A pressurized fluidized bed combustor (PFBC) and method of operation. A heated diluent is used alone or in combination with adjustments to a combustor gas velocity, to manage the bed temperature and keep it within allowable ranges. The diluent can be taken from the combustor flue gas, and recycled and reheated through the fluidized bed.

A heat exchanger including a pipe bundle to guide a fluid between first and second pipe connectors, the pipes being distributed in layers of pipes, wherein pipes of each of the layers of pipes each includes two bends, wherein a length of a flow path section is at least 1.7 times greater than lengths of two other flow path sections. A first bend of the two bends is provided between the longer flow path section and a first of the shorter flow path section, and wherein a second of the two bends is provided between the first, shorter flow path section and the other shorter flow path section, and wherein each of the layers of pipes includes two pipe subgroups. The second bend in one of the pipe subgroups in the pipe layer is opposite to the second bend-in the other pipe subgroup of the same pipe layer.

The present invention relates to a working fluid evaporator for an OTEC plant, comprising an evaporator body extending along a longitudinal axis, a bundle of evaporators transporting hot water and comprising a plurality of evaporation elements, a sprinkling system extending above the bundle of evaporators and a casing covering the bundle of evaporators and the sprinkling system, an evacuation area being formed between end columns of the evaporator elements and the casing. The evaporator further comprises a redistribution system configured to collect the working fluid in a liquid state in the evacuation area and direct it to interior evaporator elements.

The present invention relates to a working fluid evaporator for an OTEC plant, comprising an evaporator body extending along a longitudinal axis, a bundle of evaporators transporting hot water and comprising a plurality of evaporation elements, a sprinkling system extending above the bundle of evaporators and a casing covering the bundle of evaporators and the sprinkling system, an evacuation area being formed between end columns of the evaporator elements and the casing. The evaporator further comprises a redistribution system configured to collect the working fluid in a liquid state in the evacuation area and direct it to interior evaporator elements.

A boiler includes a steam drum, an intermediate drum, and a lower drum. Each drum is divided into a clean section and a concentrated section. A channel that is fluidly connected to the clean section also runs down one side of the concentrated section in the intermediate drum and the lower drum. The presence of the channels permits low-quality feedwater tubes and high-quality feedwater tubes to be arranged in parallel rows next to each other.

Disclosed herein is a once-through evaporator comprising an inlet manifold; one or more inlet headers in fluid communication with the inlet manifold; one or more tube stacks, where each tube stack comprises one or more substantially horizontal evaporator tubes; the one or more tube stacks being in fluid communication with the one or more inlet headers; one or more outlet headers in fluid communication with one or more tube stacks; an outlet manifold in fluid communication with the one or more outlet headers; and a plurality of flow control devices to dynamically control the fluid flow to a respective inlet header.

Disclosed herein is a once-through evaporator comprising an inlet manifold; one or more inlet headers in fluid communication with the inlet manifold; one or more tube stacks, where each tube stack comprises one or more substantially horizontal evaporator tubes; the one or more tube stacks being in fluid communication with the one or more inlet headers; one or more outlet headers in fluid communication with one or more tube stacks; an outlet manifold in fluid communication with the one or more outlet headers; and a plurality of flow control devices to dynamically control the fluid flow to a respective inlet header.

A heat exchanger apparatus for receiving water from a steam drum (1) and providing steam and heated unevaporated liquid water to the steam drum includes a first evaporator (EVAP-1) and a second evaporator (EVAP-2). The first evaporator can receive water from a steam drum via a first feed conduit (9) and the second evaporator can receive water from a second feed conduit (11). Both evaporators can output heated fluid to the steam drum via a combined evaporator output conduit (13). Each first evaporator passageway (14) only makes a single pass through a gas duct (15) having a heated gas flow (7) passing therethrough while each second evaporator passageways (24) can make one or more passes through the gas duct for transferring heat from the gas to the fluid within the evaporators. A portion of the first feed conduit can also have a pre-specified volume a pre-specified height below the first inlet (10).

A heat exchanger apparatus for receiving water from a steam drum (1) and providing steam and heated unevaporated liquid water to the steam drum includes a first evaporator (EVAP-1) and a second evaporator (EVAP-2). The first evaporator can receive water from a steam drum via a first feed conduit (9) and the second evaporator can receive water from a second feed conduit (11). Both evaporators can output heated fluid to the steam drum via a combined evaporator output conduit (13). Each first evaporator passageway (14) only makes a single pass through a gas duct (15) having a heated gas flow (7) passing therethrough while each second evaporator passageways (24) can make one or more passes through the gas duct for transferring heat from the gas to the fluid within the evaporators. A portion of the first feed conduit can also have a pre-specified volume a pre-specified height below the first inlet (10).

A heat exchanger tube block is stacked on another heat exchanger tube block in an upper-lower direction and connected to the another heat exchanger tube block. The heat exchanger tube block includes: a duct casing wherein exhaust gas containing dust flows in the upper-lower direction; a heat exchanger tube in the duct casing extends horizontally; an inlet header connects to the heat exchanger tube inlet; an outlet header connected to an outlet of the heat exchanger tube; and a vibration transmitting member transmitting vibration, applied to an upper end part of the vibration transmitting member, to the heat exchanger tube to make the dust accumulating on the heat exchanger tube fall. A lower end of the duct casing is formed horizontally. The inlet header is located higher than the lower end of the duct casing. The outlet header is located higher than the lower end of the duct casing.