Weights & Sizes
Weights & Sizes
Electric Steam Generator Corporation
Non-fluctuating steam pressure, stable temperature and automatically balanced electrical input are features engineered into SPEEDYLECTRIC Steam Generators and electric boilers.
In areas where scale forming water is used for make up, scaling with electrode steam generator presents a relatively minor problem when compared to fuel fired and resistance element electric boilers where extremely high heating surface temperatures bake on solids thrown out as water flashes into steam.
In SPEEDYLECTRIC Electrode Steam Generators, the resistance of the water to the passage of electricity generates heat and steam. No part of the generator is ever hotter than the water or steam itself. Therefore, no baking of solids or residue occurs. Furthermore, when the electrode tips become uncovered, no current can pass, hence, no low water damage can occur.
With Speedylectric you gain All these advantages:
· NO EXHAUST · NO FLAME · NO SOOT · NO BLOWERS · NO STACKS
· NO FIRE HAZARD · NO BURNERS · NO LOW-WATER DANGER
· NO FUEL PUMPS · NO TUBES OR COILS TO SCALE
· NO ELEMENTS TO BURN OUT · LESS CRITICAL WATER REQUIREMENTS
Contact us for details on the many Speedylectric parts that are interchangeable with Ebcor electrode boiler parts.
REDISCOVERING A NEW SOURCE OF ELECTRIC HEAT
THE ELECTRODE TYPE ELECTRIC STEAM BOILER
Generating Steam Electrically
There are two methods of utilizing electric power to generate steam in an electric boiler or steam generator. One is to pass electric current through a metal resistance-heating element immersed in water. The metal element resists the passage of current and develops heat, which by contact is conducted to the water and finally generates steam.
The other method is to utilize the water itself as the resistance element carrying alternating current between solid metal electrodes. The resistance of the water to the passage of current produces internal heat that results in rapid steam generation. Here, we are principally concerned with the later as Electric Steam Generator Corp. manufactures electrode type electric boilers under the SPEEDYLECTRIC brand.
The electrode method of efficiently converting electrical energy into thermal energy has been used in the United States for more than fifty years and for more than seventy-five years in Europe and Canada. The earliest form of electrode steam generators consisted of a perforated bucket hung within a pressure vessel into which were suspended metal electrodes. A variable output pump controlled the level of the water surrounding the electrodes and consequently the flow of current and steam production.
Electrode type electric boilers are available from one to over four thousand boiler horsepower.
Voltages range from 208 to 15,000. Wattage ranges from 10 kilowatts to 50 megawatts. Steam pressures range as high as 1,200 pounds per square inch.
Here we concentrate on what are considered low voltage steam generators using 600 volts or less and operating pressures of 250 pounds per square inch or less, as again, this is the type of electrode boiler manufactured by Electric Steam Generator Corp. These steam generators are commonly referred to as “point of use” electric boilers or steam generators.
A Few Electrode Type Electric Steam Generator Fundamentals In Non-Technical Terms
Electricity always follows the path of least resistance from the point of high potential (voltage) to a point of lower potential. If the power supply is single phase, sixty cycle alternating current, the flow of current in one direction for only one one hundred twentieth (1/120th) of a second.
Then the low potential contact becomes the high potential and the current reverses direction for the next 1/120th of a second and so on alternating as long as the power is supplied and connected to the current carrying medium. If the power supply is three phase, the high potential alternated between each of the three contacts.
As applied to Electric Steam Generator Corp. SPEEDYLECTRIC electric boilers, the current carrying medium is the boiler water itself and the power supply contacts are the electrodes.
Since the electrodes are always placed nearer to each other than to any other part of the boiler, the path of least resistance is a strait line from electrode to electrode.
Distilled water is a perfect insulator and will not carry current.
The capacity of water to carry current increases with the concentration of salts in solution. Let us assume a constant voltage or potential of 240 volts between one-inch diameter electrode tips spaced three inches apart.
Let us also assume a fixed salt concentration in the water. Then, the current carrying capacity of the water per square inch of cross section area will be constant, disregarding temperature corrections.
As an example, call it four amps per square inch. If the electrodes are immersed in the water to a depth on one inch and they are one inch in diameter, the segment of current carrying water will be bounded on four planes, each one-inch wide and the cross sectional area will be one square inch.
Therefore, the flow of current between the electrodes will be four amps. Now, if the water level is raised three inches, so that four inches of the electrode tips are immersed, the segment of current carrying water will again be bounded by four planes, the upper and lower of which will be one inch wide and the vertical side planes will be four inches long. The cross sectional area will now be four square inches and the flow of current between the electrodes will be sixteen amps.
In an electrode type electric boiler, the steam output for any given voltage is proportional to the current flow between the electrodes.
Once the temperature of the water in an electrode type electric boiler is at boiling, the flow of current may be increased by:
Electric Steam Generator Corporation SPEEDYLECTRIC electrode type steam generators are designed to work with artificially increased boiler water conductivity, greatly reducing the cycling up effect as additional electrolytes are carried in with the makeup water.
- Installing larger electrode tips.
- Increasing the current carrying capacity of the boiler water by adding mineral
salts (electrolytes) in solution.
- Raising the water level on the electrode tips, thus increasing the cross sectional
area of the current carrying segment of the boiler water.
In that the water in the boiler (with added electrolytes) increases in conductivity by roughly three fold as it warms up, say from 70 to 215 F. the cold-water conductivity should be observed by means of the ammeter when power is first applied to the electrodes. This is done to determine if the conductivity of the water needs adjusting by means of blowoff and replenishment (dilution) or the addition of electrolytes. The suggested cold-water startup amperage range is printed on the data plate, which is located on the front of the boiler cabinet.
Advantages of Electrode Type Electric Boilers
Conventional fuel fired boilers and electric boilers of the immersed resistive heating element type must utilize heat transfer surfaces at a temperature substantially higher than the desired steam temperature. The efficiency of such units depends on the efficiency of the conversion of fuel into heat and the efficiency of heat transfer. These efficiencies are highly dependent on heat transfer surfaces. Minerals are left behind and deposited on the hot heat transfer surfaces (scale) as the water flashes into steam. These deposits can greatly reduce heat transfer efficiency. With an electrode type electric boiler, heat is generated directly in the water itself, no part of the boiler is at a temperature higher than the steam being produced. The lower temperature reduces the tendency for scale formation and eliminates the problem of thermal shocking. Although scale, should it form on the electrode tips, increases maintenance requirements, it does not a loss in boiler efficiency or danger to personnel or equipment. Due to the electrical insulating quality of calcium scale, current flowing between the electrodes is slowed. In most cases, this scale can be quickly and easily removed from the electrode tips with a wire brush.
Especially when compared to conventional fuel fired boilers, electric steam generators of the electrode type are constructed with a vertical pressure vessel thereby resulting in a relatively small footprint, occupying less valuable floor space. Because of their small footprint, SPEEDYLECTRIC steam generators can be located close the load, reducing long, heat wasting runs of pipe.
There is no requirement for fuel handling space or equipment.
As an electric boiler has no stack, there is no related stack heat loss and there is no problem with air pollution due to incomplete combustion of fuel. The hazards associated with the combustion of fossil fuels are eliminated.
An electrode type electric boiler cools and restarts faster than other boiler types, reducing maintenance downtime.
The simplicity of the electrode type steam generator concept minimizes the number of controls, contactors and safety devices required.
Electrode steam generators are quick to react to sudden load changes, as there is no delay in transferring heat to the boiler water to produce additional steam.
With electric boilers of the electrode design there is no possible “cold water” shock danger.
Conventional fuel fired boilers and electric boilers of the immersed resistive heating element type are subject to failure with potentially disastrous results if the water level falls below some minimal point.
There is no unsafe water level in an Electric Steam Generator Corp. SPEEDYLECTRIC electrode type electric boiler because, if for any reason the water supply is interrupted, causing the water level in the pressure vessel to fall below normal levels, the electrode tips will become completely exposed. No current will pass between the electrodes, no steam will be produced and no hazardous temperatures can occur.
In an electrode type steam generator, 100% of the electrical energy is converted to heat. There are no stacks and no energy is used to handle fuel or air. Heat is lost in only two ways, through radiation and blowoff.
Electricity has always been considered a safe, clean, and efficient form of energy. In the past however, it was also expensive, particularly when compared with plentiful natural gas and cheap oil.
In recent years, with the rapidly rising cost of using natural gas and oil-fired boilers, electricity is increasing becoming a practical alternative source of energy. For the future, electricity enjoys one very important advantage over other forms of energy --- it can be generated from a number of power sources, including hydro, nuclear, fossil fuels, tidal, solar, geothermal and wind. A great deal of time, effort and money are being devoted to developing new technologies and sources of electric power.
Assembled in the U.S.A. for over 50 years.