A method of reducing sulfur dioxide emissions of a circulating fluidized bed boiler plant. A first stream of sulfur-containing carbonaceous fuel is fed at a first feeding rate to a furnace of the boiler. A second stream of calcium carbonate containing absorbent having a predetermined d50 particle size is fed at a second feeding rate to the furnace. Oxygen containing gas is fed to the furnace for fluidizing a bed of particles forming in the furnace. Fuel is combusted with the oxygen and the sulfur in the fuel is oxidized to sulfur dioxide. The calcium carbonate is calcined to calcium oxide in the furnace. A portion of the calcium oxide is used to sulfate a first portion of the sulfur dioxide to calcium sulfate in the furnace.

A method and apparatus are provided for treating exhaust from a solid fuel combustion system such as a furnace or boiler and includes combusting a material in the combustion chamber and separating fly ash and char from a flue gas stream. The separated fly ash and char mixture is then separated further by separating smaller ash particles from larger char particles. The larger char particles are then reduced in size by a reducing device such as a grinder or crusher. Char particles that have been reduced in size by the grinder or crusher are then reinjected into the combustion chamber for re-burning.

A method for removing noxious, hazardous, toxic, mutagenic, and/or carcinogenic compounds and/or precursor compounds from a comingled gas, liquid, and/or solid stream is described. In one embodiment, the method is used to prepare the stream for feeding to an oxidizer, such as a thermal oxidizer, to reduce the amount of particulate matter discharged by the oxidizer and includes passing the stream through an ambient or chilled temperature condenser followed by an optional gas/solid separator, and one or more gas scrubbers prior to feeding to the oxidizer.

A circular fluidizing bed combustion system with uniform airflow distributing device is provided. The system comprises a fluidizing bed and a uniform airflow distributing device. The fluidizing bed is comprised of a fluidizing bed boiler body, an airflow distributing plate and a plurality of air caps, wherein, the airflow distributing plate is provided inside the fluidizing bed boiler body and divides the inner space of the fluidizing bed boiler body into a fluidizing chamber which is located in the upper portion of the boiler body and an air chamber which is located in the lower portion of the boiler body, and the plurality of air caps are arranged on the airflow distributing plate for injecting the fluidizing air into the fluidizing chamber. The inner space of the air chamber is divided into a distributing chamber that is located under the airflow distributing plate and an air inlet chamber that is located on one side of the distributing chamber by means of a perforated plate. The distributing chamber is comprised of a front wall, two side walls, a top wall that extends upwards obliquely from the upside of the front wall, and a bottom wall extends downwards obliquely from the downside of the front wall. A first guide plate, a second guide plate and a third guide plate are installed in the distributing chamber. This system makes the flow of the fluidizing air entered into the fluidizing chamber through each air cap uniform, and enhances the combusting efficiency of the coal powder in the fluidizing chamber.

An exhaust gas treatment apparatus which includes a denitration device, a dust collector, and a desulfurization device in order, respectively, in a flow path of exhaust gas discharged from a boiler, wherein a heavy-metal component removal device is provided in the exhaust gas flow path between the dust collector and the desulfurization device. This device is provided with: an absorption tower including a nozzle which sprays acidic absorption liquid on the exhaust gas, a tank which stores liquid which has absorbed a heavy metal, and a pump which supplies the nozzle with the liquid in the tank; a neutralizing tank which neutralizes the liquid drawn from the absorption tower; and a separator which separates the neutralized liquid into a solid and a liquid component. Since a small amount of heavy metal can be removed in the absorption tower, re-emission of the heavy metal by the desulfurization device is prevented.

The flue gas treatment system (1) comprises a reactor (2), a pre-separator (3) downstream of the reactor (2), a separator (4) such as a fabric filter downstream of the pre-separator (3), a humidifier (5) downstream of the separator (4), a supply (7) of a pure fresh reagent into the flue gas (FG) downstream of the pre-separator (3) and upstream of or at the separator (4).

A method for efficiently conveying impurities in a pressurized fluidized incinerator system is provided. Cleaning gas is supplied to an upper valve, and thereafter, the upper valve is driven so as to communicate an upper discharge device and a tank. The upper discharge device is driven so as to convey the impurities from the dust collector to the tank, and thereafter, the upper discharge device is stopped and the upper valve is driven so as not to communicate the upper discharge device and the tank. Thereafter, the supply of the cleaning gas to the upper valve is stopped.

In apparatus and method for waste treatment by pyrolysis, treated waste is flushed through a grid (18) to trap recyclable material in the pyrolysis chamber (24). Pyrolysis is carried out at a temperature of from 400-700 C. and off gases are dissolved in a solution in scrubber (13) for disposal in a water course. Water is introduced into the chamber as superheated steam via pipes (5) so as both to flush away treated material and clean the chamber. Recyclable waste is separated from non-recyclable by treating non-recyclable waste by pyrolysis, and flushing treated non-recyclable waste away through liquid exhaust (8). Apparatus is made as a modular, free-standing unit and comprises plugs for connection to an electricity supply, to a water supply, and to a sewage system (16) and has a chamber with a volume in the range 0.01-0.5 m.sup.3.

In a combustion system, a charge source is configured to cooperate with a collection plate and a director conduit to cause at least one particle charge-to-mass classification to be reintroduced to a flame for further reaction.

The combustion and flue gas treatment system includes a furnace for combusting a fuel with an oxidizer generating a flue gas, ducting for the flue gas connected to a NO.sub.x removal unit and a SO.sub.x removal unit, and a recirculation line for recirculating a part of the flue gas back to the furnace. The SO.sub.x removal unit is located upstream of the NO.sub.x removal unit with reference to the flue gas flow. The recirculation line is connected to the ducting downstream the SO.sub.x removal unit.