阅读说明：本技术 多效蒸发节能设备 (Multi-effect evaporation energy-saving equipment ) 是由 魏传涛 宗仁邦 季鹏飞 肖爱英 王从民 于 2019-11-14 设计创作，主要内容包括：本发明的多效蒸发节能设备,其特征在于：沿物料走向设置依次连接的进料缓存罐、乏汽换热器、加热器、蒸发器、冷凝器；蒸发器的物料蒸汽出口经三通管连接乏汽换热器的热介质入口和冷凝器的待冷凝物料入口,乏汽换热器的热介质出口连接冷凝器的另一个物料入口,使物料蒸发形成的一部分蒸汽作为乏汽换热器的热介质从而为另一部分物料进行第一次预热。本发明的有益效果是,利用余热换热工艺,对物料进行预热,同时降低了排出系统外物料的温度,提高了热能效率,降低了热能的消耗,降低新鲜蒸汽的耗量,降低了物料的处理成本,为用户节省了生产成本。(The invention discloses a multi-effect evaporation energy-saving device, which is characterized in that: a feeding cache tank, a waste steam heat exchanger, a heater, an evaporator and a condenser which are connected in sequence are arranged along the direction of the materials; the material steam outlet of the evaporator is connected with the heat medium inlet of the waste steam heat exchanger and the material inlet to be condensed of the condenser through a three-way pipe, the heat medium outlet of the waste steam heat exchanger is connected with the other material inlet of the condenser, and part of steam formed by evaporation of the material is used as the heat medium of the waste steam heat exchanger so as to preheat the other part of material for the first time. The invention has the advantages that the waste heat exchange process is utilized to preheat the material, the temperature of the material discharged out of the system is reduced, the heat energy efficiency is improved, the heat energy consumption is reduced, the consumption of fresh steam is reduced, the material treatment cost is reduced, and the production cost is saved for users.)

1. A multi-effect evaporation energy-saving equipment is characterized in that:

a feeding cache tank, a waste steam heat exchanger, a heater, an evaporator and a condenser which are connected in sequence are arranged along the direction of the materials; the material inlet of the waste steam heat exchanger is connected with the material outlet of the feeding cache tank, and the material outlet of the waste steam heat exchanger can be connected with the material inlet of the heater;

the secondary steam outlet of the evaporator is connected with the heat medium inlet of the waste steam heat exchanger and the steam inlet to be condensed of the condenser through a three-way pipe, the heat medium condensate outlet of the waste steam heat exchanger is connected with the other material inlet of the condenser, and a part of steam formed by evaporating the materials is used as the heat medium of the waste steam heat exchanger so as to carry out primary preheating on the materials entering the evaporator.

2. The multi-effect evaporation energy saving device of claim 1, characterized in that: the multi-effect evaporation energy-saving equipment is also provided with a condensate water preheater, wherein a material inlet of the condensate water preheater is connected with a material outlet of the exhaust steam heat exchanger, and a material outlet of the condensate water preheater is connected with a material inlet of the heater; the hot medium inlet of the condensed water preheater is connected with the condensed water outlet of the heater, and the hot medium outlet of the condensed water preheater is connected with the condensed water discharge pipe, so that the condensed water formed by hot medium steam of the heater is used as the hot medium of the condensed water preheater to carry out secondary preheating on the material.

3. The multi-effect evaporation energy saving device according to claim 2, characterized in that: the condensed water outlet of the heater is connected with the hot medium inlet of the condensed water preheater through the condensed water collecting tank.

4. The multi-effect evaporation economizer of claim 1, 2 or 3 wherein: the heaters correspond to the evaporators one by one, the heaters adopt single-effect heaters, and the evaporators adopt single-effect evaporators, or the heaters adopt multi-effect heaters, and the evaporators adopt multi-effect evaporators.

5. The multi-effect evaporation energy saving device of claim 4, characterized in that: when a multi-effect evaporator is adopted, a heat medium inlet of the exhaust steam heat exchanger is connected with a material steam outlet of the last-effect evaporator; the hot medium inlet of the condensed water preheater is connected with the condensed water outlet of the heater in front of the one-effect evaporator.

6. The multi-effect evaporation energy saving device of claim 4, characterized in that: the bottom of the last effect evaporator is connected with the thickener through a slurry pump, the outlet at the bottom of the thickener is connected with a slurry centrifugal dehydrator, the discharge port of the slurry centrifugal dehydrator is connected with a dryer through a conveyer belt, the water outlet of the slurry centrifugal dehydrator is connected with a mother liquor tank, and the overflow port of the supernatant at the top of the thickener is also connected with the mother liquor tank; after settling and centrifugal separation, the slurry is sent to a dryer by a conveyer belt for drying.

7. The multi-effect evaporation economizer of claim 1, 2 or 3 wherein: a medium inlet of the condenser is connected with a circulating cooling water inlet pipe, a medium outlet is connected with a circulating cooling water return pipe, a condensed material outlet is connected with a feed inlet of the plate heat exchanger through a vacuum pump, and a discharge port of the plate heat exchanger is connected with a sewage discharge pipe; a medium inlet of the plate heat exchanger is connected with a circulating cooling water inlet pipe, and a medium outlet of the plate heat exchanger is connected with a circulating cooling water return pipe.

Technical Field

The invention relates to the technical field of multi-effect evaporation equipment and processes, in particular to multi-effect evaporation energy-saving equipment.

Background

The single-effect or multi-effect evaporator is a process equipment with wider application. It can make the solution concentration of the solution and other materials be raised by evaporating partial water, and the solute-containing solution can be raised because of its concentration. The method has the advantages of high speed, high efficiency, few working procedures and labor saving, and can meet the requirements of various chemical processes. Has wide prospect in chemical industry, light industry, building material, food, forest chemical industry, medicine, biochemistry and other industries. At present, multiple-effect evaporation is applied to the wastewater treatment process, and a multiple-effect evaporation device is required to be applied to most of chemical plant production. Because the waste water feeding temperature is very low, the waste water material with lower temperature is evaporated, a certain amount of heat needs to be absorbed in the evaporation process, so that the material temperature is raised to the boiling point temperature, generally, fresh steam provides heat, and the steam consumption is very large. Therefore, the multi-effect evaporation device has higher energy consumption in operation.

Disclosure of Invention

In order to make up for the defects of the prior art, the invention provides the multi-effect evaporation energy-saving equipment which is simple in structure, convenient to use and capable of saving heat energy.

The invention is realized by the following technical scheme:

a multi-effect evaporation energy-saving equipment is characterized in that:

a feeding cache tank, a waste steam heat exchanger, a heater, an evaporator and a condenser which are connected in sequence are arranged along the direction of the materials; the material inlet of the waste steam heat exchanger is connected with the material outlet of the feeding cache tank, and the material outlet of the waste steam heat exchanger can be connected with the material inlet of the heater;

the secondary steam outlet of the evaporator is connected with the heat medium inlet of the exhaust steam heat exchanger and the steam inlet to be condensed of the condenser through a three-way pipe, the heat medium condensate outlet of the exhaust steam heat exchanger is connected with the other material inlet of the condenser, so that part of steam formed by evaporation of the material is used as the heat medium of the exhaust steam heat exchanger to preheat the material entering the evaporator for the first time, and meanwhile, the burden of the condenser is reduced.

The multi-effect evaporation energy-saving equipment is also provided with a condensate water preheater, wherein a material inlet of the condensate water preheater is connected with a material outlet of the exhaust steam heat exchanger, and a material outlet of the condensate water preheater is connected with a material inlet of the heater; the hot medium inlet of the condensed water preheater is connected with the condensed water outlet of the heater, and the hot medium outlet of the condensed water preheater is connected with the condensed water discharge pipe, so that the condensed water formed by hot medium steam of the heater is used as the hot medium of the condensed water preheater to carry out secondary preheating on the material.

The condensed water outlet of the heater is connected with the hot medium inlet of the condensed water preheater after passing through the condensed water collecting tank.

The heaters correspond to the evaporators one by one; the material outlet of the heater is connected with the material inlet of the evaporator through the feeding pipe, the material outlet of the evaporator is connected with the material inlet of the heater through the circulating pipe, and the raw steam enters the evaporator after passing through the heater; the heater adopts a single-effect heater, and the evaporator adopts a single-effect evaporator; or the heater adopts a multi-effect heater, and the evaporator adopts a multi-effect evaporator.

When a multi-effect evaporator is adopted, a heat medium inlet of the exhaust steam heat exchanger is connected with a material secondary steam outlet of the last-effect evaporator through a three-way pipe, and a heat medium inlet of the condensate water preheater is connected with a condensate water outlet of a heater in front of the first-effect evaporator.

The bottom of the last effect evaporator is connected with the thickener through a slurry pump, the outlet at the bottom of the thickener is connected with a slurry centrifugal dehydrator, the discharge port of the slurry centrifugal dehydrator is connected with a dryer through a conveyer belt, the water outlet of the slurry centrifugal dehydrator is connected with a mother liquor tank, and the overflow port of the supernatant at the top of the thickener is also connected with the mother liquor tank; after settling and centrifugal separation, the slurry is sent to a dryer by a conveyer belt for drying.

A medium inlet of the condenser is connected with a circulating cooling water inlet pipe, a medium outlet is connected with a circulating cooling water return pipe, a condensed material outlet is connected with a feed inlet of the plate heat exchanger through a vacuum pump, and a discharge outlet of the plate heat exchanger is connected with a sewage discharge pipe; a medium inlet of the plate heat exchanger is connected with a circulating cooling water inlet pipe, and a medium outlet of the plate heat exchanger is connected with a circulating cooling water return pipe.

The waste steam heat exchanger is a primary preheater, the condensate water preheater is a secondary preheater, and the secondary preheater adopts a one-effect evaporator condensate water preheater, and the materials after primary preheating enter the tube side of the secondary preheater. The raw steam condensate water of the first-effect evaporator enters a condensate water collecting tank, a water pump outlet pipeline of the condensate water collecting tank is connected with a shell pass of the secondary preheater, the condensate water with high temperature is used as a heat medium of the secondary preheater, and the condensate water enters a tube pass of the secondary preheater to exchange heat, so that the condensate water is preheated for the second time.

The invention has the beneficial effects that 2 heat exchangers, one dead steam heat exchanger and one condensate water preheater are additionally arranged in the evaporation system. When the waste water material preheats at the exhaust steam heat exchanger, utilize partial secondary steam of last effect evaporator to get into the exhaust steam heat exchanger and regard as the hot medium, carry out a heat transfer intensification to the waste water material (thereby it preheats for another part material for the hot medium of exhaust steam heat exchanger to carry out the first time as partly steam that the waste water material evaporation formed promptly), obtain preheating for the first time, make full use of the heat energy of secondary steam, reduced the heat energy loss, and the hot medium secondary steam condensation water after the heat transfer gets into the condenser, has reduced the load of condenser.

When the wastewater material is preheated in the condensate water preheater, the heat of the condensate water of the fresh steam of the heater in front of the one-effect evaporator is utilized to heat the wastewater material for the second time; the waste water enters the evaporator at a temperature basically reaching the boiling point temperature by heat exchange and temperature rise through 2 heat exchangers, so that the evaporation is carried out smoothly. The waste water material is preheated in the condensate water preheater, and simultaneously, the temperature of the primary effect condensate water discharged out of the system is reduced, and the heat loss is reduced.

The invention relates to a concurrent multi-effect evaporation process suitable for material feeding with lower temperature. The invention utilizes the waste heat exchange process to preheat the materials, namely, the materials with higher temperature generated in the evaporation process of the system are adopted to increase the initial feeding temperature, simultaneously the temperature of the materials discharged out of the system is reduced, the problem of reutilization of some heat in the evaporation process is solved, the heat is fully utilized, the heat energy efficiency is improved, the consumption of heat energy is reduced, the consumption of fresh steam is reduced, the energy-saving effect is obvious, the treatment cost of the materials is reduced, the production cost is saved for users, and various technical performance indexes are good.

Drawings

FIG. 1 is a schematic front view of the present invention.

In the figure: 1. the system comprises a feeding buffer tank, 2. an exhaust steam preheater, 3. a condenser, 4. a condensate water preheater, 5. a first-effect heater, 6. a second-effect heater, 7. a third-effect heater, 8 first-effect evaporators, 9 condensate water collecting tanks, 10 slurry hoppers, 11 slurry filters, 12 second-effect evaporators, 13 third-effect evaporators, 14 vacuum pumps and 15 plate heat exchangers.

Detailed Description

The attached drawing is an embodiment of the invention.

The invention relates to a multi-effect evaporation energy-saving device,

a feeding cache tank 1, a waste steam heat exchanger 2, a heater, an evaporator and a condenser 3 which are connected in sequence are arranged along the direction of the materials; the material inlet of the waste steam heat exchanger is connected with the material outlet of the feeding cache tank, and the material outlet of the waste steam heat exchanger can be connected with the material inlet of the heater;

the secondary steam outlet of the evaporator is connected with the heat medium inlet of the exhaust steam heat exchanger 2 and the steam inlet to be condensed of the condenser 3 through a three-way pipe, the heat medium condensate outlet of the exhaust steam heat exchanger 2 is connected with the other material inlet of the condenser 3, so that part of steam formed by material evaporation is used as the heat medium of the exhaust steam heat exchanger 2 to preheat the material entering the evaporator for the first time, and meanwhile, the burden of the condenser is reduced.

The multi-effect evaporation energy-saving equipment is also provided with a condensate water preheater, wherein a material inlet of the condensate water preheater is connected with a material outlet of the exhaust steam heat exchanger, and a material outlet of the condensate water preheater is connected with a material inlet of the heater; the hot medium inlet of the condensed water preheater 4 is connected with the condensed water outlet of the heater, the hot medium outlet of the condensed water preheater 4 is connected with the condensed water discharge pipe, so that the condensed water of the hot medium steam of the heater in front of the evaporator is used as the hot medium of the condensed water preheater 4 to preheat the material for the second time.

The condensed water outlet of the heater is connected with the hot medium inlet of the condensed water preheater 4 through a condensed water collecting tank 9.

The heaters correspond to the evaporators one by one, material outlets of the heaters are connected with material inlets of the evaporators through feed pipes, material outlets of the evaporators are connected with the material inlets of the heaters through circulating pipes, and raw steam enters the evaporators after passing through the heaters; the heater adopts a single-effect heater, and the evaporator adopts a single-effect evaporator; or the heater adopts a multi-effect heater, and the evaporator adopts a multi-effect evaporator.

When a multi-effect evaporator is adopted, a heat medium inlet of the exhaust steam heat exchanger 2 is connected with a material secondary steam outlet of the last-effect evaporator through a three-way pipe, and a heat medium inlet of the condensate water preheater 4 is connected with a condensate water outlet of a heater in front of the first-effect evaporator.

The bottom of the last effect evaporator is connected with a thickener 10 through a slurry pump, the outlet at the bottom of the thickener is connected with a slurry centrifugal dehydrator 11, the discharge port of the slurry centrifugal dehydrator 11 is connected with a dryer through a conveyer belt, the water outlet of the slurry centrifugal dehydrator 11 is connected with a mother liquor tank, and the overflow port of the supernatant at the top of the thickener is also connected with the mother liquor tank; after settling and centrifugal separation, the slurry is sent to a dryer by a conveyer belt for drying.

A medium inlet of the condenser 3 is connected with a circulating cooling water inlet pipe, a medium outlet is connected with a circulating cooling water return pipe, a condensed material outlet is connected with a feed inlet of a plate heat exchanger 15 through a vacuum pump 14, and a discharge outlet of the plate heat exchanger is connected with a sewage discharge pipe; a medium inlet of the plate heat exchanger is connected with a circulating cooling water inlet pipe, and a medium outlet of the plate heat exchanger is connected with a circulating cooling water return pipe.

The condenser 3 is provided with a circulating cooling water medium inlet, a circulating cooling water medium outlet and a condensed material outlet.

The process for treating wastewater by using the multi-effect evaporation energy-saving equipment comprises the following steps:

in the evaporation system, when the wastewater material enters the heater and the evaporator from the feeding cache tank, the wastewater material firstly passes through the exhaust steam heat exchanger, part of secondary steam of the last-effect evaporator is utilized for primary heat exchange and temperature rise, the steam after heat exchange is condensed into water to enter the condenser, the rest of secondary steam directly enters the condenser to be condensed into water, and the two parts of water are mixed and discharged; the waste water material enters a condensate water preheater after being heated for the first time, and the waste water material is heated for the second time by utilizing the heat of the condensate water of the fresh steam of the heater in front of the first-effect evaporator; the waste water enters the evaporator through the 2 heat exchangers to exchange heat and rise temperature, and the temperature of the waste water materials entering the evaporator basically reaches the boiling point temperature through the heater, so that the evaporation is smoothly carried out.

The operation sequence of the materials in the multi-effect evaporator is that waste water steam discharged by the condensate water preheater enters the first-effect heater 5, then the waste water steam enters the first-effect evaporator 8, waste water steam discharged by the first-effect evaporator enters the second-effect heater 6 as power steam, and power steam discharged by the second-effect heater and raw steam discharged by the first-effect evaporator enter the second-effect evaporator 12 together as the power steam (the raw steam firstly enters the first-effect heater to be the power steam, and then enters the first-effect evaporator to be the power steam).

And pumping the liquid phase in the first-effect evaporator 8 into the first-effect heater 5 to continue heating and evaporating, and finally pumping the residual wastewater in the first-effect heater and the first-effect evaporator into the second-effect heater 6 to perform reduced pressure evaporation. Waste water material steam of the double-effect heater is discharged into the double-effect evaporator to be evaporated, waste water steam discharged from the double-effect evaporator is discharged into the triple-effect heater to be used as power steam, and the power steam is mixed with the power steam discharged from the double-effect evaporator after coming out of the triple-effect heater and then enters the triple-effect evaporator to be used as the power steam. The residual wastewater materials in the two-effect heater and the two-effect evaporator are pumped into the three-effect heater together for continuous evaporation, and wastewater steam evaporated by the three-effect heater enters the three-effect evaporator for continuous evaporation.

One part of the waste water vapor evaporated by the triple-effect evaporator is sent to a condenser for condensation, and the other part of the waste water vapor is preheated and fed into the buffer tank. The liquid phase left at the bottom of the triple-effect evaporator is highly concentrated slurry, the slurry is sent to a thickener 10 for sedimentation, then sent to a centrifugal dehydrator 11 for dehydration, and the obtained semi-dry material is sent to a dryer for drying. Clear liquid from the thickener and the centrifugal dehydrator can be added into a feeding buffer tank to be heated and evaporated together with other waste water.

The material temperature in the first-effect heater and the evaporator is 87-93 ℃, the evaporation pressure is about-0.01-0.03 MPa, the material temperature of the second-effect heater and the evaporator is 72-78 ℃, the evaporation pressure is about-0.05-0.07 MPa, the material temperature in the third-effect heater and the evaporator is 57-63 ℃, and the evaporation pressure is about-0.08-0.10 MPa.

The condensing temperature of the condenser 3 is 45-54 ℃, and the pressure is about-0.08-0.10 MPa. The water entering the circulating cooling water medium inlet of the condenser is 35 ℃, and the water returning from the circulating cooling water medium outlet is 39 ℃.

The heating temperature of the exhaust steam heat exchanger 2 is about 57-63 ℃, the pressure is about-0.08-0.10 MPa, the heating temperature of the condensate water preheater 4 is 100 ℃, and the pressure is normal pressure.

In the invention, the two heat exchangers (a dead steam heat exchanger and a condensate water preheater) and the heater can be replaced by plate heat exchangers or other types of heat exchangers.

2 heat exchangers, a dead steam heat exchanger and a condensate water preheater are added in the evaporation system. When the exhaust steam heat exchanger is preheated, part of the final-effect secondary steam is condensed, and the load of the condenser is reduced. Meanwhile, when the condensate water preheater is used for preheating, the temperature of the primary condensate water discharged out of the system is reduced, and the heat loss is reduced.