BASF podcast outlines CO2 capture and separation

An August 2009 podcast from BASF provides the background to its activities in CO2 separation, gas scrubbing and potential carbon capture and storage (CCS) systems for power plants.

BASF provides the CO2 separation systems used in natural gas extraction, which is necessary before liquefaction, to enable the transport of liquefied natural gas (LNG).

In these systems, the gas is at a high pressure, typically 70 bar, and the solvents used to extract the CO2 are different to those that would be used for treating lower-pressure flue gases from a power station.

The CO2 stripped out is generally released back into the atmosphere or is occasionally used for enhanced oil recovery systems.

BASF is partnering with Linde Gas and LVE, a German power company, to install CO2 capture systems as a pilot plant on an LVE power station.

These tests will take another two years to prove the capabilities of the system.

Using mobile phone technology

The technology now available behind the mobile phone has introduced many new industrial applications using wireless communication, and radar for sensors, at reasonable prices. This year has seen an explosion of battery powered wireless sensor systems, largely eliminating the headaches, time and costs previously needed to install the new plant wiring for an extra monitoring point. A story last week from National Instruments announces their entry into the wireless field, with the NI Wireless Sensor Network platform for data acquisition systems feeding into LabView software. This is listed in the “Wireless Sensors” subject category on Processingtalk (Link), which now displays over 250 relevant stories, mainly added in the last year, making it the fastest growing subject section on the website. Interestingly NI say that their DAQ field mounted nodes are powered by four AA batteries for up to 3 years. Battery life, status monitoring and on-plant replacement seems to be the new headache introduced for instrument engineers by the clever wireless sensors, but we will probably soon see new developments in power sources following on, and will report them here.

Another review from Flowline describes their Flodar radar-based open channel flow measurement system, originally developed by Marsh-McBirney (Link). This article describes the principle of operation of the system, placing great emphasis on the way that regular sensor cleaning is not necessary, because all the sensors are above the sewage or effluent flow. Flow speed is sensed by a radar sensor monitoring the liquid surface movement, and liquid level is measured by ultrasonic pulse echo techniques, allowing the open channel flow computation by velocity-area calculations. Flowline claim the radar beam penetrates the surface sufficiently to make the speed measurement unaffected by wind effects, but I wonder why the system still uses ultrasonics for level measurement? Nevertheless Marsh McBirney claim to have supplied over 4000 of these systems, and Flowline show some interesting applications monitoring Anglian Water sewage works intakes, as well as trade effluent monitoring systems in Wilton.

Honeywell certainly believe in radar for level and tank contents measurement, and their latest story, on the wireless sensors topic, reports that their Flexline Wireless Radar Gauge, using both radar and wireless comms, is delivering level measurements to control room operators, in systems approved by the Dutch authorities for ship and truck unloading (Link). I also found the recent Emerson story of a control system upgrade of interest, where DeltaV workstations have replaced aging Bailey HMI systems on an Algerian oilfield, yet still interfacing to the legacy control system, a Bailey INFI 90 DCS (Link).

Using nano-fluid-magnetic effects

My new word for today is ‘Struvite’. Naturally this mineral was named after Heinrich Christian Gottfried von Struve, who discovered the phosphate crystals in medieval sewer systems in Hamburg in 1845. Struvite is ammonium magnesium phosphate, and is most commonly found in kidney stones: but it is also a problem in sewage and waste water treatment, particularly when formed in anaerobic digesters, after the release ammonium and phosphate from waste material, as it forms as a scale on pumps and lines and clogs system pipes!

So now we all know. There are a couple of ways of getting rid of kidney stones, but how do you clear Struvite from digester discharge pipes? Well Environmental Treatment Concepts have applied their Scalewatcher Enigma units for East Worthing Treatment Works as a solution to a Struvite build-up there, which has solved the problem! The Scalewatcher is a magnetic water treatment system, normally used to prevent lime-scale in water pipes, heating or cooling systems. The Carbon Trust states that 1mm of limescale can increase energy costs in heating systems by 7%, enough justification for adding large quantities of expensive water treatment chemicals: or for investigating alternative “external” treatments such as the Scalewatcher. Back in 2003 a Processingtalk article explained the Scalewatcher principle: basically the alternating magnetic field imposed on the water flow crerates new nucleation sites within the flowing liquid, for the precipitation of the scale within the flowing liquid, rather than on the walls. Looked at another way, it is micro-particle technology, if not nanotechnology, being applied to every day industrial problems. And the Southern Water application is likely to save them GBP100,000 this year (Link).
Scepticism is OK: it has its place. But let’s push on, one step further, and apply some similar alternating magnetic fields to the fuel lines supplying steam boilers. This is what Maxsys do, with their Fuel+ system, (Link). The finely calibrated magnetic treatment has to be operated within 1.5m of the burner, and the result is a 5% fuel saving: guaranteed. The numerous Maxsys case studies on Processingtalk show this 5% remarkably consistently, but occasionally give higher savings: typically the systems before and after are audited by ABB Engineering Services, who have independently confirmed the results. And these installations are at companies like Dow Chemical, Cray Valley, First Milk Cheese Company, Findus, Ford.

With me so far? OK. So you can envisage some effect of micro-particle clusters, nano-technology effects, nuclei in the fuel oil that make it separate and burn more efficiently, to produce these gains. But – most of the companies quoted above use natural gas as their main fuel, ie methane, which is really not normally well known for magnetic interactions, or nuclei. So belief is getting a little strained maybe? Maxsys commercialised this system in 2003, based on a strong working relationship with Aston University, which includes the CFD expertise of Dr Sotos Generalis. Dr Generalis and a colleague from Tokyo have just announced the discovery of a rigid structure which exists within the centre of air turbulence. They believe this new ‘Hairpin Vortex Solution’ could revolutionise the understanding of turbulence, and provide an ability to control it.

I think it is time to start looking at these magnetic micro, or nano-effects more closely: on a similar topic there are also other ideas from the NanoKTN and the TSB funding for the Energy Generation and Supply KTN reported in the Processingtalk newsletter this week.

Look up, and think about dust

Featured on the website last week, and in the technical articles in this week’s newsletter, is a new safety video from the US Chemical Safety Board. I can now hear you getting bored! But this one kept me watching the whole inevitable build-up to total plant destruction via chain-reaction explosions, in three separate major accidents, all fed by unseen dust accumulations: and all starting from far less significant incidents. The animation and explanation from the CSB is excellent: while the full video is 30 minutes, the time spent watching it could be invaluable.

These were not run-down old fashioned plants, these were modern plants, one a clean looking pharmaceutical components plant. Several of them had passed operational safety inspections ‘with flying colours’ in the weeks prior to the explosions, but not even these Government officials carrying out the safety inspections were tasked with thinking about combustible dust hazards. The causes are not some exotic effect like electrostatics, but normal, small plant incidents, which set off the whole reaction chain.

Legislative changes are at last coming, with the new US administration looking to add checks on combustible dust hazards to factory inspection and safety regulations. The CSB has been at the forefront of the pressure groups trying to get this implemented in the USA, after having seen over 281 fires and explosions of this type in 25 years, with many workers killed and injured: for example 14 workers were killed at a sugar plant explosion in Georgia. And that was in 2008, as recent as last year!

Read the story now, on (Link), then view the video on line, via the CSB website, (Link), or YouTube. Then I challenge you to walk round your plant without a quick glance upwards, to see the heaters, cable trays, pipe and duct work in your roof spaces!