Fuel Gas Conditioning and Fuel Gas Skid

Natural gas is commonly used a fuel for combustion, this is also known as fuel gas. Most of the time, some level of treatment is required to ensure that this gas is suitable for end user. This is also commonly known as fuel gas conditioning and often packaged in a fuel gas skid. In conditioning of the fuel gas, heating, pressure regulation and filtration are commonly employed.

In terms of heating, some gas turbine manufacturer will required a 50 deg F superheat of the natural gas. In this case an electric heater is use to raise the temperature of the gas at least 50 deg F above it inlet temperature.  In some cases it may be desired to have an outlet gas temperature of 130 deg F or higher to minimize the deposit of sulfur in the combustion turbine. In this case an electric fuel gas super heater is employed to further raise the gas temperature.

Most natural gas supplies in the USA are derived from pipeline. Common pipeline pressure may range from 800 to 1300 psig. Hence it is usually desired to lower the operating pressure of the natural gas. In this case a pressure reduction station is employed to reduce the operating pressure of the natural gas. During the pressure reduction, the natural gas will reduce in temperature due to the JT effect. An electric fuel gas pre heater is commonly employed in preheating the gas to prevent freezing of the regulator or control valve.

Lastly, it may be desirable to remove liquid and solid contamination from this gas stream. A separator is used when minimal cleanliness is required. On the other hand, a filter / coalescer is use to provide high efficiency filtration.

In terms of fuel gas conditioning, we can provide the electric heater, pressure regulation, filtration or the complete fuel gas skid as a completed solution.

Performance Heater Skid

In a combine cycle power Power Generation, a performance heater may be installed on the fuel gas line to increase thermal efficiency of the plant. Heat from exhaust of the gas turbine is used to heat up water or steam. Water or steam in return is use to heat up the fuel gas. A shell & tube exchanger along with other components is part of a performance heater skid

Heat Transfer System and Hot Oil Skid

Hot oil skid also know as heat transfer system that are design to heat up heat transfer fluid for various process application. For instance, the heat transfer fluid may then be circulated around a shell & exchanger for indirect heating or heating of a die pelletizer in the polyethylene and plastic industry. They are generally a turnkey unit that may include a centrifugal pump to circulate the oil around the customer’s system. An expansion tank may be installed at the high point of the system. The tank not only serves to facilitate the thermal expansion of the liquid, they are also use to vent the system. A purging system should be installed on the expansion that if the heat transfers fluid is subjected to oxidation at the operating temperature.

Some of the recommended components and features of a hot oil system may include electric circulation heater, 2 x 100% centrifugal pump, and 300# flanges to better seal against high temperature application.

It is crucial that a proper thermal stress analysis on high temperature system to prevent leaks and equipment damage.

Liquid and Diesel Fuel Treatment Skid

Diesel engines and gas turbines (dual fuel) are commonly used as drivers in generators of a power plant. Diesel or liquid fuels are treated to ensure that they meet the fuel quality of the engine maker. Fuel treatment may include heating with an electric circulation heater to reduce viscosity, water and particulate contamination may be removing by utilizing one of our filters.

An unloading or forwarding pump may be found on these skids to facilitate the liquid unloading or transfer to the storage tank.

Condensate Stabilizer

With the advent of fracking technology in the oil & gas production. Hydrocarbon condensate is part of the product or byproduct of the process. Many times the condensate has to be stabilized (vapor pressure reduction) so it can be pumped or transported.

One method to reduce the vapor pressure is to heat condensate to flash off the lighter components. The residual condensate is then cooled down resulting in a lower vapor pressure liquid.

One of the equipment we offer is a condensate stabilizer skid that uses an electric heater as the source of heat in a kettle style electric heater reboiler.  Once the liquid is heater, we flash it thru a packed column. The heavy liquid is then recovered at the bottom of the exchanger where it is routed to a cross flow heat exchanger. The heat exchanger uses the incoming feed to cool the heavy liquid and help recover some of the heat.

The vent of the column is the off-gas that is routed to an appropriate place that can process this gas. One point to consider is the operating pressure of the stabilizer. The lower it operate pressure the lower the vapor pressure, however this may not provide sufficient pressure to push the off gas to the next recipient.