KR102193647B1 - Urea supply unit for exhaust gas cleaning system - Google Patents

Abstract

A reductant supply unit for an exhaust gas treatment device according to the present invention may comprise: a base in which a junction box is installed such that a cable may be connected from the outside; a motor pump installed over the base; a supply-side block unit which is fixated to the base, and to which a plurality of elements are attached so as to supply urea from a tank to the motor pump; a throttle check valve connected to the motor pump, and constructed to prevent the backflow of the urea pressurized by the motor pump and to set a flow rate; an outlet connecting unit installed at the base, and formed to send the urea discharged from the throttle check valve to a dosing unit; and a collection-side block unit which is installed at the base, and to which a plurality of elements are attached so as to partially collect the urea discharged from the throttle check valve to the tank. Therefore, space utilization can be improved.

Description

Reductant supply unit for exhaust gas treatment system {UREA SUPPLY UNIT FOR EXHAUST GAS CLEANING SYSTEM}

The present invention relates to a reducing agent supply unit for an exhaust gas treatment apparatus.

The regulations on exhaust gas of ships are recently being expanded by international organizations such as IMO and governments of each country, and technical measures are being prepared for this. The exhaust gas emissions of ships that cause pollution include nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), PM, methane (CH ₄ ), and soot. Among these, nitrogen oxide treatment is a selective non-catalytic reduction (SNCR) method in which ammonia or ammonia water is injected into high-temperature exhaust gas in the temperature range of 870 ~ 1200 ℃ without a catalyst, and an exhaust gas recycling method that reduces nitrogen oxides by lowering the combustion temperature. Several methods have been proposed including (Exhaust Gas Recirculation; EGR), and the Selective Catalytic Reduction (SCR) system with proven performance, safety and economics is in the spotlight.

In order to install an exhaust gas treatment device such as SCR for treating nitrogen oxides on a ship, a problem is how to install it in a narrow space inside the ship. Unlike automobiles, if you have a large engine or multiple engines such as a ship or a plant, the exhaust gas emission also increases so that the size of the exhaust treatment system increases accordingly, and how to configure the treatment of gas emitted from multiple engines in terms of equipment. Whether or not it affects the efficiency.

SCR is classified into HC-SCR using hydrocarbon, H ₂ -SCR using hydrogen and NH ₃ -SCR using ammonia depending on the reducing agent used in the reaction. Among them, NH ₃ -SCR is divided into a method using anhydrous ammonia as it is and a method using urea (urea water). In the case of urea SCR, it has a system for supplying urea to the catalytic reactor. Since such a reducing agent supply and dosing system may vary depending on the amount and temperature of exhaust gas and the concentration of nitrogen oxides (NOx), it has complex equipment and piping elements for automated control and monitoring and prevention of clogging caused by urea coagulation. It becomes difficult to install and maintain.

*Related prior art

Korean Patent Application Publication No. 10-2018-0075039 (published on July 4, 2018)

An object of the present invention is to provide a reducing agent supply unit for an exhaust gas treatment apparatus capable of improving space utilization by utilizing a block and shortening a piping line to improve urea supply response speed and facilitate maintenance or repair.

A reducing agent supply unit for an exhaust gas treatment apparatus according to the present invention includes: a base on which a junction box is installed to which cables are connected from the outside; A motor pump installed on the base; A supply-side block portion fixed to the base and having a plurality of elements attached thereto to supply urea from the tank to the motor pump; A throttle check valve connected to the motor pump, formed to prevent reverse flow of urea pressurized by the motor pump, and configured to set a flow rate; An outlet connection part installed on the base and formed to send urea from the throttle check valve to a dosing unit; And a recovery-side block portion provided on the base and having a plurality of elements attached thereto to partially recover urea from the throttle check valve to the tank.

As an example related to the present invention, the base includes: an upper tray having a lifting ring provided at an edge thereof and having a drain plug formed at a lower side thereof; And a plurality of beam members attached to a lower edge of the upper tray to support the upper tray.

As an example related to the present invention, the motor pump includes a first motor pump and a second motor pump installed in parallel to the base, and the supply-side block part corresponds to the first motor pump and the second motor pump. It may include a first supply-side block portion and a second supply-side block portion respectively connected.

As an example related to the present invention, the supply-side block unit includes: a first block body having a first flow path therein to allow urea to flow; A plurality of valves formed to be disposed on the first flow path by being fastened to the first block body and opening and closing urea; And at least one pressure sensing unit formed to be disposed on the first passage by being fastened to the first block body, and configured to sense a pressure of urea.

As an example related to the present invention, the supply side block unit further includes a filter configured to be disposed on the first flow path by being fastened to the first block body, and configured to filter foreign substances contained in urea. I can.

As an example related to the present invention, the plurality of valves may include: a first ball valve attached to a side surface of the first block body to open and close the inflow of urea into the block body; And a second ball valve attached to the front surface of the first block body to open and close a flow rate transmitted to the motor pump of urea.

As an example related to the present invention, the pressure sensing unit may include a first pressure sensor that senses a pressure of urea from the filter unit and transmits an electrical signal.

As an example related to the present invention, the reducing agent supply unit for the exhaust gas treatment device further includes a second pressure sensor for transmitting an electrical signal by sensing a difference in pressure between both ends of the motor pump, and the supply side block unit It may include a shut-off valve attached to the lower surface of the first block body to connect or block a flow path to the second pressure sensor.

As an example related to the present invention, the recovery-side block unit includes: a second block body having a second flow path therein to allow urea to flow; A pair of throttle valves coupled to the second block body and formed to be disposed on the second flow path, and configured to pass a predetermined flow rate; And a third pressure sensor formed to be disposed on the second passage by being fastened to the second block body, and configured to sense a pressure of urea and transmit an electrical signal.

As an example related to the present invention, the pair of throttle valves may include a first throttle valve and a second throttle valve arranged in parallel on the second flow path so that they are always open by a preset opening degree.

As an example related to the present invention, the reducing agent supply unit for the exhaust gas treatment apparatus may further include a pressure gauge configured to directly recognize the pressure of urea exiting the motor pump.

As an example related to the present invention, the reducing agent supply unit for the exhaust gas treatment device further comprises a temperature sensor installed in the second block body and transmitting an electrical signal by sensing the temperature of urea exiting the motor pump. I can.

According to the reducing agent supply unit for an exhaust gas treatment apparatus according to the present invention, a supply-side block portion and a recovery-side block portion, etc. are installed in a state in which a motor pump and a throttle check valve are installed on the base, and are made of a module body using blocks. Space utilization is improved, and piping lines to connect can be omitted. Therefore, it is possible to improve the response speed of urea water discharge and to minimize the set delay in supply of urea water. As a manager, you can get convenience in maintenance, replacement and management by omitting the piping line.

As an example related to the present invention, a pair of throttle valves are installed on the recovery side block in order to recover urea to the tank, compared to the case where the safety valve and the throttle valve are installed at the same time. It can solve the problem of not being able to operate normally against overpressure.

1 is a schematic front view of a reducing agent supply unit 100 for an exhaust gas treatment apparatus according to the present invention.
2 is a schematic plan view of the reducing agent supply unit 100 for the exhaust gas treatment apparatus of FIG. 1.
3 is a schematic side view of the reducing agent supply unit 100 for the exhaust gas treatment apparatus of FIG. 1.
4 is a circuit diagram of a reducing agent supply unit for an exhaust gas treatment apparatus according to the present invention.

Hereinafter, a reducing agent supply unit for an exhaust gas treatment apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

In the supply unit related to the present invention, in a selective catalytic reduction exhaust gas treatment device for treating nitrogen oxides, the reducing agent is sent to a dosing unit at a certain pressure or recovered to a tank to stably supply the reducing agent. The reducing agent may be in a liquid state such as urea.

1 to 4, the reducing agent supply unit 100 for an exhaust gas treatment apparatus according to the present invention has a form in which various elements are mounted on a base 110. The base 110 is composed of an upper tray 111 and a plurality of beam members 113 supporting the upper tray 111. A lifting ring 112 is provided at the edge of the upper tray 111, and a drain plug 115 (see FIG. 3) is provided at one side of the lower end. The supply unit 100 installed on the base 110 has a modularization and blockage of parts, so its occupied volume is small and has convenience in terms of movement and installation. One side of the base 110 is provided with a junction box 101 for connecting power and signal cables from the outside.

Motor pumps 121 and 122 for pressurizing urea to 5 ~ 7 bar are installed on the base 110. The motor pump may have a first motor pump 121 and a second motor pump 122 arranged in parallel so that the other can be used when there is a failure or a maintenance stop while using one of them.

In front of the motor pumps 121 and 122, supply side block portions 130 and 140 to which a plurality of elements are attached to supply urea from the tank to the motor pumps 121 and 122 are installed. Referring to FIGS. 2 and 3 together, the supply-side block portions 130 and 140 correspond to the first motor pump 121 and the second motor pump 122, and the first supply-side block portion 130 and the second supply-side block. It is made of part 140. The first supply-side block unit 130 and the second supply-side block unit 140 are provided with first block bodies 131 and 141 in which a first flow path is formed so that urea can flow. The first block bodies 131 and 141 form a flow path through processing such as drilling on a metal block, and attach various elements such as valves or filters to the inside or surface of the block to form a hydraulic circuit. Specifically, a plurality of valves for opening and closing urea and at least one pressure sensing unit formed to sense a pressure of urea may be mounted on the first block bodies 131 and 141. In addition, filters 133 and 143 are mounted in front of the first block bodies 131 and 141 so as to be fastened to the first block bodies 131 and 141 to be disposed on the first flow path. These filters 133 and 143 are configured to filter out foreign substances contained in urea before being sent to the motor pumps 121 and 122.

A plurality of valves installed on the first block body (131, 141) are installed on the side of the first ball valve (135) to open and close the inflow to the first block body (131, 141), and a motor of urea installed on the front side. It may have second ball valves 136 and 146 that open and close the flow rate delivered to the pumps 121 and 122. As shown in FIG. 2, a first pressure sensor 149 for transmitting an electrical signal by sensing pressure of urea exiting the filters 133 and 143 may be attached to the side of the first block body 141. The first pressure sensor 149 may be installed together with a third ball valve 148 for discharging air in the pipeline.

A second pressure sensor 178 may be installed to detect a difference in pressure at both ends of the filters 133 and 143 and transmit an electrical signal so that appropriate measures may be taken according to the performance state of the filters 133 and 143. To this end, the supply-side block portions 130 and 140 are attached to the lower surfaces of the first block bodies 131 and 141 and are provided with shut-off valves 137 and 147 for connecting or blocking the flow path to the second pressure sensor 178 Can be. If the measured values of the first pressure sensor 149 and the third pressure sensor 175 to be described later are used to detect the differential pressure, the second pressure sensor 178 and the shut-off valves 137 and 147 may be omitted. .

The urea introduced through the inlet unit 150 in this way is the motor pumps 121 and 122 through the supply-side block units 130 and 140 in which various valves, filters 133 and 143 and sensors are intensively arranged through the block. The length of the flow path can be shortened while being supplied to the channel, and the responsiveness of fluid control can be improved accordingly, and space can be saved compared to the case where elements are individually attached and installed through piping, simplifying manufacturing and reducing cost. Also contributes to.

2, throttle check valves 125 and 126 configured to prevent reverse flow of urea pressurized by the motor pumps 121 and 122 and set the flow rate are disposed at the rear ends of the motor pumps 121 and 122 . At the rear end of the throttle check valves 125 and 126, an outlet connection 160 formed to send urea to the dosing unit, and a recovery side block 170 with a plurality of elements attached to partially recover urea to the tank. ) Is installed. The recovery-side block unit 170 also includes a second block body 171 having a second flow passage therein for intensive installation, and various hydraulic elements are mounted on the second block body 171. These are coupled to the second block body 171 and formed to be disposed on the second flow path, and a pair of throttle valves 173 and 174 formed to pass a predetermined flow rate, and the second block body 171 It may include a third pressure sensor 175 formed to be disposed on the second flow path by being fastened to and configured to transmit an electrical signal by sensing the pressure of urea. In addition, a temperature sensor 176 that senses the temperature of urea and transmits an electrical signal may be mounted on the recovery-side block unit 170.

A pair of throttle valves 173 and 174 included in the recovery-side block unit 170 are a first throttle valve 173 and a second throttle valve arranged in parallel on the second flow path so that they are always open by a preset opening degree. 174). Part of the urea pressurized through the motor pumps 121 and 122 is sent to the dosing unit, while the remaining flow rate is returned to the tank via the throttle valves 173 and 174. Since these throttle valves 173 and 174 are always open as much as a preset opening degree, even if one of the throttle valves 173 and 174 has a problem when a pressure higher than the reference value occurs in the flow path, the other is in an open state. Part of the is sent to the tank through the open throttle valve (173, 174). As a result, pressure leakage or explosion can be prevented, cost can be reduced compared to using an expensive safety valve, and the system can be stably maintained.

A pressure gauge 190 may be installed at the rear end of the motor pumps 121 and 122 so that the pressure of urea exiting the pump can be directly recognized at the site.

The configuration and method of the described embodiments are not limited to the reducing agent supply unit for the exhaust gas treatment apparatus described above. The above embodiments may be configured by selectively combining all or part of each of the embodiments so that various modifications can be made.

100: reducing agent supply unit for exhaust gas treatment device
101: junction box 110: base
111: upper tray 112: lifting hook
113: beam member 121: first motor pump
122: second motor pump 125: first throttle check valve
126: second throttle check valve 130: first supply side block portion
131, 141: first block body 133, 143: filter
135: first ball valve 136, 146: second ball valve
137, 147: shut-off valve 140: second supply side block portion
148, 175: third ball valve 149: first pressure sensor
170: recovery side block unit 171: second block body
172: first throttle valve 173: second throttle valve
174: fourth ball valve 175: third pressure sensor
176: temperature sensor 178: second pressure sensor
190: pressure gauge

Claims (12)

A base on which a junction box for connecting cables from the outside is installed;
A motor pump installed on the base;
A supply-side block portion fixed to the base and having a plurality of elements attached thereto to supply urea from the tank to the motor pump;
A throttle check valve connected to the motor pump, formed to prevent reverse flow of urea pressurized by the motor pump, and configured to set a flow rate;
An outlet connection part installed on the base and formed to send urea from the throttle check valve to a dosing unit; And
A reducing agent supply unit for an exhaust gas treatment apparatus, which is installed on the base and includes a recovery-side block portion to which a plurality of elements are attached to partially recover the urea from the throttle check valve to the tank.
The method of claim 1,
The base,
An upper tray provided with a lifting ring at the edge and a drain plug formed at a lower side thereof; And
A reducing agent supply unit for an exhaust gas treatment apparatus comprising a plurality of beam members attached to a lower edge of the upper tray to support the upper tray.
The method of claim 1,
The motor pump includes a first motor pump and a second motor pump installed in parallel to the base,
The supply-side block portion includes a first supply-side block portion and a second supply-side block portion respectively connected to correspond to the first motor pump and the second motor pump, and a reducing agent supply unit for an exhaust gas treatment apparatus.
The method of claim 1,
The supply side block portion,
A first block body having a first flow path formed therein to allow urea to flow;
A plurality of valves formed to be disposed on the first flow path by being fastened to the first block body and opening and closing urea; And
A reducing agent supply unit for an exhaust gas treatment apparatus comprising at least one pressure sensing unit formed to be disposed on the first flow path by being fastened to the first block body, and configured to sense a pressure of urea.
The method of claim 4,
A reducing agent supply unit for an exhaust gas treatment apparatus, further comprising a filter formed to be disposed on the first flow path by being fastened to the first block body, and configured to filter foreign substances contained in urea.
The method of claim 5,
The plurality of valves,
A first ball valve attached to a side surface of the first block body to open and close the inflow of urea into the first block body; And
A reducing agent supply unit for an exhaust gas treatment apparatus comprising a second ball valve attached to a front surface of the first block body to open and close a flow rate transmitted to the motor pump of urea.
The method of claim 6,
The pressure sensing unit,
A reducing agent supply unit for an exhaust gas treatment apparatus comprising a first pressure sensor for transmitting an electrical signal by sensing the pressure of urea exiting the filter.
The method of claim 7,
Further comprising a second pressure sensor for transmitting an electrical signal by detecting a difference in pressure at both ends of the motor pump,
The supply-side block portion is attached to a lower surface of the first block body and comprises a shut-off valve for connecting or blocking a flow path to the second pressure sensor.
The method of claim 1,
The recovery-side block portion,
A second block body having a second flow path formed therein to allow urea to flow;
A pair of throttle valves coupled to the second block body and formed to be disposed on the second flow path, and configured to pass a predetermined flow rate; And
A reducing agent supply unit for an exhaust gas treatment apparatus including a third pressure sensor formed to be disposed on the second flow path by being fastened to the second block body and configured to transmit an electrical signal by sensing the pressure of urea. .
The method of claim 9,
The pair of throttle valves,
A reducing agent supply unit for an exhaust gas treatment apparatus comprising a first throttle valve and a second throttle valve arranged in parallel on the second passage so as to be always open by a predetermined opening degree.
The method of claim 9,
A reducing agent supply unit for an exhaust gas treatment apparatus further comprising a pressure gauge formed to directly recognize the pressure of urea exiting the motor pump.
The method of claim 9,
A reducing agent supply unit for an exhaust gas treatment apparatus, which is installed on the second block body and further comprises a temperature sensor for sensing a temperature of urea exiting the motor pump and transmitting an electrical signal.

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