BRPI0803419A2 - plant for electricity generation and / or desalination by current hydraulic turbines - Google Patents

Abstract

The proposed innovation describes a plant for the production of electricity and desalination using submerged turbines and other equipment. In desalination operations, the plant does not use electricity. The plant can operate in rivers or in the ocean. In both rivers and the ocean, the plant can operate with turbines fixed to the bed or attached to a floating and anchored structure. In rivers, electricity generation and desalination equipment are installed on one of the banks. In the ocean, this equipment is installed above water level on a platform that is fixed at the bottom of the sea to ocean depths of up to 50 meters. For ocean depths greater than 50 meters, this equipment is installed on a semi-submersible platform anchored to the seabed. In these two configurations the turbines can be attached to another floating structure, also anchored to the seabed. In all plant installation modalities, turbines are interconnected to electricity generation and / or desalination equipment through rigid or flexible piping. The plant can be installed for operation in three modes: 1-Electricity generation. 2-Desalination. 3-Electricity Generation and Desalination.

Description

PLANT FOR GENERATION OF ELECTRICITY AND / OR DESALINIZATION BY CURRENT HYDRAULIC TURBINES

Technical Field

The present invention relates to a plant containing hydrokinetic-type submerged turbines for the generation of electricity and / or water desalination by reverse osmosis by the energy from the action of marine currents, tides and rivers. In desalination operations, the plant does not use electricity. The plant can be commutative and can operate for both desalination and electricity generation. The plant is basically composed of three main systems: submerged pumping turbines, external high pressure system, electricity generation group and / or desalination system. Each submerged turbine consists of a hydraulic pump and a set of directional valves. The external (high pressure out of water) system consists of hyperbaric chamber and hydropneumatic accumulator. The generation group consists of the turbine, electric generator and plant control module. The plant may contain several interconnected turbines supported on the bottom or seabed. The efficiency of turbines operating at different current speeds is maintained by varying the blade angle, the mechanism of which is controlled by dedicated software. The turbines contain automatic devices for operation in any direction of the current. Plant power or desalinated water flow can be increased by increasing the number of interconnected turbines.

Previous Techniques

There are several existing technical processes for water desalination. Among them the best known are: distillation, reverse osmosis and electric dialysis. In general, all these processes require expensive energy consumption.

Water desalination using sea probes as a source of energy already has several patent applications, but reverse osmosis desalination using river or ocean currents as a source of energy is still widespread. To date, no patent registrations have been found with the technical characteristics presented in the present invention.

Summary of the Invention

The present invention relates to a plant for operation with hydrokinetic submerged turbines in rivers or at sea whose operation principle enables both the generation of electricity and the desalination of seawater, brackish water, wastewater treatment of industrial or domestic origin. The plant operates through submerged turbines with bases resting on the riverbed or the seabed. The high turbine body with the water surface is optimized for higher current speeds without impairing navigation. In deep river or sea regions where there is no conflict with navigation, another way is to keep the turbines suspended, fixed to the underside of a floating structure anchored at the bottom of the ocean or at the bottom / shores when installation occurs on rivers. The equipment for generating electricity and / or desalination is installed on the dry bank when rushing rivers, or on a fixed platform at the bottom when it comes to the sea. These different types present the equipment for generating electricity and desalination always out of the water. in a dry place for ease of operation and maintenance. In desalination the process used is called reverse osmosis. The energy required to obtain the high pressure required in this process (900 psi) is provided by the action arising from marine, tidal and river flows. Thus, water desalination occurs without the use of electricity, significantly reducing the final cost of drinking water. Drinking water may be used for both domestic use and irrigation of agricultural land. An additional advantage is that this irrigation can be carried out at distances of hundreds of kilometers, since the plant can provide hydraulic energy superior to that required by the desalination process.

The plant consists of three main systems: submersible pumping turbines, external high pressure system, electricity generation group and / or desalination unit. Thus, a plant can also operate commutatively, generating electricity in one time period and desalination in another period.

Description of Operating, Plant and Equipment Modalities

The plant can be installed for operation in three modes:

1- First modality: Electricity generation.

2- Second mode: Desalination of seawater, brackish water or industrial or domestic wastewater.

3- Third mode: Electricity Generation and Desalination.

In the first mode the plant operates in closed circuit. Pump inlets and outlets of the various turbines are connected to two main ducts, one for suction and the other for discharge respectively. In this embodiment, the recirculating fluid may be water or any other. The suction duct feeds the various turbines with the circulating fluid contained in a reservoir. This reservoir together with a hydropneumatic accumulator, a hyperbaric chamber and the generator set are located on the river bank soil. If this plant is to be installed in the Ocean, this equipment is mounted above sea level on a floating platform anchored to the bottom or a fixed platform on the seabed:

Mechanical energy from asturine-driven currents pressurizes the fluid in the hydropneumatic accumulator. The pressurized fluid is released through a controlled valve, driving a turbine or a hydraulic motor, which coupled to a generator, produces electricity. The hyperbaric chamber is connected to the hydropneumatic accumulator and contains nitrogen or carbon dioxide and acts as a lung, contributing to the stabilization of pressure. In the case of sensible current reversal, a directional valve automatically reverses the flow direction in the hydraulic circuit, keeping the electricity generation regularized.

In the second mode aimed at desalination, the plant operates open circuit. The pump inlets of the various turbines are connected to the main suction duct that leads to the water to be desalted. The water to be desalinated should be collected from far away from the shore to minimize the presence of hydrocarbon contaminants such as oils, greases and kerosene. In the turbine pumps water is pressurized and sent to a line of filters of different porosities arranged in series belonging to the desalination unit. As it passes through the filters, water ready for desalination is deposited in a reservoir. From this reservoir water again feeds the turbine pumps in another circuit and the pressure is now raised to a level of up to 900 psi (61 bar) for desalination to occur at the usual flow rates. Water at this pressure is delivered to the facility cartridges containing reverse demosmos membranes. After passing through these membranes the desalinated water is led to a second reservoir. Wastewater with higher degree of desalinity is carried to a region far from the bank and the catchment point, where there is a current for salinity dissipation to minimize risks to the river or marine environment.

In the third mode the plant is commutative. The facility applies to both electricity generation and desalination operating at different times. This plant works in an open circuit and the water used to meet either of the two purposes is captured in the same way described in the second mode (desalination). A commutating valve is responsible for directing water to serve one or another purpose. During operation of the first mode, that is, electricity generation, the water is returned to the river or to the sea, near the plant, without any mixture or addition of pollutants.

The plant's external high-pressure system is terrafirmed and consists of a hyperbaric chamber and hydropneumatic accumulator. The generation group consists of a turbine, electric generator, plant control module and / or a desalination unit. The plant may contain several interconnected turbines supported at the bottom of the river or seabed at a height suitable for harnessing the current without impairing navigation and turbine integrity. The efficiency of turbines operating at various current speeds is maintained by varying the blade angle, the mechanism of which is controlled by dedicated software. The turbines contain automatic steering devices for operation in any current direction. The power of the plant or the desalinated water flow can be increased by increasing the number of interconnected turbines. The proposed innovation concerns a plant for the generation of electricity by the action of marine currents, tides and rivers. The plant consists of three main systems: submerged pumping turbines, external high pressure system and electricity generation group and / or desalination unit. Turbines positioned on the seabed or river at a convenient height have devices that allow them to be oriented according to the current direction to maintain the highest yields. Turbines also operate with reverse current flow that is common in river mouths. Maintenance of turbine efficiency operating at various current speeds is accomplished by varying the blade angle, controlled by dedicated software. Each turbine has its shaft connected to a hydraulic pump for the conversion of mechanical energy to hydraulic energy.

At the power plant, the turbines pick up the waterpipe (or other fluid) from a low-pressure reservoir located on river bank soil or on a platform if the installation is at sea. The fluid is pressurized by the pumps into a hydropneumatic accumulator.

This accumulator releases the fluid at high pressure to drive a turbine (or hydraulic motor) coupled to a generator to produce electricity. After leaving the generation system, the fluid returns to the low pressure reservoir featuring closed loop operation. Fluid conduction between the immersed turbines and the external electricity generation system is by rigid or flexible low and high pressure piping.

High pressure and electricity generation systems are installed on the river bank or above sea level and can be fixed or floating. These systems consist of hyperbaric chamber, hydropneumatic accumulator and generation group. The generation group is composed of turbine, electric generator and plant control module. The plant can contain several interconnected turbines supported on the riverbed or seabed. Turbines contain automatic steering devices for operation in any direction of the current. The power of the plant can be increased by increasing the number of interconnected turbines.

Turbines are designed to drive pumps in a wide pressure range, up to 3,000 psi (204 bar).

Description of Modes of Operation, Plant and Equipment

The plant operates through the action of river or sea currents, driving the blades of submerged hydraulic turbines supported and anchored in the bottom. These turbines contain hydraulic pumps connected to the mainshaft that constitute the pumping mechanism. This mechanism captures water from the river or sea and raises its pressure to levels suitable for desalination or electricity generation by sending it to a hydropneumatic accumulator. This accumulator is connected to the hyperbaric chamber and works like a lung and is responsible for stabilizing depression. High-pressure pumped water is released from the hydropneumatic accumulator via a flow control valve to move a turbine or hydraulic motor. The rotation of the turbine shaft or hydraulic motor is transmitted to a coupled electric generator to convert mechanical energy into electricity. The flow control valve releases the jet through an electronic control keeping the speed in the rotation of the turbine or the hydraulic motor constant. This valve operates at pressures up to 3,000psi (204 bar). In desalination operations, a commutator valve redirects water at high pressure by disconnecting the electricity generation group and connecting a desalination plant.

Operational Processes for Electricity Generation

The power of the plant in kW (at the water jet outlet) is given by the flow product (m3 / s) at the jet outlet and the pressure (m.c.a.) supplied by the hydropneumatic accumulator during operation. This pressure in a conventional hydroelectric plant is provided by the height of the waterfall (potential energy). The plant of the present invention mentioned in the "First Mode" for Electricity Generation, operates in a closed loop, pumping water from a reservoir (located on land on rivers or on a platform in the case of the ocean) to the hydraulic accumulator. The flow of water in the hydraulic accumulator pumped from the turbines must be equal to or greater than that released by the jet to move the turbine (or hydraulic pump). This volume of water supplied to the accumulator from the pumping modules keeps the system pressure constant through a pressure regulating valve. A soft-operated valve controls the output flow by monitoring the genset rotation according to the requested electrical load while maintaining the recommended electrical voltage and frequency.

Reverse Osmosis Desalination Operational Processes

The power extracted from the current of rivers or oceans is given by the formula P = p.A.v7,12 where:

P is the extracted power, p is the water density, A is the internal diameter area of the turbine, and v is the current velocity.

The hydraulic energy of the current is converted by the submerged turbines into mechanical energy. This mechanical energy drives a different-stage hydraulic pump coupled to the turbine shaft. The pump captures saltwater by raising its pressure in a first stage to the filtration pressure (45 psi or 3 bar). Water is piped to the desalination unit for the initial filtration operation. This desalination unit is located at the riverbed or above water level if the facility is at sea. After filtration the water returns to the turbine to raise its pressure in a second stage to the desalination pressure (900 psi or 61 bar). High pressure water is again led through ducts to the desalination plant. At the desalination plant part of the water under high pressure (approximately 50%) catwalks reverse osmosis cartridges becoming quality drinking water for human consumption. The volume of non-desalinated water is the tailings. This tailings are disposed of by pumping in a third stage to disperse in distant currents.

Description of the Figures

Figure 1 presents the simplified scheme of the set of equipments that make up a desalination plant without the use of electricity. The set consists basically of two distinct units: the conventional reverse osmosis membrane desalination module and the turbine pumping system which consists of converting the energy contained in the currents to the movement of the pumps. In the scheme, the letter A represents the turbine supported on the river or ocean floor. The letter B, Pumpkin responsible for increasing water pressure. The letter C means the inlet filter fitted with a check valve at the suction inlet of the pump. The letter D represents the support base of the turbine. The letter E represents river or ocean oil. The letter F represents the pipeline containing the interconnection lines between the turbines and the desalination plant. V1represents the low pressure accumulator inlet valve. The letter G, low pressure accumulator. The letter H, the first filter with 75 micron porosity. The letter I, the second filter with 25 micron porosity. The letter J; the last 5 micron porosity filter.

The letter K represents the first reservoir of the circuit, and is used for storing filtered water. The letter L represents the high pressure line. V2 represents the high pressure accumulator inlet valve. The letter M, the accumulator of the high pressure line of the hydraulic circuit.

The letter N represents the set of membrane cartridges for reverse osmosis adalinization. V3 represents the pressure regulating valve at the outlet of the desalinated water line. The letter O represents the desalinated water reservoir and the letter P represents the water-discharge outlet line with the highest salinity concentration.

Figure 2 shows the scheme a plant installed in a river.

In this scheme the turbines are fixed on metal or concrete bases and anchored in the riverbed. Electricity generation and / or desalination equipment is installed on one of the river banks on dry land. Rigid or flexible tubing deposited and fixed in the riverbed connects the turbine assembly to the onshore installations.

In this scheme, the letter A represents the riverbed. The letter Bre represents one of the turbines installed at the bottom of the river. The letter C represents the piping connecting the turbine assembly to the onshore installations. The letter D represents the soil on dry land of one of the banks of the river. The letter E represents the facilities for the generation of electricity and / or desalination positioned on the river bank. Figure 3 shows the scheme of a plant also installed on a river, differing in the way the turbines are fixed. In this scheme asturbines are fixed hanging underneath a floating norio structure. This structure can be anchored to the bottom as well as a combination using the bottom and one or both margins. In this scheme, the letter Are represents the floating structure on the river. The letter B represents one of the fixed turbines hanging underneath the floating structure. The letter C represents the piping connecting the turbine assembly to the onshore installations. The letter D represents the solid soil of one of the river banks. The letter Erepresents the facilities for the generation of electricity and / or desalination. The letter F represents the water level of the river. The letter G represents riverbed.

Figure 4 shows the scheme of a plant installed in the seawater, with a depth of up to fifty meters. In this plant the turbine bases are fixed in the seabed. The height of the bases will define the position of operation of the turbines in relation to the current speed and the sea level.

Electricity generation and / or desalination equipment is installed on the upper base of a fixed platform on the seabed. This platform bears some resemblance to those used in the jacket-type oil drilling and extraction area.

In this scheme, the letter A represents the upper base of the platform for the installation of equipment. The letter B represents equipment for electricity generation and / or desalination. The letter Cre represents one of the turbines positioned on the seabed. The letter D represents the pipe that connects the turbine assembly to the equipment installed on the platform.

Figure 5 shows a schematic of a plant installed in the seawater, with a depth of more than fifty meters. In this plant, turbine bases are also fixed in the seabed. Likewise, the height of the bases defines the operating position of the turbines in relation to the current speed and sea level, safeguarding the minimum draft required for navigation. This platform bears some resemblance to those used in the semi-submersible oil field.

In this scheme, the letter A represents the base of the platform intended for equipment installation. The letter B represents equipment for electricity generation and / or desalination. The letter C represents one of the turbines positioned on the seabed. The letter D represents the piping that connects the turbine assembly to the equipment installed on the platform. The letter E represents one of the tethers for anchoring the platform to the seabed. The letter F represents the seabed. Figure 6 shows the scheme of a plant installed in the sea in deep waters also exceeding fifty meters. In this plant, the turbines are fixed in a floating structure in the sea. The dasturbine operating position is 2 to 5 meters below sea level.

In this scheme, the letter A represents the base of the platform intended for equipment installation. The letter B represents equipment for electricity generation and / or desalination. The letter C represents the floating structure. The letter D represents one of the turbines positioned in the seabed. The letter E represents one of the moorings for anchoring the floating structure of the turbines in the seabed. The letter F represents one of the tethers for anchoring the platform to the seabed. The letter Gre represents the pipe that connects the turbine assembly to the equipment installed on the platform. The letter H represents the seabed.

Plant Advantages for Electricity Generation and / or Desalination from Currents

- Production of clean and renewable energy with virtually no environmental impacts.

- Contribution to the existing power transmission network by adding one more source of electricity.

- Supply of electricity and or desalinated water in islands or places far from the coast where the electric transmission grid is non-existent.

- The installation of the turbines is modular enabling requiring low flows and high operating pressures, which means lower deployment and maintenance investment costs.

- The required final power determines the number of turbines to be installed.

- Possibility of installation in three different modes:

- First mode: Generation of electricity.

- Second mode: Desalination of seawater, brackish river or wastewater of industrial or domestic origin.

- Third mode: Electricity Generation and Desalination.

The equipment listed should not be considered as defining and / or limiting the scope of the present invention. The quantity, types and arrangement of such equipment may change according to the location and characteristics where the plant is installed.

Claims (23)

1.- ELECTRICITY GENERATION PLANT El Oudessalinization by Hydraulic Current Turbines, characterized by the use of submerged river hydrokinetic turbines with the electric generation equipment installed on firm ground in one of its margins. 2.- PLANT according to claim 1, characterized by the use of a hyperbaric chamber associated with a hydropneumatic accumulator for river electric generation, installed on firm ground in one of its margins. Plant according to claims 1 and 2, characterized by the use of equipment intended for river desalination, installed on firm ground on one of its banks. 4.- PLANT according to claims 1 and 2, characterized by the use of desalination and electricity generation equipment installed on firm ground on one of the river banks. Plant according to Claim 1, characterized in that it operates at pressures up to 3,000 psi. Plant according to any one of claims 1, 2, 3 and 4, characterized by the use of a floating structure in rivers to fix dasturbines. 7.- PLANT, characterized by the use of submerged and fixed hydrokinetic turbines on the seabed with the electric generation equipment installed on a fixed platform on the seabed. 8.- PLANT, characterized by the use of submerged and fixed hydrokinetic turbines in a floating structure at sea with electrical generation and / or desalination equipment installed on a semi-submersible platform also floating at sea. 9.- PLANT according to claim 7, characterized by the use of desalination equipment installed on a fixed platform at sea. 10.- PLANT according to claims 7 and 8, characterized by the use of desalination and electricity generation equipment installed on a fixed platform at sea. Plant according to claims 5, 7 and 8, characterized by the use of a hyperbaric chamber associated with a hydropneumatic accumulator for electric generation installed on a fixed nomar platform. Plant according to Claim 1, characterized by the use of a hydropneumatic accumulator associated with the desalination equipment installed on a fixed platform at sea. 13.- PLANT, characterized by the use of submerged hydrokinetic turbines at sea with the electric generation equipment installed on a floating platform at sea. Plant according to claim 12, characterized by the use of desalination equipment installed on a floating platform at sea. 15.- PLANT according to claims 12 and 13, characterized by the use of desalination and electricity generation equipment installed on a floating platform at sea. Plant according to claims 5, 12 and 13, characterized by the use of a hyperbaric chamber associated with a hydropneumatic accumulator for electric generation installed on a floating sea platform. Plant according to any one of claims 5, 12, 13 and 14, characterized by the use of a commutative valve for plantation operation for generating electricity and for desalination. Plant according to claim 1, characterized by operating with submerged turbines composed of hydraulic pumps and directional valves operating at pressures up to 3,000 psi. Plant according to claim 1, characterized in that it contains several interconnected turbines supported on the bottom of the river or seabed. 20.- PLANT, characterized in that it contains a mechanism for varying the angle of the turbine blades controlled by a dedicated software. 21.- PLANT, characterized by containing directional valves for operation in the opposite direction to the current in the rivers. 22.- PLANT, characterized in that it contains in the turbines steering and turning devices for operation in any direction current in the ocean. 23.- PLANT, characterized by installation capacity and operation in the modalities of electricity generation, water desalination and switching electricity generation for desalination.