Summary Description

This power plant uses time proven technology, and almost all operating  equipment is reconditioned used equipment. Operating pressure is 160 psi saturated steam. Steam is generated in two Keeler type boilers, fired by waste heat from municipal waste incinerator.
Turbine is General Electric three stage turbine with two velocity compounded stages and one low pressure stage. The turbine was built in 1916 and was relocated two times in it's lifetime. General Electric generator is capable to produce 1 Mw at 460 Volts 3 phase.
Turbine exhausts the steam into surface condenser which is cooled by circulating water from cooling tower. Condensed water is deaerated and pumped back into boilers. Generated power is used on site, powering the whole incinerator operation at about 220 Kw/h  consumption rate. The power plant operates at stand alone regime and is capable of steady 60 Hz frequency and steady voltage. The voltage regulator is  two transistor electronic regulator built by Dynamic Energy Corp. Voltage is regulated within 2 volt accuracy. System can tolerate shock loads such as starting 75 hp compressor when voltage drops about 200 volts, nevertheless, the voltage recovers and stabilizes in two seconds.
Power plant is completely automatic requiring only periodic checkup by incinerator operator who spends about 1 minute every hour in powerhouse walk trough.
Thermal efficiency of this power plant is very poor and a power plant of this kind is suitable only in applications where waste heat is available.  For economic reasons, such power plant is totally unsuitable for generating power from fuels which have to be purchased due to it's low thermal efficiency.
 
 

Power Plant Construction Picture from early stage of construction. Turbine was just mounted on the concrete foundation before the powerhouse metal  building was erected around it.  One Keeler boiler is seen on the left. Olivine type, 20 ft diameter vertical secondary combustion chamber is behind boiler.

Boilers

Two boilers are used to recover heat from municipal waste incinerator. A 1,700 degrees F gas enters boilers from secondary combustion chamber. This gas is completely combusted, therefore, no carbon soot deposits are formed on boiler tubes. Nevertheless, the gas stream contains a lot of particulate matter. Some of these particulates impinge on the first rows of boiler tubes and build up sandstone like crust 1 1/2" thick in two weeks. The color of this sandstone buildup is like desert sand and this is further testimony of complete combustion in Olivine type incinerator chambers.  This sandstone buildup cannot be blown off by an ordinary soot blower.  100 psi compressed air aimed directly at buildup is required to break up the sandstone crust from the first three rows of boiler tubes. Beyond first three rows the particulate buildup is powdery and easy to remove. The whole cleaning operation must be done during boiler shutdown. There is no slag problem, and in the whole history of boiler operation we never had fly ash fused into slag.  The sandstone buildup is mechanical in nature caused by particle impingement. Luckily this buildup can be broken up by compressed air alone.
Saturated steam is generated at 160 psi and is piped into General Electric turbine via 6" steel pipe.
Boiler make up water is taken from the deaerator tank and boosted to boiler pressure by multistage pump. Feed water is not preheated beyond 220 degrees F of deaerator temperature, however, the system would gain in efficiency from further feed water preheat.
Boiler water level is regulated by mechanical McDonell-Miller boiler controller which then controls pneumatically boosted water bypass valve. Electronic Water Level Controllers are used as back up.
Boiler overpressure is regulated via steam bypass valve, bypassing steam directly into the condenser. It is a pneumaticaly boosted valve and it's function is triggered by an optomechanical pressure sensor. Boiler steam pressure is thus controlled within 1 psi accuracy and it is able to hold the pressure 5 psi below safety valve blow off pressure.
 

Keeler Type Boiler Installation in Olivine Combusted gas enters the boilers via light colored ductwork from the secondary combustion chamber of Olivine type incinerator. Both boilers rely on waste heat only. There are no backup burners used. Each boiler is equipped with two safety valves.

Turbo generator

Turbo generator used in this installation is old General Electric unit built in 1916. Turbo generator was completely reconditioned by Dynamic Energy Corp. All parts were checked and remachined when required.
Turbine has three stages,  two velocity compounded Curtis stages and one low pressure impulse type stage. Turbine is capable of 1,500 horse power and is direct coupled to 1 Mw electric alternator. Turbine has mechanical speed governor actuated by fly weights. The governor motion is amplified by hydraulic cylinder which then drives the main steam control valve in turbine's inlet in order to maintain 3600 revolutions per minute.
Electric output from the alternator is up to 1,200 kw at 460 volts 60 Hz. Alternator excitation is controlled by  a belt driven DC generator and the alternator voltage output is controlled by electronic voltage regulator. Voltage range can be set anywhere from 440 volts to 480 volts.
 

General Electric Steam Turbo generator Direct drive 1 Mw turbo generator set Exciter is belt driven dynamo (on the right). This unit was built in 1916, was relocated twice, and it was completely reconditioned for this job.

Control Panel

The control panel for the above generator was built in  1960 and again it was rebuilt by Dynamic Energy Corp. for this installation. The power plant has an independent control panels separate from incinerator control panels. There are two control panels. One is totally devoted to alternator monitoring and protection. The other panel is used to control entire power house equipment and switch gear.
 

Power Plant Control Panels We used most of the original equipment built in 1960. Some additional modern electronic protective relays were added to comply with utility grade requirements. Also, the original mechanical voltage regulator was removed and replaced with an electronic voltage regulator.

Switch gear

We used old Allis Chalmers 1,600 Amps breakers to connect or interrupt the electric power from alternator. These are  motor operated breakers for closing. Breaker tripping mechanism is actuated by DC electromagnet which is powered with DC current from large electrolytic capacitor. This ensures that there is always enough power to trip the breaker when all other power fails, as in the case of short circuit. Electronic protection relays are used to activate the breaker trip mechanism  when fault conditions get out of specified limit.  Two breakers are used. One breaker feeds electric panels for power distribution in the incinerator plant and the second breaker can connect electric power to utility grid.

Deaerator and Boiler Water Feed

Spray type deaerator is used. ( Deaerator is a device to remove dissolved oxygen from boiler feed water ) . Condensed water from the surface condenser is pumped via spray nozzles into a low pressure vessel where the water is contacted with steam. Steam heats the water to 220 - 250 degrees F. Over 99% of dissolved oxygen is driven off once the boiling point of water is reached. The residual oxygen is scavenged by Sodium Sulfite chemical. The removal of oxygen from boiler feed water is of the out most importance because the dissolved oxygen in feed water can damage the boiler by pitting, leading to boiler destruction.
Deaerated water is pressurized by electrically driven multistage pump and is ready to be injected into boiler on demand. The pressurized pump outlet piping has a bypass valve to return water back to pump inlet when boiler water level controller demands less water.  This system assures the constant flow of water trough the pump, an essential requirement for a proper performance of multistage centrifugal pump. The system has one standby back up pump which starts automatically when boiler water level drops below certain level.
Water bypass valve is pneumatically operated to on or off state. The signal to operate this pneumatic bypass valve is taken from McDonnell-Miller boiler controller There is also back up from two electronic water level controllers.
The overall system has high degree of reliability and the maintenance cost was less than $100.00 in years of operation.
 
 

Boiler Feed pumps and Turbine Exhaust On the left are two multistage boiler feed pumps. The pneumatically boosted steam bypass valve is located  in between large black pipe and  the huge 36" turbine exhaust pipe. This valve is holding steady 160 psi boiler pressure. Steam driven air ejector (vacuum pump) can be partially seen on the right.

Condenser and Cooling Tower

Condensing steam power plants have better thermal efficiency, hence if steam is not required for any process it is desirable to condense steam back into water and recycle the water back into boiler. Usually a surface condenser is used to condense the steam exhausted from turbine. Steam condensing must take place under deep vacuum condition. The reason for it is two fold. One, if the air is present in the condenser it prevents the steam contact with condenser tubes because the air is already occupying the space, hence the surface condenser will not operate properly if there is air in it.
Secondly, if the steam is expanded, via turbine, into deep vacuum more power is extracted from each pound of steam. It is desirable to hold the vacuum at minimum of 28.5 inches of mercury. If there is enough cooling water of low temperature it is easy to reach 29.5 inches vacuum. The theoretical 30 inches of vacuum is impossible to reach, therefore, 29.5 inches is very good vacuum. Steam driven two stage air ejector is constantly operated to keep ahead of infiltrating air leaking into the condenser system.
Surface condenser ejects a massive amount of low grade heat, therefore, a lot of cooling water is required. The steam temperature entering the condenser under 29 inches of vacuum is about 100 degrees F, however, the enthalpy ( heat content ) of steam is still over 1,000 BTU per pound, hence you can see that a huge amount of heat must be ejected into cooling water. For example: If the turbine uses 20,000 pounds of steam per 1Mw / per hour ( modern and large turbines use less steam, some below 10,000 lb per 1Mw/h ), it means that over 20 million BTU of heat energy must be ejected into cooling water.
The most common method of providing cooling water for condenser is to recirculate cooling water via cooling tower where the recirculating water is cooled by evaporation and air contact. In our installation we use a refrigeration type cooling tower. This cooling tower is of compact round design with rotary water distribution over the evaporative surface. Motor driven cooling fan of 10 feet diameter is used to provide air movement through the cooling tower. Water recirculation is at 1,400 gallons per minute. The power consumption for air fan and recirculation pump is only 15 Hp. This is very efficient, due to low height difference between condenser and cooling tower discharge, therefore, the pump doesn't have to lift water too high, resulting in power savings.
 
 

Cooling Tower Refrigeration type cooling tower. Water is pumped via underground 8" pipe and enters through the centre into midd section of cooling tower where water is sprayed  out of rotating sprinkler onto cooling tower packing. Water is passing counter current to rising air. Cooled water is then recirculated through condenser.

Chemical Water Treatment

Every steam power plant requires some chemical water treatment for uninterrupted reliable operation. In our installation, we provided an inexpensive yet very effective water treatment system. Water softener is the first most important device in water treatment. Savings in chemicals will far outweigh the cost of water softener.  The softened water is further treated with three chemicals. Sodium Sulfide is used for residual oxygen scavenging. Sodium Hydroxide is used for PH ( alkalinity ) adjustment, and Phosphate is used as an anticorrosion agent to protect piping in condensate system.
Cooling tower uses two chemicals. One is anti scaling agent to prevent lime scale build up in recirculating system. The other chemical is anti algae agent. Without this chemical there is a problem of algae slime build up on all parts of cooling tower.
Chemical dosage is monitored with chemical analysis because too much dosage would waste the chemicals and too little could result in some problem.

Conclusion

The above described power plant was designed and built by Dynamic Energy Corp.  The total cost of purchasing used equipment, reconditioning and direct labor in construction was about US$ 150,000.00 and it took more than one year to finish all equipment reconditioning and construction.
The operation was trouble free so far, maintenance is mainly consisting of labor cost for chemical monitoring and preventive maintenance. The operating cost is low and it consist of annual boiler inspection and fees, less than $1,000 in chemicals per year and boiler safety valve reinspection and retesting in certified shop.
Operation of power plant is completely automatic, therefore,  it doesn't require additional personnel to operate it.  The incinerator plant supervisor and  incinerator operators are running this power plant.

Company

Dynamic Energy was incorporated in Delaware in 1990, and this company is also registered in Washington State.  The company was formed specifically to build and operate the steam power plant at Olivine Corporation in Bellingham, WA
The company was involved in managing the construction operations and then managing the plant operations.
Now the company is in the process to expand it's operations into manufacturing of various metal and electronic products in the Philippines under the name Unity Machineworks Inc.
 
 

NOTE: The Dynamic Energy Corp.  is available for hire anywhere in the world  for consulting, designing, building or operating your steam power plant. Our expertise is in Municipal Solid Waste Incineration and wood waste incineration with the addition of power plant design and an  environmental anti pollution design.

People involved in Power Plant construction / operation

Listing starts from the beginning of power plant construction for all people who participated in administration, construction work and operation. Two companies were involved.

Office Administration ( Olivine Corporation) Corky Smith Sr.,  Corky Smith Jr., Mae Smith,
                                                                            Tom Dutcher, Katleen Perkins, Rolf Nilsen

Job Design and Supervision (Dynamic Energy Corp.)  - Frank Kandrnal

Foreman - Jim Prince  &   Riley Cunningham

Construction Labor  - Tim Tracy, Doug Corning, Jerry Hansen, Antonin Gajdosik Sr.,
                                      Abe,  Paul Wright,  Antonin Gajdosik Jr., Vic Hubacek, Peter Carlich

Purchasing - Pamela Clayton,  Tanya Kandrnal

Incinerator/Power Plant Operators - Tom Creel,  Bradley Mumm, Larry Thompson,
                                                             Modesto (Nino) Silva, Robert Davies, Don Burton,
                                                             Bob Johnson, Luis Gierke, Randy Flather

Plant Operations Management ( from 1992 to 1995) - Frank Kandrnal

Plant Operations Management ( from 1996 )  -  Jim Prince

Machine Maintenance - Dave Devaney

Water Treatment Monitoring -  Tanya Kandrnal, Marwin Woods