A temperature-adjustable four-effect dehumidifying and drying system, having at least two sets of dehumidification heat pump assemblies and a set of auxiliary heat exchange assembly, wherein the dehumidification heat pump assemblies have at least two refrigerant modules and an air module, the auxiliary heat exchange assembly is formed by connecting at least two heat exchangers (4, 12) in series by means of a circulation pipeline, and the circulation pipeline is provided with a refrigerant inlet and a refrigerant outlet.

The present invention relates to a drying apparatus for evaporating volatile constituents from a starting material to be dried, to a process for producing an isocyanate using this drying apparatus and to the use of the drying apparatus for drying distillation bottoms streams, oil-containing waste, waste paint or coating materials, sewage sludges, mineral substances and coal slurries contaminated with organic compounds. In the drying apparatus the evaporated constituents (vapours) are passed into a condenser via a vapor dome and a vapor conduit. The drying apparatus has the feature that partial condensation of the vapours in the vapor dome and/or in the vapor conduit is intentionally allowed or induced during operation, and condensed constituents of the vapours are discharged from the drying apparatus via means installed for this purpose in the vapor dome and/or the vapour conduit.

An apparatus is provided for feeding slurry to a recycling or slurry treatment process at an elevated location. The apparatus includes a reception hopper for receiving the slurry from a transport vehicle, and a bucket elevator for conveying the slurry from a loading zone, in communication with the reception hopper, to a discharge zone at an elevated location. The reception hopper includes a trough having parallel side walls and a bottom wall. The loading zone of the bucket elevator communicates with a first end of the trough, the trough including a movable wall extending perpendicular to the side walls of the reception hopper and being movable towards the first end of the trough to urge slurry towards the loading zone of the bucket elevator.

A technique, method and system for drying a solid waste stream in a pyrolysis recycling installation, including drying the waste stream in a first dryer, feeding the partially dried waste stream from the first dryer to a second dryer, further drying the waste stream in the second dryer to produce a dried waste stream, and feeding the dried waste stream from the second dryer to a pyrolysis unit, wherein the first and second dryers dry the waste stream primarily, or exclusively, using heat generated from the pyrolysis unit.

A drying system includes a disk contact dryer, which includes an inlet for the sewage sludge, a drying chamber for temporarily accommodating the sewage sludge, multiple disks in the drying chamber, a drive for rotating the disks at a defined rotational speed, a heater for heating the disks, an outlet for the sewage sludge dried in the drying chamber, and an incineration system for the dried sludge. The drying system includes an input sensor for determining the initial moisture of the sewage sludge, an output sensor for determining the final moisture of the sewage sludge, and a controller for regulating the rotational speed of the disks and/or the heat output of the heater and/or the amount of sewage sludge entering the inlet, and/or the amount of dry sewage sludge exiting the outlet based on the measurements of the input sensor and of the output sensor.

Disclosed is a slurry drying plant (1) comprising a slurry inlet (2) for feeding slurry to the slurry drying plant (1) and two or more meshing screw conveyors (3, 4) arranged to at least partly divide the slurry while conveying the slurry in a transport direction from the slurry inlet (2) to a slurry outlet (5). The slurry drying plant (1) further includes slurry heating means (6) comprising means for passing superheated steam substantially at atmospheric pressure past the slurry and the two or more meshing screw conveyors (3, 4), while they are conveying the slurry. Furthermore, a method for drying slurry and use of a slurry drying plant (1) is disclosed.

A method and apparatus for direct drying of inorganic sludge with a drum drawing process, comprising the following steps: 1) drum mixed drying of slag and sludge: respectively conveying the slag and sludge into a drum (1) in proportion, completing mixing, heat exchange, dehydration, cooling and crushing of the slag and sludge under the rolling action of the drum (1) and a steel ball to achieve cooling, crushing and drying of the slag and sludge, and directly discharging the obtained mixture; 2) slag and sludge separation: separating the steel slag and dry sludge in a manner of combining screening and rotary separation; 3) tail gas treatment: treating dusts, sulfides and organic compounds in tail gas generated by the dry sludge by using wet alkali washing and activated carbon adsorption, and discharging the treated tail gas; and 4) tailing sludge treatment: generating steam and dusts in the drum treatment of the slag and sludge, allowing dusts to enter a tail gas treatment device (4) with steam, aggregating the dusts after wet washing or spraying, and then conveying into a tailing sludge blending device (5) by means of a conveying device, mixing and stirring the tailing sludge and original sludge, conveying the obtained mixture into the drum (1), and drying the mixture to realize zero discharge of undried sludge.

Systems and processes provide for a thermal process to transform sludge (and a variety of other natural waste materials) into electricity. Dewatered sludge and other materials containing a high amount of latent energy are dried into a powdered biofuel using a drying gas produced in the system. The drying gas is recirculated and is heated by the biofuel produced in the system, waste heat (from turbines or internal combustion engines), gas (including natural gas or digester gas) and/or oil. The biofuel is combusted in a boiler system that utilizes a burner operable to burn biofuel and produce heat utilized in a series of heat exchangers that heat the recirculating drying air and steam that powers the turbines for electricity production.

A device for drying sewage sludge having a modular design composed of standard containers, the standard containers being disposed behind and optionally on top of one another. Slabs including heating lines are introduced on top of one another, in multiple levels, into the standard containers, serving as drying surfaces. Linear conveyors including deflections in a first and a last container distribute the sewage sludge across a width of the drying surfaces, turn and loosen the sewage sludge, and move this successively back and forth over the drying surfaces disposed on top of one another.

Devices, systems, and methods for drying a bulk waste product, such as animal waste, having a moisture content of 95% or more water can include a trough configured to receive the bulk waste product and to dispense it in a form suitable for convective drying, one or more conveyors having an air-permeable conveyor belt, each conveyor receiving the waste product from the trough and transporting the waste product along a transport path; and one or more air moving devices (AMDs) that pass air through the air-permeable conveyor belt and across the waste product as it is transported along the transport path to transform the bulk waste product into a dried waste product having a moisture content of about 5% to about 20%, inclusive.