Pitch production systems utilizing coal tar or decant oil for coal or petroleum based pitch are disclosed. Total pitch production yields are increased by heat treating distillate fractions from the pitch production process. A heat treatment system and process are disclosed in embodiments. The heaviest distillates having the highest molecular weights are subjected to heat treatment, though other embodiments contemplate heat treating a variety of combined distillate fractions. The heat treatment systems require heat soaking the distillate(s) at elevated temperatures of 459-535° C. at a near-constant temperature with near-uniform flow. A fraction of the heat-treated distillate may be reintroduced to the pitch production system as part of a continuous process.

Pitch production systems utilizing coal tar or decant oil for coal or petroleum based pitch are disclosed. Total pitch production yields are increased by heat treating distillate fractions from the pitch production process. A heat treatment system and process are disclosed in embodiments. The heaviest distillates having the highest molecular weights are subjected to heat treatment, though other embodiments contemplate heat treating a variety of combined distillate fractions. The heat treatment systems require heat soaking the distillate(s) at elevated temperatures of 459-535° C. at a near-constant temperature with near-uniform flow. A fraction of the heat-treated distillate may be reintroduced to the pitch production system as part of a continuous process.

An atmospheric-vacuum heat exchange system with a winding-tube heat exchanger, has a first and second heat exchanging group; a primary distillation tower (4) or flash tower; an atmospheric furnace (5); an atmospheric tower (6); a vacuum furnace (7) and a vacuum tower (8); each winding-tube heat exchanger has a shell-pass cylinder (370), a first and second shell-pass connecting tube (371,372), a first and second tube plate (330,340), a plurality of first and second tube box (310,320), a plurality of heat exchange tubes (360) spirally wounded with multiple spiral tube layers; the number of the first and second tube box (310, 320) are respectively N, and each spiral tube layer has N group(s) of the wounded heat exchange tubes (360), N is a natural number greater than or equal to 1. The loss of heat exchanger is reduced.

An atmospheric-vacuum heat exchange system with a winding-tube heat exchanger, has a first and second heat exchanging group; a primary distillation tower (4) or flash tower; an atmospheric furnace (5); an atmospheric tower (6); a vacuum furnace (7) and a vacuum tower (8); each winding-tube heat exchanger has a shell-pass cylinder (370), a first and second shell-pass connecting tube (371,372), a first and second tube plate (330,340), a plurality of first and second tube box (310,320), a plurality of heat exchange tubes (360) spirally wounded with multiple spiral tube layers; the number of the first and second tube box (310, 320) are respectively N, and each spiral tube layer has N group(s) of the wounded heat exchange tubes (360), N is a natural number greater than or equal to 1. The loss of heat exchanger is reduced.

The present invention provides a process for production of graphite coke from an admixture of coal and petroleum-based hydrocarbons. This particularly describes a process wherein a mixture of coal tar pitch and hydrocarbon feedstock such as CLO is purified in a solvent treatment step and the purified mixed feedstock is subjected to thermal cracking to produce high quality graphite/needle coke. This process also provides a synergy in improved coke quality coke formation while using an admixture of coal tar pitch and CLO while subjected to common purification and coking steps.

The present invention provides a process for production of graphite coke from an admixture of coal and petroleum-based hydrocarbons. This particularly describes a process wherein a mixture of coal tar pitch and hydrocarbon feedstock such as CLO is purified in a solvent treatment step and the purified mixed feedstock is subjected to thermal cracking to produce high quality graphite/needle coke. This process also provides a synergy in improved coke quality coke formation while using an admixture of coal tar pitch and CLO while subjected to common purification and coking steps.

A method and device are provided for purifying and recycling water vapor from a coal drying process. Included are a temperature-lowering and dehumidifying process, a flash distillation stripping process, and a vacuum condensing process. A condensing tower receives a temperature-lowered exhaust gas with high humidity from a cooling tube and a condensed water of 5˜60° C. from a flash distillation tank, allowing the exhaust gas and the condensed water to contact each other in a vapor-liquid reverse manner, to lower the temperature and dehumidify the exhaust gas. The flash distillation tank performs a vacuum flash distillation to the condensing water pumped therein from the condensing tower. Water vapor of 5˜60° C. evaporated through flash distillation in the flash distillation tank enters into the demisting washer to be dehumidified and then is condensed. The condensed water in the vapor condenser is transferred into a recycled water tank. Non-condensable gas is discharged out.

A method and device are provided for purifying and recycling water vapor from a coal drying process. Included are a temperature-lowering and dehumidifying process, a flash distillation stripping process, and a vacuum condensing process. A condensing tower receives a temperature-lowered exhaust gas with high humidity from a cooling tube and a condensed water of 5˜60° C. from a flash distillation tank, allowing the exhaust gas and the condensed water to contact each other in a vapor-liquid reverse manner, to lower the temperature and dehumidify the exhaust gas. The flash distillation tank performs a vacuum flash distillation to the condensing water pumped therein from the condensing tower. Water vapor of 5˜60° C. evaporated through flash distillation in the flash distillation tank enters into the demisting washer to be dehumidified and then is condensed. The condensed water in the vapor condenser is transferred into a recycled water tank. Non-condensable gas is discharged out.

An aroma diffuser using an aroma capsule is disclosed to include a hollow housing including a first opening on a top side thereof, a second opening on a bottom side thereof and an integrated holder member downwardly inwardly extended from a top side thereof and defining therein a holding chamber facing toward the first opening, a heat conduction device mounted in the holding chamber, and a heating element mounted at a bottom side of the heat conduction device and kept in contact with the heat conduction device. Thus, an aroma capsule can be placed in the holding chamber and heated by the heating element to release fragrant vapor. After the aroma contained in the aroma capsule is used up, the aroma capsule can be replaced conveniently and rapidly.

Embodiments described herein provide a method, comprising reducing pH of a glycol vaporization separator purge stream to form an acid stream; distilling the acid stream to form an overhead stream and a bottoms stream; and recycling the bottoms stream to the vaporization separator.