Abstract:
An electrical generator converts the high blast pressures of explosives into useful electricity by capturing the explosive gases and using the high gas pressures to alternately push water hydraulically between two tanks and through water turbines connected to DC electric generators. Water expelled through a water turbine from one tank is used to fill the other tank. Batteries can be used to store the electrical energy generated, and inverters followed by transformers convert the DC electric from the turbine-generators to 110-VAC, 220-VAC, and 440-VAC. A microcomputer controller connected to various sensors and solenoid valves coordinates the timing and routing of the detonation of explosives, tank pressures, venting, valving, and load control.

Description:
RELATED APPLICATIONS 
     This Application claims benefit of U.S. Provisional Patent Application, A UNIQUE METHOD OF GENERATING ELECTRICITY USING EXPLOSIVE SUBSTANCES AS A POWER SOURCE, Ser. No. 61/100,915, filed Sep. 29, 2008. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to electrical power generation, and in particular to devices and methods for converting the gas pressure generated by explosives into electricity. 
     2. Description of the Prior Art 
     Useful electrical energy does not exist in nature and it must be converted from other available energy forms such as gasoline, diesel, coal, natural gas, geothermal, steam, hydro, solar, etc. Some of these energy sources are expensive, some are highly pollutant, some are difficult to convert efficiently, and some are not very portable as is needed in vehicles. 
     Explosives like gunpowder; Cordite, Ballistite, and Poudre-B smokeless powders; trinitrotoluene (TNT), Dynamite; nitroglycerin; Tovex and other water gel explosives; etc., release a lot of energy in a very rapid pulse. Explosives usually have less potential energy than petroleum fuels, but their high rate of energy release produces large blast pressures. TNT has a detonation velocity of 6,940 m/s compared to 1,680 m/s for the detonation of a pentane-air mixture, and the 0.34-m/s stoichiometric flame speed of gasoline combustion in air. Explosives are classified as “low” or “high” explosives according to their rates of decomposition. Gunpowder is a low explosive, while TNT is a high explosive. Low explosives burn rapidly or deflagrate, while high explosives detonate. 
     The energy released includes high levels of heat, light, and gas pressure. These are all quickly dissipated if not captured or otherwise contained. For example, at 15° C. the volume of gas produced by the explosive decomposition of one mole of nitroglycerin, becomes, V=(23.64 liter/mol)(7.25 mol)=171.4 liters. The molar volume of an ideal gas at 15° C. is about 23.64 liters. The potential of an explosive is the total work that can be performed by the gas generated by the explosion. If uncontained, it expands adiabatically from its original volume until its pressure is reduced to atmospheric pressure and its temperature to ambient. 
     In the nitroglycerin reaction, C 3 H 5 (NO 3 )3→3CO 2 +2.5H 2 O+1.5N 2 +0.25O 2 , the products are carbon dioxide, water, nitrogen, oxygen, and heat. Therefore, a relatively small solid or liquid volume is converted into a very large volume of relatively benign gases. Nitroglycerin explosions are relatively clean, compared to TNT which is poisonous and produces a lot of carbon soot in its reaction. 
     Firearms and artillery use the gas pressure generated by the detonation of smokeless powder to accelerate bullets and projectiles to very high muzzle velocities on the order of 2,000+ feet per second. Sticks of explosives are detonated in holes drilled into geologic deposits to fracture the ores and make removing the material as easy as scooping up the pieces. 
     What is needed is a device and method to convert explosive energy into a more useful form of electrical energy as used in homes and industry. 
     SUMMARY OF THE INVENTION 
     Briefly, an electrical generator embodiment of the present invention converts the high blast pressures of explosives into useful electricity by capturing the explosive gases and using the high gas pressures to alternately push water hydraulically between two tanks and through water turbines connected to DC electric generators. Water expelled through a water turbine from one tank is used to fill the other tank. Batteries can be used to store the electrical energy generated, and inverters followed by transformers convert the DC electric from the turbine-generators to 110-VAC, 220-VAC, and 440-VAC. A microcomputer controller connected to various sensors and solenoid valves coordinates the detonation of the explosives, tank pressures, venting, valving, and load control. 
     These and other objects and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiments which are illustrated in the various drawing figures. 
    
    
     
       IN THE DRAWINGS 
         FIG. 1  is a simplified functional block diagram of a single-stage electrical generator embodiment of the present invention that cycles pressurized water between two tanks and through two sets of water turbines; 
         FIG. 2  is a flowchart diagram of an electrical generator method embodiment of the present invention to cycle pressurized water between two tanks and two water turbines, as in  FIG. 1 ; 
         FIG. 3  is a functional block diagram of a single-stage electrical generator embodiment of the present invention that cycles pressurized water between two tanks and through two water turbines like that of  FIG. 1 , but that reduces duplication of the DC generators and inverters, and some of the valving; and 
         FIG. 4  is a simplified functional block diagram of a two-stage electrical generator embodiment of the present invention that uses explosive gases to pressurize water, and then uses pressurized hydraulics to spin electrical generators with hydraulic motors and turbines. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In  FIGS. 1-4  and the following text, some of the more conventional and routine elements commonly used with gas and hydraulic valves, pressure tanks, plumbing, and process control systems are not shown or described. For example, inspection ports and drains for water tanks, safety relief valves, check valves, nozzles for turbines, gearboxes and pulleys, wireless interfaces, wiring, etc. The components like these that should be used are engineering choices and are routinely stocked and installed by technicians. The critical and unusual combinations and their interrelationships are described here in detail. 
       FIG. 1  represents a single-stage electrical generator system embodiment of the present invention, and is referred to herein by the general reference numeral  100 . Generator system  100  produces electrical power suitable for homes, businesses, industry, and the utility grid from the explosive energy captured from cartridges  102  loaded in a magazine  104  and fired in a breach  106 . Cartridges  102  should include low explosives that burn clean and soot-free, and the chemical reactions should not produce any dangerous gases or byproducts. For example, nitroglycerin reactions only produce carbon dioxide, water, nitrogen, oxygen, and heat. The heat actually helps increase the gas pressures up to operating levels and should not be wasted or exhausted until the maximum in work has been extracted. 
     The heated gaseous explosive products are passed through a check valve  108  to a pressurized-gas tank  110 . A pressure safety valve (PSV)  112  provides relief if the internal pressures exceed a safe maximum. A pressure sensor (P)  114  measures the tank pressures for a microcomputer controller  120 . In some installations the pressure readings will be reported wirelessly, in others a simple 4-20 milliamp process control loop can be used. 
     Microcomputer controller  120  coordinates all the timing and valve control needed to operate generator system  100  and keep it safe. It uses readings from pressure sensor (P)  114  to determine when more cartridges  102  need to be loaded in magazine  104  and fired in breach  106 , and it controls the actual firing. Microcomputer controller  120  also decides when and which gas pressure inlet valve  122  and  124  should be opened and closed for pressurized water tank-A  126  and pressurized water tank-B  128 . 
     Pressurized water tank-A  126  and pressurized water tank-B  128  are not simultaneously pressurized, the pressure applied to them is alternated by gas pressure inlet valves  122  and  124  under control of microcomputer controller  120 . What&#39;s important to the timing is the water levels inside the tanks, there are minimum and maximum operating levels that must be respected. Water inside one tank needs to flow out into the other tank through a water turbine, and the water cannot flow if the receiving water tank is pressurized at the same time. 
     In  FIG. 1 , an outlet valve-A  130  is opened to pass pressured liquid water (L) to a water turbine-A  134 . Similarly, an outlet valve-B  132  is opened to pass pressured liquid water (L) to a water turbine-B  136 . The liquid water returns from water turbine-B  136  through an inlet valve-A  138  back to water tank-A  126 . Liquid water from water turbine-A  134  passes on through to inlet valve-B  140  to water tank-B  128 . 
     The minimum and maximum operating levels of water that circulate between water tank-A  126  and water tank-B  128  are set by float switches (L, H)  142  and  144  for water tank-A  126 , and by float switches (L, H)  146  and  148  for water tank-B  128 . These float switches are connected to microcomputer controller  120 , and the readings are used to determine when to open and close outlet valve-A  130 , outlet valve-B  132 , inlet valve-A  138 , and inlet valve-B  140 . The float switch connection could be done wirelessly, and a local loop could be included to automatically close, for example, water outlet valve-A  130  when minimum level float switch  142  senses low water. 
     Each water tank-A  126  and water tank-B  128  should be equipped with a water to add make up water, and to drain water completely, e.g., during maintenance. 
     In  FIG. 1 , water turbine-A  134  is mechanically connected by a rotating shaft to drive a DC electrical generator  150 . The DC electrical power produced could be stored in batteries, and it is converted to AC electrical power by an inverter  152 . Similarly, water turbine-B  136  is mechanically connected by a rotating shaft to drive another DC electrical generator  154 . The DC electrical power produced could be stored in the same batteries, and it can also be independently converted to AC electrical power by an inverter  156 . The voltage outputs of inverters  152  and  156  can be stepped-up or stepped-down by conventional transformers as needed, e.g., to 110-VAC, 220-VAC, and 440-VAC. 
     Microcomputer controller  120  is connected to sense the electrical loads placed on inverters  152  and  156 , and uses the information to control how much pressurized water is needed to be passed through water turbine-A  134  and water turbine-B  136  to keep the overall operation in balance. 
     Once the pressurized gas inside the water tanks has done its job pushing out the water down to its minimum operating level, the residual pressurized gas can be vented out. For water tank-A  126 , a vent valve-A  160  is used, and for water tank-B  128 , a vent valve-A  162  is used. The residual gas pressures can be high enough to do useful work in a second stage generator. But any back pressure caused by the use of later stages can reduce the efficiency of the earlier stages by reducing the differential pressures between the pressurized tank and the vented one. 
     In operation, falling water levels inside the water tanks can be used by the minimum-level float switches  142  and  146  to trigger closed the associated water outlet valves  130  and  132 . This, in turn can be used to trigger closed the gas pressure inlet valves  122  and  124 , and to trigger open the gas pressure vent valves  160  and  162 . Similarly, the maximum-level float switches  144  and  148  can be used to trigger closed the water inlet valves  138  and  140 . 
     Pressurized water tank-A  126  and pressurized water tank-B  128  would normally be equipped with various conventional items not shown in  FIG. 1 . For example, inspection ports, drain valves, pressure gauges, pressure safety valves to release excess pressure, and a water make-up input to replace lost water. 
     Microcomputer controller  120  can increase and decrease the torque outputs of water turbine-A  134  and water turbine-B  136  by sending modulation controls to nozzle controls  170  and  172 . Alternatively, water outlet valve-A  130  and water outlet valve-B  132  could be continuously adjustable, instead of simple fully open, fully closed solenoid types. Such torque modulation would be necessary in some applications to balance the power being generated with the loads applied. In such case, inverters  152  and  156  would also be required to provide load measurements to microcomputer controller  120 . 
       FIG. 2  represents an electrical generator method embodiment of the present invention to cycle pressurized water between two tanks and two water turbines, as in  FIG. 1 . Such method is referred to herein by the general reference numeral  200 . Method  200  is implemented as a computer program in software or firmware executed by a conventional microcomputer, e.g., microcomputer controller  120  ( FIG. 1 ). Data inputs from sensors and switches are digitized for processing, user inputs are used to make process control decisions, and outputs to electro-mechanical solenoids are used to operate gas and hydraulic valves. 
     Method  200  includes three phases of operation: (1) startup, (2) power generation, and (3) shutdown. During startup, the operational pressures and valve settings must be initialized. During power generation, the gas pressure generated by the explosive cartridges must be switched between the two water tanks according to the respective water levels inside each. The amount of water forced between the water tanks and through the water turbines must be balanced with the electrical loads being placed on the system. During shutdown, the cycling must be stopped and the pressures relieved by opening the various vents. 
     Specifically, method  200  includes a step  202  for checking to see if the user wants to begin operation. If so, a step  204  closes the pressure tank and water tanks vents, and closes the inlet valves to the water tanks. A step  206  gets the gas pressure in the pressure tank up to operating levels by firing explosive cartridges as needed. A step  208  checks the water level inside water tank-A and if it&#39;s at its maximum operating level, a hydraulic cycle can begin. The gas inlet valve-A is opened, the gas vent valve-A is closed, and the water outlet valve-A to the associated turbine-A is opened. The gas pressure let in will push the water out through the outlet valve-A. When the water level reaches minimum, the outlet valve-A is closed. The gas inlet valve-A is closed, and the gas vent valve-A is opened. The water inlet valve-A is opened to receive water from water tank-B. 
     A step  210  checks the water level inside water tank-B and if it&#39;s at its maximum operating level, a hydraulic cycle can begin. The gas inlet valve-B is opened, the gas vent valve-B is closed, and the water outlet valve-B to the associated turbine-B is opened. The gas pressure let in will push the water out through the outlet valve-B. When the water level in water tank-B reaches minimum, the outlet valve-B is closed. The gas inlet valve-B is closed, and the gas vent valve-B is opened. The water inlet valve-B is opened to receive water from water tank-A. 
     If the user is requesting a stop of operations, a step  212  passes control to a step  214 . Otherwise, the process repeats in a loop back to step  206 . Step  214  closes the gas inlet pressure valves to water tank-A and tank-B, opens the vents, and closes the water outlet valves to the turbines. Residual gas pressures inside the pressurized tank may be let down if another use cycle is not expected immediately. 
       FIG. 3  illustrates a single-stage system  300  that eliminates some of the duplication of the major components appearing in  FIG. 1 . System  300  assumes that when the water level in a water tank is below minimum, e.g., as detected by a low-water float switch, the water outlet valve should be closed. Similarly, when the water level in a water tank is above maximum, e.g., as detected by a high-water float switch, the water inlet valve should be closed. The gas inlet valve to a water tank can only be open if the gas vent is closed. The gas inlet valve to the water tank must be closed if the gas vent is open. The mechanisms implemented to enforce such logic can be built with relay logic, software, IC logic gates, and mechanical interlocks. 
     System  300  is powered by explosive cartridges  302  that are loaded in a magazine  304  and automatically fired under computer control in a breach  306 . Explosive gases are routed through a check valve  308  to a pressurized-gas tank  310 . A single 4-gang solenoid valve  312  and  314  steers high pressure gas to and vents gases from pressurized water tanks  316  and  318 . When one tank is being pressured, the other is being vented. A high-water float control inlet valve  320  automatically admits water to pressurized water tank  316  when the liquid level is below the operating range maximum and the other tank  318  is receiving gas pressure from explosive-gas tank  310  through 4-gang solenoid valve  312 . Another high-water float control inlet valve  322  admits water to pressurized water tank  318  when its liquid level is below its operating range maximum and its gases are vented. Similarly, a low-water float control inlet valve  324  shuts off water from pressurized water tank  316  when the liquid level falls below the operating range minimum. Another low-water float control outlet valve  326  shuts off water from pressurized water tank  318  when its liquid level is below its operating range minimum. Pressure safety valves (PSV)  330 ,  331 , and  332  release overpressures to protect the respective tanks from rupturing. 
     A water turbine  340  converts the hydraulic flow through it to a mechanical torque applied to a rotating driveshaft  342 . A second water turbine  344  converts its hydraulic flow to additional mechanical torque that is also applied to rotating driveshaft  342 . A liquid circuit  346  returns to pressurized water tank  316  through high-water float switch and valve  320 . A DC electrical generator  348  converts the rotating mechanical torque to electrical power that is converted to AC by an inverter  350 . Gears and pulleys in front of the generator may be used to adjust the speed and power input. Fill and drain valves are connected to the various tanks as appropriate. The system control signals may be supported on a computer network or conventional process control loops and can involve wireless connections. 
     A controller  352  operates the magazine  304  and breach  306 , and valves  312  and  314  to coordinate their timing, such that gas pressure from the pressurized-gas tank  310  is alternately routed to each pressurized water tank  316  and  318  until the liquid inside is pushed out into the other. The inverter  350  provides load sensing signals to the controller  352 . A throttle control  354  applied to control motors on valves  324  and  326  can be used to control the power output of turbines  340  and  344 . 
       FIG. 4  represents a two-stage electrical generator embodiment of the present invention, and is referred to herein by the general reference numeral  400 . Generator  400  uses explosive gases to pressurize water, and then uses two stages of pressurized hydraulics to spin electrical generators with hydraulic motors and turbines. A first Stage- 1  uses explosive cartridges to produce hot gases that will pressurize a tank  402 . Computer timing and valve control  404  steers the high pressure gas alternately to a first hydraulic pressure tank-A  406  and then to a second hydraulic pressure tank-B  408  according to their respective liquid levels. Water passing from the pressurized one of the tanks to the non-pressurized one is used to spin a hydraulic pump or water turbine  410 . Vent gases recovered from hydraulic pressure tank-A  406  and tank-B  408  are captured by a second stage gas pressure tank  412 . 
     The pressure loss in the gas pressures between the first Stage- 1  and second Stage- 2  is a function of the differential volumes of hydraulic pressure tank-A  406  and tank-B  408  as they cycle between their minimum and maximum water levels. 
     The second stage gas pressure tank  412  supplies gas to a computer timing and valve control  414  steers the high pressure gas alternately to a third hydraulic pressure tank-C  416  and then to a fourth hydraulic pressure tank-D  418  according to their respective liquid levels. Water passing from the pressurized one of these tanks to the non-pressurized one is used to spin a hydraulic pump or water turbine  420 . 
     Both water turbines  410  and  420  can be geared to drive a single DC electric generator  422 . The electrical power produced is temporarily stored in batteries  424 , and that can smooth out any voltage variations that would other wise result as the turbines are cycled between the hydraulic pressure tanks. An inverter  426  converts the DC power to AC power, and a transformer  428  is used to produce various commercial voltages, e.g., 110 VAC, 220-VAC, and 440-VAC at 50/60 Hertz. 
     Although the present invention has been described in terms of the presently preferred embodiments, it is to be understood that the disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above disclosure. Accordingly, it is intended that the appended claims be interpreted as covering all alterations and modifications as fall within the “true” spirit and scope of the invention.