CN-116839406-B - System for heating raw water by using waste heat of dry slag machine of coal-fired boiler

CN116839406BCN 116839406 BCN116839406 BCN 116839406BCN-116839406-B

Abstract

The application provides a system for heating raw water by utilizing waste heat of a slag drier of a coal-fired boiler, which comprises a raw water heat exchanger component, an upper wall heat exchanger component and a lower wall heat exchanger component, wherein the raw water heat exchanger component is connected right above a conveying component of an inclined section of the slag drier by hanging welding through a connecting rod, the upper wall heat exchanger component is arranged on the upper inner surface of a shell of the slag drier by wall bonding welding, the lower wall heat exchanger component is arranged on the lower inner surface of the shell of the slag drier by wall bonding welding, the upper ends of the upper wall heat exchanger component and the lower wall heat exchanger component are communicated to the upper end of the raw water heat exchanger component through pipelines, and the raw water heating system provided by the application utilizes the flow of raw water in the heat exchanger to absorb the waste heat of slag, realizes the recycling of the waste heat of slag, simultaneously plays a role of cooling and cooling for slag and slag drier equipment, and can reduce the inlet of cooling air.

Inventors

ZHANG LIJUN
CUI MIN
LI JIQIANG
LIU YONGQIANG
JIA YUNPENG
Xu Xiangri
Ding Guangzheng

Assignees

大唐临清热电有限公司

Dates

Publication Date: 20260508
Application Date: 20230524

Claims (6)

1. The system for heating raw water by utilizing waste heat of the dry slag machine of the coal-fired boiler comprises a boiler (1), the dry slag machine (2), a conveying component (3) and a cleaning component (4), wherein the dry slag machine (2) comprises a horizontal section and an inclined section, the horizontal section is arranged right below a slag well of the boiler (1), the conveying component (3) is arranged in the dry slag machine (2), the cleaning component (4) is arranged below the conveying component (3), Comprises an air inlet electric air door (5), a raw water heat exchanger component (8), an upper wall heat exchanger component (9), a lower wall heat exchanger component (10), a raw water tank (12), a raw water feed pump (13) and a raw water feed pipe (14); The raw water heat exchanger component (8) is fixedly connected to the right upper part of the conveying component (3) of the inclined section of the slag drier (2) in a suspending way through a connecting rod, the upper wall heat exchanger component (9) is fixedly arranged on the upper inner surface of the shell of the slag drier (2) in an adherence way, the lower wall heat exchanger component (10) is fixedly arranged on the lower inner surface of the shell of the slag drier (2) in an adherence way, and the upper ends of the upper wall heat exchanger component (9) and the lower wall heat exchanger component (10) are communicated to the upper end of the raw water heat exchanger component (8) through pipelines; The raw water tank (12) is internally provided with the raw water feed pump (13), an outlet main pipe of the raw water feed pump (13) is connected with the raw water feed pipe (14), and the raw water feed pipe (14) is split into two paths which are respectively connected with the upper wall heat exchanger assembly (9) and the lower wall heat exchanger assembly (10); The raw water heat exchanger assembly (8) comprises a first upper header (81), a first lower header (82), and a first heat exchanger water pipe (83) connected between the first upper header (81) and the first lower header (82); The upper wall heat exchanger assembly (9) comprises a second upper header (91), a second lower header (92) and a second heat exchanger water pipe (93) connected between the second upper header (91) and the second lower header (92), the lower wall heat exchanger assembly (10) comprises a third upper header (101), a third lower header (102) and a third heat exchanger water pipe (103) connected between the third upper header (101) and the third lower header (102), two paths of water flows of the raw water feed pipe (14) are respectively connected to the second lower header (92) of the upper wall heat exchanger assembly (9) and the third lower header (102) of the lower wall heat exchanger assembly (10); The first lower header (82) of the raw water heat exchanger assembly (8) is connected with a raw water outlet pipeline (15) for outflow of the raw water after heat exchange; The second upper header (91) of the upper wall heat exchanger assembly (9) and the third upper header (101) of the lower wall heat exchanger assembly (10) are both connected to the first upper header (81) of the raw water heat exchanger assembly (8) by a pipe.
2. A system for heating raw water by using waste heat of a dry slag machine of a coal-fired boiler as claimed in claim 1, wherein a pressure gauge, a thermometer and a flowmeter are arranged on the raw water outlet pipeline (15).
3. A system for heating raw water by using waste heat of a dry slag machine of a coal-fired boiler as claimed in claim 1, wherein a heat exchanger soot blower (11) extending to the inner side of the dry slag machine (2) is arranged on the upper shell of the dry slag machine, and the heat exchanger soot blower (11) is controlled to start soot blowing by a timing soot blowing control unit.
4. The system for heating raw water by using waste heat of dry slag machine of coal-fired boiler as claimed in claim 1, wherein a pressure gauge, a thermometer and a flowmeter are arranged on the main pipe at the outlet of the raw water feed pump (13).
5. The system for heating raw water by using waste heat of a dry slag machine of a coal-fired boiler as claimed in claim 1, wherein an outlet of the raw water feed pump (13) is provided with a check valve (131).
6. The system for heating raw water by utilizing waste heat of dry slag machine of coal-fired boiler as claimed in claim 1, further comprising a slag crusher (6) and a slag bin (7), wherein the slag crusher (6) is arranged right below the furthest end transported by the conveying assembly (3), and the slag bin (7) is arranged below the slag crusher (6) and is used for containing crushed slag.

Description

System for heating raw water by using waste heat of dry slag machine of coal-fired boiler Technical Field The application relates to the technical field of waste heat recovery and utilization of a dry slag machine of a coal-fired boiler, in particular to a system for heating raw water by using waste heat of the dry slag machine of the coal-fired boiler. Technical Field When the coal-fired boiler of the power station runs, high-temperature slag is generated, the high-temperature slag needs to be conveyed to a slag bin outside a boiler room, and in the work of conveying the high-temperature slag, a slag drier is core equipment for conveying the slag. The high-temperature slag is conveyed out through the conveying chain of the slag drier, meanwhile, under the action of negative pressure of the boiler, ambient cold air reversely enters the slag drier to perform sufficient heat exchange with the high-temperature slag, so that the slag is gradually cooled on the conveying belt, and the cold air entering from the side surface also has a cooling effect on the shell of the slag drier, the carrier roller of the conveying belt and the conveying chain. The air can be introduced into the furnace to cool the slag of the equipment, and the cold air can be introduced into the furnace to participate in combustion after absorbing the radiant heat of the boiler and the heat of the slag. Although the cooling air can recycle part of the heat of the slag, the temperature of the slag falling after the boiler burns is about 700-900 ℃, the cooling air can recycle only a small amount of heat, and a large part of heat is not recycled to cause waste. And the part of cooling air entering from the slag drier is air leakage at the bottom of a disordered hearth, if the air quantity is too large, the combustion working condition in the hearth can be disturbed after the cooling air enters the hearth, so that the central position of flame is lifted, the consumption of reheat and temperature reduction water is increased, the exhaust gas temperature is increased, and the mechanical incomplete combustion heat loss and the exhaust gas heat loss of a boiler are increased, thereby affecting the safety and economic operation of boiler equipment. Therefore, the recovery of the waste heat of the high-temperature slag and the reduction of energy waste are the problems to be solved urgently at present, and the development of a device capable of recovering the waste heat of the slag drier and reducing the using amount of cooling air of the slag drier is imperative. Disclosure of Invention The application provides a system for heating raw water by using waste heat of a dry slag machine of a coal-fired boiler, wherein the waste heat of slag and the dry slag machine is used for heating raw water in a mode of installing a heat exchanger in the dry slag machine, In order to achieve the technical effects, the application provides a system for heating raw water by utilizing waste heat of a dry slag machine of a coal-fired boiler, which comprises a boiler, the dry slag machine, a conveying component and a cleaning component, wherein the dry slag machine comprises a horizontal section and an inclined section, the horizontal section is arranged right below a slag well of the boiler, the conveying component is arranged in the dry slag machine, and the cleaning component is arranged below the conveying component; The device also comprises an air inlet electric air door, a raw water heat exchanger component, an upper wall heat exchanger component, a lower wall heat exchanger component, a raw water tank, a raw water feed pump and a raw water feed pipe; The raw water heat exchanger component is suspended and fixedly connected right above the conveying component of the slag drier inclined section through a connecting rod, the upper wall heat exchanger component is fixedly arranged on the upper inner surface of the slag drier shell in an adherence manner, and the lower wall heat exchanger component is fixedly arranged on the lower inner surface of the slag drier shell in an adherence manner; The raw water tank is internally provided with the raw water feed pump, an outlet main pipe of the raw water feed pump is connected with the raw water feed pipe, and the raw water feed pipe is split into two paths which are respectively connected with the upper wall heat exchanger component and the lower wall heat exchanger component. As a preferred embodiment, the raw water heat exchanger assembly includes a first upper header, a first lower header, and the first heat exchanger water tube connected between the first upper header and the first lower header. As a preferred embodiment, the upper wall heat exchanger assembly comprises a second upper header, a second lower header and the second heat exchanger water pipe connected between the second upper header and the second lower header, the lower wall heat exchanger assembly comprises a third upper header, a third lower header and th