Abstract:
A method controls mass and heat loading of sludge feed into a fluidized bed combustor (FBC) controlled via regulation of a polymer dosage or a sludge feed rate including: continuously monitoring at least one performance characteristic of the FBC; producing an input signal characteristic; analyzing the input signal and determining a first rate of change of the characteristic; generating an output signal based on the first rate of change to control addition of polymer to the FBC; generating a second output signal to control addition of sludge feed to the FBC; and determining a transition point between the addition of polymer and addition of sludge, which transition point is an upper limit of a first rate change to maintain flow so that the value of the characteristic is maintained proximate at the upper limit.
Abstract:
A method controls mass and heat loading of sludge feed into a fluidized bed combustor (FBC) controlled via regulation of a polymer dosage or a sludge feed rate including: continuously monitoring at least one performance characteristic of the FBC; producing an input signal characteristic; analyzing the input signal and determining a first rate of change of the characteristic; generating an output signal based on the first rate of change to control addition of polymer to the FBC; generating a second output signal to control addition of sludge feed to the FBC; and determining a transition point between the addition of polymer and addition of sludge, which transition point is an upper limit of a first rate change to maintain flow so that the value of the characteristic is maintained proximate at the upper limit.
Abstract:
An environmentally acceptable and effective method for thermal destruction of Spent Potliner (SPL) by Fluidized Bed Combustion (FBC) has been established. This method has overcome problems associated with ash agglomeration, ash leachate character and emission control, the primary obstacles for applying FBC to the disposal of SPL and like solid fuels. Specifically, "recipes" of appropriate additives (fuel blends) are proposed. A mixture of lignite, limestone and SPL in an appropriate proportion has proven to notably increase the agglomeration temperature of the ash, allowing this low-melting waste to be destroyed continuously by FBC. Ash leachate character is modified by control of ash chemistry to ensure that fluoride anions and metallic cations are at or below acceptable limits.
Abstract:
A method controls mass and heat loading of sludge feed into a fluidized bed combustor (FBC) controlled via regulation of a polymer dosage or a sludge feed rate including: continuously monitoring at least one performance characteristic of the FBC; producing an input signal characteristic; analyzing the input signal and determining a first rate of change of the characteristic; generating an output signal based on the first rate of change to control addition of polymer to the FBC; generating a second output signal to control addition of sludge feed to the FBC; and determining a transition point between the addition of polymer and addition of sludge, which transition point is an upper limit of a first rate change to maintain flow so that the value of the characteristic is maintained proximate at the upper limit.
Abstract:
A method of incinerating sludge in a combustor is disclosed including establishing at least one target performance characteristic of the combustor; introducing the sludge into the combustor as primary fuel; monitoring at least one performance parameter of the combustor; calculating an actual performance characteristic based on the performance parameter; and adjusting the quantity and/or quality of fuel introduced into the combustor in response to a monitored performance characteristic to substantially maintain the target performance characteristic. The apparatus for incinerating sludge includes a combustor adapted to receive sludge as fuel and incinerate the sludge; a sensor that monitors at least one performance parameter of the combustor; and a controller connected to the combustor and the sensor that 1) establishes at least one target performance characteristic of the combustor, 2) calculates an actual performance characteristic based on the performance parameter and 3) adjusts quantity and/or quality of fuel introduced into the combustor in response to a monitored performance characteristic to substantially maintain the target performance characteristic.
Abstract:
The process is by injection of calcium chloride into the combustor and lowering the flue gas temperature in sufficient time to enhance oxidation of mercury and nitrogen oxides into more soluble products prior to their absorption in a wet scrubber. The additive also increases the alkalinity and the pH of the scrubber water, therefore, favorably increasing the absorption of the pollutants. The flue gas is then cooled to ambient temperature or less to enhance the removal of mercury.