RU2016849C1 - Settling tank - Google Patents

Abstract

FIELD: purifying of natural and waste water. SUBSTANCE: waste water is supplied to vessel 1 and passed lengthwise to conduit 3 mounted to discharge the purified water. Suspended impurities sink to the bottom of the vessel. The resulting deposit is removed to pit 5 with the waste water delivered by drain conduit 6. To be forced to the latter by pump 11 the water is withdrawn from vessel 1 and passed through pipeline 8 with nozzles 9 disposed on a higher level along the above-mentioned drain conduit 6. EFFECT: higher efficiency, improved quality of purified water, low power consumption. 2 dwg

Description

 The invention relates to the field of purification of liquids by sedimentation and can be used for the purification of natural and waste waters.

 Known sump containing a housing with a pit, supply and discharge pipelines, located at the bottom of the sump pipe to flush sediment and drive it to the pit and a hydraulic elevator to remove sediment [1].

 A disadvantage of the known sedimentation tank is the low efficiency of its work on flushing and removing sludge. This is due to the fact that sludge washing requires the supply of a large flow rate of liquid, which is necessary for the formation of a moving stream in the zone of placement of the flushing pipe along the entire length of the sump, which requires an additional tank with an appropriate amount of liquid and a pumping unit of the corresponding capacity. In addition, the supply of a large flow rate of liquid for washing off the sludge leads to a sharp increase in the moisture content of the sludge and an increase in its volume.

 Closest to the proposed technical essence and the achieved effect is a device containing a housing, nodes for supplying and discharging liquid and a means for removing sludge, including a flush pipe [2]. The sediment collected using the flush pipe in the pit is removed from it by a hydraulic elevator.

 The purpose of the invention is improving work efficiency.

 To this end, a sump containing a housing, nodes for supplying and discharging liquid and a means for removing sludge, according to the invention and in contrast to the prototype, is equipped with an additional pipe with holes for draining the liquid, placed along the wash pipe and above it and connected to the latter through a pumping unit.

 In FIG. 1 shows a sump, a longitudinal section; in FIG. 2 is a section AA in FIG. 1.

 The sump contains a housing 1, to which a pipe 2 for supplying the source fluid and a pipe 3 for discharging the settled fluid are connected. In the lower part of the housing 1 along its length there is a tray 4, made with a slope to the pit 5 located in the sump from the input side of the source fluid. A pipe 6 is placed in the tray 4 for flushing the sediment to the pit 5. The pipe 6 is made with holes along its length, to which nozzles can be attached.

 With a significant width in the sump along its side walls can be placed pipelines 7 with holes for flushing sediment to the tray 4. Along the pipe 6 above it is an additional pipe 8 with holes for collecting fluid from the sump. The holes are equipped with nozzles 9, which are expedient to place directed away from the pit.

 The pipe 8 through the suction pipe 10, the pump 11 and the pressure pipe 12 is connected to the pipe 6.

 In priyamke 5 posted hydroelevator 13 to remove sediment.

 The sump works as follows.

 Sewage liquid is piped 2 to the cavity of the housing 1 of the sump, is distributed over its cross section and flows at a low speed along its length towards the outlet of the sump. As a result, suspended solids contained in the wastewater settle to the bottom of the sump and into the pit 5. Sludge clarified wastewater is discharged through pipe 3 outside the sump.

 After sedimentation of the wastewater with the accumulation of suspended solids, they are removed from the sump. For this, the flow of waste fluid into the housing 1 of the sump is stopped.

 Suspended substances deposited on the bottom of the sump, by means of waste fluid coming from the flush pipe 6, are transported along the tray 4 to the pit 5 and then using the hydraulic elevator 13 are removed outside the sump. To generate a steady flow of wastewater through the tray 4 with the required speed, the wastewater is supplied to the flush pipe 6 by a pump 11 by taking the wastewater from the sump through a pipe 8 with nozzles 9. As a result, a flow of wastewater is formed in the zone of the flush pipe 6, moved to the side of the pit 5, which, together with the waste fluid entering the sump through the flushing pipe 6, creates a steady flow of waste fluid in the tray 4, ayuscheysya together with the suspended solids have settled to the pit 5, hydro elevator 13 from which the precipitate is removed outside of the settler.

 Removing sludge from the sump of the sump can be carried out in other ways, for example, using a plunger pump or through a pipeline under hydrostatic pressure.

 After removal of sediment, the sump settles back to work in the settling mode, for which the gate (valve) on the supply pipe opens.

 The presence of an additional pipeline with openings for draining fluid from the sump forms a flow of wastewater in the zone where the flush pipe is installed, moving towards the sump, and the skew is intensive over the entire length of the sump, to the sump of dirt that has settled on the bottom. This eliminates the flow into the sump of an additional amount of liquid for flushing the sludge, since for this purpose, due to the connection of the additional and flushing pipelines, liquid is used from the volume of the sump with a significant amount of sludge, which in turn significantly prevents the increase in moisture of the removed sludge and its increase volume.

 Compared with the known device, the proposed sedimentation tank does not require an additional tank with a supply of water for washing off the sediment, the volume is reduced 1.8-2 times due to a decrease in its moisture content.

(0.7l+0.17)=10

(0.7·0.1+0.17)=0.63 см/с$ где dэкв - эквивалентный диаметр зерен песка (0,05 см);
μ - динамический коэффициент вязкости (0,0084 г/см с).So, the flow rate of water for washing off the sludge in a known device (sump) with a section width B = 6.0 m and a sump length L = 42.0 m will be:
q = V ˙ B ˙ L = 0.0063 ˙ 6 ˙ 42 = 1.58 m ³ / s, where V is the ascending wash water velocity, m / s;
B is the width of the section of the sump, m (6.9);
L - sump length, m (42.0)
V = 10

(0.7l + 0.17) = 10

(0.7 · 0.1 + 0.17) = 0.63 cm / s $ where deq is the equivalent diameter of sand grains (0.05 cm);
μ is the dynamic coefficient of viscosity (0.0084 g / cm s).

=

= 420 c
Количество воды, необходимое для смыва осадка в одной секции отстойника, составит:
Q=q T_c=1,58 420=663 м³
При слое осадка в отстойнике h_ос=0,2 м, количество секций n=4 шт., периодичности смыва осадка Т_ос=5 сут общий объем осадка составит:
V $\genfrac{}{}{0ex}{}{\text{об}}{\text{ос}}$ ^щ=(B·L·h_ос+Q)·n·

=(6·42·0.2+663)·4

= 208312 м³
При использовании предложенного отстойника и подаче воды для смыва осадка с расходом q скорость перемещения смывного потока составит:
V¹ _п=2 ˙ V_п=2˙ 0,1=0,2 м/с
Время смыва осадка составит:
T $\genfrac{}{}{0ex}{}{\text{I}}{\text{с}}$ =

=

= 210c
Количество воды, необходимое для смыва осадка одной секции отстойника, составит:
Q¹=q T¹ _c=1,58 ˙ 210=332 м³
При слое осадка в отстойнике h_ос=0,2 м, количестве секций n=4 шт., периодичности смыва осадка Т_ос=5 сут общий объем осадка, удаляемого из отстойника за 1 год, равен:
V $\genfrac{}{}{0ex}{}{\text{1}}{\text{о}}$ _с=(B·L·h_ос+Q¹)·n·

=(6·42·0.2+332)·4·

= 111660,8 м³
Сравнение показывает, что при использовании предложенного отстойника объем осадка за счет снижения его влажности сокращается в 1,9 раза.With an average velocity of movement of the sludge flow in the sump, V _p = 0.1 m / s, the sediment wash time
T _c =

=

= 420 s
The amount of water required to flush the sediment in one section of the sump will be:
Q = q T _c = 1.58 420 = 663 m ³
When the sediment layer in the sump h _OS = 0.2 m, the number of sections n = 4 pcs., The sediment flushing frequency T _OS = 5 days, the total sediment volume will be:
V $\genfrac{}{}{0ex}{}{\text{about}}{\text{os}}$ ^u = (B · L · h _oc + Q) · n ·

= (6 · 42 · 0.2 + 663) · 4

= 208312 m ³
When using the proposed sedimentation tank and water supply for flushing sediment with a flow rate q, the velocity of movement of the flushing stream will be:
V ¹ _p = 2 ˙ V _p = 2˙ 0.1 = 0.2 m / s
The sediment flush time will be:
T $\genfrac{}{}{0ex}{}{\text{I}}{\text{with}}$ =

=

= 210c
The amount of water required to flush the sediment of one section of the sump will be:
Q ¹ = q T ¹ _c = 1.58 ˙ 210 = 332 m ³
. When a layer of sludge in the decanter h _a = 0.2 m, the number of sections n = 4 pieces, flush sediment periodicity T _a = 5 days total volume of sludge removed from the settling tank for 1 year, equal to:
V $\genfrac{}{}{0ex}{}{\text{1}}{\text{about}}$ _a = (B · L · h _oc + Q ¹⁾ · n ·

= (6 · 42 · 0.2 + 332) · 4 ·

= 111660.8 m ³
The comparison shows that when using the proposed sedimentation tank, the volume of sediment due to the reduction of its moisture content is reduced by 1.9 times.

Claims (1)

 A sump containing a casing, fluid inlet and outlet assemblies, and sediment removal means, including a flush pipe, characterized in that, in order to increase work efficiency, it is provided with an additional pipe with fluid drain holes located along and above the flush pipe and connected to last through the pump unit.

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