Process Metering Pumps — the Heart of a Metering System Precise Metering of Additives — All a Question of the Right Dosage
In the chemical industry, in power plants or on oilfields corrosion, deposits and the growth of harmful microorganisms can all result in system failure. In addition to preventive measures to avoid corrosion problems also scaling must be prevented. Only the precise interaction of metering pumps, controllers and sensors can guarantee fault-free operation with maximum safety.
Process metering pumps are the heart of a metering system, ensuring reliable and precise metering. In the following, three different examples illustrate how minimal use of chemicals reduce costs and protect the environment.
Corrosion-free Operation on a Drilling Platform
Operating safety and efficiency are main priorities for oil extraction. This requires systems to always be fully state-of-the-art. The offshore oilfield al-Bunduq has been online since 1976. The crude oil it supplies contains little sulfuric acid and is therefore of a very good quality and high market value. Corrosion inhibitors do still have to be added to the oil to prevent the acid from eroding the pipelines, causing costly damage and failure.
When the time came to renovate the platform, the operator therefore needed a modern system to meter these corrosion inhibitors. This proved particularly challenging because space on a drilling platform is very limited, so the system had to be extremely compact. Prominent was awarded the order to provide complete systems for metering the corrosion inhibitors. End of October 2015, a compact skid with two robust hydraulic diaphragm metering pumps Orlita Mfs was installed on the drilling platform. A 1,000 litre tank, all instrumentation and accessories are also accommodated on the skid. The electric actuators on the pumps are controlled by means of the process control system. The system was finally taken into service beginning 2016, ensuring corrosion-free operation.
Additives for Ethylene Production
The second example illustrates the role played by metering systems in an ethylene plant. One of the world’s biggest ethylene plants is being built in Tobolsk, situated in western Siberia, Russia. Scheduled to go into operation in 2021, the plant will produce around 1.5 million tonnes of ethylene every year, as well as propylene and butadiene, all important basic materials in plastic manufacturing. 25 stationary and mobile systems are planned for metering a wide range of substances, for example corrosion and polymerisation inhibitors, oxygen binding agents and anti-biofilm agents. With an explosion risk and outside temperatures as low as –52 °C, the systems must function reliably even under extreme conditions.
Prominent conceived and built a total of 18 stationary and seven mobile metering stations as complete systems in skids, which will simply have to be connected up on site and will then be ready to use. The wide range of applications covered by the metering pumps meant that all the required metering stations could be ordered from a single source. For the end customer, this reduces the costs of operation, maintenance and repair.
Eight systems destined for outdoor use are inside special protective “arctic shelters”, which create the same operating conditions as sealed rooms. When it came to designing the metering stations for this specific application hydraulic diaphragm metering pumps of the Hydro/2, Hydro/3 and Orlita Mfs series depending on the required pressure and feed rate were used. These are operationally reliable and durable pumps which offer dependable service even at high pressures. Their modular design allows them to be accurately configured for the required task.