Abstract: A basket for an air preheater includes two metallic frames each having two corner pieces and two connector pieces. For each frame, one of the connector pieces is secured to one end of each of the corner pieces and another of the connector pieces is secured to an opposite end of each of the corner pieces thereby forming a rectangular opening in each frame. The basket includes two heavy gauge metallic sheets that are secured to the corner pieces, thereby spacing the frames equally apart from and parallel to one another thereby forming a channel between two of the sheets.

Abstract: A method for improving effectiveness of a steam generator system includes providing air to an air preheater in excess of that required for combustion of fuel and providing the air at a mass flow such that the air preheater has a cold end metal temperature that is no less than a water dew point temperature in the air preheater and such that the cold end metal temperature is less than a sulfuric acid dew point temperature. The method includes mitigating SO3 in the flue gas which is discharged directly from the air preheater to a particulate removal system and then directly into a flue gas desulfurization system. Flue gas reheat air is fed from the air preheater to heat the flue gas prior to entering a discharge stack to raise the temperature of the flue gas to mitigate visible plume exiting and to mitigate corrosion in the discharge stack.

Abstract: An insulation retaining assembly for a high temperature rotary pre-heater having a cold-end rotor and a hot-end rotor includes a plurality of elongate retainer elements. Each of the retainer elements has a root end adapted to be held in fixed relationship to the cold-end rotor and a distal end proximate to the hot-end rotor. Portions of each of the plurality of retainer elements are adapted for circumferential movement.

Abstract: A roller mill system includes a vessel having an inlet, an outlet, a grinding zone and a classifier zone. The grinding zone includes a grinding assembly configured for grinding the material into fine particles. The grinding zone also includes a rejects capture and discharge system that includes one or more discharge conduits for conveying rejects away from the vessel. The rejects capture and discharge system includes: 1) a collection trough located under the grinding assembly and in communication with one of the discharge conduits, for discharging rejects from the grinding zone; and/or 2) a turbine classifier mounted in the classifier zone. The turbine classifier is rotatable about a central axis. Another outlet is formed in a side wall of the classifier zone. The turbine classifier is configured to expel the rejects radially outward therefrom, through the side wall outlet and into another one of the discharge conduits.

Abstract: Heat transfer sheets (70) for a rotary regenerative heat exchanger (10) have a alternating first and second undulation surfaces (71,81). The first and second undulation surfaces (71,81) are composed of parallel ridges (75,85) angled in alternating directions. When the heat transfer sheets (70) are stacked, they create passageways (79) between them that direct air/gas through them. The ridges (75,85) redirect the air flow near the surface of the heat transfer sheet (70) imparting turbulence reducing laminar flow to improve heat transfer. The heat transfer sheets (80) employ curved ridges (95) having valleys (97) between them that define passageways (99) that constantly redirect the air/gas flow minimizing turbulence, creating efficient heat transfer.

Abstract: A heat transfer sheet for a rotary regenerative heat exchanger includes a plurality of rows of heat transfer surfaces each being aligned with a longitudinal axis extending between first and second ends thereof. The heat transfer surfaces have a height relative to a central plane of the heat transfer sheet. The heat transfer sheet includes one or more notch configurations for spacing the heat transfer sheets apart from one another. Each of the notch configurations are positioned between adjacent rows of heat transfer surfaces. The notch configurations include one or more lobes connected to one another, positioned in a common flow channel and extending away from the central plane and one or more lobes extending away from the central plane in an opposite direction and being coaxial. The lobes have height a relative to the central plane that is greater than the height of the heat transfer surfaces.

Abstract: A thermally efficiency regenerative air preheater 250 extracts more thermal energy from the flue gas exiting a solid fuel fired furnace 26 by employing an alkaline injection system 276. This mitigates acid fouling by selectively injecting different sized alkaline particles 275 into the air preheater 250. Small particles provide nucleation sites for condensation and neutralization of acid vapors. Large particles are injected to contact and selectively adhere to the heat exchange elements 542 and neutralize liquid acid that condenses there. When the deposit accumulation exceeds a threshold, the apparatus generates and utilizes a higher relative percentage of large particles. Similarly, a larger relative percentage of small particles are used in other cases. Mitigation of the fouling conditions permits the redesign of the air preheater 250 to achieve the transfer of more heat from the flue resulting in a lower flue gas outlet temperature without excessive fouling.

Abstract: A roller for forming heat transfer elements may include a central shaft and a plurality of roller elements. The plurality of roller elements may be stacked on the central shaft. Each roller element defines an outer periphery, which is configured to include a geometrical characteristic thereacross. The stacked roller elements, either stacked on the central shaft or stacked without using the central shaft, configures the roller with a circumferential surface corresponding to the geometrical characteristic of the stacked roller elements, to form the heat transfer elements corresponding to the circumferential surface.

Abstract: A seal assembly includes a leaf assembly and a supplemental leaf assembly. The leaf assembly includes a first leaf having a first base section. The first base section defines a first fastening area for securing the first leaf to a diaphragm of the preheater. The first leaf has a first elongate section extending away from the first base section and terminating at a first distal end thereof. The leaf assembly further includes a second leaf that engages a portion of the first leaf. The second leaf has a second base section. The second base section defines a second fastening area for securing the second leaf to the diaphragm. The second leaf has a second elongate section extending away from the second base section and terminating at a second distal end thereof. The supplemental leaf assembly is secured to the first leaf and slidingly engaging the second leaf.

Abstract: A heat transfer sheet [60,160,260,360] for a rotary regenerative heat exchanger is shaped to include sheet spacing features [59], which provide spacing between adjacent heat transfer sheets [60,160,260,360], and undulation surfaces [68,70] (corrugations) in the sections between the sheet spacing features [59]. The undulation sections [68,70] are constructed of regularly spaced lobes [64,72] extending at an angle with respect to the spacing features [59]. The undulating sections [68,70] impart turbulence in the air or flue gas flowing between the heat transfer sheets [60, 160, 260, 360] to improve heat transfer. The heat transfer sheets [60,160,260,360] may include undulating surfaces that differ in angle of their lobes [64,72].

Abstract: A bowl mill for producing coarse ground particles has a substantially closed body, a bowl assembly, a plurality of grinding rolls, and a coarse particle transport enabling area. The substantially closed body has an interior area. The bowl assembly includes a rotatable grinding table mounted for rotation in a direction of rotation in the interior area. The grinding table has a grinding surface thereon. The plurality of grinding rolls are positioned proximate the grinding surface. The grinding rolls and the grinding surface define a grinding area therebetween. The coarse particle transport enabling area is located radially outward from the grinding area. The coarse particle transport enabling area is configured to allow the coarse particles to freely exit the grinding area and to mitigate the coarse particles from being circulated back into the grinding area.

Abstract: A stack of heat transfer sheets includes one or more first sheet which includes a first undulating surface formed by first lobes that are parallel to each other and oriented at a first angle. The first sheets include a second undulating surface formed by second lobes that are parallel to each other and oriented at a second angle, different from the first angle. The first sheets include a third undulating surface formed by third lobes extending from one or more ends of the first sheet and terminating at an intermediate point between the end and an opposing end thereof. The third lobes are parallel to each other and parallel to the direction of flow through the stack. The stack includes one or more second sheets defining a plurality of sheet spacing features which engage a portion of the first sheet.

Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.