20 junio 2010
Madrid Laboratory
Our new laboratory in Madrid is kitted out with state of the art lab equipment and our own design flat sheet test rig for membrane autopsy, cleaning tests and membrane characterisation. The lab now carries out between ten and twenty autopsies on reverse osmosis membranes every month, in addition to forensic type tests on nanofiltration and ultrafiltration membranes, cartridge filters and other parts of the pre-treatment system.
A membrane autopsy consists of detailed recording and external examination before the membrane's outer fibreglass casing is cut open and removed and the membrane leaves unfolded. The team take photos and record details of the membrane and feed spacer condition and take samples of deposits for further detailed analysis.
A4 size samples of membrane are then cut and tested for mechanical integrity. A vacuum test checks for leaks, a methylene blue test checks for oxidation and physical membrane damage, and a Fujiwara test checks for the presence of halogen as well as oxidation damage.
The membrane sample flow rate and salt rejection are characterised in the flat sheet test rig and compared with the membrane manufacturer's original specifications.
Samples of deposits are chemically identified using gravimetric analysis, scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDXA), x-ray diffraction analysis and x-ray photoelectron spectroscopy analysis (XPS). Microphotographs and deposit spectrum graphs are prepared for inclusion in the report.
Using attenuated total reflectance infrared spectroscopy (ATR/FTIR) the team compare the spectrum of the deposits found on the membrane with those of known chemical compounds. This enables them to identify the membrane foulant and suggest likely reasons for its deposition along with recommendations for minimising fouling in the future. Membrane samples are then tested in the flat sheet test rig with various cleaning compounds so the best method of cleaning can be established.
A membrane autopsy consists of detailed recording and external examination before the membrane's outer fibreglass casing is cut open and removed and the membrane leaves unfolded. The team take photos and record details of the membrane and feed spacer condition and take samples of deposits for further detailed analysis.
A4 size samples of membrane are then cut and tested for mechanical integrity. A vacuum test checks for leaks, a methylene blue test checks for oxidation and physical membrane damage, and a Fujiwara test checks for the presence of halogen as well as oxidation damage.
The membrane sample flow rate and salt rejection are characterised in the flat sheet test rig and compared with the membrane manufacturer's original specifications.
Samples of deposits are chemically identified using gravimetric analysis, scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDXA), x-ray diffraction analysis and x-ray photoelectron spectroscopy analysis (XPS). Microphotographs and deposit spectrum graphs are prepared for inclusion in the report.
Using attenuated total reflectance infrared spectroscopy (ATR/FTIR) the team compare the spectrum of the deposits found on the membrane with those of known chemical compounds. This enables them to identify the membrane foulant and suggest likely reasons for its deposition along with recommendations for minimising fouling in the future. Membrane samples are then tested in the flat sheet test rig with various cleaning compounds so the best method of cleaning can be established.
