Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects soot/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide, has a carbon content of 0.05 wt % or more, and has a defect site in which oxygen deficiency occurs in a crystal structure.

The reduction of the acid gas concentration in the flue gas of combustion units that is produced in waste incinerators, by contacting the flue gas with a powder composition including an alkaline earth metal salt and an ammonium salt. The contact may be carried out in a combustion furnace and/or in a post-combustion chamber of the combustion units.

In a high-efficient clean, high-variable load rate coal-fired power generation system, through the internal thermal source SCR denitration catalytic module coupled with high temperature and low temperature storage tanks, the operating temperature of the internal thermal source SCR denitration catalytic module is controlled in a range of 300° C. to 400° C., ensuring that the SCR catalyst has high activity in full-working conditions. Moreover, the high temperature and low temperature storage tanks are coupled with the high-pressure heater group for steam turbine regenerative system, so that when the coal-fired unit needs to increase load rate, the thermal storage energy is quickly converted into output power. In addition, energy stored in the high temperature and low temperature storage tanks come from both the internal thermal source SCR denitration catalytic module and the thermal storage medium heater within the boiler, the operational flexibility and the boiler efficiency are improved.

Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects ash dust/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide including vanadium pentoxide and has a defect site in which an oxygen atom is deficient in a crystal structure of the vanadium pentoxide.

A burner characterized by being equipped with: a fuel supply nozzle to which a mixed flow of a solid fuel and a solid fuel transport gas is supplied; a flow passage that is arranged on the outside of the fuel supply nozzle and that supplies combustion air separated from the mixed flow; and ammonia supply nozzles which are capable of supplying ammonia on the downstream side of the outlet of the fuel supply nozzle toward a reduction region in which oxygen in the transport gas has been consumed due to ignition of the fuel and the progress of combustion, resulting in a low oxygen concentration. Thus, it is possible to provide a burner capable of burning a mixture of a solid fuel and ammonia, and a combustion device equipped with this burner.

Some non-limiting embodiments of the present disclosure relate to a method of regenerating at least one filter medium, the method comprising flowing a flue gas stream through or by the at least one filter medium at a first temperature and increasing the temperature of the flue gas stream from the first temperature to a second temperature that exceeds the first temperature. Some non-limiting embodiments of the present disclosure relate to a method of cleaning a flue gas stream, the method comprising maintaining the NO.sub.x removal efficiency by increasing the temperature of the flue gas stream from the first temperature to a second temperature that exceeds the first temperature.

Provided is a combustion device including: a burner that includes an ammonia injection nozzle having an injection port that faces an inner space of a furnace; and an adjustment structure that adjusts a separation distance between the injection port and the inner space.

Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent. This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects ash dust/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide including vanadium pentoxide and has a defect site in which an oxygen atom is deficient in a crystal structure of the vanadium pentoxide.

A flue pipe filter device for reducing nitrogen oxide (NOx) emission levels from gas fired appliances may include a flue cap with a pipe connection adapter sized to attach to an existing exhaust pipe; a fanned flue cap body with vents operatively attached to a distal end of the pipe connection adapter; and a filter positioned within the fanned flue cap body, the filter designed to convert NOx emissions into reduced NOx emissions. The filter may have an interior honeycomb structure.

An improved method and system for treating flue gases from a natural gas furnace are provided. The method and system include an acidic gas trap (AGT) adsorber which enables the continuous adsorption and storage of SOx, NOx redox, and formic acid/CO/HC/CH.sub.4 oxidation, with a negligible pressure drop. The AGT adsorber includes a catalyst coating having a nanotube structure (e.g., a uniform nanostructure forest coating) or a uniform porous nanostructure of various low-cost oxides through scalable low temperature solution processes, including oxides of Ti, Cu, Ba, Mn, Zr, Zn, Sr, Ca, Li, K, Na, Al, or Ce.