WO2002014613A1

WO2002014613A1 - Kinmen type of integrated hydrologic circuits

Info

Publication number: WO2002014613A1
Application number: PCT/CH2000/000436
Authority: WO
Inventors: Kenneth Hsu
Original assignee: Fengshui Water Technology Ltd.
Priority date: 2000-08-17
Filing date: 2000-08-17
Publication date: 2002-02-21
Also published as: AU2000264220A1

Abstract

The integrated hydrologic circuit comprising at least one hydrologic cell having a pair of polarities as hydropotentials with a porous medium therebetween and having means for keeping the positive polarity high and means for keeping the negative polarity low by feeding respectively pumping out water to respectively from said polarities.

Description

Kinmen Type of Integrated Hydrologic Circuits

Various processes of constructing integrated hydrologic circuits (IHC) for underground water-storage in stream valley deposits have been developed by the patent owner. The present invention teaches the construction of the Kinmen Type of IHC which consists of one or more nests of hydro- logic cells, each having a pair of polarities as hydropotentials to induce hydrodynamic movement of the water in a porous medium between the positive and negative polarities of the IHC into a collector, from which water is collected and integrated into a distribution system.

Background of the invention

Description of prior developments

Hydrologic circuits consist at least of a storage, a con- duit for transport and filtering, and a collector as a sink of the circuit. Current hydrologic circuits are mostly reservoir lakes for water storage, canals for water transport and irrigation, and water-towers for distribution to consumers. They are inefficient circuits because of water-loss during storage and transport.

Previous developments taught the constructions of IHC (integrated hydrologic circuits) for water-transport and water-storage in porous medium. For this technique a number of patent applications have^' been filed, namely:

- US Patent Appln. 09/123 609, "Use of porous medium in an integrated hydrologic circuit for water storage and transport in land reclamation, agriculture and urban consumptions" , - US Patent Appln. 09/196 730, "Integrated hydrologic circuits" ,

- EU Patent Appln. 98/122099.9, "Storages, conductors, filters, and sterilizers in integrated hydrologic circuits",

- US Patent Appln. 09/299 574, "Integrated hydrologic circuits in valley-systems for water-supply, hydro- electricity and flood control".

Those developments taught the construction of IHC (integrated hydrologic circuits) to store, filter and/or steril- ize natural or treated waters. The IHC consists of individual or nests of hydrologic cells. Each hydrologic cell of an IHC circuit consist of a pair of hydropotentials which provides hydrodynamic driving force to move the water in the IHC, and a hydrocapacitor which provides capacity for water storage. The hydropotentials consist of a positive polarity where the hydrodynamic potential is high, and a negative polarity where the hydrodynamic potential is kept low when water is withdrawn from the IHC. The hydrocapacitor is commonly a porous medium in subsurface.

Field of invention

A shortcoming of the prior developments is its failure to keep the hydrodynamic potential of the positive polarity of a hydrologic cell at a constant height to maintain a hydro- dynamic gradient to supply ^"water at a constant rate to the collector (negative polarity) .

In previous constructions of hydrologic cells of IHC in valley systems, the natural groundwater table (G T) is the positive polarity, and the water-collector, commonly of the Helminthoid type, is the negative polarity. The G T in valley-deposits (which are the hydrocapactor) has been elevated through the construction of small dams or barriers across a stream. Since the GWT of the valley deposit will be lowered when water is pumped out of a hydrologic cell, there is a possibility when the GWT of the valley deposit (positive polarity) falls to or below that of the hydrodynamic potential of the collector (negative polarity) . At that stage the water in the cell is hydrostatic and no more water can be pumped out.

The present invention teaches the construction of hydro- logic circuits which remedy the shortcoming. The patent teaches the construction of hydropotentials which keeps the hydrologic potential of the positive polarity of a hydro- logic cell of an IHC always elevated even when water is being withdrawn from the cell. The maintenance of a high hydrodynamic potential of a positive polarity, such as the GWT in valley deposits, can be effected, for example, through the feeding of surface water from lakes, reser- voirs, rivers, etc., into a specially constructed device which serves as the positive polarity. This device provides the constantly elevated positive potential to induce hydro- dynamic movement of water to recharge the groundwater in the porous medium of a hydrologic cell and at the same time drives the water in the medium to the collector of the cell to be collected for consumption.

The potential gradient between the positive and the negative polarities of a hydrologic cell can then be adjusted through the elevation or sinking of the hydrodynamic poten- tial of the water-collector, which constitutes the negative potential of an IHC. A constant potential of the collector insures production of water at a constant rate as demanded by consumption.

Description of the drawings

Fig. 1 Horizontal section of a hydrologic cell, illustrating the positioning of the aquidykes (2) into which water is fed continuously from a surface source (4) to maintain the high polarity of the hydrodynamic potential of the positive polarity of an IHC and the central location of the collector

(6) . Water flows from the aquidykes through a porous medium (8) into the collector. The figure is drawn to a 1:2000 scale. Larger or smaller hydro- logic cells can be constructed according to the present invention;

Fig. 2 profile of an aquidyke, illustrating that water is fed into a perforated pipe (10) from which water is seeped into a trench filled with very porous and permeable gravels (12) . Water with a high hy- drodynamic potential is then slowly seeping into the porous medium (14) toward the collector. The figure is drawn to a 1:20 scale. Larger or smaller aquidykes can be constructed according to the present invention;

Fig. 3 profile of a part of a collector, illuminating that the collector consists of a layer of gravel (16) in a trench which is refilled with mud or other impermeable material (18) . The upper part of the wall (20) of the trench is water-tight, and the lower part is porous and permeable so that water can seep from the porous medium (14) through this part of the wall (22) into the gravel (16) . Embedded in the gravel (16) are perforated pipes (24) which are arranged in a fashion to permit a maximum surface contact between the pipes and the gravel. The figure is drawn to a 1:300 scale. Larger or smaller collectors can be constructed according to the present invention;

Fig. 4 profile of a part of the collector, illuminating that water from the perforated pipes (24) will gather and flow into a borehole (26) which penetrates into a depth greater than the bottom of the gravel layer (28) . Water is pumped out of the borehole to keep the hydrodynamic potential of the collector, i.e. the negative polarity of the IHC sufficiently low to provide a steep enough hydro- dynamic gradient to deliver the prescribed amount of water needed for daily consumption. The figure is drawn to a 1:100 scale. Larger or smaller boreholes can be constructed according to the present invention.

Description of the preferred embodiment

This invention teaches a process of constructing hydrologic circuits, mostly underground,^' for maintaining a hydrodynamic gradient sufficiently steep to permit the delivery of prescribed amount of water needed for daily consumption, and for storing sufficient volume of water underground during the wet months, in the form of recharged groundwater, to be exploited during the dry season. The Principles of the Kinmen Type of IHC

The concept of IHC is innovated to attain a balance of water-budget in water management. Instead of ad hoc arrangements to build individual reservoirs to supply local or re- gional needs or to build desalinisation plants, integrated hydrologic circuits are built to recharge and to exploit groundwater in a water-supply network. The management of water-supply from an IHC could then be patterned after that of electricity-supply, and be systematized with a computer system. Water from areas where water is stored during times of excess could supply the needy areas during times of deficiency.

An electric circuit has generators to generate electricity, batteries or capacitors to store electricity, conductors or resistors to transmit electricity under an electric potential. Water is "generated" by rainfall, and it could be stored in "batteries" or hydrocapacities (surface or underground reservoirs) , and be transported through a conductor (pipes) or transmitted across a resistor (porous medium) under a hydrodynamic potential, to be collected by collectors (wells, helminthoid collectors) and pumped up for consumption.

Rainfall is the source of freshwater. Water-supply cannot be so easily managed as electricity supply because the wa- ter-generators (rainfalls) work too erratically, especially in regions of seasonal precipitation. There is thus a need for storages to store-.the water "generated" (fallen) during wet seasons for use .during dry seasons . Electricity is stored in batteries or capacitors. Water is stored in surface and/or subsurface reservoirs. A surface- water body, natural or artificial lake behind a da , can store and discharge rapidly. On the other hand, there is the disadvantage of losses by evaporation, leaking, or pollution. Surface reservoirs are at best temporary storage, and water captured by such temporary storages should thus be rapidly transported into underground reservoirs for more long-term storage.

Stream deposits, consisting mainly of sands and gravels, are natural storage of water. Rainfall or surface water can seep into stream deposits in the form of groundwater recharge. The rate of recharge is, however, too slow, and much of excess rainfall will be carried to the oceans in the form of surface runoffs (sheet flows, rills, rivers, etc.). Without adequate recharge, the GWT (groundwater table) in a porous medium is lowered, especially in regions of extensive exploitation of groundwater. The recharge of groundwater is thus the first priority for maintaining a hydrologic balance. There are two problems: (a) a source of water, and (b) an adequate rate for recharging.

Where the drainage system is sufficiently integrated, large streams flow year-round, river water can be an adequate source for IHCs . The positive polarity of the aquidykes can be kept high by water flowing constantly through pipes into the perforated pipes of the^' aquidykes.

Where surface water i-s scarce and evaporative rate is high during dry seasons, surface reservoirs can rarely store sufficient rainwater fallen during wet seasons to feed the hydrologic cells of an IHC, because much of the water in surface water bodies is lost by evaporation, seepage, pollution etc. Surface reservoirs in more arid areas can only be temporary storages. When (during the dry season, for example) no surface source is available to recharge the groundwater of an IHC, the water stored in the IHC during the wet seasons will have to be exploited for consumption. Consequently the GWT of the water in the porous medium at the times of no recharge will fall . The volume of the water stored and made available for consumption is the difference between the maximum and the minimum GWT of the water in the porous medium of such an IHC.

Fengshui Aquidykes

An electric capacitor, such as a battery, is depleted after it delivers electrons to a collector. A hydrocapacitor is depleted after it delivers water to a collector. When water is pumped out of a well, the water in the porous medium is depleted, and the depletion causes a slowdown of flow rate. One kind of battery is, under normal circumstances, never depleted, and the automobile-battery belongs to that kind. Battery is discharging, and being charged at the same time. The IHCs of Kinmen type are an analogue of automobile batteries, they are charging and discharging at the same time.

The IHCs of Kinmen type consist of one or more nests of hydrologic cells. Each cell consists of aquidykes which are buried trenches of gravel enclosing perforated pipes (Figures 1 and 2) . Water from surface reservoirs flows readily into perforated pipes-.and seeps rapidly into the surrounding gravel . Continuous feeding of surface water permits the maintenance of the hydrodynamic potential at this positive polarity of the IHC to induce water flow from the aquidyke through the porous medium to the collectors.

Fengshui Collectors

Collectors are constructed to collect water flowing from the aquidykes through an intervening porous medium. For the Kinmen type of IHC, collectors are placed at or near the center of an area bounded by Fengshui Aquidykes (Fig. 1) . Water is pumped out of the collectors to maintain the hydrodynamic potential which induces the water movement .

Collectors for groundwater are commonly wells or boreholes. Special type of collectors has been designed and shown by Figure 3. The collector consists of a layer of gravel (16) in a trench which is refilled with mud or other impermeable material (18) . The upper part of the wall (20) of the trench is water-tight, and the lower part is porous and permeable so that water can seep from the porous medium (14) through this part of the wall (22) into the gravel (16) . Embedded in the gravel (16) are perforated pipes (24) which are arranged in a fashion to permit a maximum surface contact (26) between the pipes and the gravel.

Where the porous medium under the collector is not very permeable, boreholes can be drilled into the substratum under the collector. Those boreholes are to be refilled with gravels, and water collector from deeper horizons will flow into the layer of gravel of the collector.

In order to achieve more rapid flow rate from the gravel into the perforated ■pipes of a collector, those can be arranged in a helminthoid or similar fashion as described in our previous patents so that the contact area between a porous medium and perforated pipes is maximal. Water from a porous medium can thus flow into the pipes at an optimum rate.

The water flowed into the perforated pipes (24) will gather and flow into a hydropotential-regulating borehole (28) which penetrates into a depth greater than the bottom of the gravel layer (30) . Water is pumped out of the borehole to keep the hydrodynamic potential of the collector, i.e. the negative polarity of the IHC sufficiently low to provide a steep enough hydrodynamic gradient to deliver the prescribed amount of water needed for daily consumption.

Source of Surface Water for IHC

Perennial streams are good sources for IHC. Where precipi- tation does not fall regularly and the volume of stream discharge is too small to recharge the groundwater in IHC, water from precipitation and from runoffs has to be first stored temporarily. The temporary surface storages could be ponds and lakes, small surface reservoirs, etc. Water could be fed into the aquidykes of IHCs by flowing through pipes, as such an underground transmission will avoid evaporative loss, and a pressure-driven flow permits upward as well as downward movement of the water-flow.

Claims

1. Construction of an integrated hydrologic circuit IHC which consists of one or more nests of hydrologic cells, each having a pair of polarities as hydropotentials to in- duce a hydrodynamic movement of the water in a porous medium between the positive and negative polarities of the IHC, comprising means for keeping the positive polarity high by surface water fed into a device serving as the positive polarity and means for keeping the negative polar- ity low by pumping water out of a device serving as the negative polarity.

2. An IHC according to claim 1, wherein the device of a hydrologic cell of IHC serving as the positive polarity comprises aquidykes and the device serving as the negative polarity comprises a collector.

3. An IHC according to claim 1, wherein the source of water for the IHC is a river, a pond or lake, or an artificial water reservoir, or a combination thereof.

4. An IHC according to claims 1 and 2,,wherein the col- lector is buried sufficiently deep so that the hydrodynamic gradient between the aquidykes and the collector is sufficiently steep to induce hydrodynamic movement at a rate to satisfy demand.