EP4378591A1

EP4378591A1 - Valuable phase discharge system for centrifuges

Info

Publication number: EP4378591A1
Application number: EP22210421.8A
Authority: EP
Inventors: Erdem SAGLAM; Muhammet Alihan YILMAZ; Feyzullah Umut OZGUC
Original assignee: Haus Makina Sanayi Ticaret AS
Current assignee: Haus Makina Sanayi Ticaret AS
Priority date: 2022-11-30
Filing date: 2022-11-30
Publication date: 2024-06-05

Abstract

The present invention relates to a system that ensures that the water fed into the rotating bowl group before the solid discharge operation is at a constant flow rate and temperature, allowing the valuable phase to be extracted to the greatest extent possible.

Description

Technical Field of the Invention

The present invention relates to a system that ensures that the control liquid, hereinafter that is mentioned as water, fed into the rotating bowl group before the solid discharge operation is at a constant flow rate and a constant temperature so that the valuable phase can be taken out at the maximum level.

Background of the Invention

Centrifugal separators are generally used for the separation of liquids and/or solids from a liquid mixture. During operation, a fluid mixture that is about to be separated is introduced into a rotating bowl and due to the centrifugal forces, heavy particles or denser liquid, such as water, accumulate at the periphery of the rotating bowl whereas less dense liquid accumulates closer to the central axis of rotation. This allows for the collection of the separated fractions, e.g., using different outlets arranged at the periphery and/or close to the rotational axis, respectively.
There is a rotating bowl group that separates liquid-liquid for centrifuge machines. The inner volume of the rotating bowl group is filled with the product (liquid-liquid mixture) that is fed continuously. Product feeding can be interrupted at the end of the day or certain intervals according to the process requirements. When the product feed is interrupted, the bowl group's inner volume is still filled with the product. This product (liquid-liquid with or without solid mixture) consists of two different liquids with or without solids, generally defined as light phase, heavy phase, and solid phase, and generally, the light phase refers to the valuable phase. During the process, the valuable phase inside of the bowl volume needs to be removed from the machine. Otherwise, when the inner volume of the machine is completely emptied by solid discharge operation at the end of the process, all the valuable phase is lost. Currently, water is fed to the machine at a certain temperature, flow rate, and time to remove this valuable phase from the machine. However, the flow of this fed water varies according to the facility where the machine is located. Even if the flow rate of the water in the line of the facility is sufficient on paper, if the water is used in another machine simultaneously before the solid discharge operation, the flow rate of the water decreases, and some of the valuable phase is lost.
Another situation is that the hot water line in the facility is not sufficient. Before the solid discharge process, water is supplied to the centrifuge for a certain period in order to displace the valuable phase from outside. The temperature of the supplied water is approximately the same as the product being processed. The water fed to remove the valuable phase from the machine cannot be fed at the same temperature during the feeding period and cools down after a while. The light phase colliding with the chilled water forms an emulsion and mixes with the heavy phase. Therefore, the cooled water does not ensure that the valuable phase is removed from the machine.
The document numbered " US4343431A " in the state of the art is related to centrifugal separators of the kind having sludge ports at the rotor periphery to be opened during operation and separate outlets for the separated heavier liquid phase and the separated lighter liquid phase. To reduce the losses of valuable lighter liquid phase during total discharge or partial discharge of the separator by opening the sludge ports, the centrifuge is provided with an overflow device connected to the heavy phase outlet, said overflow device having an inner annular overflow. Here, by reducing the heavy phase outlet area, the valuable product is discharged by feeding the product displacement water at a lower flow rate than normal. By leaving an overflow path for high flow rates, the fed water is prevented from coming from the light phase. The system described by the invention does not interfere with the water properties fed to the machine such as flow rate and temperature, it only allows the machine to operate in a wider water supply range. also, it cannot solve the imbalances and inadequacies in the water lines in the facilities.
The document numbered " CN216261367U " in the state of the art is related to the technical field of disc-type separating machines, especially related to automatic adjustable water sealing water systems for disc-type separating machines. An automatically adjustable water sealing system for a disc separator comprises a rotating drum, a feeding pipe, a separation cavity, a slag discharge port, a water outlet pipe, a light phase zone, slag phase zone. By feeding water to the heavy phase at the time of discharge with the lower water outlet pipe of the drum, it is ensured that the valuable product, which is close to the inner diameter, is prevented from being thrown out. However, it does not provide a solution for removing the valuable product from the drum. It cannot solve the imbalances and inadequacies in the water lines in the facilities.
In the current situation, the flow rate and temperature of the water fed vary depending on the capabilities of the facility where the machine is installed, regardless of the machine. This situation causes the valuable phase in the rotating bowl group to be lost depending on external factors and cannot be taken out of the machine at the desired level.
As a result, new technology is needed due to the above-mentioned negativities and the inadequacy of existing solutions on the subject.

Summary of the Invention

The object of the invention is to prevent the imbalances and inadequacies in the water lines in the facilities. The system developed for this purpose is designed to minimize the loss of valuable products under all conditions, regardless of external factors such as the water line infrastructure features of the machine. The invention includes a tank, outlet and inlet valves, heater, level sensor, and temperature sensor to feed water at the same flow rate and the same temperature before solid discharge operations.
Another object of the invention is to water supply lines without the need for a pump and provide extra energy savings. In the invention, water supply from the mains line and even 100 It/h flow rate are sufficient according to process requirements and centrifuge product capacities.
Another object of the invention is that it can be configured as an external design valuable phase discharge system. This system can be attached to the centrifuge next to the resting tanks or any type of feeding unit.

Brief Description of the Drawings

Figure 1 : The view of the valuable phase discharge system developed with the invention.
Figure 2a : The integrated view of the internal design valuable phase discharge system developed with the invention into a centrifuge unit that consists of a resting tank, separator, and connections.
Figure 2b : The integrated view of the external design valuable phase discharge system developed with the invention into a centrifuge unit that consists of a resting tank, separator, and connections.
Figure 3a : The view of the interaction of the automatically controlled valuable phase discharge system elements with each other developed with the invention.
Figure 3b : The view of the interaction of the manually controlled valuable phase discharge system elements with each other developed with the invention.

Reference Numerals:

In order to better explain the system developed with this invention, the parts and components in the figures are numbered and the equivalent of each number is given below:

1. Heater
2. Temperature sensor
3. Tank inlet valve
4. Level sensor
5. Tank
6. Tank outlet valve
1. A. Resting tank
2. B. Valuable phase discharge system
3. C. Product inlet connection
4. D. Product outlet connection
5. E. Valuable phase discharge system connection
6. F. Solid Outlet
7. G. Centrifuge
8. H. Control Unit

Detailed Description of the Invention

The present invention relates to a system that ensures that the water fed into the rotating bowl group before the solid discharge operation is at a constant flow rate and a constant temperature so that the valuable phase can be taken out at the maximum level.
This invention ensures that water is fed into the rotating bowl group at the same flow rate and the same temperature each time, regardless of any external factors. External factors can be the water line flow rate of the facility where the machine is installed, the heating system, and other water-using machines in the facility.
This invention is applicable for two control types called automatic and manual. Also, this invention is applicable to two design types called internal and external.
Contents of the automatically controlled valuable phase discharge system (B) have been shown in Figure 1. The invention which is automatically controlled includes a tank (5), a tank outlet valve (6), a heater (1), a tank inlet valve (3), a level sensor (4), and a temperature sensor (2) in order to feed water at the same flow rate and the same temperature before solid discharge operations.
Automatic control is provided by the control unit (H) which might be a programmable logic controller (PLC) or microcontroller. The level sensor (4) with the help of the control unit (H) is also the element used for preventing solid discharge operation in case of low water levels and ensures that the discharge operation is carried out at a constant water flow rate. The heater (1) and temperature sensor (2) ensure that the water to be fed is at the desired temperature in the tank (5), while the tank inlet valve (3) and the level sensor (4) provide the required amount of water in the tank (5) to have the same flow rate.
After the water and electrical connections of the system are made, the tank (5) is filled with water thanks to the tank inlet valve (3). After the water level in the tank (5) exceeds the level sensor (4), the level sensor (4) sends signals to the control unit (H), and the heater (1) starts working and heating the water inside the tank (5) according to signals from the control unit (H). Afterward, the temperature of the water in the tank (5) is measured using the temperature sensor (2). When the temperature of the water in the tank (5) reaches the adjusted value which sets in the control unit (H) according to the process requirements, the control unit (H) sends signals to the heater (1) and the heater (1) stops working. In case the water gets cold due to environmental conditions, the heater (1) is activated again, bringing the temperature of the water to the desired value and continuing this cycle. In this way, the water at a constant temperature in the tank (5) is ready to be fed to the centrifuge (G) before the solid discharge operation.
The tank outlet valve (6) opens automatically to feed the water to the centrifuge (G) before the solid discharge operation. During the feeding period, the tank outlet valve (6) remains open and when the adjusted time sets in the control unit (H) are up, the tank outlet valve (6) is closed automatically.
While water is fed into the centrifuge (G), the water level in the tank (5) decreases and the water starts to fill up to the upper limit of the water level by the tank inlet valve's (3) mechanical working principle. After the feeding of water was completed, the water level would be close to minimum water levels even though the tank inlet valve (3) continued to feed the tank (5). After the supplied water level exceeds the level sensor (4), the level sensor (4) sends signals to the control unit (H) and the heater (1) starts working again and heating the water in the tank (5) according to signals from the control unit (H). The working cycle of the automatically controlled valuable phase discharge system (B) continues in this way no matter whether it's internal or external type.
Contents of the manually controlled valuable phase discharge system (B) have been shown in Figure 1. The invention which has manual control includes a tank (5), a tank outlet valve (6), a heater (1), a level sensor (4), and a tank inlet valve (3) to feed water at the same flow rate and the same temperature before solid discharge operations. In this type of invention, the heater (1) must be selected to be manually adjustable. The heater (1) ensures that the water to be fed is at the desired temperature in the tank (5), while the tank inlet valve (3) provides the required amount of water in the tank (5) to have the same flow rate with the signals from the temperature sensor (2).
After the water and electrical connections of the system, the tank (5) is filled with water thanks to the tank inlet valve (3). After the water level in the tank (5) exceeds the level sensor (4), the level sensor (4) completes the electrical connection of the heater (1), and it starts working and heating the water inside the tank (5). Afterward, when the temperature of the water in the tank (5) reaches the value set in the heater (1) according to process requirements, the heater (1) stops working. In case the water gets cold due to environmental conditions, the heater (1) is activated again, bringing the temperature of the water to the desired value and continuing this cycle. In this way, the water at a constant temperature in the tank (5) is ready to be fed to the centrifuge (G) before the solid discharge operation.
The tank outlet valve (6) opens manually to feed the water to the centrifuge (G) before the solid discharge operation. During the feeding period, the tank outlet valve (6) remains open and when the desired time is up, the tank outlet valve (6) is closed manually.
While water is fed into the centrifuge (G), the water level in the tank (5) decreases and the water starts to fill up to the upper limit of the water level by the tank inlet valve's (3) mechanical working principle. After the feeding of water was completed, the water level would be close to minimum water levels even though the tank inlet valve (3) continued to feed the tank (5). After the supplied water level exceeds the level sensor (4), the level sensor (4) completes the electrical connection of the heater (1) and it starts working and heating the water inside the tank (5). The working cycle of the manually controlled valuable phase discharge system (B) continues in this way no matter whether it's internal or external type.
The invention can be structured as an internal type and an external type. Internal type is structured as integrated into the resting tanks (A) or any type of feeding unit to the centrifuge (G) as shown in Figure 2. External type is added near the resting tanks or (A) any type of feeding unit to the centrifuge (G) as shown in Figure 2. The elements of the internal and external designs valuable phase discharge systems (B) (VPDS) both work with the resting tank (A) where the product is kept before being fed to the centrifuge (G), product inlet connection (C) that used to supply the product to the centrifuge (G), product outlet connection (D) that used to provide the output of the valuable phase that is cleaned by centrifugal force, valuable phase discharge system connection (E) that feeds water into the centrifuge (G) before the solid discharge operation begins, solid outlet (F) that serves as an outlet connection for the solid discharges, centrifuge (G) that used for physically separating the product into phases by exposing it to centrifugal force.
The invention provides extra energy savings with a water supply from the mains to a valuable phase discharge system (B) flow rate of at least 100 It/h without the need for a pump. Water is fed with free flow from the valuable phase discharge system (B) to the centrifuge (G). The height of the tank (5) and flow resistance of the valuable phase discharge system (B) connection (E) affect the flow rate of the supplied water. The flow rate of the fed water is in the range of 0-20 m³/h. The water temperature to be fed is adjusted by the temperature sensor (2) to be generally 1°C higher than the product being processed. This temperature can be 0-150°C according to process requirements. Thanks to the invention, optimum water is obtained independently of the plant water line, minimizing the loss of valuable products.
Before the solid discharge operation, water is fed into the rotating bowl group and the valuable phase in the bowl group is taken out of the machine at the maximum level. Then the solid discharge operation takes place and the product inside the rotating bowl group is thrown out with the help of the solid outlet (F). The rate of valuable phase contained in the waste may vary depending on the centrifugal machine used, the product being processed, and the water flow rate fed from the valuable phase discharge system (B) to the centrifuge (G). The valuable phase volumetric ratio, which is 1 -99% v/v in the product, can be reduced to 1-2% v/v in the waste. In order to reduce the amount of valuable phase in the waste to the aforementioned levels, a facility with optimum water lines is needed. Since this criterion is unfortunately not provided in many plants, valuable phase loss is very high.

Claims

A valuable phase discharge system (B) for centrifuges (G), characterized by comprising:
• Heater (1) that heats the water inside the tank (5) fed by tank inlet valve (3), after the water level in the tank (5) exceeds the level sensor (4),

• Temperature sensor (2) that measures the temperature of the water in the tank (5) and thus maintains it at a constant temperature with the help of the control unit (H) for removing the maximum valuable phase from the system,

• Level sensor (4) that used for preventing solid discharge operation in case of low water levels and that ensures the discharge operation is carried out at a constant water flow rate for removing the maximum valuable phase from the system with the signals from the control unit (H),

• The tank inlet valve (3) that feeds the water from the mains line to the tank (5),

• The tank outlet valve (6) that feeds the water from the valuable phase discharge system (B) to the centrifuge (G) before the solid discharge operation,
A valuable phase discharge system (B) for centrifuges (G) according to claim 1, characterized in that it comprises the level sensor (4) used for preventing solid discharge operation in case of low water levels with the help of a control unit (H) automatically controlled valuable phase discharge system (B).
A valuable phase discharge system (B) for centrifuges (G) according to claim 1, characterized in that it comprises the level sensor (4) used for preventing heaters (1) from working without water with the help of control unit (H) automatically controlled valuable phase discharge system (B).
A valuable phase discharge system (B) for centrifuges (G) according to claim 1, characterized in that it comprises the level sensor (4) used for preventing heaters (1) from working without water in a manually controlled valuable phase discharge system (B).
A valuable phase discharge system (B) for centrifuges (G) according to claim 1, characterized in that it comprises the control unit (H) which can be a programmable logic controller or microcontroller.