A straight fin for a device for recovering the waste heat of raw coke oven gas in the ascension pipe of the coke oven includes the straight fin body and a group of V-shaped notches disposed on the straight fin body. The depth h of the V-shaped notches is less than the width H of the straight fin body. The distances between the adjacent V-shaped notches increase from bottom to top in the longitudinal direction of the straight fin body. The present invention further provides a heat recovering device and a power generation device both including the straight fins. Moreover, the width, the angle, and the distances in the longitudinal direction of the V-shaped notches at the top of the straight fin are determined according to the temperature field distribution during use of the device.

A thermochemical treatment system for plastic and/or elastomeric waste is described, having three Reaction Units (1), (2) and (3) connected in series, being performed in each Reaction Unit, under positive pressure and low temperature (between 200 C. and 660 C.), one step of the thermochemical treatment process of the plastic and/or elastomeric waste without pretreatment (grinding, washing and drying), through the indirect heating by molten salt coils (5), with the generation of a solid fraction which is continuously drained by an outlet (104); a gas fraction which is treated in a Gas Scrubbing Unit (10) for release into the atmosphere, and a liquid fraction (molten plastic) which is subjected to an endothermic reaction under positive pressure (between 2 and 10 bar) and at temperature above 300 C., which generates a gas fraction that is fed into a Heat Exchanger (13), wherein the condensable gases are converted into fractionated combustible liquids of carbon chains from 5 to 35, and the non-condensable combustible gases are reused for heating the system modules, with the excess heat constituting a thermal battery.

This method for roasting biomass, including the flow by gravity of the biomass from the top towards the bottom of a column (4) with a counter-current of hot gases flowing from the bottom towards the top of the column (4), with the establishment of an increasing temperature gradient from the top towards the bottom of the column (4), the recovery of the gases at the top of the column and their recycling at the bottom of the column (4) by way of a gas circuit (12) so that the gases flow in a closed loop in the column (4) and the gas circuit (12), and the heating of the gases recovered by passing them through a heat exchanger (16) before their recycling at the bottom of the column (4).

This method for roasting biomass, including the flow by gravity of the biomass from the top towards the bottom of a column (4) with a counter-current of hot gases flowing from the bottom towards the top of the column (4), with the establishment of an increasing temperature gradient from the top towards the bottom of the column (4), the recovery of the gases at the top of the column and their recycling at the bottom of the column (4) by way of a gas circuit (12) so that the gases flow in a closed loop in the column (4) and the gas circuit (12), and the heating of the gases recovered by passing them through a heat exchanger (16) before their recycling at the bottom of the column (4).

The invention relates to a process for preparing ammonia gas and CO.sub.2 for urea synthesis. In the process of the invention, a process gas containing nitrogen, hydrogen and carbon dioxide as main components is produced from a metallurgical gas. The metallurgical gas consists of blast furnace gas, or contains blast furnace gas at least as a mixing component. The process gas is fractionated to give a gas stream containing the CO.sub.2 component and a gas mixture consisting primarily of N.sub.2 and H.sub.2. An ammonia gas suitable for the urea synthesis is produced from the gas mixture by means of ammonia synthesis. CO.sub.2 is branched off from the CO.sub.2-containing gas stream in a purity and amount suitable for the urea synthesis.

A pyrolysis system for synthesizing and utilizing synthesized gas and synthesized biochar material. The pyrolysis system may include at least one hopper configured to hold biomass. The pyrolysis system may also include at least one top-lit up-draft pyrolyzer operably engaged with the at least one hopper and configured to receive the biomass from the at least one hopper at a feeding rate to convert the biomass into a first byproduct and a second byproduct different than the first byproduct. The pyrolysis system may also include at least one static mixer operably engaged with the at least one conically-shaped pyrolyzer and configured to convert the first byproduct to a combustion energy source.

A pyrolysis system for synthesizing and utilizing synthesized gas and synthesized biochar material. The pyrolysis system may include at least one hopper configured to hold biomass. The pyrolysis system may also include at least one top-lit up-draft pyrolyzer operably engaged with the at least one hopper and configured to receive the biomass from the at least one hopper at a feeding rate to convert the biomass into a first byproduct and a second byproduct different than the first byproduct. The pyrolysis system may also include at least one static mixer operably engaged with the at least one conically-shaped pyrolyzer and configured to convert the first byproduct to a combustion energy source.

A system includes a heat exchange system and a power generation system. The heat exchange system includes first, second, and third heat exchangers each operable as a continuous source of heat from a delayed coking plant. The first and second heat exchangers heat first and second fluid streams to produce heated first and second fluid streams, respectively. The heated second fluid stream has a lower temperature and a greater quantity of heat than the heated first fluid stream. The third heat exchanger heats a third fluid stream to produce a heated third fluid stream that includes the heated first fluid stream and a hot fluid stream. The heated third fluid stream has a lower temperature than the heated first fluid stream. The power generation system generates power using heat from the heated second and third fluid streams.

A system includes a heat exchange system and a power generation system. The heat exchange system includes first, second, and third heat exchangers each operable as a continuous source of heat from a delayed coking plant. The first and second heat exchangers heat first and second fluid streams to produce heated first and second fluid streams, respectively. The heated second fluid stream has a lower temperature and a greater quantity of heat than the heated first fluid stream. The third heat exchanger heats a third fluid stream to produce a heated third fluid stream that includes the heated first fluid stream and a hot fluid stream. The heated third fluid stream has a lower temperature than the heated first fluid stream. The power generation system generates power using heat from the heated second and third fluid streams.

A system includes a heat exchange system and a power generation system. The heat exchange system includes first, second, and third heat exchangers each operable as a continuous source of heat from a delayed coking plant. The first and second heat exchangers heat first and second fluid streams to produce heated first and second fluid streams, respectively. The heated second fluid stream has a lower temperature and a greater quantity of heat than the heated first fluid stream. The third heat exchanger heats a third fluid stream to produce a heated third fluid stream that includes the heated first fluid stream and a hot fluid stream. The heated third fluid stream has a lower temperature than the heated first fluid stream. The power generation system generates power using heat from the heated second and third fluid streams.