CN1322199C - Pressure stabilizing method and its device for beating of disc mill - Google Patents

Abstract

The invention provides a beating and pressure stabilizing device for a disc refiner, which is arranged in front of the disc refiner and connected with the inlet of the disc refiner, including a pulp inlet pipe, a pressure stabilizing tower, an overflow pipe, a control valve, and a pulp outlet pipe. The slurry inlet pipe is connected to the top opening of the pressure stabilizing tower, the overflow pipe is connected to the top of the pressure stabilizing tower, and its diameter is larger than that of the slurry inlet pipe, and the control valve is installed on the overflow pipe. The aforementioned device controls the beating pressure through the height of the stabilizing tower or controls the beating pressure by controlling the opening of the overflow port. The invention can obviously eliminate and reduce the fluctuation of the flow and pressure of incoming pulp, make the disc refiner work under a relatively stable flow and pressure when beating, obtain stable beating quality, and reduce the instability rate of beating quality by more than 80% , reducing energy consumption by 5% to 15%, has the advantages of fewer components, easy manufacture, simple assembly, and convenient implementation.

Description

Pulping Pressure-stabilizing Method And Device of Disc Grinder

Technical field

The present invention relates to a kind of papermaking making beating technology, particularly a kind of Pulping Pressure-stabilizing Method And Device of Disc Grinder.

Background technology

Medium consistency refining obtains more and more widely application in the paper-making industry of China in recent years; Because paper pulp is a kind of suspension, when concentration raise, its stability that flows was vulnerable to disturb; In addition, because a variety of causes, at beater floor, fluctuation can appear in the flow of slurry and pressure, when supplying slurry with stock pump, stock pump can not be subdued this fluctuation, even also can amplify this fluctuation, in this case, disc mill is operated under unsettled flow and the pressure, and in pull an oar under the dense condition, pressure obviously influences beating results because under the dense condition, between the fiber and the rubbing action between the fiber floc sedimentation contribution of making beating effect is increased, cutter weakens relatively to the shear action of fiber, and beating pressure directly influences rubbing action, so, the instability of pressure, directly have influence on the stable of refining pulp quality, and in this fluctuation change procedure, cause the waste of a large amount of energy consumptions; Another kind of is to utilize the pump function of disc mill (size of pumpability is by the shape and the inclination angle decision of roll flute) for the slurry mode, pass through self-priming apparatus, self-priming is for slurry, this comparatively steady for the slurry mode, but need before disc mill, be provided with a feed tower, when slurry position in the tower and flow generation fluctuation, also can produce and the same problem of preceding a kind of mode.In order to address this problem, there is dual mode available in theory, the one, utilize kinetic-control system, by the flow and the pressure of instrument test slurry, adjust the operating parameter of disc mill according to flow that changes and pressure.Thereby reach the purpose of stablizing specific energy and refining pulp quality, adopt this mode to need advanced disc mill making beating control system, this control system is because complicated operation, and cost cost height is very deficient in particularly middle or small paper mill, the paper mill of China; And another kind of mode, the flow and the pressure of promptly managing stable slurry before disc mill are a kind of both economical feasible methods.

Summary of the invention

The objective of the invention is to overcome the shortcoming of prior art, provide a kind of simple to operate, implement convenient, cost is low, the disc mill making beating method for stabilizing voltage that is easy to apply.

Another object of the present invention is to provide a kind of disc mill making beating stable-pressure device of realizing said method.

Purpose of the present invention is achieved through the following technical solutions: this disc mill making beating stable-pressure device is arranged on before the disc mill and with the disc mill inlet and is connected, comprise pulp-inlet pipe, pressure-stabilizing tower, overflow pipe, control valve, grout outlet, described pulp-inlet pipe is connected with the close top open part of pressure-stabilizing tower, described overflow pipe is connected in the top of pressure-stabilizing tower, and control valve is installed on the overflow pipe.

The caliber of described overflow pipe is greater than the caliber of pulp-inlet pipe.

The bottom of described pressure-stabilizing tower is an inverted cone shape, connects a bend pipe in the exit of bottom, and the other end of described bend pipe and a reducer pipe join, to guarantee that slurry enters disc mill smoothly.

Especially, when this disc mill making beating stable-pressure device utilized the height of pressure-stabilizing tower to realize controlling beating pressure, its structure can be simplified, and does not comprise the control valve on the overflow pipe, or the aperture of control valve is remained unchanged, that is the flow of overflow pipe does not need to be controlled.

The diameter of described pressure-stabilizing tower determines for the slurry position undulating value that the fluctuation variable quantity and the pressure-stabilizing tower of slurry allows according to stock pump, and described pressure-stabilizing tower tower body portion height overall is by determining for the slurry undulate quantity; Be specially: (1) during as beating pressure, the height of this pressure-stabilizing tower comes to determine by the following method with tower height: because disc mill itself can produce pump action, so, measure the pumping pressure head h that the disc mill of work itself can produce at first by experiment _Dish(unit: rice) when the specification alteration of form of mill, need carry out determination experiment, again according to formula h _Slurry=h _{Go out}+ h _Decrease-h _Dish+ h _Beat, h wherein _{Go out}Be the height of disc mill pulp need pumping, h _DecreaseBe manifold pressure loss, h _BeatBe beating pressure, unit is a rice, h _SlurryBe the slurry position that should keep in the pressure-stabilizing tower, suppose that it is h1 that the slurry position changes permissible value, then the height h=h of pressure-stabilizing tower _Slurry+ h1.(2) with tower height during as beating pressure, the diameter of this pressure-stabilizing tower comes to determine by the following method: because the flow of stock pump fluctuates, suppose that stock pump flow at a time is F (t), in time period t ₀In, the flow of stock pump is And supposition $Q_{\max }={\&Integral;}_0^{0}F\left(t\right)\mathrm{dt},$ Suppose that the unit stock volume to disc mill is q, then in time period t ₀Interior flow is qt ₀, the maximum of setting the variation of pressure-stabilizing tower entoplasm position is h1, according to the mass balance principle, can calculate the diameter of pressure-stabilizing tower, its computing formula is: $D=2\sqrt{\frac{Q_{\max }-q{t}_0}{\mathrm{\&pi;}{h}_1}}.$ If h ₃For being lower than h in the variation of slurry position _SlurryMaximum, suppose in time period t ₀In, the flow minimum of stock pump, then $Q_{\max }={\&Integral;}_0^{0}F\left(t\right)\mathrm{dt},$ Then $h_3=\frac{4(q{t}_0-Q_{\min })}{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="2"\; label="D"\; filenames="C20041005244100091.png"\; state="\{\{state\}\}">D</figure-callout>}}^2},$ It is h2 that pressure-stabilizing tower slurry position changes total height, h ₂=h ₁+ h ₃, pressure-stabilizing tower volume height can be designed to more than or equal to h2.(3) when adopting by overfall aperture decision beating pressure, when valve opening hour, the pressure maximum of control, the spillway discharge of suppose this moment be disc mill flow 10%, h1 is the maximum permission of a pressure undulate quantity, the diameter that then can calculate pressure-stabilizing tower should be not less than $D_0=2\sqrt{\frac{Q_{\max }-1.1q{t}_0}{\mathrm{\&pi;}{h}_1}}.$ Q wherein _MaxAs mentioned above; When the aperture of valve is maximum, the pressure minimum of control, when in time period t 0, the stock pump flow is Q _MinThe time, suppose that the quantity of reflux of this moment is 0.5q, then voltage stabilizing tower height h5 should satisfy

So,

Utilize said apparatus to realize that disc mill making beating method for stabilizing voltage is for controlling beating pressure by the height control beating pressure of pressure-stabilizing tower or by control overfall aperture.

When employing is controlled beating pressure by the height of pressure-stabilizing tower, the control valve standard-sized sheet of overflow pipe, eliminate or reduce the flow starched by pumping and the fluctuation of pressure by pressure-stabilizing tower, make the slurry position variation in the pressure-stabilizing tower remain on fluctuation in certain allowed band, reach disc mill and advance to starch the relatively stable of pressure and flow.This pressure-stabilizing tower is a downflow tower, and the pressure-stabilizing tower stock inlet is at the tip position near tower, and the top of pressure-stabilizing tower is determined by the pressure oscillation maximum of advancing to starch that allows from the distance of normal slurry position, for example, the slurry position is designed to 8 meters, and the fluctuation maximum of permission is 0.5 meter, and then the distance of cat head syneresis position is 0.5 meter; Top design overfall at tower, and be connected with overflow pipe, its effect is: when stock inlet is starched fluctuation when unusual, for being no more than, the variation that does not make the slurry position allows setting value (aforesaid 0.5 meter), by overflow pipe with too much backflow of slurry to leading portion operation or slurry tower, thereby the variation that guarantees the slurry position can not surpass and allows setting value, the bore of overfall and overflow pipe and greater than the stock inlet footpath, when avoiding overflow occurring like this,, overflow ducts increases the interior pressure of pressure-stabilizing tower owing to diminishing.

When adopting by overfall aperture control beating pressure, be full of slurry in the pressure-stabilizing tower, the size of regulating spillway discharge by the aperture of regulating flow spill valve is controlled the pressure of slurry in the pressure-stabilizing tower, this pressure is beating pressure, this moment, the slurry ability that supplies of stock pump was greater than the production capacity of disc mill, and the height of pressure-stabilizing tower no longer determines making beating to press; The height of pressure-stabilizing tower is by producing and process conditions are determined, the determining of its diameter will be considered the fluctuation maximum of stock pump outlet slurry and the spillway discharge of control, and diameter is too small, can not eliminate the pressure variation that the flowed fluctuation of stock pump causes, excessively causes unnecessary waste.

The relative prior art of the present invention has following advantage and effect: (1) treatment effect is obvious; Utilize the present invention obviously to eliminate and reduce the flow starched and the fluctuation of pressure, be in the work down of a metastable flow and pressure when making the disc mill making beating, because the flow and the pressure influence refining pulp quality of slurry, so, disc mill is worked under stable flow rate and pressure, just can obtain stable refining pulp quality.Prove that through production practices the present invention has overcome directly the flow that brings for slurry to disc mill and the fluctuation of pressure, and the unstable rate of refining pulp quality is reduced more than 80%, cuts down the consumption of energy 5%～15%.(2) simple in structure, cost is low; The composition member of apparatus of the present invention is few, easy to manufacture, and assembling is simple, and it is convenient to implement.

Description of drawings

Fig. 1 is the structural representation of disc mill making beating stable-pressure device of the present invention.

Fig. 2 is another structural representation of disc mill making beating stable-pressure device of the present invention.

The specific embodiment

The present invention is described in further detail below in conjunction with embodiment and accompanying drawing, but embodiments of the present invention are not limited thereto.

Embodiment 1

Fig. 1 shows a kind of specific embodiment of the present invention, as seen from Figure 1, disc mill making beating stable-pressure device of the present invention comprises pulp-inlet pipe 1, overflow pipe 2, pressure-stabilizing tower 3, grout outlet 4, pulp-inlet pipe 1 one ends link to each other with the outlet of stock pump or leading portion operation, the other end links to each other near top open part with pressure-stabilizing tower 3, overflow pipe 2 is connected in the top of pressure-stabilizing tower 3, and its caliber is greater than the caliber of pulp-inlet pipe 1, and the changing value that beating pressure that the height of pressure-stabilizing tower 3 and diameter will be kept by native system and pressure allow decides.The bottom design of pressure-stabilizing tower 3 becomes inverted cone shape, connects the bend pipe in a big curved footpath in the exit of bottom, joins with a reducer pipe, to guarantee that slurry enters disc mill smoothly again.Concrete workflow is as follows: by stock tank or be pumped into or flow to by the outlet of leading portion operation the top of pressure-stabilizing tower 3 through stock pump by the slurry that leading portion workshop section sends here, fall again stream and descend, when the flow of starching does not fluctuate, the slurry position of pressure-stabilizing tower 3 remains unchanged, and the slurry that pumping comes keeps dynamic equilibrium with the slurry that flows out pressure-stabilizing tower 3; When fluctuation appears in the flow of starching, also can fluctuate in slurry position in the pressure-stabilizing tower 3, but in pressure-stabilizing tower 3, this fluctuation will be greatly reduced, in the time of will making the disc mill making beating at last, the flow and the pressure of slurry maintain a relatively stable state, and significantly reduce the direct refining pulp quality that causes for slurry and fluctuate, and save power consumption.When the slurry of starching flows unusually when big, redundant sizing agent is back to the leading portion operation or gets back to stock tank by overflow pipe 2, thereby keeps the unlikely variation in slurry position in the pressure-stabilizing tower 3 too big.

Embodiment 2

Fig. 2 shows the another kind of specific embodiment of the present invention, as seen from Figure 2, disc mill making beating stable-pressure device of the present invention comprises pulp storage tower 5, stock pump 6, pulp-inlet pipe 1, overflow pipe 2, control valve 7, pressure-stabilizing tower 3, grout outlet 4, pulp-inlet pipe 1 one ends link to each other with stock pump 6, the other end links to each other near top open part with pressure-stabilizing tower 3, overflow pipe 2 is connected in the top of pressure-stabilizing tower 3 and control valve 7 is installed, beating pressure and the changing value of pressure permission and the minimum and maximum value of the quantity of reflux that control valve is controlled that the height of pressure-stabilizing tower 3 and diameter will be kept by native system, the undulate quantity of stock pump decides.The bottom design of pressure-stabilizing tower 3 becomes inverted cone shape, connects the bend pipe in a big curved footpath in the exit of bottom, joins with a reducer pipe, to guarantee that slurry enters disc mill smoothly again.Concrete workflow is as follows: by stock tank or be pumped into the top of pressure-stabilizing tower 3 through stock pump 6 by the slurry that leading portion workshop section sends here, slurry is full of whole pressure-stabilizing tower 3, this moment adjusting control valve 7 aperture, the size of adjusting spillway discharge is controlled the slurry pressure in the pressure-stabilizing tower 3, slurry is pressed reach required value, when the flow of starching did not fluctuate, the pressure in the pressure-stabilizing tower 3 remained unchanged; When fluctuation appearred in the flow of starching, pressure-stabilizing tower 3 can make this fluctuation significantly reduce, and in the time of will making the disc mill making beating at last, the flow and the pressure of slurry maintain a relatively stable state, and significantly reduced the direct refining pulp quality fluctuation that supplies slurry to cause, and saved power consumption.The slurry undulate quantity of stock pump 6 pumpings is back to the leading portion operation or gets back to stock tank by overflow pipe 2, thereby keeps the slurry in the pressure-stabilizing tower 3 to press unlikely variation too big.When changing beating pressure, need readjust the aperture of overflow valve, that is change spillway discharge again, make the pressure in the pressure-stabilizing tower 3 remain on new stationary value.

Claims (7)

1, a kind of disc mill making beating stable-pressure device, it is characterized in that: be arranged on before the disc mill and and be connected with the disc mill inlet, comprise pulp-inlet pipe, pressure-stabilizing tower, overflow pipe, control valve, grout outlet, described pulp-inlet pipe is connected with the opening at the close top of pressure-stabilizing tower, described overflow pipe is connected in the top of pressure-stabilizing tower, and control valve is installed on the overflow pipe; When with tower height during as beating pressure, the high computational formula of described pressure-stabilizing tower is h _Slurry=h _{Go out}+ h _Decrease-h _Dish+ h _Beat+ h ₁, h wherein _{Go out}Be the height of disc mill pulp need pumping, h _DecreaseBe the loss of pipeline inner ram, h _BeatBe beating pressure, h _DishBe the pressure head that disc mill itself produces, h ₁Be the changing value that the slurry position allows, unit is rice; Described pressure-stabilizing tower Diameter Calculation formula is $D=2\sqrt{\frac{Q_{\max }-q{t}_0}{\mathrm{\&pi;}{h}_1}}$ , wherein D is the pressure-stabilizing tower diameter, Q _MaxBe at t ₀Enter the maximum stream flow of pressure-stabilizing tower in time period, q is the throughput of disc mill, h ₁Changing value for the permission of slurry position; When with overflow valve aperture decision beating pressure, the diameter of described pressure-stabilizing tower should be not less than $D_0=2\sqrt{\frac{Q_{\max }-(1+k){\mathrm{qt}}_0}{\mathrm{\&pi;}{h}_1}},$ Q wherein _Max, q, t ₀, h ₁Meaning as previously mentioned, k is the overflow ratio, promptly from the flow of overflow pipe overflow and the ratio of disc mill slurry-outlet quantity; The height of described pressure-stabilizing tower is Wherein h4 is the distance of the bottom of pressure-stabilizing tower far from bottom tube connector horizontal segment center line.

2, disc mill making beating stable-pressure device according to claim 1, it is characterized in that: the bottom of described pressure-stabilizing tower is an inverted cone shape, connects a bend pipe in the exit of bottom, the other end of described bend pipe and a reducer pipe join.

3, disc mill making beating stable-pressure device according to claim 1, it is characterized in that: the caliber of described overflow pipe is greater than the caliber of pulp-inlet pipe.

4, disc mill making beating stable-pressure device according to claim 1, it is characterized in that: the aperture of described control valve remains unchanged.

5, a kind of method for stabilizing voltage that utilizes each described disc mill making beating stable-pressure device of claim 1～4 to realize is characterized in that: control beating pressure by the height control beating pressure of pressure-stabilizing tower or by control overfall aperture.

6, method for stabilizing voltage according to claim 5, it is characterized in that: when employing is controlled beating pressure by the height of pressure-stabilizing tower, the control valve standard-sized sheet of overflow pipe, eliminate or reduce the flow starched by pumping and the fluctuation of pressure by pressure-stabilizing tower, slurry position in the pressure-stabilizing tower is changed remain on fluctuation in certain allowed band.

7, method for stabilizing voltage according to claim 5 is characterized in that: when adopting by overfall aperture control beating pressure, be full of slurry in the pressure-stabilizing tower, the size of regulating spillway discharge by the aperture of regulating flow spill valve is controlled the pressure of slurry in the pressure-stabilizing tower.

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