Sunday, November 15, 2009


I really loved to hear when politicians, ministers and even salesmen talked about exploiting energy or obtaining electrical from anaerobic digestion processes. It makes me wonder which end of their bodies are doing the thinking and talking. All of them have a very optimistic and simplistic view of exploiting the methane as the alternative energy source and to feed the electricity obtained into the national grid.
In any proposal it is very important that the economic and technical viability must first be established.
Let us look at the palm oil industries where there are talks about obtaining or trapping the methane generated. Mind you, the palm oil industries in Malaysia is not one or two years old. It is a very well established industry that has spanned several decades. Despite all these years they are still having problem of how to treat the palm oil mill effluent and exploit the methane gas generated.
I find it very hilarious despite having more than 400 palm oil mills, about 95% are still operating without methane trap.( (
What it implies here is that most of these palm oil mills are not having real modern anaerobic digestors to treat their wastes anaerobically but rely more on a series of stabilization ponds or anaerobic retention ponds.! Who can blame them? After all it is always cheaper and easier to let the wastes be collected in these ponds.
Now, the trouble with these anaerobic retention ponds are:
1 They are not operated or maintained efficiently
2 They are not equipped with methan trap such as methane hood to trap the methane
3 These retention ponds are not functioning optimally in terms of its various parameters such as ph, temperature, mixing, loading among others
4 I have my doubts if their desludging are carried out regularly….
A good anaerobic digestor producing methane efficiently would not give out that much offensive toxic smell generated by the hydrogen sulphides! Methane or even CO2 is odourless
Now we come to the second problem. It is not easy to generate electricity from methane gas. The methane gas has to be collected in substantial volume. It has to be scrubbed and removed of its water and sulphide content. It then need to be be compressed if they are going to use the gas directly. If they want to convert to electricity, the methane gas has to be used to drive the boiler and the steam generated used to turn the turbine to generate electricity! Electricity does not come from methane directly!
It requires so much investments and technical input, and if the process is not stable we have stucked anaerobic digestors!
This situation will even become worst for landfills. Please read my blog on the landfills…

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We can say that in the design of fermentors, the choice of impellers to execute the mixing regime has often been too over simplified. It is strange that despite the complex rheology of various fermentation broths, nost models of impellers are based on two main classes of mixings that is euther radial or axial.
Radial mixings are generated by impellers which are often based on simple flat blade design or variations of the Rushton turbine design. In radial flows all the mixing particles are brought out to the walls of the fermentor subject to tangentianal and centrifugal forces leading to formation of the common close loop pattern too commonly encountered in most standard text books in fermentation technology
On the other hand, the axial mixing are often brought about by the propeller design inpeller leading to the axial flow commonly visualised in ceiling fans
There are variations of mixings which integrate both the radial and axial flows io create a more effective hybrid flows
The important point here is that in the design of these main types of impellers, too much emphasis is given on the following:
1The fermentation broth subjected to mixing is Newtonian by nature
2 The properties of the fermentation broth do not change or remain constant
These kinds of conditions are not commonly found in the industrial fermentation industries. The fermentation broth is often more complex than expected to adhere to the Newtonian characteristics. Second, the volume of fermentation broth or fermentor is huge. This will make it very difficult for radial or even axial mixing to be efficient.
If we learn from blendings carried out in various chemical or even food industries, the type of mixers are often simpler. However in their cases their main requirements are just homogenization and that aseptic requirements are often not carried out during the mixing process itself
It is therefore very important that we need to come up with a very specific design for the mixing of specific fermentation broth and not have the “inbox mentality” of using the same standard impellers

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Saturday, November 14, 2009


The University Malaya Botanical Garden or Rimba Ilmu is treasure trove not often publicised to tourists and visitors. It is a unique Botanical garden which contain a diversity of plants from all over the country presented in an authentic forest atmosphere. A trip to the Rimba Ilmu is a wonderful experience into the types of plants which are of medicinal, economic and social importance to the nation

Who would have believed that just a few minutes from the Mid Valley Megamall and nestled within the campus of University Malaya in Kuala Lumpur, lies a secret garden. This secret garden or Rimba Ilmu has kept its secret for so long, and is only known to the very lucky few. It is a Botanical garden filled with a rich collection of plants and trees, some exotic and rare, and some you will commonly meet along the road journey in Malaysia.

So much effort, time, energy and expertise were invested over three decades in bringing and planting all these plants within the few hectares of land of the Rimba Ilmu. Now, many years later, the Rimba Ilmu has bloomed into a full and mature Botanical Garden which is one of the priceless assets of the University Malaya.
The secret and attraction of Rimba Ilmu is more than just maintaining a collection of tropical plants for research and teaching. The Rimba Ilmu is also a treasure and information trove about the rich culture of the people of this country and their dependence on all these plants from source of medicines, food, shelter and even economy.

Getting to the Rimba Ilmu or the University Malaya is easy. Take a taxi,or by Rapid KL buses or the Light Rail Transit train. If you are taking the LRT make sure you stop at the University Station and then find a taxi for the short distance into University Malaya

Entrance fees for the Rimba Ilmu is very cheap and its open working days.

It was the vision and the drive of the late Professor W R Stanton, who was then the Professor and Head of the Department of Botany, in the early seventies to see the wisdom of having a respectable Botanical Garden for future generations.

It was his driving force and persistence to see that the patch of old rubber plantation and secondary forest be successfully transformed into the Rimba Ilmu we have today
It is such a sad tragedy despite his priceless contributions to the University of Malaya, he is not even bestowed the honorific title of Emeritus Professor

During the early Seventies when University Malaya was the premier University it has large tracts of lands in the campus which remained unexploited. No one considered the importance of having a Botanical Garden until the idea of having a Botanical Garden was mooted by Professor Stanton.

At the Symposium held during the ceremonial opening of the Rimba Ilmu in August 1974, he said in his closing address:
"I suggest the golden age of botany is now and not in the 18th century, or some earlier era...we are beginning to find the raison d'etre for the great diversity of plant forms from the lowly algae and liverworts to the most stately trees of our tropical rainforest. The primary object of our new garden has been to provide the stage on which we may continue to act out the drama of Malaya's plant life for the benefit of the community. . ."

Professor Stanton is the millenium man with the foresight and vision to see the role and importance the Rimba Ilmu will play
The proposed design of the Rimba Ilmu was innovative. It would not look similar as any other Botanical Gardens. It is to be designed in such a way to reflect a rain forest garden rather than just any flower garden. It would not take the appearance of plants behind fences or in the pots, but as plants that occur authentically in nature.

Any visitor visiting the Rimba Ilmu will automatically feel the natural forest habitat as he appreciates the various plants and trees. This objectives will be faced with many challenges as the site of the proposed Rimba Ilmu was a secondary forest with rubber trees. And to make things worst, the success of the Rimba Ilmu then would only be seen in thirty or fourty years from then as the plants would have matured and acquired the feel of the real forest!

Now more than thirty years later, the dreams of Professor Stanton comes true and the value of bequithing his expertise to Univesrity Malaya in the form of one of the best natural Botanical Garden in the world
The Rimba Ilmu today is divided into a few specialized areas such as:
1Medicinal plants
2 Palms
4 Mixed forest species
5 Ferns
6 Fruit trees
There are at least a living collection of over 1600 species in the Rimba Ilmu with emphasis on Malaysian and Indonesian species. Important species of plants in the Rimba Ilmu are provided with valuable information on its taxonomic and importance for the benefit of visitors

The Rimba ilmu trail starts with a winding concrete slab pathway leading to the metallic gate that welcomes the visitors into the realm of the Rimba Ilmu. Even while still a few metres out of the Rimba Ilmu you will already be able to appreciate the diversity of plants that lie awaiting for you in the enclosure of the Rimba Ilmu

The narrow trail through the Rimba ilmu is a winding path which meanders though the terrain. Most times the path is shady due to the overhead dense leafy canopy of trees. Spotlights of sunlight that break through the canopy would regularly light up the path.
Sometimes the single path might split into two paths to give the choice to the visitors of areas in the Rimba Ilmu that excites them. There is no worry of getting lost as there are enough signs and maps ti guide the visitors through the adventurous journey of discovery
The realism of the forest habitat built into the Rimba Ilmu is even brought to more realism by the unending sounds of the forest insects such as cicadas and crickets as if trying to outso each other in getting your attention
The feel of the forest is even felt by the increase in humidity of the forests brought about bt plant transpirations which throws molecules of water into the environment.
For the visitors who have never visited a forest, the experience is exhilarating and more memorable by the presence of mosquitoes eager to taste their blood!
The forest trail within the Rimba ilmu is scenic throughout from beginning to the end. The trail often passes through small , shallow streams with crystal clear waters and even a stagnant sago swamp.
It is almost impossible to cover or describe all the plants kept at Rimba Ilmu. For discussion purposes we will cover a few important medicinal and economic species found in the Rimba Ilmu
Before there were modern medicine and hospitals, a lot of people depends on various types of plants for the medicinal purposes. Our tropical forests are a rich source of medicinal plants which are yet to be fully researched and exploited
Most of these medicinal plants contain secondary metabolites such as alkaloids which have strong pharmocologic activities. In the Rimba Ilmu we have examples of medicinal plants commonly used by the locals such:
1 Misai kuching or literally translated means Cat’s whiskers is a plant which is commonly used by traditional medicine to cure diabetes and high blood pressure among others. The scientific name is Orthosiphon aristatus (Lamiaceae)
1The serengan plant (Flemingia strobilifera), a species of the bean alliance (Leguminosae), commonly cultivated in villages throughout the Indian and Malaysian region. A decoction of its leaves is sometimes used in treating rheumatism.
2 Catharanthus roseus, the common Madagascar Periwinkle, contains alkaloids used to retard the progress of leukaemia.
3 Brucea javanica (Simaroubaceae), which finds medicinal use against dysentery and worms.
4 Baeckea frutescens (Myrtaceae) has essential oils used in health tonics and for scenting household preparations.
5 Andrographis paniculata (Acanthaceae), commonly known as hempedu bumi ("gall of the earth"), in the medicinal plant section. The leaves are useful in treating diabetes and high-blood pressure.
In this country palms have a very significant impact on the lives and economics of the people.
Sago plants rich source of sago,
Coconut trees for coconut oil, coconut milk used for Malay cooking,
Palm oil used extensively in cooking industries world wide
Now even more added values are attempted such as alcohol biofuel from sago, and from palm oil

Posted by memcantik at 6:31 AM 0 comments
Labels: botanical garden, rimba ilmu, university malaya
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