Power Generation

Determine Fuel Quality, Ensure Optimal Combustion and Control Emissions

The wide variety of gas sources today has created new challenges for power generation (refineries, hydrocarbon processing plants, gas-to-power machines, biogas processes and fuel gas transportation and metering). Gas quality can vary widely, which can cause uneven energy levels and damage to turbines and downstream equipment. Power generators need to accurately establish gas energy and to determine fuel quality to ensure optimal combustion and to control emissions. But today's gas sources include conventional drilled gas as well as gas from fracking, biogas, etc. Each source may have different composition and may contain different levels of impurities.

Natural Gas Composition Analysis

Composition analysis of C1 – C5 alkane (methane, ethane, propane, butanes and pentanes) gases is important in various applications within the LNG industries, with applications ranging from quality monitoring during production, custody transfer, to its use in power generation. Advanced process control technologies providing fast and accurate feed and product analysis are critical in optimizing efficiency and payback in various processing stages. In power generation applications, on-line and fast sensors are required to ensure optimum combustion efficiency and acceptable emission levels. In LNG transport applications, fast and easy-to-use analyzers are desired to ensure quality at transfer points.

Optical Fingerprints of C1 - C4 Alkanes
Figure 1. Optical Fingerprints of C1 - C4 Alkanes.

The LNG industry has generally focused on large baseload plants on land for many years. However, in recent years, smaller plants have received considerable investments including Floating Liquefied Natural Gas (FLNG) plants. In these plants, simple, low-cost and maintenance-free online analysis is key due to CAPEX/OPEX tradeoff shifts. In addition, some of these plants are built in areas where access is limited, making complex analyzer system support cost prohibitive.

Natural Gas Composition Analysis Solutions

An all-optical hydrocarbon gas analyzer utilizing a Tunable Filter Spectroscopy “engine” has been developed and used in various natural gas processing applications from drilling to pipeline gas analysis in power generation.

The Precisive® 5 Hydrocarbon Analyzer from MKS is a stand-alone TFS analyzer packaged in a NEMA4X, IP66 rated, Div2/Zone2 certified box and is an attractive alternative to the traditional gas chromatograph technique in various LNG measurements. It provides speciated concentration values of methane, ethane, propane, iso-butane and n-butane as well as pentanes. From these values, calorific value and Wobbe index are computed and reported. Optional carbon-dioxide and hydrogen sulfide direct measurement channels are also available.

Syngas Reaction Analysis

The rising cost of fossil fuels and the worldwide need for reduction in green house gases have sparked renewed interest in alternative fuel sources that require less energy to produce. Gasification of biomass, coke and other residuals from petroleum, coal, municipal and industrial wastes can produce synthetic gas or "syngas". Syngas can be used directly as fuel; as well, it can be used to produce hydrocarbon fuels, hydrogen for fuel cells, and chemical feedstocks such as methanol. The analytical methods employed for quality assurance in syngas production must provide simultaneous and accurate data on mixtures of contaminants in the presence of high CO and CO2 content. The contaminant levels in syngas range in concentration from high ppm to % levels, depending upon the final product required.

Syngas product spectrum
Figure 2. Syngas product spectrum CH4 (Yellow), CO (Blue), CO2(Green), Ethane (Pink), Ethylene (Red), Propane (Dark Blue), Moisture (Purple) in a balance H2.

Syngas Reaction Analysis Solutions

The MKS MultiGas™ 2030 FTIR Continuous Gas Analyzer provides an effective solution for the simultaneous and accurate analysis of multicomponent mixtures such as those found in the syngas process. The high resolution (0.5 cm-1) of the spectra obtained using the MultiGas™ 2030 permits excellent speciation of like molecules, with the instrument capable of separate analyses for such similar species as butane, propane, ethane and methane. It also allows for low level analysis even in the presence of high levels of moisture (in particular, for SO2 and NOx).

Characterization of Photovoltaics

The sun provides 1 kW / m2 of free, non-polluting power for several hours every day. Thermal and photovoltaic systems take advantage of this as does the biomass. Coal, oil, plant ethanol, and wood are all forms of stored solar energy. While each energy conversion process has a unique spectral responsivity curve, most laboratory development work has concentrated on photovoltaic (PV) systems. Detailed knowledge of solar irradiance through the VIS and near IR is needed for cell optimization and economic viability assessment.

Characterization of photovoltaics involves measurement of current voltage relationships under standard illumination and temperature conditions. Surface reflectance, deep level traps, carrier diffusion, crystalline structure and boundaries, junction type depth and temperature, optical absorption and scattering, series and shunt resistance and photon degradation all influence efficiency. The spectral responsivity curve takes many of these fundamental effects into account, but should record the temperature and intensity level and other measurement conditions for completeness. For example, voltage sweep rates and direction and contact resistivity also affect I-V measurements. Simulator pulse duration is important for some heterojunction and electrochemical cells.

I-V measurement software suite
Figure 3. LabVIEW™ based I-V measurement software suite with an intuitive, easy to use interface.

Photovoltaic Characterization Solutions

Filtered xenon arc simulators are acknowledged to provide the closest match to standard solar light conditions. Oriel® Solar Simulators were used for some of the earliest development of photovoltaics for spacecraft, and we've improved them continuously.

The high color temperature of the xenon arc is particularly important for devices with blue responsivity. The small bright arc allows the collimation required for test purposes. Our beam homogenizers ensure output beam uniformity over the entire beam area, important for credible testing of any photovoltaic cell. Our power supplies alleviate concerns of output stability with arc wander is minimized.

Power Generation Products