generator heated air. The required air volume is only about 2100 Nm3. With the help of the plasma generator, the temperature of the incoming gas is increased to 1250 ° C, whereby approximately 8.7 MWh of electrical energy is required.

The pyrolysis gas thus heated is thus freed from its methane and tar content, whereby the outgoing gas has the following composition CO CO 2 28.6 4, a, 29.6 13.6 23.1: The outgoing gas amount becomes about 19900 Nm 3.

Claims (1)

A 457 355 patent method for the production of a carbon monoxide and hydrogen gas containing gas which allows the use of commercially known technology and the use of any carbonaceous and / or hydrocarbonaceous feedstock, in which the gas does not need to be subjected to energy-intensive and costly purification steps. for use as a reduction gas, combustion gas or synthesis gas, characterized in that the gas produced to remove hydrocarbons present in the gas is fed into a reaction chamber in a simultaneous supply of a plasma generator-heated gas.