阅读说明：本技术 一种聚酯酯化蒸汽余热发电系统 (Polyester esterification steam waste heat power generation system ) 是由 李健 梁龙辉 于 2020-06-23 设计创作，主要内容包括：本发明具体涉及一种聚酯酯化蒸汽余热发电系统,包括酯化蒸汽分离塔、冷却回路、有机朗肯循环发电装置以及凝结水处理系统；所述酯化蒸汽分离塔与聚酯酯化设备的酯化釜连通输出酯化蒸汽；冷却回路与酯化蒸汽分离塔管道连通后,与凝结水处理系统管道连通,输出凝结水至蒸汽分离塔；所述有机朗肯循环发电装置与酯化蒸汽分离塔管道连接后,与凝结水系统管道连通。本发明提供的聚酯酯化蒸汽余热发电系统能够全年运行,提高酯化蒸汽余热的综合利用效率,经济效益。(The invention particularly relates to a polyester esterification steam waste heat power generation system, which comprises an esterification steam separation tower, a cooling loop, an organic Rankine cycle power generation device and a condensed water treatment system; the esterification steam separation tower is communicated with an esterification kettle of the polyester esterification device to output esterification steam; the cooling loop is communicated with a pipeline of the esterification steam separation tower and then communicated with a pipeline of a condensed water treatment system, and condensed water is output to the steam separation tower; and the organic Rankine cycle power generation device is communicated with a condensate system pipeline after being connected with the esterification steam separation tower pipeline. The polyester esterification steam waste heat power generation system provided by the invention can run all the year round, and improves the comprehensive utilization efficiency and economic benefit of the esterification steam waste heat.)

1. The polyester esterification steam waste heat power generation system is characterized in that: the system comprises an esterification steam separation tower (1), a cooling loop, an organic Rankine cycle power generation device and a condensed water treatment system; the esterification steam separation tower (1) is communicated with an esterification kettle of the polyester esterification device to output esterification steam; the inlet of the cooling loop is connected with a gas phase outlet pipeline of the esterification steam separation tower (1), and the outlet of the cooling loop is communicated with a heat source inlet pipeline of a condensed water treatment system; the condensed water treatment system transmits the condensed water at the outlet to a reflux opening of the esterification steam separation tower (1); a heat source inlet of the organic Rankine cycle power generation device is connected with a gas phase outlet pipeline of the esterification steam separation tower (1), and a heat source outlet is communicated with a heat source inlet pipeline of a condensed water system.

2. The polyester esterification steam waste heat power generation system according to claim 1, wherein: the cooling circuit comprises a first steam regulating valve (2) and an air cooler (13); the steam at the gas phase outlet of the esterification steam separation tower (1) enters an air cooler (13) through a first steam regulating valve (2); the heat source outlet of the air cooler (13) is connected with a heat source inlet pipeline of the condensed water treatment system.

3. The polyester esterification steam waste heat power generation system according to claim 1, wherein: the organic Rankine cycle power generation device comprises a second steam regulating valve (3), a preheater (4-1), an evaporator (4-2), a turbine valve (6), a turbine-generator (7), a condenser (8), a working medium pump (9) and the preheater (4-1); the second steam regulating valve (3) is connected with a heat source inlet pipeline of the evaporator (4-2), and a heat source outlet of the evaporator (4-2) is connected with a heat source inlet of the preheater (4-1); a heat source outlet of the preheater (4-1) is connected with a heat source inlet pipeline of the condensed water treatment system;

the working medium outlet of the evaporator is sequentially connected with a turbine valve (6), a turbine-generator (7), a condenser (8), a working medium pump (9), a preheater (4-1) and a working medium inlet of the evaporator in a circulating mode through pipelines;

the organic Rankine cycle power generation device further comprises a turbine bypass valve (5); the turbine bypass valve (5) is connected in parallel with the turbine valve (6) and two ends of the turbine-generator (7); wherein the evaporator (4-2), the preheater (4-1), the turbine valve (6), the turbine-generator (7), the condenser (8), the working medium pump (9), the preheater (4-1) and the turbine bypass valve (5) form a working medium circulation channel; the evaporator (4-2) is connected with the preheater (4-1) through a pipeline to form an esterification steam channel.

4. The polyester esterification steam waste heat power generation system according to claim 1, wherein: the organic Rankine cycle power generation device comprises a third steam regulating valve (3-1), a preheating section evaporator (4-3), a turbine valve (6), a turbine-generator (7), a condenser (8) and a working medium pump (9) which are sequentially connected; also comprises a turbine bypass valve (5); the turbine bypass valve (5) is connected in parallel with the turbine valve (6) and two ends of the turbine-generator (7); wherein the third steam regulating valve (3-1), the preheating section evaporator (4-3), the turbine valve (6), the turbine-generator (7), the condenser (8), the working medium pump (9) and the turbine bypass valve (5) form a working medium circulation channel; and a steam output port of the preheating section evaporator (4-3) outputs the cooled esterification steam.

5. The polyester esterification steam waste heat power generation system according to claim 1, wherein: the condensed water treatment system comprises a condensed water cooler (10), a condensed water storage tank (11) and a reflux pump (12) which are connected in sequence; the input end of the condensed water cooler (10) is connected with the output end pipeline of the cooling loop; the input end of the condensed water cooler (10) is connected with an output end pipeline of the organic Rankine cycle power generation device; the reflux pump (12) sends the generated condensed water to the esterification separation tower.

Technical Field

The invention relates to the technical field of polyester esterification steam waste heat utilization, in particular to a polyester esterification steam waste heat power generation system.

Background

In the polyester synthesis process, esterification steam at about 103 ℃ is generated in the esterification stage, and a large amount of low-grade heat is carried by the part of the esterification steam. Taking a 600t/d polyester production plant as an example, theoretically, the plant would produce about 220t of steam per day and would release about 5.4 x 108 kJ of latent heat (equivalent to 18.4 t standard coal) during liquefaction. In the traditional process, the esterification steam is generally cooled by an air cooler, and a fan of the air cooler consumes a large amount of electric energy, so that the energy waste is huge. In order to improve the utilization efficiency of the waste heat of the esterification steam, part of polyester production enterprises adopt a lithium bromide refrigerating unit to recycle the waste heat of the esterification steam, but the lithium bromide refrigerating unit is only used in summer, and the esterification steam is still cooled by an air cooler in winter and spring and autumn, so that the comprehensive heat energy utilization efficiency of the lithium bromide refrigerating unit is low.

The organic Rankine cycle power generation device can obtain higher vapor pressure under the low temperature condition (80-300 ℃) by utilizing the low boiling point characteristic of organic working media (such as R134a, R245fa and the like), push an expansion machine to work, and drive a generator to generate power, so that the conversion from low-grade heat energy to high-grade electric energy is realized.

Disclosure of Invention

1. The technical problem to be solved is as follows:

in order to solve the technical problems, the invention provides a polyester esterification steam waste heat power generation system, wherein a cooling loop is adopted in the system to cool polyester esterification steam, and an organic Rankine cycle power generation device is adopted to convert low-grade esterification steam heat energy into high-grade electric energy, so that the use of the polyester esterification steam waste heat is utilized all the year around, and the comprehensive utilization efficiency of the heat energy is improved.

2. The technical scheme is as follows:

the polyester esterification steam waste heat power generation system is characterized in that: the system comprises an esterification steam separation tower (1), a cooling loop, an organic Rankine cycle power generation device and a condensed water treatment system; the esterification steam separation tower (1) is communicated with an esterification kettle of the polyester esterification device to output esterification steam; the inlet of the cooling loop is connected with a gas phase outlet pipeline of the esterification steam separation tower, and the outlet of the cooling loop is communicated with a heat source inlet pipeline of a condensed water treatment system; the condensed water treatment system transmits the condensed water at the outlet to a reflux port of the esterification steam separation tower; and a heat source inlet of the organic Rankine cycle power generation device is connected with a gas phase outlet pipeline of the esterification steam separation tower, and a heat source outlet is communicated with a heat source inlet pipeline of a condensed water system.

Further, the cooling circuit includes a first steam regulating valve and an air cooler; steam at a gas phase outlet of the esterification steam separation tower enters an air cooler through a first steam regulating valve; and the heat source outlet of the air cooler is connected with a heat source inlet pipeline of the condensed water treatment system.

Further, the organic Rankine cycle power generation device comprises a second steam regulating valve, a preheater, an evaporator, a turbine valve, a turbine-generator, a condenser, a working medium pump and a preheater; the second steam regulating valve is connected with a heat source inlet pipeline of the evaporator, and a heat source outlet of the evaporator is connected with a heat source inlet of the preheater; and a heat source outlet of the preheater is connected with a heat source inlet pipeline of the condensed water treatment system.

And a working medium outlet of the evaporator is sequentially connected with a turbine valve, a turbine-generator, a condenser, a working medium pump, a preheater and a working medium inlet of the evaporator in a circulating manner through pipelines.

The organic Rankine cycle power generation device further comprises a turbine bypass valve; the turbine bypass valve is connected in parallel with the turbine valve and two ends of the turbine-generator; the evaporator, the preheater, the turbine valve, the turbine-generator, the condenser, the working medium pump, the preheater and the turbine bypass valve form a working medium circulation channel; and the evaporator is connected with the preheater through a pipeline to form an esterification steam channel.

Further, the organic Rankine cycle power generation device comprises a third steam regulating valve, a preheating section evaporator, a turbine valve, a turbine-generator, a condenser and a working medium pump which are sequentially connected; also includes a turbine bypass valve; the turbine bypass valve is connected in parallel with the turbine valve and two ends of the turbine-generator; the third steam regulating valve, the preheating section evaporator, the turbine valve, the turbine-generator, the condenser, the working medium pump and the turbine bypass valve form a working medium circulation channel; and a steam output port of the preheating section evaporator outputs the cooled esterification steam.

Furthermore, the condensed water treatment system comprises a condensed water cooler, a condensed water storage tank and a reflux pump which are connected in sequence; the input end of the condensed water cooler is connected with the output end pipeline of the cooling loop; the input end of the condensed water cooler is connected with an output end pipeline of the organic Rankine cycle power generation device; and the reflux pump conveys the generated condensed water to the esterification separation tower.

3. Has the advantages that:

(1) the polyester esterification steam waste heat power generation system provided by the invention can run all the year round, improves the comprehensive utilization efficiency of the esterification steam waste heat, and has high economic benefit.

(2) In the invention, the esterification steam in the separation tower is divided into two paths, and each path can control the steam flow by a dynamically adjusted steam adjusting valve, so that the polyester production line can stably run under the condition of adjusting flow fluctuation.

(3) The preheater in the organic Rankine cycle power generation device can improve the thermoelectric conversion efficiency of the generator set, further reduce the temperature of the condensed water and effectively reduce the heat load of the condensed water cooler.

(4) The turbine bypass mode in the invention ensures that the organic Rankine cycle power generation device can keep the operation of the organic Rankine cycle under the condition of not outputting power, continuously cools the esterification steam, and further ensures the stable operation of the polyester production line.

Drawings

FIG. 1 is a connection diagram of a first embodiment of the present invention;

fig. 2 is a connection diagram of a second embodiment of the present invention.

Detailed Description

A polyester esterification steam waste heat power generation system comprises an esterification steam separation tower 1, a cooling loop, an organic Rankine cycle power generation device and a condensed water treatment system; the esterification steam separation tower 1 is communicated with an esterification kettle of the polyester esterification device to output esterification steam; the inlet of the cooling loop is connected with a gas phase outlet pipeline of the esterification steam separation tower 1, and the outlet of the cooling loop is communicated with a heat source inlet pipeline of a condensed water treatment system; the condensed water treatment system transmits the condensed water at the outlet to a reflux port of the esterification steam separation tower 1; and a heat source inlet of the organic Rankine cycle power generation device is connected with a gas phase outlet pipeline of the esterification steam separation tower 1, and a heat source outlet is communicated with a heat source inlet pipeline of a condensed water system.

Further, the cooling circuit comprises a first steam regulating valve 2 and an air cooler 13; the steam at the gas phase outlet of the esterification steam separation tower 1 enters an air cooler 13 through a first steam regulating valve 2; the heat source outlet of the air cooler 13 is connected with a heat source inlet pipeline of the condensed water treatment system.

Further, the organic Rankine cycle power generation device comprises a second steam regulating valve 3, a preheater 4-1, an evaporator 4-2, a turbine valve 6, a turbine-generator 7, a condenser 8, a working medium pump 9 and a preheater 4-1; the second steam regulating valve 3 is connected with a heat source inlet pipeline of the evaporator 4-2, and a heat source outlet of the evaporator 4-2 is connected with a heat source inlet of the preheater 4-1; the heat source outlet of the preheater 4-1 is connected with a heat source inlet pipeline of a condensed water treatment system.

And a working medium outlet of the evaporator is sequentially connected with a turbine valve 6, a turbine-generator 7, a condenser 8, a working medium pump 9, a preheater 4-1 and a working medium inlet of the evaporator in a circulating manner through pipelines.

The organic Rankine cycle power generation device further comprises a turbine bypass valve 5; the turbine bypass valve 5 is connected in parallel with the turbine valve 6 and two ends of the turbine-generator 7; the evaporator 4-2, the preheater 4-1, the turbine valve 6, the turbine-generator 7, the condenser 8, the working medium pump 9, the preheater 4-1 and the turbine bypass valve 5 form a working medium circulation channel; and the evaporator 4-2 is connected with the preheater 4-1 through a pipeline to form an esterification steam channel.

Further, the organic Rankine cycle power generation device comprises a third steam regulating valve 3-1, a preheating section evaporator 4-3, a turbine valve 6, a turbine-generator 7, a condenser 8 and a working medium pump 9 which are sequentially connected; also includes a turbine bypass valve 5; the turbine bypass valve 5 is connected in parallel with the turbine valve 6 and two ends of the turbine-generator 7; wherein the third steam regulating valve 3-1, the preheating section evaporator 4-3, the turbine valve 6, the turbine-generator 7, the condenser 8, the working medium pump 9 and the turbine bypass valve 5 form a working medium circulation channel; and a steam output port of the preheating section evaporator 4-3 outputs the cooled esterification steam.

Further, the condensed water treatment system comprises a condensed water cooler 10, a condensed water storage tank 11 and a reflux pump 12 which are connected in sequence; the input end of the condensed water cooler 10 is connected with the output end pipeline of the cooling loop; the input end of the condensed water cooler 10 is connected with an output end pipeline of the organic Rankine cycle power generation device; the reflux pump 12 sends the produced condensed water to the esterification separation column.