Method for burning solid or semi-solid fuel

A zero-smog combustion technology of bitumite, lignite, biomass fuels, and waste plastics such as polyolefin,

• in comparison with a way of combusting a combustible solid substance such as bitumite, lignite and a plant fuel dispersedly and disorderly in existing medium-, small- and micro-sized stoves that leads to a massive amount of many kinds of pollutants such as smog in exhaust emission, the combustion technology is characterized by integrating 6 techniques, i.e., {circumflex over (1)} a gel paste or gel thin cake of low-carbon alcohols is used in combination with a straw charcoal grille as an oxidant-free and nontoxic ignition agent;
• {circumflex over (2)} in a formula of a fire-leading coal (10), a total volatile content is up to 30%-40%-50% to facilitate quick energizing after ignition and forming a continuous long-flame combustion;
• both of an ignition point and a particle size of each component of a combustible substance must be appropriately distributed to facilitate sequential and orderly combustion;
• after partially emulsified with KOH, a lignite humic acid and a carboxylic acid with a large molecular weight in other raw materials, together with a plant fuel alkalized by an alkaline substance such as KOH and Ca(OH)2, constitute a cheap organic binder to facilitate moderately reducing an ash content and increasing a calorific value and a mechanical strength;
• the raw material is not added with a toxic and harmful substance, there is less slag which is slightly loose to facilitate automatically falling, the slag contains a fertilizer element such as potassium, calcium, magnesium, silicon and sulfur and is slightly alkaline, and when used in combination with a grass fertilizer, it is suitable for improving a granular structure and fertility of an acid clay and may also be used as a cement additive;
• {circumflex over (3)} both of a top half part of a matched novel furnace core (2) and a novel fire-gathering plate (6) are modularly produced from a light-colored material that has both a dominated thermal insulation property and a fire resistant property, so as to facilitate forming a high-temperature zone in a large combustion chamber (7) soon after ignition, to facilitate horizontally stacking any number of composition units of coal briquettes in various kinds of hearths, and to facilitate promptly assembling the furnace cores in any shape and dimension on site when the hearth is reconstructed;
• {circumflex over (4)} the cross-sectional area of a primary air inlet of the stove and the vent holes of the coal briquette must be 10%-25%-30% larger than that of an anthracite originally burnt;
• the cross-sectional area of an inner ring vent hole (13) of the coal briquette is 30% or more larger than that of an outer ring vent hole (12) thereof to facilitate ensuring adequate oxygen supply necessary for complete combustion in the case of static combustion without an air blast, an industrial stove should be equipped with a programmed ventilation device to control a flame coming out from the hearth to be in a state of oxidizing flame all the time;
• {circumflex over (5)} inexpensive nanoscale Fe2O3 is added to a coal surface of the raw material as a catalyst of the coal gasification and water-gas shift reaction of the intramolecular and extramolecular moisture in a fixed carbon and the coal briquette in a micropore in a red hot layer and the vent hole in a red hot portion of the coal briquette which are two kind of self-contained coal gasification chambers that act as combustion chambers as well, so as to facilitate prolonging a long-flame combustion period substantially, and expensive ferrocene may not be used to catalyze the combustion of coal;
• and {circumflex over (6)} the composition unit of coal briquettes placed in the stove at one time is constituted by a coal placed underneath (9), the fire-leading coal (10), an ignition cake (9), a straw charcoal grille (11), and the ignition agent layer consisting of an ignition paste in this order from bottom to top, and any number of the composition units may be horizontally stacked;
• by means of igniting from the top of a coal briquette pile and combusting downward automatically, an orderly, long-flame, complete and zero-smog combustion throughout the whole process from the moment of the ignition of a solid fuel such as bitumite and lignite may be achieved, a sulfur-fixing rate is high, a heat-generating efficiency is high, a cleanliness of an exhaust gas discharged directly is close to that of natural gas, and the exhaust gas may be discharged directly.

The formulas and production processes exemplified in the specific embodiments are merely for further illustrating the content of the present disclosure, but are not limited thereto, and the embodiments are all included in the scope of the present disclosure as long as they adopt the following technical contents in the briquette fuels for “upper ignition-downward combustion”:

• 1. a gel paste or cake (8) of low-carbon alcohols is used as an ignition agent, and a straw charcoal and other plant charcoals are used as auxiliary ignition agents, regardless of how a formula, a production process and a packaging form are adjusted;
• 2. a formula and a molding process of a fire-leading coal (10), as long as a) an ingredient having a high volatile content of 30%-40%-50% is adopted, b) both of the ignition point and particle size of each fuel component are arranged in gradient to facilitate an orderly and sequential combustion, and c) after lignite and other materials containing a macromolecular organic acid are partially emulsified (neutralization reaction with potassium hydroxide and the like), the mixture and a plant fuel boiled with an alkaline substance such as potassium hydroxide, hydrated lime and plant ash together constitute a fuel and binder, so as to save the cost of the binder, regardless of how the formula, the production process and the packaging form are adjusted;
• 3. commercial iron sesquioxide containing at least 10% or more of iron sesquioxide and having a particle size of 50 nm or less is adopted to catalyze a part of a fixed carbon in a coal component to be gasified in a micropore and a vent hole in a red hot coal layer before combustion, so as to facilitate the extension of a long-flame combustion period;
• 4. a furnace core (2) has a height of at least from the bottom of the fire-leading coal (10) to the bottom of a fire-gathering plate (6), and the fire-gathering plate (6) itself is made from a light alkaline fire-resistant material having good thermal insulation property and containing a high content of magnesium and a low content of transition element(s);
• 5. a total area of an air inlet of a stove and the vent holes of the coal briquettes is enlarged by 10-20-30%, as compared to that of an anthracite originally used, and the diameter of an inner ring vent hole (13) is 10% to 11% larger than that of an outer ring vent hole (12);
• 6. after tests, a raw material does not contain radioactive elements beyond standard, does not contain lead, cadmium, arsenic, mercury, thallium, and beryllium, and does not contain halogen, much sulfur and nitrogen and other toxic and harmful substances, so the burnt slag mainly contains elements such as potassium, calcium, magnesium, iron, silicon and sulfur, thus being used as a fertilizer or a cement additive;
• and 7. various combustible solids and semi-solids, including a low-value waste thereof, may all be used as a formulated fuel according to the methods described in the present specification to realize highly efficient and clean combustion, and are thus included in the content of the present disclosure.