Before being used, crude oil and natural gas are being processed in refineries into mineral oil products such as petrol, diesel heating oil, etc. or pretreated as chemical raw materials. Most of the oil and gas extracted goes to the heating and energy market, only one third is being used in form of chemical raw materials. Petroleum and natural gas products are processed into numerous household and industrial products, e.g. cosmetics, household cleaners, vehicle components and much more.
Online Process Monitoring with NIR Spectroscopy for a Precise Measurement of the Water Content in Oil
Process Analytical Technology (PAT)
Connection to control station
The exploitation of oil deposits is technically very complex and production costs are high. The major challenges of the petro chemistry therefore include, besides the development of new oil deposits, the increase of yield from oil fields that have already been exploited. For the optimal control of the production process and the best possible yield of high-quality oil, continuous monitoring of the water and gas content is indispensable. Excessive production can lead to dilution and a decrease in yield. To avoid this, it is important to collect and evaluate drill samples at regular intervals. Checking the water content during the production helps to optimize the pump performance so that in the end more oil can be produced in the same time.
The precise measurement of the water content in oil is not an easy task. Fluctuations of the solids, the gas volume fraction or variations in salinity can entail inaccurate measurement results. Besides, oil is very viscous and the environmental conditions vary strongly. Conventional measurement methods based on phase separation are often not precise enough and the analysis of the measurement data in the laboratory cumbersome and time-consuming. Due to the risk of explosion at the oil pipeline, products used in this environment must be certified according to the ATEX product directive 2014/34 / EUATEX.
A more precise measurement of the water content in oil directly at the pipeline and in real time can be achieved applying spectroscopic measurement methods. This measurement technique makes use of big difference in the absorption of near infrared light (NIR) between crude oil and water. The absorption spectrum is based on water, not on the dissolved salts. With the help of WLR (water in liquid ratio) sensors based on a NIR transmission measurement cell, oil, water and gas flow rates can be measured in real time and large-scale systems based on phase separation can be avoided. The risk of impaired measurement results due to emulsions or variation in salinity are eliminated.
Precise Measurements even in Harsh Environments - Hellma Transmission Probes Make It Possible!
For transmission measurements under harsh and strongly fluctuating process environments, Hellma has developed a product that is highly pressure and temperature resistant and, due to the material used for construction and the absence of elastomer sealings, completely maintenance free. The standard version, the Excalibur HD FPT, has metal sealing rings, the product variation used in the above mentioned application is realised with measuring fingers with soldered optics. Since the product is availabel with an ATEX certification it can be used in potentially explosive environments. Due to the sapphire measuring head this product is also pressure- and oil resistant.