Wednesday, July 8, 2009

Identification of bacterial species.

Questions about the identification of certain bacterial species are rising time after time. Paper mills - and their customers - are interested to know if the product, paper or board, contains harmful bacteria like food-poisoning bacteria, or even hazardous ones. Could terrorists inoculate a paper machine with Bacillus anthracis? Could Listeria live in wet end processes? Bird-flu?

Another reason for the question is the safety of working environment. Are high densities of bacteria in the wet end air dangerous?

Fortunately all information of the environmental needs, growth factors and capability to survive dry end treatment (="pasteurization") show that there is no need to worry if those real pathogens could be encountered in paper industry products.

There are still some areas inside paper mill where the identifications are needed, like

* food-poisoning, sporeforming bacteria (most important: Bacillus cereus)
* bacteria causing raw material breakdown (amylolytic ones etc.)
* potential primary attachers, causing biofilm formation (several genus)
* bacteria which can cause health symptoms and diseases(Legionella pneumophila, certain coliform bacteria)

Identification of specified bacteria from wet end population isn't easy task. Mixed population, sample matrix, low number of target organisms, their distribution inside the machine all lead to very challenging task.

I will refer the traditional and novel methods for the detection of specified bacteria in next posts. Coming back...

Sunday, July 5, 2009

Connections of paper industry microbiology to other sectors of microbiology: what is actually needed?

To make any definitions of paper industry microbiology, it makes sense to compare it with elder sectors of microbiology. Despite the microbiological problems of the paper processes and the paper products have been obvious since the beginning of machine-scale production of paper and board on 19th century, their effects have get worser when the scale, speed and raw material repertoir have increased during last decades. The tradition of the microbiological control, as well as the history of biocide research, intended in the "healthcare" of paper and board machines is therefore much shorter than in related areas like in dairy or food microbiology.

Paper manufacturing processes could be seen as ecosystems where several, complicated microbiological processes are continuing day and night. Microbial communities perform their important role as the actors of chemical transformations which shall modify most living and very many non-living substances into forms which will support the growth of other living creatures. Many species of immigrant bacteria, coming into the processes with the raw water, mechanical fibres and several additives, will feel fine: favourable temperature, pH level and nutrient concentrations, as well as good aeration and a huge supply of contact surfaces to build up biofilms, are available for them. They really do not make any difference between their lives outside and inside of the paper mill walls.

Unfortunately (not for the microbes but for the paper production) there are some features of paper machines which are similar with fermentor and bioreactor processes of biotechnological industry. So many growth factors (some of them were mentioned above) will be kept on so controlled levels that the adaptation of certain microbiological population cannot be avoided. It shall also be kept in mind that the long running periods will increase the microbiological risks by allowing long growing periods of microbes inside the machines.

How to control these problems?

Measures to dose biocidic compounds into the processes cannot be avoided because the conditions of paper and board machines cannot be adjusted on biocidic levels: the rise of the overall temperature over +80 oC is impossible, like the rise of pH value over 12. Before significant technical improvements to prevent the microbial growth in the paper machine processes could be done (if ever), the biocidic treatments and their rapid control methods like ON LINE biofilm measurements and frequent (at least once per 8 hours) AT LINE microbiological control of the main contaminating routes, wet end processes and towers containing white waters, pulps and brokes are the most important tools to secure the runnability of the machines and the quality of the products.

With the price of only 2-3 jumbo rolls can reliable instruments for the AT LINE microbiological control of the wet end processes be bought today. Alternative methods, many of them representing molecular biology methods, are available, but those which can show not only the counts of certain species but also the overall metabolic activities of the waterborne microbes and their potential to produce biofilms should be preferred. A combination of PMEU incubations and ATP Assays, with the addition of PCR if needed, is the most recommended procedure to show the effects of biocides on the microbial activity. PMEU method can be applied to biofilm testing, too.

The most important thing is that not only the counts of microbes (how high they may ever been) but also their overall metabolic activity and certain actions like breakdown of starches by amylase enzymes or production of H2S and H2 in anaerobic conditions shall be controlled all the time when the machines are running. All the laws of microbial ecology are present both in the nature and inside the machines - and they can lead to severe problems if counteracting does not work.

Sunday, June 7, 2009

"Top Three" microbiological problems of paper machines

Certain types of microbiological problems in paper mills seem to be acute all the time. Looking back to last months, this may be "Top Three" among them:

* Microbiological spoilage of raw materials. This is an everlasting hazard for mineral and starch slurries, and the reasons are very easy to understand: both raw materials mentioned may contain high densities of bacteria (mainly aerobic sporeformers and actinobacteria), slurries containing starch are very nutritive growth media for different microbial species and the very challenging biocidic treatments of slurries (especially mineral ones), when inaccurate, can lead to the total spoilage of them.

* Growth of biofilm and production of slime. This problem seems to be connected to poor washing and boil-out programs which leave rests of biofilm inside the machine and give growth time for it because too long running periods. The chose of ineffective biocide and/or its insufficient dosing can also stimulate the activity of these trouble-makers.

* Microbial growth in the broke system. Especially big machines with large broke towers suffer of this problem. If the basic biocide program is insufficient and the retention times inside the towers are too long, aerobic population tend to increase the number of its cells to the level of 10 000 000 cfu/g or even higher. Consumption of oxygen by respirating bacteria leads to anaerobic conditions, redox potential will be dropped and the growth conditions for both fermentative and anaerobic bacteria turns to be excellent. Drop of pH, slime and spore formation, smells and odours - even the production of H2S and H2 - will be found in such situations.

There are some measures to prevent these hazards. Growth period of microbial population shall be kept as short as possible, the control of waterborne and bioflim bacteria shall be as rapid and frequent as possible and the bioside programs, intended in killing of raw material, process water and biofilm bacteria shall be evaluated more frequently.

A realistic and accurate way to control both process water and biofilm growth, as well as to evaluate biocide programs, is now available. The Finnish company SAMPLION Ltd is manufacturing and selling "Portable Microbiological Enrichment Unit", a "mini-fermentor" for 10 simultaneous tests in controlled conditions, to detect the failures of biocide programs in only hours (watesr) or days (biofilms). Some results of PMEU's paper industry applications will be published in next Spring - coming back to refer them later.

Some wrong ideas about the overdosing of biocides will also rise up frequently among publicity. Basically it is not a question of only the cubic meters of biocides consumed, however, The chose of most effective biocides for different areas of processes towards different problems, the dosing of these compounds, their type of action and some other factors play a major role when building an effective biocide program for paper machine. Overdosing of biocides is a problem only in cases, when the program does not work, and leads to the loss of money and the rise of biocide concentration in paper machine effluents.

Thursday, June 4, 2009

What will the next Spring bring to Finnish paper industry?

After a most busy period in May 2009, IM would like to write something (partly because his insomnia - a common symptom during light & bright Nordic summer nights) to the readers of his blog.

Several seminars for the rise of Nordic forest industry have arranged and will be arranged before Finland "will be closed" for summer holidays. - This is, by the way, a common feature of Finnish lifestyle, and easy to understand: you shall first work in dark and rain for months, the temperature drops well below 0 oC, and you should try to be active all through the winter. But when the summer comes, everybody will wake up again and "see a light at the end of a tunnel" (which was the title in the annual meeting of Finnish Paper Engineer's Association). And then, during the summer months, citizen tend to move to their summer cottages and villas to just rest and collect forces to tolerate the next winter..

Back to the topic:

There was a certain drop in the number of visitors, speakers and companies with exhibition desks in the annual Congress "BioChem" in Helsinki, 27.-29.5.2009. It was a pity to see that a lot of paper industry-associated companies did not arrive to show their products. The depression of global economy was very easy to sense. After all: there were still active participants left, eg. the novel company SAMPLION Ltd. which is now distributing PMEU system for all areas of microbiological control.

Positive attitudes were obvious also in the annual "Summer Summit" by AEL, the major education company for adult professionals, paper industry ones included.

What will happen next? A conference, discussing of future forecasts of forest industry, will be held in the middle of June in Jyväskylä, Finland. After that the annual PIRA congress will be held in Barcelona, Spain, in October.

If only the paper industry research will be activated again..It is, of course, a question of money, but, after all: to leave brilliant Finnish researchers without work is really a vast of excellence. It has be proven several times that the rebuilding of research groups after a depression is a much harder work than to start those activities from zero. It would therefore be better to keep such organisations in work over the bad periods.

IM is looking forward to the next Autumn! A most interesting thing to see what are the forecasts of Nordic P&P industry when the summer is over!

Wednesday, May 6, 2009

What's new?

Last weeks have been very active in IM's life.

Annual meeting of Finnish Paper Engineers's Union (Paperi-insinööriliitto) has given some new opinions about paper industry in our country. Optimistic views were mainly honest ones, and the title of the meeting indicated better views into the future: "There is light in the other end of the tunnel"!

Training of paper industry employees seems also to be continued. AEL (biggest professional training coalition in Finland) kept a course of paper industry sampling a couple of weeks ago in Lappeenranta, and AEL and its smaller "competitor", Finn-Fiber Oy (especially focused on paper industry issues) are planning new courses to be kept already in next summer and autumn. It is very interesting to join the planning groups of these companies and be with when finding current topics and speakers for seminars and lectures.

Main issue, of course, are the measures to spare money, and in this context, it means better drive of the machines. Better sampling and faster analyses of the processes are most important ways to prevent all kinds of process problems and product faults, and the role of PMEU (Portable Microbiological Enrichment Unit) seems to rise even more: a new coalition of companies called Samplion Oy has started the mearketing of this microbiological analyse tool, and it will be presented on Chembio Fair at the end of this month in Helsinki, Finland. We'll meet by the stand of Samplion Oy!

Negative issues should also be mentioned. One of them is the market situation of Russian short fiber: Carelian companies shall fulfill their task to collect certain amount of birch logs, no matter they cannot sell them to Finland because high taxes, set by Russian government. IM wishes good luck for the negotiations about this problem!

We are living interesting times - let's see what happens in the area of paper industry in next months!

Wednesday, April 22, 2009

Most important issues in paper industry microbiology?

Referring the responses of the readers of IM blog, it seems that the most important issues of this QC area are:

* Klebsiella pneumoniae (and other pathogens)
* Activated sludge
* Economical effects of mb control for the mill

For some reason, no such interest has been focused to

* biofilms
* product hygiene
* raw material storage
* HACCP in P&P industry
* novel mb methods

IM is very pleased for the active visits on his blog page but, after all, will also be very pleased to hear questions about the issues mentioned above.

Looking forward to hear your questions,

IM

Sunday, April 19, 2009

Annual Award "Forest Industry Trainer 2008" by AEL

Microbiology has regarded as a considerable area of paper industry support by Finnish training institute AEL a couple of days ago.

This award was definitely an issue of personal satisfaction for IM. The fact that the role of microbiological control of paper mills has been taken into consideration is the most important thing, however. Courses and lectures of P&P microbiology will focus the attention of personnel in this industry to the significant spares which are resulted by better maintenance of raw materials, run of the machines and quality of the products.

This award was given in the annual meeting of PI, Finnish Society of Paper Engineers. The forecasts of speakers in this meeting were optimistic ones and opinions seem to be pretty positive ones. Funding of several paper technology students also indicates these feelings. The final conclusion of this meeting can therefore be: P&P industry is not a "sunset branch" of global economy, no matter severe economical problems have arisen during last years. Paper and board is still needed worldwide, as well as new fiber-based bioproducts. Feelings after the meeting were therefore very good, indeed.