Chemical injection packages for the oil & gas industry
Overview of chemical injection applications:
Over the years, with the depletion of many onshore fields and offshore drilling going from shallow to deep water, the use of chemical injection and so the use of the corresponding metering and injection packages has increased tremendously.
The flow rates and the injection pressures required have increased continuously. From formerly 0,05 - 0,5 l/h to several thousand litres per hour, from onshore pipeline injection at 50 - 70 bar to offshore umbilical applications with 900 bar and more.
Many chemicals have been and are being used. A switch from diluted chemicals with water or diesel base (often 9:1 - diesel/water/chemical) to lean injection took place over the last 15 years. This switch has added new challenges to increasing flows and pressures - higher viscosities and corrosive behaviour of e.g. lean corrosion inhibitor.
The main chemicals used for oil & gas and sea - fresh - waste and re-injection water are:
|
|
|
and mixtures of these fluids or new fluids such as methanol substitutes (LDHIs).
LEWA has a modular metering pump and process pump system supported by a full range of accessories, electric and/or electronic devices to the standard or specification required. Moreover LEWA also can provide pressure vessels to American, English, German or any other standard together with any pipe rating or design specified for a certain application (35 5500, ASME VIII, HP, AD, ASME "N").
Because of the many years of experience at all locations worldwide designing, manufacturing and testing to customer regulations is a daily standard. Fitting a chemical injection package into limited space, coping with high suction and discharge pressures, a harsh environment, abrasive slurries, low temperatures, 24 hour operation over many years - LEWA is a sound, proven, reliable and trustworthy partner of the oil & gas industry – all over the world.
- Please click on the images to enlarge
Examples of the excellent design capabilities of LEWA, showing pictures and providing a short description of some of the many packages supplied.
Small, movable chemical injection packages designed in two parts, easy to carry on a helicopter and clamped together to a functioning unit fast. Used for testing the moisture content in the gas on forwarding platforms to prevent damage to the compressors caused by an elevated water content.
Installing a chemical injection package on an existing platform with limited space is a special challenge even for experienced designers. As the field gets older the need for chemical injection comes up or changes as different water combinations are pumped back to retain the field pressure or water seeping into the cavities forming. The chemicals must be introduced and so new equipment from mixing to injection packages must be installed in an already well cramped area.
Space saving and trouble free operation:
A multi-compartment tank (in case of several chemicals) will save floor space and a separate mixing and injection package can be installed in different, available locations and hooked up by suitable pipelines and electrics. The pumps can be bracket mounted to the tank provided. The pump can handle the suction lift - no problem for LEWA diaphragm pumps. A set of duplex pumps discharging simultaneously can provide excellent and accurate mixing through an inline mixer saving power. Saving power is another objective as frequently very little power is freely available on a platform years after the installation. Therefore the highly efficient LEWA pumps offer further advantage!
The high quality of LEWA pumps assures years of trouble free operation and its user-friendly design allows fast repair in case of problems. So in some locations the customer even waived the need for stand-by pumps and only stored one common warehouse spare.
Condensate injection:
LEWA's experience and computerized calculation methods allow a precise evaluation of an existing location and the installation of an adequately designed condensate re-injection or forwarding package even at very low suction heads (in the example about 60 cm). By adding suitable booster pumps to feed the condensate to the process diaphragm pump suction and so safely preventing vaporization with all its negative, damaging side effects. Designing the supporting vents, cross-over connections and monitoring equipment for easy, safe and reliable operation is state-of-the-art for the design engineers involved. Using materials resistant to the corrosive and abrasive contents of the condensate also does not pose any problems.
Methanol injection:
High pressure injection of methanol, receiving the fluid at a high transfer pressure from another platform and then boosting it to 350 bar was only one of the challenges at this package's construction. The existing crane on the platform could only lift 7.5 tons, the total weight of the package was 15 tons. The main reason was the size of the pumps, but also the specification for 2" 2500 lbs RTJ connection making the pipelines extremely heavy. Having to design the local controls, wiring and motors in explosion proof design did not help the weight problem at all.
The package was split in the middle. Guide bolts and supports made re-assembly easy once on location. LEWA engineers met the weight estimated on the nose much to the relief of a satisfied customer.
Packages with flow meters and explosion proof controls:
Supplying a small foot print package with flow meters and explosion proof controls to the Far East was another special job LEWA had to tackle. The flow rates were extremely low, the space available, as usual, very limited: LEWA provided a sound technical solution which, in the meantime, is in operation for several years under demanding conditions.
World's biggest quadruplex pump by LEWA:
Since many years the demand for fertilizers has decreased so H2S is no longer treated or processed, but re-injected into the depleting fields. CO2, the main cause for earth warming, also came under special scrutiny of the local governments even levying penalty fees on CO2 discharge into the atmosphere. LEWA’s superior diaphragm technology and the fact that LEWA also supplies the biggest diaphragm pumps worldwide made it possible to install safe, hermetically tight pumping units up to a drive power of 1000 kW where other pump systems had catastrophic failures after a few hours of operation only. Safe for the operator and the environment and economical due to long up-times, easy monitoring and low spare parts requirements.
Special application examples - solar powerered injection packages:
Where no power is available or expensive to install and where sour gas driven pumps fail after days only - LEWA's solar powered chemical injection packages offer a proven (over 25 years) economical and low maintenance solution.
- Radio flow monitored, self-contained
- Flow rates to several litres per hour at 150 - 300 bars and more
- Buffer batteries for 24h, 7 days a week operation
Many units are installed in North Africa, the Middle East, South and Central America and other locations. LEWA can and will provide the solution to your specific problems.
Tailor-made odourant injection packages:
Natural gas does not smell. This makes possible leaks extremely dangerous.
LEWA offers a multiple selection of standard and tailor-made odourant injection packages, gas flow proportional, fully monitored and closed-loop controlled. The choice of any user for this demanding duty. LEWA diaphragm metering pumps with their fatigue proof stainless steel diaphragm offer years of continuous service, that means extremely low maintenance. To date over 5000 units were sold for central, de-centralized or re-odorizing as required.
Here LEWA will handle your challenging application. Your will get a solution providing safe, reliable and continuous operation right from start-up. LEWA also supplies blowing agent and additives' injection systems for extrusion processes, pumps, packages and systems for bio and gen technology, detergent plants, units for foodstuff and dairy applications as well as many other demanding, high technology applications.
We would be pleased to submit the corresponding information sheets on your request.
For chemical injection packages and systems with or without open and/or closed loop control, for regular or demanding duties to any standard specified - your expert partner will be LEWA no matter where your are located.
