Method and apparatus for heat treatment of industrial wastes

A method for the heat treatment of industrial wastes wherein at least some of the constituent materials of said wastes are subjected to combustion and/or to pyrolysis to produce a residue and flue gases, said method comprising the steps of supplying air at a first feed rate;

• supplying substantially pure oxygen at a second feed rate;
• mixing said air and oxygen to form an oxygenated combustion-supporting gas;
• supplying said oxygenated gas to said wastes for the heat treatment of the latter;
• sensing the temperature of the flue gases produced from said heat treatment;
• sensing the oxygen content of the flue gases produced from said heat treatment;
• adjusting said second feed rate in response to said sensed temperature to maintain the temperature of the flue gases within a predetermined range in the region 400.degree. to 1200.degree. C.;
• and adjusting said first and second feed rates in response to said sensed oxygen content to maintain a substantially constant oxygen content of said oxygenated gas so as not to vary the oxygen content of said flue gases.

A method for the heat treatment of industrial wastes wherein at least some of the constituent materials of said wastes are subjected to combustion and/or to pyrolysis to produce a residue and flue gases and wherein said flue gases are subjected to combustion, said method comprising the steps of supplying a mixture of air and substantially pure oxygen, constituting an oxygenated gas, to said wastes for the heat treatment of the latter;

• sensing at least one of the characteristics of the flue gases produced by the combustion and/or pyrolysis of said wastes, said characteristics including temperature and oxygen content;
• selectively adjusting the feed rate of at least one of said air and oxygen supplied to said wastes in response to said sensed characteristics;
• supplying a mixture of air and substantially pure oxygen to said flue gases for the combustion thereof;
• sensing at least one of the characteristics of the flue gases after combustion thereof, said last-mentioned characteristics including temperature and oxygen content;
• selectively adjusting the rate at which at least one of said air and said oxygen is supplied to said flue gases in response to said sensed last-mentioned characteristics;
• and utilizing the heat obtained from the combustion of said flue gases.

Apparatus for the heat treatment of industrial wastes, comprising a furnace having a waste treating section in which at least some of the constituent materials of said wastes are subjected to combustion and/or pyrolysis to produce flue gases;

• a source of air;
• a source of substantially pure oxygen;
• mixing means for mixing said air and oxygen to produce an oxygenated combustion-supporting gas;
• means for supplying said oxygenated gas to said waste treating section;
• sensing means for sensing at least one predetermined characteristic of said flue gases;
• and regulating means for regulating the rate at which at least one of said air and oxygen is supplied to said mixing means in response to said sensed characteristic.

Apparatus for the heat treatment of industrial wastes, comprising a furnace having a waste treating section in which at least some of the constituent materials of said wastes are subjected to combustion and/or pyrolysis to produce flue gases and a residue;

• a source of air;
• a source of substantially pure oxygen;
• mixing means for mixing said air and oxygen to produce an oxygenated gas;
• means for supplying said oxygenated gas to said waste treating section;
• sensing means for sensing at least one predetermined characteristic of said flue gases;
• air feed rate regulating means for regulating the rate at which air is fed to said mixing means;
• oxygen feed rate regulating means for regulating the rate at which oxygen is fed to said mixing means;
• and control means for controlling at least one of said regulating means in response to said sensed predetermined characteristic.

Apparatus for the heat treatment of industrial wastes comprising a furnace having a waste treating section in which at least some of the constituent materials of said wastes are subjected to combustion and/or pyrolysis to produce flue gases and a residue;

• a source of air;
• a source of substantially pure oxygen;
• mixing means for mixing said air and oxygen to produce an oxygenated gas;
• means for supplying said oxygenated gas to said waste treating section;
• temperature sensing means for sensing the temperature of said flue gases emitted by said waste treating section;
• oxygen sensing means for sensing the oxygen content of said flue gases;
• air feed rate regulating means for regulating the rate at which air is fed to said mixing means;
• oxygen feed rate regulating means for regulating the rate at which oxygen is fed to said mixing means;
• and control means for selectively controlling said oxygen feed rate regulating means in response to said sensed temperature to maintain the temperature of said flue gases within a predetermined range in the region 400.degree. to 1200.degree. C., and for selectively controlling both said oxygen feed rate regulating means and said air feed rate regulating means in response to said sensed oxygen content to maintain a substantially constant oxygen content of said oxygenated gas so as not to vary the oxygen content of said flue gases.

Apparatus for the heat treatment of industrial wastes comprising a furnace having a waste treating section in which at least some of the constituent materials of said wastes are subjected to combustion and/or pyrolysis to produce flue gases and a residue, and a flue gas combustion section in which said flue gases received from said waste treating section are subjected to combustion;

• a source of air;
• a source of substantially pure oxygen;
• first and second mixing means for mixing said air and oxygen to produce oxygenated gas;
• first means for supplying the oxygenated gas produced by said first mixing means to said waste treating section;
• second means for supplying the oxygenated gas produced by said second mixing means to said flue gas combustion section;
• first temperature sensing means disposed to sense the temperature of the flue gases exiting from said waste treating section;
• first oxygen sensing means disposed to sense the oxygen content of the flue gases exiting from said waste treating section;
• first air feed rate regulating means for regulating the rate at which air is fed to said first mixing means;
• first oxygen feed rate regulating means for regulating the rate at which oxygen is fed to said first mixing means;
• second temperature sensing means disposed to sense the temperature of the flue gases exiting from said flue gas combustion section;
• second oxygen sensing means disposed to sense the oxygen content of the flue gases exiting from said flue gas combustion section;
• second air feed rate regulating means for regulating the rate at which air is fed to said second mixing means;
• second oxygen feed rate regulating means for regulating the rate at which oxygen is fed to said second mixing means;
• control means for selectively controlling at least one of said first air and oxygen feed rate regulating means in response to at least one of the sensed temperature and oxygen content of the flue gases exiting from said waste treating section, and for selectively controlling at least one of said second air and oxygen feed rate regulating means in response to at least one of the sensed temperature and oxygen content of the flue gases exiting from said flue gas combustion section;
• and heat utilization means for receiving the flue gases exiting from said flue gas combustion section to utilize the heat of said flue gases.