EP-4741353-A1 - DRYING AND GRANULATING MACHINE

EP4741353A1EP 4741353 A1EP4741353 A1EP 4741353A1EP-4741353-A1

Abstract

The present invention relates to a drying and granulating machine, comprising: a housing, having a cylindrical shape, the housing having an inner wall and an outer wall spaced apart in the radial direction so as to define a heating space for accommodating a heating medium; and a rotor, the rotor comprising a plurality of blades protruding radially outward on the outer surface of the rotor. The plurality of blades include: a first blade, the shape of the first blade being designed to smear sludge on the inner surface of the inner wall facing the rotor; a second blade, the shape of the second blade being designed to promote mixing of sludge having different viscosities; a third blade, the shape of the third blade being designed to scrape off the dried sludge from the inner surface of the inner wall, so that the dried sludge falls off, and granulation of the sludge is promoted; and a fourth blade, the shape of the fourth blade being designed to bring the granulated sludge into contact with the inner surface of the inner wall, so that the granulated sludge is further dried, and the granularity of the granulated sludge is controlled to a set size and form.

Inventors

SHI, Ping
LI, HONGJUN
SHEN, Jiang
WU, ZHIBIN

Assignees

Suez Environmental Technology (Beijing) Company Limited

Dates

Publication Date: 20260513
Application Date: 20240820

Claims (14)

A drying granulator, which is characterized in that , the drying granulator comprises: a housing, having a cylindrical shape and comprising an inner wall and an outer wall spaced apart in a radial direction, thereby defining a heating space for containing a heating medium; a feed inlet, located at an end of the housing for receiving sludge and communicating with an inside of the housing; a discharge outlet, located at another end of the housing opposite to the end and communicated with the inside of the housing for discharging the sludge after being treated; and a rotor, arranged inside the housing, extending coaxially with the housing, and comprising a plurality of blades protruding outwards in a radial direction from an outer surface of the rotor, and the plurality of blades comprise: a first blade, spirally arranged on the outer surface of the rotor along a first section of a length of the rotor, the first section being adjacent to the feed inlet, and a shape of the first blade being designed to smear sludge on an inner surface of the inner wall facing the rotor; a second blade, spirally arranged on the outer surface of the rotor along the first section of the length of the rotor, the second blade being spaced apart from the first blade, and a shape of the second blade being designed to promote mixing of sludge with different viscosities; a third blade, spirally arranged on the outer surface of the rotor along a second section of the length of the rotor, the second section being continuous with the first section, and a shape of the third blade being designed to scrape dried sludge from the inner surface of the inner wall to make the dried sludge fall off, thus promoting granulation of the dried sludge; a fourth blade, spirally arranged on the outer surface of the rotor along the second section of the length of the rotor, the fourth blade being spaced apart from the third blade, and a shape of the fourth blade being designed to make granulated sludge contact with the inner surface of the inner wall, so as to further dry the granulated sludge and control a granularity of the granulated sludge to a set size and morphology.
The drying granulator according to claim 1, which is characterized in that the first blade comprises a first base plate, and a twisted blade and a bent blade arranged on opposite sides of the first base plate, the first base plate is arranged on the outer surface of the rotor, and the twisted blade and the bent blade are spaced apart from the inner surface of the inner wall, the twisted blade is twisted by a predetermined angle relative to the base plate, and the bent blade is obliquely bent by a predetermined angle relative to the base plate, so that during a rotation of the rotor, the twisted blade pushes the sludge to move towards the bent blade, and the bent blade smears the sludge on the inner surface of the inner wall.
The drying granulator according to claim 2, which is characterized in that the second blade comprises a second base plate, and a first twisted blade and a second twisted blade arranged on opposite sides of the second base plate, the second base plate is arranged on the outer surface of the rotor, the first twisted blade is twisted by a first angle relative to the second base plate, and the second twisted blade is twisted by a second angle relative to the second base plate, and the first angle is greater than the second angle, the first twisted blade is designed to propel sludge with increased viscosity, and the second twisted blade is designed to propel sludge with decreased viscosity, thus promoting the mixing of two kinds of sludge with different viscosities.
The drying granulator according to claim 3, which is characterized in that the third blade comprises a third base plate, and a third twisted blade and a straight blade arranged on two opposite sides of the third base plate, and the third base plate is arranged on the outer surface of the rotor, and the third twisted blade is twisted by a predetermined angle relative to the third base plate, the third twisted blade pushes the dried sludge to move to the straight blade, so that the straight blade scrapes the dried sludge from the inner surface of the inner wall to make the dried sludge fall off and promote the granulation of the dried sludge.
The drying granulator according to claim 4, which is characterized in that the fourth blade comprises a fourth base plate, a first bent blade and a second bent blade arranged on opposite sides of the fourth base plate, the fourth base plate is arranged on the outer surface of the rotor, the first bent blade is bent at a first angle relative to the fourth base plate, and the second bent blade is bent at a second angle relative to the fourth base plate, and the top ends of the first bent blade and/or the second bent blade facing the inner surface of the inner wall are provided with serrations, the first bent blade and the second bent blade are designed to make the granulated sludge contact with the inner surface of the inner wall, so that the granulated sludge can be further dried, and the granularity of the granulated sludge can be controlled to a set size and morphology through the serrations, so as to obtain shaped granulated sludge.
The drying granulator according to any one of claims 1-5, which is characterized in that the housing comprises a plurality of sections, the drying granulator comprises a heating pipeline, and the heating pipeline is respectively connected to each of the plurality of sections, thereby supplying the heating medium to each of the plurality of sections to the heating space.
The drying granulator according to claim 6, which is characterized in that the parameters of the heating medium supplied by the heating pipe to the plurality of sections are different from each other.
The drying granulator according to any one of claims 1-5, which is characterized in that the drying granulator comprises a drive system, and the drive system comprises: a drive motor; a speed reducer, coupled to the drive motor and the rotor, so as to transmit a driving force of the drive motor to the rotor to rotate the rotor.
The drying granulator according to claim 8, which is characterized in that the drying granulator further comprises a cooling system and a grease filler, the cooling system is coupled to the speed reducer and used for providing cooling for the drive system, and the grease filler is used for providing grease for a bearing of the drying granulator.
The drying granulator according to any one of claims 1-5, which is characterized in that the drying granulator further comprises a thermal imaging device installed on the housing, and the thermal imaging device is used for monitoring a temperature of the inner wall of the drying granulator and the sludge formation condition in real time, and the thermal imaging device comprises: an install bracket, installed to the housing, and a camera being installed to the install bracket; and a glass observation plate, installed to the housing, and the camera being installed to align with the glass observation plate, so that the inside of the housing can be monitored via the glass observation plate.
The drying granulator according to claim 10, which is characterized in that the thermal imaging device further comprises: a rinsing water filling port; a nozzle, connected to the rinsing water filling port and facing the glass observation plate, so that the nozzle receives rinsing water and sprays the rinsing water to the glass observation plate.
The drying granulator according to any one of claims 1-5, which is characterized in that the drying granulator further comprises a moisture measuring device arranged close to the discharge outlet, and the moisture measuring device is able to collect sludge samples from the drying granulator in real time for moisture detection.
The drying granulator according to any one of claims 1-5, which is characterized in that the drying granulator further comprises an axial displacement self-aligning roller bearing sleeved in the bearing box flange and the axial displacement self-aligning roller bearing comprises: an outer ring; a self-aligning transition ring, arranged at an inner side of the outer ring; an inner ring, arranged at an inner side of the self-aligning filter ring and configured to be able to move along an axial direction; and a cylindrical roller, arranged between the self-aligning filter ring and the inner ring and held by a roller cage.
The drying granulator according to any one of claims 1-5, which is characterized in that a plurality of ribs extending in the axial direction and spaced apart in the circumferential direction are arranged on the outer surface of the rotor, and the plurality of blades are installed on the plurality of ribs, and the plurality of ribs comprise first ribs and second ribs which are different from each other, and the first ribs and the second ribs are alternately with each other.

Description

CROSS-REFERENCE OF RELATED APPLICATIONS The present disclosure claims the priority of China application CN202311234815.1 filed in China National Intellectual Property Administration, China on September 22, 2023. TECHNICAL FIELD The embodiments of the disclosure relate to a drying granulator. BACKGROUND According to the data released by the Ministry of Housing and Urban-Rural Development in the "Urban and Rural Construction Statistical Yearbook", the national production of dry sludge in China reached 16.2179 million metric tons in 2021. Converted to dewatered sludge with 80% moisture content at wastewater treatment plants, the annual output amounts to 81.09 million metric tons. The proper treatment and disposal of sludge have become a critical priority following sewage treatment. Before final disposal or resource utilization (such as incineration, carbonization, gasification and building materials utilization), dewatered sludge generally needs to reduce its water content to below 40%. Drying is the main technical route to achieve this goal, so it is an important intermediate link in the whole chain of sludge treatment and disposal. In order to facilitate the disposal and recycling of sludge, in addition to reducing the water content of sludge, it is often needed to granulate the dried products, such as powdered dried sludge, to produce products with a certain morphology and granularity, so as to facilitate transportation, storage and disposal. Therefore, a granulation device is usually arranged after the drying device. Granulation is usually a process with high energy consumption and potential safety hazards, which not only increases investment, but also brings difficulties to operation. If granulation is synchronously completed in the drying process, it can show significant technical advantages. SUMMARY In order to overcome the above problems, the present disclosure provides a drying granulator, which includes: a housing, having a cylindrical shape and including an inner wall and an outer wall spaced apart in a radial direction, thereby defining a heating space for containing a heating medium; a feed inlet, located at an end of the housing for receiving sludge and communicating with an inside of the housing; a discharge outlet, located at another end of the housing opposite to the end and communicated with the inside of the housing for discharging the sludge after being treated; and a rotor, arranged inside the housing, extending coaxially with the housing, and including a plurality of blades protruding outwards in a radial direction from an outer surface of the rotor, and the plurality of blades include: a first blade, spirally arranged on the outer surface of the rotor along a first section of a length of the rotor, the first section being adjacent to the feed inlet, and a shape of the first blade being designed to smear sludge on an inner surface of the inner wall facing the rotor; a second blade, spirally arranged on the outer surface of the rotor along the first section of the length of the rotor, the second blade being spaced apart from the first blade, and a shape of the second blade being designed to promote mixing of sludge with different viscosities; a third blade, spirally arranged on the outer surface of the rotor along a second section of the length of the rotor, the second section being continuous with the first section, and a shape of the third blade being designed to scrape dried sludge from the inner surface of the inner wall to make the dried sludge fall off, thus promoting granulation of the dried sludge; a fourth blade, spirally arranged on the outer surface of the rotor along the second section of the length of the rotor, the fourth blade being spaced apart from the third blade, and a shape of the fourth blade being designed to make granulated sludge contact with the inner surface of the inner wall, so as to further dry the granulated sludge and control a granularity of the granulated sludge to a set size and morphology. Advantageously, the first blade includes a first base plate, and a twisted blade and a bent blade arranged on opposite sides of the first base plate, the first base plate is arranged on the outer surface of the rotor, and the twisted blade and the bent blade are spaced apart from the inner surface of the inner wall, the twisted blade is twisted by a predetermined angle relative to the base plate, and the bent blade is obliquely bent by a predetermined angle relative to the base plate, so that during a rotation of the rotor, the twisted blade pushes the sludge to move towards the bent blade, and the bent blade smears the sludge on the inner surface of the inner wall. Advantageously, the second blade includes a second base plate, and a first twisted blade and a second twisted blade arranged on opposite sides of the second base plate, the second base plate is arranged on the outer surface of the rotor, the first twisted blade is twisted by a first angle relative to the sec