NL8003139A - AUTOMATED LIQUID SUPPLY SYSTEM. - Google Patents

Description

i ΥΟ 5Sb

Automated liquid supply system.

The invention relates to an automated liquid supply system comprising two or more low or underground atmospheric ventilating liquid storage vessels; at least one self-priming liquid transport pump; pipes connecting the storage vessels via the transport pump to one or more liquid collection points as well as means for the automated control, control and influencing of the liquid flow.

Such a liquid supply system is known in practice in a wide variety of applications, for example in the context of large volumes of solvent-consuming and processing processes or liquid fuel-requiring processes for heating purposes, in particular in those cases where the liquid has to be metered at the liquid collection points. The switch of the self-priming transport pump from an empty to a full storage vessel constitutes a critical moment because the liquid flow is then interrupted and vapor will first be drawn in and pumped prior to the supply of liquid from the full storage vessel. A practically applied solution to the sketched problem of ensuring an uninterrupted liquid supply, even when switching from an empty to a full storage vessel, concerns the placement of the transport pump or pumps next to the storage vessels in a pumping station. Since the storage vessels are normally located outside the commercial buildings, this solution has the disadvantage that the maintenance of the pumps is made more difficult because it often has to be carried out in wind and weather. Other disadvantages are that such a pumping station is a place with a high hazard class; the settings of the storage vessels and the pump foundations are difficult to keep the same unless the pumps are mounted on the storage vessels; with 5 pump leaks, the lining of the storage vessels is endangered by attack by the leaking liquid and there is also a risk of adversely affecting the cathodic protection often applied. In addition, the control systems for the pumps must also be extended to the storage vessel location and observation of the pumps by means of a closed TV circuit from a central control room is also made more difficult.

The object of the invention is an automated liquid supply system, in which the drawbacks associated with the known system 15 are eliminated, or at least the influence thereof is reduced considerably.

According to the invention there is provided for this purpose an automated liquid supply system of the type mentioned in the preamble, characterized in that the discharge pipe of the transport pump is branched at a branch point in a transport pipe leading to the liquid collection points and a pipe in which as close as possible after the branch point a regulator suitable for pressure control is included in the system; a buffer vessel is included in the supply line and the branching point is situated at a height sufficient for placing the buffer vessel underneath and making liquid available in the buffer vessel inflowable with a slope.

The automated liquid supply system according to the invention is suitable for use with a variety of liquids, for example liquid fuel, such as heating oils or solvents. In addition, the supply system according to the invention also lends itself to be designed in such a way, 8003139 & V -3-, that in this way an essentially completely closed system is obtained, with which a liquid can be supplied to one or more of the liquid collection points, wherein each offtake point can be recorded in a separately determined quantity, and 5 where no flow takes place to and from the relevant point in the case of zero offtake. In the event that all the take-off points have zero decrease, it must therefore be possible for all the pumped liquid to be fed through the said control element into the discharge pipe.

The invention is explained in more detail with reference to the drawing, which schematically shows a supply system according to the invention.

Figures 21 and 22 schematically show the two suction lines, each of which is connected to a different storage vessel, not shown in more detail. These storage vessels can, for example, have an open connection to the atmosphere, so not be under overpressure.

*

The self-priming transport pump 3 sucks liquid from the storage tank connected to it via one of the suction lines 21 or 22, for example suction line 22, where the other suction lines may be blocked, and pumps the liquid via the pressure line U to a higher level - in the drawing highest level, at which level the pressure pipe branches off into branching point 5 into two pipes 8 and 8 ', respectively. Coming back to the further course of the liquid later, for further explanation of the system below the level of branch point 5, the supply line 8 is connected to a buffer vessel 6, to which further transport line 16 is connected, which, branching, finally leads to the liquid collection points. k2, ^ 3 and kk. Immediately after, at least as close as possible to branch point 5 », an overflow valve 7, known per se, is included in the pipe 8, and it is usable for pressure control in the entire system. After the overflow valve 7, the line 8 * 'is connected to the return line to which the separate return lines 9, 9 "and 9, f" of the take-off points are also connected, which return line 9 »branches in line.

35 things 31 and 32, again connects to the liquid storage vessels.

8003139

«W V

-L_

All pipes are sloped from branch point 5 onwards.

As long as a storage vessel still contains sufficient liquid, a continuous flow of liquid is pumped by means of the pump 3 through the pressure pipe k, which flows at branch point 5 via the pipe 8 to and in the buffer tank 6 and from there further via the transport pipe 16 to the collection points 1 + 2, 1 + 3 and kk.

The fluid supply system as shown in the drawing naturally contains the required control elements (not shown in more detail) with which the final fluid supply at the take-off points 1 + 2, 1 + 3 and kk is fully automated. These control members, cooperating within a complete control system, therefore, for example, ensure the selection of the suction lines 21 or 22 and a switch to the other suction line as soon as the storage vessel connected thereto is empty, respectively, the selection of the return lines 31 or 32 for connection to the associated Storage containers in which they are included are not included in the invention.

As soon as a storage vessel is empty, the control system ensures automatic switchover to another vessel and the transport pump 3 is connected to the vessel connected thereto via the other of the suction lines 21 or 22. In the initial phase after the switchover, a quantity of vapor will first be drawn in by pump 3 and pumped via the pressure pipe 1+. The arrangement of the overflow valve 7 is such that the vapor arriving at the branch point 5 is passed through the overflow valve 7 and via line 8 'to the overflow valve 7, the discharge line 8. after the relief valve, the common return line 9 and one of the return line 31 or 32 are discharged to a storage vessel. As long as vapor passes the branch point 5, the liquid supply to the liquid take-off points is maintained from the amount of liquid available in the buffer vessel 6.

The buffer vessel 6 can also be in the form of an oversized pipe. It is only necessary to ensure a sufficiently large volume such that with the amount of liquid available in the buffer vessel the supply of liquid to the liquid collection points can be bridged. The volume is determined by the volume of the suction line, the capacity of the transport pump 3, the pressure in the discharge line and the maximum 5 expected drop at the liquid take-off points b2, b3 and V +.

The surplus liquid at the liquid collection points U2, h3 and flows back via the lines 9'j 9M and 9'11 and the final discharge lines 31 or 32 to one of the storage vessels.

The parts 3, b, 5, 6, 7, 5, 8, 8 ', 11, 16 form the pressure part of the system, the rest the pressure-free part. The necessary operating pressures for the liquid are realized in the extraction points and can differ per extraction point. When zero is taken in a take-off point, the flow is blocked. The overflow valve 7 must therefore be able to handle the full capacity of the pump.

It should be noted that foot valves need not be mounted in the suction lines nor in the return line system to the storage vessels. However, if the transport pump 3 is of the rotary type, a non-return valve 11 must be included in the discharge pipe.

The liquid supply system as shown in the drawing may be installed in a building while the storage vessels are arranged more or less far away from it outside the building, for example underground. Such a situation is found in particular in the case of flammable liquids.

Of course, modifications can be made to the automated liquid supply system as discussed above and shown in the drawing without leaving the scope of the invention. For example, it is possible to use two or more transport pumps.

· 'Λ. \ \ ÖCKÖ 3139

Claims (5)

Automated liquid supply system, comprising two or more low or underground atmospheric venting liquid storage vessels; at least one self-priming transport pump for the liquid; conduits 5 which connect the storage vessels, via the transport pump, with one or more liquid take-off points as well as means for the automated control, control and influencing of the liquid flow, characterized in that the discharge pipe of the transport pump is branched at a branch point in one to. A supply line leading to the liquid collection points and a discharge line in which a regulator suitable for pressure control is incorporated in the system as close as possible after the branching point; a buffer vessel is included in the supply line and the branching point is located at a height sufficient to place the buffer vessel below it to make the liquid available in the buffer vessel flowable under a slope to the liquid collection points. System according to claim 1, characterized in that the discharge pipe is designed as a return pipe leading to the storage vessels. System as claimed in claim 1, characterized in that the liquid collection points are also provided with return lines leading to the storage vessels. System according to claims 2-3, characterized in that the return lines are combined into a coherent and cooperating return line system. 5. System as claimed in claims 2-k, characterized in that the individual return lines are connected to the common return line at a point above the take-off points. 8003139 ^ 8 'i 8 "^ 7 J" \ X i - r16-, ^ w:,}, iv 31 / n "16- - n" "16—. 16-" 9 I 9 4 lil 42 43 44 2 £ 11 22 ^: p £ 21 80 0 3 1 3 9 Klaas Willem Sluiman