Abstract: A heat exchanger for a boiler, comprising, within a monolithic structure, at least one pair of mutually opposite manifolds connected by perforated pins inserted within a portion of space which is delimited by the structure and is designed to convey the products of combustion, the manifolds being adapted to provide the circulation of the fluid to be heated between an inlet connector and an outlet connector.

Abstract: An embodiment of the invention consists of a process heater with a radiant section and an overhead convection section, the radiant section having a vertical cylindrical, contiguous, helical, tubular coil, having a bottom process fluid inlet and top process fluid outlet. The process fluid coil is contained in a refractory lined enclosure of square cross section and is exposed to an up flowing stream of combustion products, generated by burning coal on a continuous, traveling, chain grate stoker. The stoker is located at the base of the radiant section, receives a continuous deposit of coarse coal, with a minimum of fines, from a hopper located at one end of the stoker chain grate and discharges essentially coal free ash at the opposite end of the chain grate, thru a nozzle provided with a water seal.

Abstract: A vertical polygonal heat exchange chamber includes an upper opening, a lower opening, and an enclosure formed between the upper and lower openings. The enclosure includes at least one tapered portion that narrows in a direction toward one of the openings. The tapered portion is lined with N first water tube panels arranged adjacent to and alternately with N second water tube panels, where N is an integer greater than two. Each of the first and second water tube panels is angled inwardly from the widest part of the tapered portion toward the interior of the enclosure, with each of the first water tube panels being angled inwardly to a greater degree than each of the second water tube panels.