摘要:
A heat exchanger, in particular for use in the contact group of a sulfuric acid plant, includes a chamber (2) in which a tube bundle (12) is arranged on a circular ring, wherein between the tube bundle (12) and a chamber casing (13) surrounding the tube bundle (12) a gas space (15) is formed, a gas supply opening (6) provided in the chamber casing (13) for introducing a gas into the gas space (15) substantially radially relative to the tube bundle (12), and a gas outlet opening which adjoins an interior space (16) enclosed by the tube bundle (12) in substantially axial direction. A uniform approach flow of the tube bundle (12) is achieved in that the center (Z R ) of the tube bundle (12) is offset with respect to the center (Z K ) of the chamber casing (13) in a direction opposite to the gas supply opening (6).
摘要:
A heat exchanger for a boiler comprises a plurality of exchanger conduits (2; 2') adjacent and parallel to an axis (X), that are fixed at opposite ends (2a, 2b) to manifold means (3, 4; 3', 4') arranged for conveying a fluid (F) to be heated through said exchanger conduits (2; 2'), characterised in that said exchanger conduits (2; 2') are arranged around said axis (X) so as to form an internal space (5; 5') arranged for receiving combustion fumes (S) entering said exchanger (1) and for enabling a substantially radial and uniform distribution of said combustion fumes (S) exiting through said exchanger conduits (2; 2').
摘要:
A fuel processing system (36) for a proton exchange membrane type fuell cell system comprises a heat exchanger (50) for transferring heat between first and second fluids (52) and (54) having a maximum operating mass flow rate through the heat exchanger (50) and mass flow rates that are substantially proportional to each other. The heat exchanger (50) provides essentially constant outlet temperatures for the first and second fluids (52,54) for all of the flow rates within the operating spectrum of the heat exchanger (50) without the use of an active control system.
摘要:
A heat-exchanger assembly (10), which can be advantageously employed as an intercooler for an air-charging system for an internal combustion engines includes a plurality of generally wedge-shaped coolant tubes (16,116) through which coolant is directed for effecting cooling of compressed air flowing about the tubes. In order to promote efficient operation, each of the wedge-shaped cooling tubes (16,116) includes a plurality of coolant passages (32,132) of substantially identical hydraulic diameter or cross-sectional area, thereby promoting uniform flow of coolant through each coolant tube. Each coolant tube (16,116) includes outer walls which may be of a substantially uniform thickness, or which may increase in thickness across the width of the tube.
摘要:
A shell and tube heat exchanger reactor with forced circulation is used to improve heat and mass transfer for exothermic liquid-liquid, gas-liquid and gas-liquid-solid reactions. Enhanced productivity and selectivity are obtained.
摘要:
A method to produce olefins comprising preheating a reaction feed, firing a conversion reactor, subjecting the reaction feed to a conversion in the conversion reactor, withdrawing a product gas from the conversion reactor, and cooling the product gas withdrawn from the conversion reactor is proposed, wherein said preheating and said cooling comprises transferring heat from said product gas or a part thereof to said reaction feed or a part thereof using a thermal energy recovery assembly comprising one or more inner passages and one or more outer passages coaxially surrounding said inner passage(s), said preheating and said cooling further comprises passing said reaction feed or said part thereof through said outer passage(s) of said thermal energy recovery assembly and passing said product gas or said part thereof through said inner passage(s) of said thermal energy recovery assembly, said thermal energy recovery assembly comprises one or more heat transfer enhancement structures to enhance heat transfer from said inner passage(s) to said outer passage(s), said firing the reactor comprises providing an oxidator gas at an oxidator gas temperature level of more than 400 °C using an oxidator gas preheating system and combusting a fuel gas comprising hydrogen using said oxidator gas at the fuel gas temperature level, and said thermal energy recovery assembly is configured to meet a set of operating constraints including a first temperature constraint relating to an outside temperature of a containment of said inner passage of said thermal energy recovery assembly and a second temperature constraint relating to an inside temperature of the containment of said inner passage of said thermal energy recovery assembly. Corresponding apparatus is also disclosed.