Flow Research Evaluation Diagnostics - FRED Ltd








Indicative illustration items of past promotional pitches soliciting sales for sensibly scienced sounder solutions

Flow Research Evaluation Diagnostics - FRED Ltd

Associate Company

Tel:0121 471 4149 Fax:0121 471 4149

Email: Neale@Thomas.net Web: Neale.Thomas.net

Founded 1988 as a creative company for perspective projects principally on maritime military gizmos (acoustodynamic angles on material mixtures) but also furnishing flow-focused formulations to a considerable clientele of SMEs and MNCs. A decade ago FRED won four consecutive SMART Awards for a pair of environmentally friendlier industrial technologies (wind-driven sewage treatment, low-dose/drift agricultural spraying), both still patented but still only crawling toward commercialisation. NT's agenda now extends to mechanistic modelling of motivational determinants of innovation impact!




Hairy Roots for process biotechnology of plant products


PROFILE Natural products from cropped or collected plants abound as and are key to mainstream and fringe pharmaceuticals, also as flavourings and fragrances. Their market niche is protected by complexity of molecular conformation which renders synthesis unprofitable, combined with the confidence conveyed in “natural” which reduces regulatory resistance as well as instilling customer confidence. For a decade from the early 80s much expensive endeavour was given to evaluating innovative strategies for carrying these natural biosynthetic processes into the laboratory via plant cell suspension culture in bioreactors. In the absence of demonstrated prospective commercial viability, hardening hearts of the government funding agencies arrested these activities in the early 90s and only a handful of groups were able to persevere with laying the essential foundations. Fortunately in this select band because of corporate concern by a tobacco major on prospects for production of nicotine in smoking substitutes (sprays, patches, gums), my attention was redirected from cell suspensions to hairy roots as more promising avenue to stable synthesis, also for precursors affording product access by post-processing. Hairy roots are generated naturally by plants after opportunistic infection by the bacterium A. rhizogenes which is accompanied by gene insertion triggering growth of fibrous hairs. In the wild there is a natural synergy between the bacterium and host plant, notably for the plant as enhanced nutrient exchange via increased root mass which retains the plant genome and so can support reversion to the uninfected state. In the laboratory there is a major advantage of improved stability of hairy roots excised from infected plants as compared with cells in culture whose notorious unpredictability and mediocre productivity was the main cause of failure in this bioprocessing strategy as a practicable prospect. Plants vary considerably in their resistance to infection but many of most interest for alkaloid products are susceptible and often very substantially so in the presence of a suitably virulent strain of the bacterium. Screening of plant lines for susceptibility combined with productivity is a crucial element.


POSITION       Familiarisation with transformed Nicotiana species in benchtop studies in the early 90s was followed by demonstration of an innovative integrated bio-reactor / separator system conceived to cope with the special demands of root-mass culture and configured by analogy with tube-bundling principle employed in nuclear power technology. Thus rather than incur uncertain and expensive verification in scale-up, the strategy here is to validate at a suitably selected standard size with the desired total capacity achieved by multiple units operationally phased so as to provide essentially continuous production accommodating necessary biomass renewal by growth from inocula multiply ported into each tube at the required interval. Although in-house evaluation has extended to confident repeatable operation of an 8L unit, there remains a need to identify the optimal maximum volume recognising that internal wire-framing will be needed to support the root mass against weight compaction in very big tubes - compaction being undesirable not just for risk of tissue damage but for possible obstruction of gravity-drained liquid nutrient which is drip-fed from the top against an upflowing air stream for respiration. In production phase, the liquid stream is recirculated via an extraction column or, more precisely, this phase is alternated between product generation and elicitation using appropriate media compositions. The same approach has subsequently been adopted by other leading groups around the world which lends confidence in our claimed capability but equally represents a lost opportunity for commercial exploitation via appropriate IPR protection - the latter sought via academic avenues of my present affiliation but rejected for reasons unclear then and since (ignorance apart).


PURPOSE       Although patenting opportunities for the configuration have been lost, the system alone is by no means the key to commercial viability. Indeed, until very recently our best estimate based on a crude calculation indicated a shortfall factor two in price / cost ratio for the most promising products presently accessed. These comprise a family of tropane alkaloids from Datura stramonium of pharmaceutical value for their anticholinergic and antispasmodic activity - especially in the treatment of nerve gas poisoning. However, the impending closedown of our activity (the last one in this area in the UK) prompted a desperate final fling to close the gap and it worked! Specifically, by incorporating an additional ingredient into our soup of biophysicochemical co-factors the previously attainable performance has been boosted by a factor 16 and a further factor 2 appears accessible. This single element overwhelmingly outweighs all of the other “tricks” compounded over the past 5 years or so and truly represents a “Eureka” event in this arena. Factor 16 gain here means factor 8 as our revised notional price / cost ratio for these products and is comparable with expectations on domestic “gizmo” products so it deserves at least cursory consideration for commercialisation. Prospects for patenting are unclear and I am not prepared to release any indication of what is involved without a contractual commitment to proceed with exploitation on confirmation of the claimed capability. In other words, prospective partners must be persuaded that the market exists and that the margins are indeed as currently claimed (factor 2 short) and on this basis make the commitment to commercialisation subject only to confirmation that the further factor 16 is achievable as a demonstration. Crucially, our “Eureka event” is seemingly generic and the factor 16 improvement over previously reported best performance would suffice to bring many products within commercial viability locus.




Water Treatment as process integration in package plant


PROFILE  Bio-oxidation for quality restoration of wastewater requires energy for aeration and agitation. In nature the energy derives from wind transferred via waves which sustain gas transfer, especially at higher speeds with wave-breaking and bubble entrainment. Photosynthetic bioprocesses also contribute via algae but are not central to the compass of current consideration. Essential is recognition that oxygen deficits associated with natural detritus from decaying biology are (usually) substantially less than encountered with waste waters derived from human activities including not just as domestic sewage but also from intensive husbandry and industrial operations, the latter often with additional burdens of bio-resistive organic and metallic constituents. Of course, virtually all such substances occur naturally and so nature has assuredly evolved organisms that can metabolise virtually all, if not directly then at least adaptively and often co-operatively - for example, via cycling between aerobes, anaerobes and facultative microbes. However, the strength of modern effluent streams from intensified activities frequently defeats nature’s capacity for exploitation via digestion and assimilation as witnessed in eutrophication of soils by leachates from landfill sites, of inland waters by sewage discharges and even of coastal waters by run-off of agricultural fertilisers. A common fashionable deception is the belief that by extending “natural capacity” for digestion we can accommodate our excesses - viz engineered  reedbeds and wetlands. Truth is that process intensification is prerequisite for acceptable mediation of concentrated effluents because the limiting factor most often is oxygen transfer for maintenance of aerobic conditions in the treatment environment. Reeds are undeniably sustained by photosynthetic metabolism but wetland performance is effectively dictated by prevailing windiness rather than synergetic exchange via rhizomes. Arguably reeds provide no more than a passive substrate to support active microbial biofilms and in this respect they can actually suppress aerobic activity by inhibiting dissolution of oxygen in absorbing wind energy and thereby reducing agitation of the water surface. The health hazard posed by failed wetlands is now recognised especially Stateside where the technology was first introduced on substantial scales and we have brought to the EPA’s attention a simple scaling analysis by which performance expectation can be gauged largely in terms of site windiness, plus the prospect of mediation by retrofitted intensification zones powered by turbine-captured wind energy for augmented aeration by agitation. Process intensification and integration are the key ingredients to resolution of this emerging concern about the growing danger.


POSITION       Familiarisation with water treatment issues and remedies stems from my campus company’s receipt of technology innovation awards from the UK government’s DTI SMART scheme for SMEs, in particular awards received in the early 90s for concept evaluation of wind-driven treatment systems. Rules-of-thumb suffice to show that 6m/s ambient mean wind with 50% energy extraction efficiency furnishes enough power (40W/m2) to sustain agitation aeration (1kgO/kWh) to a depth of 1m for aerobic digestion (40mgO/Lh; x5 saturation per hour) of standard strength screened domestic sewage (400mgO/L deficit) in 10h providing the capture area matches the footprint area of the treatment tank. Standard strength here is roughly x400 the oxygen deficit of biological detritus in natural streams and intriguingly x400 is also roughly the ratio of wind power available above the ground to that absorbed as friction at the surface. These seductive scaling similarities equally indicate that x400 footprint area is required for wind-blown lagoons and wetlands (1m depth typically) of equivalent capacity to that secured from wind-powered plant for which compactness is comparable to that of conventionally powered plant. It explains why reedbeds are so expensive even compared with conventional tank treatment systems (80+p/m3 against 20p/m3), also why recent efforts have concerned their re-engineering to incorporate forced aeration by plunging or pumped aeration, the former conceived as being “natural” though of course sacrificed gravitational head is energetically equivalent. Captured wind power costing about £2k/kW pays back in 5 years on mains delivery charged at 5p/kWh (8kh/y) and 10 years is often adopted as effective working lifetime for package plant., indicating commercial viability break-point at £4k/kW for wind-turbine capital and maintenance (and repairs), this ignoring the cost for provision of mains or diesel power which may be substantial at remote rural locations. Note that the 10h treatment time adopted as basis here implies ~100L/pop (250L/d) so a guideline cost of tanking plus internals for agitation aeration roughly £200/m3 (power density above) provides baseline cost £20/pop or 2p/m3 over 10-year lifetime (100m3/y) or x10 margin commercial viability on market expectation price of 20p/m3. However, the basis of 6m/s ambient wind is certainly conservative for the UK where it ranges upwards from 6m/s to 12+m/s in Scotland and recalling that power goes as speed cubed, an ambient of 10m/s provides for x4+ increased delivery corresponding to x2 reduction in sizing of both turbine and tanking, likewise also treatment cost reduced to 1p/m3 or just 5% of the expectation price. Whichever way this cake is cut, the margins are massive enough to excite the most sceptical speculator if the basis is believable - and it is, really!.


PURPOSE       Although wind-powered plant was key to our conceptualisation in winning and executing the SMART project, hard-headed commercialism since dictated the turbine be shelved for plausibility with sector specialists in the UK. Crucially however, it was because of constraints imposed in configuring the process to accommodate vagaries in energy supply from wind that the resulting rugged integration of sequentially staged but intimately interfaced anaerobic and aerobic zones gave us an edge in bioprocess performance and resilience. In addition to novel blending of fixed and free biofilm supports within a single circular tank, we also won margin from a unique system for agitation aeration by snorkelling suction configured originally for versatile operability over the widely varying power supply. The principle here owes much to my experience of bubbly flow fundamentals, exploiting vorticity to induce suction for both induction and retention of bubbles within the working volume. Performance to date compares with industry expectations accompanied by economic advantages of simplicity in fabrication and operation, importantly also with scope for substantial enhancement in staying ahead of copycat competition. The unit is now trialling with a major UK utility company and has been laboratory demonstrated to precipitate metals in 24h from pH3 acidified waters. What it needs is business backing by professional punters with vision to endorse its exploitation in all of the avenues identified above.





Agrochemical Spraying halving both wind-drift and drop-size


PROFILE Multiple crop applications of insecticides and herbicides are long-established as a crucial component of agricultural intensification for economic production of food. The public may yearn for “natural” practices exploiting predator-prey relationships to reduce crop losses but the harsh reality is that seasonal uncertainties in the weather and hence population balances give rise to major excursions in efficacy which is inevitably reflected in variabilities of product quality and availability that the public won’t tolerate. Whilst genetic engineering offers the prospect of favourably shifting the productivity equilibrium there is considerable consumer resistance to these “unnatural” practices even compared with spraying which is certainly disliked but is tolerated by the public presumably because it is such a long-established and familiar procedure - akin to an uneasy alliance between silently hostile neighbours. Recognising this sensitivity, the agrochemical industry has moved toward reduced applications of supposedly safer products, recently even to the extent of evaluating such fancy schemes as GPS navigated patch spraying using automated pattern recognition to discriminate weed clusters! However, the underlying challenge remains improved utilisation of the introduced chemical and wind-drift is still the performance-limiting factor for timeliness in spraying whilst drop-size is still the performance-limiting factor for biological uptake per unit volume of application. Halving of both is way beyond the scope of existing spraying systems to the extent that such capability delivered at current expectations on cost will certainly pose substantial implications for sector resistance by the chemical companies as well as the spraying system suppliers. Anticipating such reaction precautionary protection has been pursued as patent applications lodged throughout Europe as well as the US and Japan, coverage for which the cost is ample evidence of our commitment and confidence in both efficacy and novelty of the physical principles in our innovation.


POSITION          Familiarisation with agrochemical spraying issues stems from my campus company’s receipt of technology innovation awards from the UK government’s DTI SMART scheme for SMEs, in particular awards received in the early 90s for concept evaluation of systems utilising externally introduced air as activating agent for dynamical control in droplet generation and translation. Long-established methods utilising pressurised hydraulic nozzles deployed on a towed boom still dominate the market but are under increasing threat from recent advances manifested in air-assisted approaches in which air is either injected internally to produce hollow drops on nozzle exit or externally to shroud the drops during transit to target. The former allegedly affords lower liquid use without the drift penalty incurred by hydraulic nozzles operating with reduced drop-size whilst the latter employs such nozzles on the understanding that drift should be inhibited by the co-flowing air. Of course, unassisted hydraulic nozzles also deliver droplets within a co-flowing  air-stream induced by momentum exchange and the volumetric flowrate of this entrained air far exceeds the volumetric flowrate of liquid - maybe upwards of x1000, approaching the flowrates of low-pressure “bulking” air employed in curtain sprayers (not a coincidence of course). On the other hand, air-injection nozzles employ much smaller quantities (x10 or so) but at high pressure as needed to generate a bubbly fluid composition on nozzle exit. Curtain sprayers thus sport clumsy fans and boom bags whereas “bubble sprayers” incorporate compact compressors but incur a practical penalty on power coupling and maintenance. The niche we sought to occupy neatly resides logarithmically midway between these extremes, quite literally with typical air flowrate ratio about x100 at pressures which can be met by a standard blower, much more compact than fan and bag assembly and more rugged than a compressor - not to mention cheaper on capital and maintenance as crucial considerations for the notoriously tight-fisted farming community. Essential distinctions are also reflected in the physical principles insofar as our concept is premised on the notion that it makes no sense to battle with air against high-pressure water inside the nozzle nor to battle with air against wind once the drops are on their way. The real window of opportunity exists in using air to forge the spray from issuing liquid outside the nozzle, more especially by playing a high-speed sheet on the breaking edge of the liquid fan. The aim (and achievement) was to excite a resonant interplay of stretching and bending motions where the film is thinnest and therefore most susceptible both for drop-size reduction and for drop capture and retention in the intensely vortical airflow induced by cyclical separation at the flapping salient edge of the fan. The mechanism is distinctive for its audible tone as droplet laden vortices transit at kHz frequencies, sufficiently high as to have no adverse implications for the footprint of such cluster spraying in terms of crop-coverage. Independent trials by Silsoe Institute have confirmed the central claim.


PURPOSE       Air-activated enhancement of agrochemical spraying has been demonstrated feasible and favourable. The technology is commercially competitive, comprising simply a set of air-sheet nozzles plus attachment clips and a standard blower (<1 barg, 5kW) plus air deployment lines. Pricing in line with market expectations for such products is projected to provide customer payback in 1 year on chemical saving compared with hydraulic nozzles, as against 2-3 years for air-injection and air-curtain sprayers. However, the margin would be modest (as it is for existing products) and maybe a premium price policy would be plausible always recognising the reluctance of this sector to spend unless a subsidy is on offer. Depending on infrastructure envisaged available for the activity, maybe lease-hire is an option here. Finally, please note that there is a generic gizmo on offer here and it’s always been my feeling that there may be much more scope for megamoney from applications in combustion, in firefighting, also in flash cooling and scrubbing, the first and last especially topical for control on HC/NOX and VOC emissions.





Viper = Vapour Implosive Pulsation For Extreme Reactivity 


CONTEXT Power density PD is the dominant determinant for accessibility to extreme reactivity whether it is procured from mechanical, thermal, chemical, acoustic, laser or nuclear drivers. Typical PDs encountered in the process industry utilising shaft-stirred tanks range up to kW/L or so. Typical PDs from combustion manifested in prime movers like engines deliver maybe up to MW/L. More exotic controlled sources associated with power ultrasound and flash boiling apparently range up to GW/L but access to TW/L is normally viewed as being the province of uncontrolled explosions rather than sustained operations. Explosions apart, the trend to higher PD is broadly accompanied by smaller spatial and temporal scales such that the energy exchange (EE = PD x size x duration) is substantially smaller in power transducers (say to 100mm and 100ms) than in processing tanks (say to 10+m and 10+h). Intriguingly, bursting soap bubbles represent MW/L PD sources though with extremely modest EE being delivered via 100 micron droplets expelled at 10 m/s or so. Worth remarking perhaps that meltdown and / or explosion at Three Mile Island was probably averted only by the extremely high heat transfer rates achieved in ultramicroscale flash boiling associated with bubbles on micron / ms scales presumably at number densities akin to those in emulsions


CONNECTION There is military and civil interest in power ultrasound respectively for sonar and process intensification, also for boosting the performance of diffusion limited exchanges in heat and mass transfer at boundaries. Perhaps the major obstacle here relates to lifetime limitations for the active heads of such transducers subjected to bombardment by microjets from collapsing cavitation bubbles, akin to the erosion-corrosion pitting incurred on surfaces experiencing high-speed translation motions or flows in excess of 25 m/s or so. This drawback is a powerful driver for consideration of configurations offering remote induction of cavitation such as are employed in so-called single bubble sonochemical applications where the aim is to achieve "super-symmetry" in the excitation of forced oscillations by the target. Under these conditions it has been found that an environment can be induced exhibiting extremes ranging to 10kK and kbar or so, albeit prevailing for duratons of only picos or so as extremely rapid spikes within forcing periods of micros or so (?). I believe the jury is still out between candidate explanations offered in terms of spherically convergent shock waves and ionisation effects (?) as most persuasive explanation but the former is certainly appealing if only for its more straightforward simplicity to a continuum dynamicist. Beyond obvious opportunities for exploring extremely fast chemistry / combustion (?) I understand that there has been much interest at Los Alamos Laboratory regarding the potential here for fusion induction as alternative to induction by laser pulsing. Probably the main point here is that exceptionally extreme PDs are delivered in these circumstances but on such small spatio-temporal scales as to be of limited obvious potential as an alternative to multibubble ultrasound for the military and civil applications considered here.


CONJECTURE Water hammer is widely recognised as a common cause of considerable mechanical damage associated with the impact of shock waves on vulnerable surfaces. Calculation schemes are well established and have been widely employed for such relevances but almost exclusively in terms of plane wave formulations or at most as gradually-varied modulations. Recent manifestations of this interest have been concerned with acoustic propagation in bubbly fluids, most often as confined fields in shock-tubes but also with recent interest in free fields of bubble plumes for purposes of protection against shocks as a weapons counter-measure and for transmission of acoustic signals in low frequency underwater communications. The essential point here is that intensification opportunities for planar propagation only really arise in connection with boundary impingement whereas for spherical propagation (above) intensification occurs intrinsically through convergence - and can be magnified by many orders of magnitude compared with planar shocks. However, unlike planar propagation, spherical implosive symmetry necessarily implies "disconnection" from the forcing device and efficacy is then dictated also by field factors and the far-field boundaries. An obvious compromise retaining connectedness of plane shocks and freedom for focussing of spherical shocks is afforded by cylinridical configuration. Moreover, cylindrical geometry also affords an opportunity to exploit coherent vortex induction of extreme subpressures  by axial straining as well as practical prospects for continuous operation or rather resonantly cyclic semi-continuous operation without the introduction of mechanically vulnerable moving surfaces. This, then, is the principle on offer as a system cycling between two end-states - one being vortex amplification by acceleration of axial flow, the other being shock generation by collapse of the vapour filled vortex. Key will be connecting the two as a resonant device to minimise the driving energy and this is where the IPR resides and is still available apparently. A benchtop unit would suffice both for feasibility and as demonstrator for commercial consolidation. Further information on indication of intent to adopt for evaluation, basis to be agreed by negotiation.