In industry, it’s crucial to maintain uninterrupted production. In various sectors, efforts are made to create backup energy sources in case the primary source faces delivery issues. Consequently, for industries reliant on natural gas, an alternative gas source can ensure continuous production. Liquid petroleum gas (LPG) serves as an alternative to natural gas. Utilizing modern LPG Blenders allows for precise adjustment of gas and air proportions, depending on whether the system employs natural gas or LPG. This versatile solution guarantees a steady gas supply, even in the event of natural gas pressure drops or complete supply cutoffs.
Cost savings are highly valued in industry, but they cannot come at the expense of production quality or efficiency. Employing liquefied gas in industry significantly reduces costs. When high-quality components are used in gas installations, gas consumption can be further minimized. Properly selected LPG Blenders meeting top-notch standards result in reduced gas usage without compromising the overall system performance. This investment in a professional installation can quickly prove cost-effective.
How LPG Blenders Operate
The gaseous phase of LPG generated in the vaporizer cannot directly replace natural gas. LPG gas/air Blenders produce a gas blend with similar properties. This allows seamless switching between natural gas from the distribution network and the backup LPG system without the need to adjust burner settings, boilers, and the like. Basic Blenders use Venturi nozzles for mixing, while high-pressure installations employ patented Blenders with regulating pistons by AES.
History of LPG Blenders
LPG gas Blenders with regulating pistons gained approval through US and international patents in 1987 and 1992. Since then, AES has continued to produce them, incorporating some improvements in control components while retaining the fundamental design concept. AES installations worldwide encompass gas demand balancing systems, backup systems for industrial use, state and defense installations, primary fuel sources in areas without natural gas access or preparing for connection, as well as installations for power plants, glass factories, and brickworks.
Blenders with regulating pistons can be used with AES LPG vaporizers or with existing vaporizers from other manufacturers. Installation alongside vaporizers enables full integration into a versatile computerized control system for device operation. LPG Blenders find applications in backup installations, peak demand coverage, boosting natural gas calorific value with propane, and more.
Features of LPG Blenders
LPG Blenders with regulating pistons offer various advantages, including compact design, low maintenance and operating costs, high reliability, small dimensions, high efficiency, American and international patents, suitability for low and high-pressure setups, and applicability for backup and peak demand systems. They come in different capacities, optional integrated vaporization systems, automatic Wobbe index control, flow control systems, and remote control systems.
Additional Properties of Blenders:
- Flange outlet for LPG/air mixture
- Inlet fittings for LPG gas phase and compressed air, with both flanged or threaded options
- Electronic pressure relays for gas phase LPG, compressed air, and gas mixture
- Differential relay for pressure difference between gas phase LPG and air
- Suitable for indoor or outdoor use
- Produced in line with current technical knowledge
- Equipped with a pressure relief valve for safety, electromagnetic valve from the UL list
- Entire device holds FM approval
- Factory-mounted, painted, and tested
Optional Features of LPG Blender:
- Control panel upon request
- Integration system upon request for connection to the vaporizer
- Joint packaging with the vaporizer
- Platform and regular pads for installation with the vaporizer
- Flow meter with calculator
- Calorific value and specific gravity meters
- Automatic correction of gas mixture properties (calorific value, Wobbe number, specific gravity)
- Gas mixture temperature relay
- Supply gas phase LPG temperature relay
- Compressed air temperature relay
- Explosion-proof relays and control system
Applications of LPG Blenders
LPG Blenders with piston control obtained American and international patents in 1987 and 1992. Since then, AES has continued production with some enhancements to control components while preserving the core design concept. AES installations globally cover gas demand equalization systems, backup installations for industrial users, backup systems for state and defense facilities, primary fuel sources in regions lacking natural gas resources or preparing for natural gas connection, as well as installations in power plants, glass factories, and brickworks. Piston-controlled Blenders can be used with AES LPG vaporizers or existing vaporizers from other manufacturers, facilitating seamless integration with a versatile, computerized control system for device operation.
Operation of AES LPG/Air Blenders
Standard high-performance LPG and air gas phase Blenders for high pressures used to be complex, challenging to set up, and required frequent maintenance. In contrast, AES piston-controlled Blenders are straightforward and dependable, incorporating only two moving parts: a piston and a valve, ensuring durability and cost-effectiveness. Mixing is achieved by channeling LPG gas phase and compressed air through the Blender and blending them at the outlet. The Blender’s piston adjusts the air flow rate based on the pressure difference between the gas phase LPG and the air, which in turn controls the mixture’s proportions, including calorific value and Wobbe index. Electronic pressure relays ensure safe operation. The Blender’s compact design and high efficiency make it an attractive solution for various gas supply systems.
Automatic Adjustment of Gas Mixture Properties with LPG Blenders
All patented Blenders with a regulating piston (ranging from POM-30 to POM-80) can be equipped with this option. The regulator involves an electrical setting device attached to the POM valve and a dedicated PID controller. The PID controller receives a 4-20 mA signal from the GraviBlendTM-3 densimeter, comparing it to the desired mixture’s set value. Any deviations prompt the setting device to adjust the piston’s position in the POM valve, effectively correcting the mixture properties until they align with the customer’s requirements. When combined with the GraviBlend model with the “ACUCON” option, the PID controller’s operation integrates with the GraviBlendTM-3 microprocessor controller.
Specific Gravity Meter
The GraviBlendTM-3 densimeter measures the specific gravity of the LPG/air mixture. The output signal indicates the generated gas. Maintaining a constant specific gravity is crucial in situations where changes in gas enthalpy can affect burner or furnace performance and impact technological processes. When combined with the previous option, the densimeter’s signal can adjust the LPG/air ratio to rectify density deviations in the gas mixture.
Color LCD Touch Screen
The standard POM control panel includes an alphanumeric monitor with two lines and 20 characters per line. As an option, a color LCD display with a 6″, 8″, or 10″ screen is available. All LCD displays feature a touch interface for comprehensive control. They present various screens with soft keys and indicator lights, which change depending on system status and operator input. System data can be displayed in multiple languages.
Block-Mounted Installation (“On the Ram”)
In installations with limited space, the POM can be installed on a typical AES water vaporizer. This option includes placing the Blender control panel in the vaporizer control chamber and connecting all control elements and relays to the panel. This option is available for vaporizers from WB-1000 to WB-4500 and must be specified when ordering.
Dedicated Blender Building
In regions with extreme weather conditions, customers may require LPG/air mixing equipment to be installed in dedicated buildings. AES offers a concept based on modified 20 or 40-foot shipping containers, making transportation easy and avoiding the need for special permits. All equipment is pre-installed and tested, reducing installation time significantly. The typical building comprises a primary Blender room and a separate control panel room, providing an isolated space for operating personnel. Both building options can accommodate two Blenders, with the 40-foot building also including a compressed air room.
LPG/Air Blenders have been used for decades to produce Synthetic Natural Gas (SNG). SNG is a blend of LPG and air with the same Wobbe Index as Natural Gas (Methane). By matching the Wobbe Index, SNG has the same combustion characteristics as Natural Gas and can be interchanged with it freely. LPG/Air Blenders are used as primary fuel sources and standby systems. They are also employed in Peakshaving and CityGas applications.
Various types of LPG/Air mixing technologies are available in the market, with the most common being “Proportional” Blenders. These systems allow easy adjustment of the LPG and air blending ratio. The three primary technologies are:
- Piston Operated Blenders (AES POM)
- Floating Variable Orifice or Consta-Mix Blenders (FVO or CM)
- “Flow-Meter” type Blenders (sometimes called AFC)
While all these designs can produce acceptable SNG under ideal conditions, not all deliver reliable results under all operating conditions. The Piston Operated Blender (POM) by Alternate Energy Systems, Inc. (AES) is a well-established, time-tested design used worldwide for over 40 years. Its simplicity and reliability have led some to refer to it as “Old Fashioned.” At the core of the POM Blender is the patented POM valve, which employs a straightforward floating piston design to set the LPG and air blending ratio and match SNG production to customer demand. Unlike other designs, the POM does not rely on diaphragms, flow-meters, dynamic seals, or complex differential pressure arrangements, making it accessible to a wide range of users.
POM Blenders have seen continuous improvement in control components without significant changes to the main design concept. They have been approved by Factory Mutual (FM Global) and the Canadian Standards Association (CSA). Blenders with European CE Mark comply with all applicable EU Directives (ATEX, PED, etc.).