Background technology
China has been the big country of iron and steel and Chemical Manufacture.
The annual production of iron and steel accounts for 40% of Gross World Product.No matter be steel-making or ironmaking, all will produce a large amount of slags.Slag is generation of accompanying with iron and steel, it is the byproduct of smelting iron and steel, it is again the primary condition of a series of important metallurgical reaction, it participates in physical-chemical reaction and the mass-and heat-transfer process of steel smelting procedure directly, it not only has influence on iron and steel output, quality, and has close relationship with the consumption of raw material, energy.
In Ferrous Metallurgy stove, produce the high temperature furnace slag of 1400-2000 DEG C, after cinder notch flows out, again when slag runner enters flushing cinder chute, with certain water yield, hydraulic pressure and the chute gradient, water is made to become certain angle of cut with slag stream, slag, by cold shock, bursts into the qualified grain slag of certain particle size.After pulp water is separated, slag is used as construction material; Carry out the washing slag water of heat exchange with high temperature furnace slag, enter flushing cinder pond.Flushing cinder pond takes up an area several thousand square metres usually; above flushing cinder pond, hot vapour soars; such washing slag water is the warm effluent that temperature remains on 60-70 DEG C throughout the year, is a huge potential heat energy energy; if can effectively be used; such as utilizing the heat energy of washing slag water, winter is residential block heating, can be not only that country saves a large amount of fuel; and decrease carbon emission, protect environment.
The heat energy recycle problem of washing slag water, is not also well solved so far.
Due to washing slag water Reusability, dissolved into the plurality of inorganic salt and oxide that contain in slag in washing slag water, defining is almost saturated saline-alkali water solution.When slag bursts in grain slag process by cold shock, some tiny slag enters in water and suspends.Detect through reality, washing slag water turbidity is 60-80mg/l.
Certain enterprise that heats, by dividing wall type heat exchanger, passes to recirculated water by the heat of washing slag water, utilizes recirculated water to heat to residential block.In an only winter, less than the heating duration of 4 months, the washing slag water side of dividing wall type heat exchanger, fouling reached 3-5 centimetre, and dirty layer is hard, fluffs loose after weathering.Think afterwards by analysis, the composition of washing slag water fouling in heat exchanger is the multiple inorganic salts containing the crystallization water, such as, containing the silicate of the crystallization water.The crystallization incrustation scale that washing slag water is hard, makes dividing wall type heat exchanger almost scrap completely.
Someone attempts there is metre filter washing slag water, to solve washing slag water scaling problem on heat exchangers.Washing slag water is the saline-alkali water of Multiple components, and for saline-alkali water, filter is not used completely.Saline-alkali water can pass through any filter smoothly, and it is inner to have arrived heat exchanger, runs into cold heat exchanger wall, and saline-alkali water is lowered the temperature, supersaturation, at once crystallization on cold wall.
Chemical industry chemical fertilizer production enterprise, is distributed in a lot of counties and cities, in its production process, produces a large amount of middle low-temperature wastewater.Such as, semiwater gas method is utilized to produce the chemical plant of ammonia and nitrogenous fertilizer, at high-temperature water gas by spray column cleaning process, produce a large amount of 40-70 DEG C of very dirty middle low-temperature wastewater, when utilizing ordinary heat exchanger to reclaim waste water heat, heat exchanger is contaminated, reduces heat-transfer capability, also often block, can not work.Especially, when water temperature is lower than 50 DEG C, utilize heat exchanger heat exchange, heating is not worth.
As mentioned above, in industrial or agricultural and people's lives, discharge various middle low-temperature wastewater, because the impurity component contained in low-temperature wastewater in these is complicated, if utilize common dividing wall type heat exchanger to reclaim heat energy, heat exchanger partition is the cisco unity malfunction by scaling fouling soon; And when wastewater temperature is lower, utilize heat exchanger to reclaim heat, the requirement of user for heat supply temperature can not be met.
The above-mentioned background technology about Sewage heat energy recycle, has a detailed description in following monograph:
1, Yu Jianzu writes, heat exchanger principle and design, Beijing: publishing house of BJ University of Aeronautics & Astronautics, 2010.
2, Chen Dong chief editor, heat pump techniques, Beijing: Chemical Industry Press, 2012.
Summary of the invention
In order to the recovery problem of low-temperature wastewater heat energy in solving, the present invention provides a kind of steam jet heat pump.
A kind of steam jet heat pump, its primary structure comprises: evaporimeter, condenser and steam jet ejector.
Steam jet ejector utilizes high steam as working steam, injection low-pressure steam, and the middle pressure steam of formation flows out from injector; Middle low-temperature wastewater enters evaporation in evaporimeter and produces low-pressure steam, low-pressure steam in steam jet ejector by working steam injection, condenser condensation heat is entered after the two mixing, for heating recirculated water, it is characterized in that: said condenser, it is in series up and down by three dividing wall type heat exchangers.
Evaporimeter is vertical pressure vessel, it is in series up and down by three vaporization chambers, and its structure comprises: water inlet pipe, upper cover, cylindrical shell, the first sieve plate, the first vaporization chamber, the first steam (vapor) outlet, the second sieve plate, the second vaporization chamber, the second steam (vapor) outlet, the 3rd sieve plate, the 3rd vaporization chamber, the 3rd steam (vapor) outlet, low head and drainpipe.
Middle low-temperature wastewater enters evaporimeter by water inlet pipe, by the first sieve plate, enters evaporimeter first vaporization chamber, and part evaporation produces steam, is flowed out by the first steam (vapor) outlet; First vaporization chamber evaporation residue waste water, enter the second vaporization chamber, the steam that the second vaporization chamber evaporation produces is flowed out by the second steam (vapor) outlet; Second vaporization chamber evaporation residue waste water, enter the 3rd vaporization chamber, the steam that the 3rd vaporization chamber evaporation produces is flowed out by the 3rd steam (vapor) outlet; Finally remain waste water in 3rd vaporization chamber, flow out from the drainpipe of bottom.
Condenser is vertical pressure vessel, and its structure comprises: upper cover, cylindrical shell, the first steam inlet, the first condensation chamber, the first dividing wall type heat exchanger, the first base plate, the first weep hole, the first connecting water pipe, the second steam inlet, the second condensation chamber, the second dividing wall type heat exchanger, the second base plate, the second weep hole, the second connecting water pipe, the 3rd steam inlet, the 3rd condensation chamber, the 3rd dividing wall type heat exchanger, water inlet pipe, outlet pipe, low head, vacuum exhaust pipe and condensate pipe.
Heating recirculated water backwater, enters condenser from bottom water inlet pipe, enters the 3rd dividing wall type heat exchanger, by partition and steam heat-exchanging, steam condensation trickles downwards, and heating recirculated water is again by the second connecting water pipe, upwards enter the second dividing wall type heat exchanger, continue through partition and steam heat-exchanging, then by the first connecting water pipe, upwards enter the first dividing wall type heat exchanger, by partition and steam heat-exchanging, finally, the heating recirculated water be heated by steam, is flowed out by outlet pipe.
By the first steam inlet, enter the steam of the first condensation chamber of condenser, vertically flow into the steam flow channel penetrating up and down of the first dividing wall type heat exchanger downwards, by partition to the heat transfer of heating recirculated water, condense after steam heat release, to face down trickling along heat exchange wall, flow to the first base plate, by the first weep hole, flow to the steam side of the second dividing wall type heat exchanger downwards.
By second, third steam inlet, enter the steam of second, third condensation chamber of condenser, by second, third dividing wall type heat exchanger to the heat transfer of heating recirculated water, steam heat release is condensed.
The condensate water that whole steam condensation produces, is discharged by the condensate pipe bottom low head.
On sidewall bottom condenser, pick out vacuum exhaust pipe, extract the on-condensible gas in condenser out.
Steam jet ejector, its structure comprises: steam inlet pipe, nozzle, suction chamber, diffuser pipe entrance, diffuser pipe throat and diffuser pipe divergent segment.
From the high-pressure work steam that steam boiler comes, by steam inlet pipe and nozzle, nozzle is contraction and enlargement nozzle, at nozzle exit, form the supersonic speed vapor stream of high velocity jet, make to form low-pressure area in suction chamber, evaporated vapor in injection evaporimeter enters suction chamber, and after mixing with working steam, enter diffuser pipe entrance to mix further, in diffuser pipe throat, become velocity of sound flowing vapor stream, then diffuser pipe divergent segment is entered, flow velocity reduces pressure increase, reach a middle pressure, it is lower than working steam pressure, but it is higher than evaporator evaporation pressure, then steam pipeline is passed through, enter condenser.
Detailed description of the invention
Below in conjunction with drawings and Examples, the present invention is described in further detail.
Fig. 1 gives the overall construction drawing of steam jet heat pump embodiment of the present invention.
The general structure of steam jet heat pump embodiment of the present invention, is divided into left and right two major parts in shape: left is vertical evaporimeter 100, and right is vertical condenser 300, and there is steam jet ejector 200 centre.
Steam jet ejector 200 is injection and the power-equipment of compressed steam, it has three import and export, import is that the high steam that provides from steam boiler is as working steam, another import is the low-pressure steam in injection evaporimeter, and unique outlet is that the middle pressure steam after working steam and jetting steam caused mixing are compressed enters condenser from injector outflow.
Middle low-temperature wastewater enters evaporimeter 100 by water inlet pipe 110, is entered the first vaporization chamber 135 in evaporimeter 100 by the first sieve plate 130.Under the ejector action of steam jet ejector 200, the pressure in vaporization chamber 135 lower than saturation pressure corresponding to low-temperature wastewater temperature in import, so middle low-temperature wastewater enters part evaporation at once after vaporization chamber 135, also referred to as being flash distillation or dilatation.The steam that evaporation produces, by the first steam jet ejector 200, enters the first condensation chamber 305 of condenser 300 together with working steam.
Second, third vaporization chamber of evaporimeter 100 evaporates the steam of generation equally, successively by second, third steam jet ejector, enters second, third condensation chamber of condenser 300 together with working steam.
The remaining saturated waste water of first, second, third vaporization chamber flash distillation of evaporimeter 100, trickles downwards successively, finally enters the ponding room bottom evaporimeter 100, then flow out downwards from the drainpipe 170 of bottom.Because the difference in height of draining produces static pressure, wastewater pressure raises, and becomes unsaturated water, then discharges through suction pump.
The backwater of heating recirculated water, by feed pump, enters vertical (type) condenser 300 from the water inlet pipe 345 of condenser 300 bottom, and in condenser 300, from bottom to top, heating recirculated water is connected in series through three dividing wall type heat exchangers successively.After three dividing wall type heat exchangers, by warmed-up heating recirculated water in condenser 300, by condenser 300 top outlet pipe 325, outwards provide heating hot water.
The steam produced in evaporimeter 100 first vaporization chamber 135, together with working steam, after entering the first condensation chamber 305 of condenser 300 from the first steam jet ejector 200 level, downward inflow first dividing wall type heat exchanger 320, by partition and recirculated water heat exchange, steam heat release is also condensed, and trickles downwards.
Equally, the steam produced in second, third vaporization chamber of evaporimeter 100, together with working steam, after second, third condensation chamber that second, third steam jet ejector level enters condenser 300, second, third dividing wall type heat exchanger of downward inflow, by partition and recirculated water heat exchange, after steam heat release is also condensed, condensate water is trickled downwards.
Finally, flow to the condensate water gathered bottom condenser 300, by condensate pipe 365, discharge through condensate pump.
On the lower sides of condenser 300, there is a vacuum exhaust pipe 355.The on-condensible gas in condenser constantly extracted out by vavuum pump by vacuum exhaust pipe 355, the dissolved gas that in being exactly mainly, low-temperature wastewater is separated out, and leaked-in air in system, thus can ensure intrasystem vacuum.
In steam jet heat pump embodiment of the present invention, evaporimeter and condenser are upper and lower three grades, also can be two-stage up and down, or be four, Pyatyi.
Steam jet heat pump workflow is summarized as follows:
1, middle low-temperature wastewater enters evaporimeter 100 by inlet channel from top;
2, the pressure in evaporimeter 100 is low, and middle low-temperature wastewater partly evaporates after entering evaporimeter at once;
3, the steam produced in evaporimeter 100, together with working steam, by steam jet ejector 200, enters condenser 300;
4, in evaporimeter 100, residue waste water, flows out downwards from the drainpipe 170 of bottom;
5, heating recirculated water enters condenser 300 by condenser 300 water inlet pipe 345;
6, condenser 300 is dividing wall type heat exchanger, and the side of partition is evaporimeter steam, and opposite side is heating recirculated water;
7, by warmed-up heating recirculated water in condenser 300, flowed out by outlet pipe 325;
8, in the below of condenser 300, there is vacuum exhaust pipe 355, extract the on-condensible gas in condenser out by vavuum pump;
9, the steam condensate in condenser 300, is flowed out by condensate pipe 365 and condensate pump.
Fig. 2 gives the evaporation structure figure of steam jet heat pump embodiment of the present invention.
The evaporimeter of steam jet heat pump embodiment of the present invention, its profile is a vertical pressure vessel, and its structure comprises: water inlet pipe 110, upper cover 120, cylindrical shell 150, first sieve plate 130, first vaporization chamber 135, first steam (vapor) outlet 140, second sieve plate, the second vaporization chamber, the second steam (vapor) outlet, the 3rd sieve plate, the 3rd vaporization chamber, the 3rd steam (vapor) outlet, low head 160 and drainpipe 170.
Middle low-temperature wastewater enters evaporimeter by water inlet pipe 110, the first vaporization chamber 135 in evaporimeter is entered again by the first sieve plate 130, pressure in vaporization chamber 135 is lower than saturation pressure corresponding to low-temperature wastewater temperature in import, so, middle low-temperature wastewater partly evaporates, at once also referred to as being flash distillation or dilatation after entering vaporization chamber 135.
The steam that the evaporation of evaporimeter first vaporization chamber 135 produces, by the first steam (vapor) outlet 140, then enters the first condensation chamber of condenser by the first steam jet ejector.
Evaporimeter first vaporization chamber 135 evaporates remaining saturated waste water, passes downwardly through sieve plate at different levels, trickles downwards successively.
The steam that the evaporation of evaporimeter second vaporization chamber produces, by the second steam (vapor) outlet, then enters the second condensation chamber of condenser by the second steam jet ejector.
The remaining saturated waste water of evaporimeter second vaporization chamber evaporation, passes downwardly through sieve plate at different levels, trickles downwards successively.
The steam that the evaporation of evaporimeter the 3rd vaporization chamber produces, by the 3rd steam (vapor) outlet, then enters the 3rd condensation chamber of condenser by the 3rd steam jet ejector.
The remaining saturated waste water of evaporimeter the 3rd vaporization chamber evaporation, trickles downwards.
Finally, three grades of remaining saturated waste water of evaporation, flow out downwards from the drainpipe 170 of bottom.Because falling head difference produces static pressure, wastewater pressure raises, and becomes unsaturated water, then discharges through suction pump.
Sieve plate is porous plate, and its effect is:
1, for given discharge, the water layer on sieve plate should be 2 ~ 5 cm thicks, to ensure that the vapor phase space of upper and lower vaporization chamber does not communicate;
2, the water surface that sieve plate flows down, should have enough areas, to ensure the heat exchange needs between steam and water;
3, the diameter of the discharge orifice of sieve plate, is generally 6 ~ 8 millimeters, can not be little 6 millimeters, to prevent blocking.
Fig. 3 gives the condenser structure figure of steam jet heat pump embodiment of the present invention.
The condenser of steam jet heat pump embodiment of the present invention, it is three sections of vertical tandem dividing wall type heat exchangers, its profile is a pressure vessel, its structure comprises: upper cover 310, cylindrical shell 315, first steam inlet 350, first condensation chamber 305, first dividing wall type heat exchanger 320, first base plate 330, first weep hole 335, first connecting water pipe 340, second steam inlet, second condensation chamber, second dividing wall type heat exchanger, second base plate, second weep hole, second connecting water pipe 342, 3rd steam inlet, 3rd condensation chamber, 3rd dividing wall type heat exchanger, water inlet pipe 345, outlet pipe 325, low head 360, vacuum exhaust pipe 355 and condensate pipe 365.
The low-temperature return water of heating recirculated water, by feed pump, enters condenser from bottom water inlet pipe 345, enters the 3rd dividing wall type heat exchanger bottom of the dividing wall type heat exchanger of upper and lower three series connection.In the 3rd dividing wall type heat exchanger, heating recirculated water is by partition and steam heat-exchanging, and steam condensation heat release, the heat of steam improves circulating water temperature, and steam condensate is trickled downwards by steam channel vertical in dividing wall type heat exchanger.After flowing through the 3rd dividing wall type heat exchanger, by preliminarily heated heating recirculated water, by the second connecting water pipe 342, upwards enter the second dividing wall type heat exchanger, continue through partition and steam heat-exchanging.Flow through the second dividing wall type heat exchanger, the heating recirculated water be further heated, by the first connecting water pipe 340, upwards enter the first dividing wall type heat exchanger, continue through partition and steam heat-exchanging.Finally, the heating recirculated water be sufficiently heated, is flowed out by outlet pipe 325, to heat user heat supply.
The steam of the first vaporization chamber evaporation generation of evaporimeter, together with working steam, by the first steam jet ejector, by the first steam inlet 350, after entering the first condensation chamber 305 of condenser, vertically flow into the steam flow channel penetrating up and down of the first dividing wall type heat exchanger 320 downwards, by partition to the heat transfer of heating recirculated water, condense after steam heat release, to face down trickling along heat exchange wall, flow to the first base plate 330, by the first weep hole 335, flow to the steam side of the second dividing wall type heat exchanger downwards.
The function of weep hole is: 1, and ensure that the condensate water on top is all downward through, ponding thickness can not exceed standard; 2, ensure that the upper and lower vapor space does not communicate, can not pressure release.The shape and size of weep hole need appropriate design.
Equally, the steam of second, third vaporization chamber evaporation generation of evaporimeter, together with working steam, by second, third steam jet ejector, by second, third steam inlet of condenser, after entering second, third condensation chamber, vertically flow into the steam flow channel penetrating up and down of second, third dividing wall type heat exchanger downwards, by partition to the heat transfer of heating recirculated water, condense after steam heat release, condensate water to face down trickling along heat exchange wall.
Finally, the condensate water of all steam side condensation generations of upper and lower three grades of dividing wall type heat exchangers, is flow to the retaining room in low head 360 together, then is discharged by condensate pipe 365 and condensate pump.
On the sidewall of the upper space of the retaining room in low head 360, pick out vacuum exhaust pipe 355.The on-condensible gas in condenser constantly extracted out by vavuum pump by vacuum exhaust pipe 355, be exactly mainly the on-condensible gas carried secretly in steam, and leaked-in air in system, thus intrasystem vacuum can be ensured, ensure evaporimeter flash temperature, ensure condensation dividing wall type heat exchanger efficient heat transfer.
Fig. 4 is the steam jet ejector structure chart of steam jet heat pump embodiment of the present invention.
The steam jet ejector of steam jet heat pump embodiment of the present invention, its structure comprises: steam inlet pipe 210, nozzle 220, suction chamber 225, diffuser pipe entrance 230, diffuser pipe throat 235 and diffuser pipe divergent segment 240.
From the high-pressure work steam that steam boiler comes, by steam inlet pipe 210 and nozzle 220, the supersonic speed vapor stream of high velocity jet is formed in suction chamber 225, make to form low-pressure area in suction chamber 225, evaporated vapor in injection evaporimeter 100 enters suction chamber 225, and after mixing with working steam, enter diffuser pipe entrance 230 to mix further, in diffuser pipe throat 235 uiform section flowing, become velocity of sound flowing vapor stream, then enter diffuser pipe divergent segment 240 flow velocity to reduce, pressure increase, reach a middle pressure, it is lower than working steam pressure, but it is higher than evaporator evaporation pressure, then by steam pipeline 250, enter condenser 300.
Nozzle 220 is contraction and enlargement nozzles, the ratio of the working steam pressure and the steam pressure in suction chamber 225 that usually come from steam boiler, namely with the ratio of the evaporating pressure in evaporimeter 100, be greater than critical pressure ratio, after working steam leads to contraction and enlargement nozzle 220, working steam flow velocity becomes supersonic speed from subsonic speed, more can steam effectively in injection evaporimeter, has higher operating efficiency.