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Back to nature's way of cleaning
Back to nature's way of cleaning
Biotechnological cleaning and hygiene systems sounds so very high-tech, extremely new, novel and innovative but, in effect, exactly the opposite is true. Biotechnological systems have been used by nature for millions of years. How for instance were the carcasses of dinosaurs, so prevalent in the Mesozoic era, removed from the surface of the earth? By means of biotechnological cleaning systems, in the form of microbes which caused decomposition of the dead animals to occur and ultimately prevented cluttering-up of the earth's surface by such structures. What happens to leaves from the trees when they fall in the autumn? Once again, "Mother Nature's little helpers" are on hand to break down and remove the plant material which is reutilised/recycled by soil dwelling bacteria and fungi.
It is only relatively recently that these systems have been considered for use as cleaning agents in modern day society and their impact is now being felt.
What exactly are these biotechnological systems and how do they work?
Biotechnological cleaning and hygiene systems are enzymic in nature, utilising natural catalysts called enzymes to carry out the cleaning function. Enzymes, being natural catalysts (proteinaceous in nature), speed up the degradation process of organic soils, either converting the soils into smaller units which can be taken up by micro-organism systems in the cleaning environment and utilised as an energy source by them, or converting them into more water soluble species which can easily be removed by washing down with water.
Enzymes will effectively and efficiently break down soils composed of fats, oils, grease, starches, proteins, etc. In itself this is a very attractive propositon, but these systems also offer other extremely important bonuses, one being that they offer an alternative to the extremely dangerous chemical cleaning systems currently used in a number of areas. They can replace/reduce the usage of hazardous, corrosive traditional chemical cleaning products such as:
acidic descalers (hydrochloric acid, sulphamic acid-based products);
alkaline degreasers (sodium hydroxide, sodium metasilicate-based products);
toilet cleaners (sodium hypochlorite, hydrochloric acid-based products);
industrial degreasers (chorinated hydrocarbon solvent-based products);
hard surface cleaners (sodium hydroxide, sodium metasilicate-based products);
acidic drain cleaners (concentrated sulphuric acid, concentrated hydrochloric acid);
and so on.
As suggested earlier the agents which carry out the actual breakdown of soils in biotechnological products are enzymes. These enzymes can be present as free enzymes in formulations or encapsulated within bacteria, which act as tiny living enzyme factories, bio-synthesizing the enzymes needed to break down soils which they come up against, effectively producing a bespoke cocktail of cleaning enzymes for each soil profile encountered. These bacteria, which are non-hazardous, are extremely hardy and can withstand harsh conditions in a "suspended animation" spore form.
Some biotechnological cleaning formulations also contain compatible "softer" chemical systems such as alkaline builders, sequestrants, surfactants to aid rapid soil breakdown. Hence it is possible to have the best of both "worlds", with combined biotechnological/soft traditional chemical components in cleaning formulations.
In order to produce more elegant, sophisticated biotechnological products for the retail market it is possible to incorporate opacifying agents, colour and fragrance, these types of products competing head to head with the well-known branded products we are constantly exposed to in the media.
Owing to the nature of their components biotechnological cleaning and hygiene products have a number of extremely important benefits.
Biotechnological systems, unlike hazardous, corrosive, traditional acidic or alkaline products, will not cause severe damage to personnel if they come into skin contact or are accidentally ingested. These systems are generally extremely specific and will only attack the specific soil type that they are formulated to tackle, they are not rapid acting and can easily be washed off skin or rapidly flushed through the internal digestive tract with water causing no harm to personnel involved.
However, it must be said that biotechnological products may have a detrimental effect on a small percentage of the population (approximately 0.2 per cent) causing allergic reactions/responses when coming into direct contact with the products.
Being based on natural systems, biotechnological systems have no negative impact on the environment following spillage or entry into the normal effluent treatment systems. In fact as opposed to having a detrimental effect on effluent treatment systems the enzymes or bacteria present in biotechnological products will actually reduce the "load impact" on the effluent treatment systems "downstream" by partially breaking down the organic components of the effluent stream in situ as it is transferred to the effluent treatment plant (effectively reducing COD and BOD).
As intimated earlier in this article, biotechnological systems are very specific and will only break down soil systems they are formulated to degrade and remove. They will not damage the surfaces on which the soil has become attached, unlike traditional chemicals which have no specificity and can and will attack substrates causing, in some cases, severe corrosion damage which can have substantial financial impact, reducing the functional life of surfaces affected.
Biotechnological systems are readily biodegradable unlike some of the surfactants and raw materials used in traditional chemical cleaning products. This means that these systems have a substantially reduced environmental impact compared to their chemical counterparts.
Compatible with some traditional raw materials
Biotech systems are compatible with certain "softer" traditional chemical cleaning systems, such as surfactants, sequestrants, alkaline builders, etc. and as a consequence may not be deactivated when coming into contact with products containing these components.
In most cases biotechnological products are more efficient and effective in their cleaning action, producing a "deep clean" effect not merely a surface effect, penetrating deeply into pitted, undulating surfaces, unlike chemical systems which have an effect only on the surfaces they come into contact with. Another important characteristic of biotechnological systems is that they are not "used up" as chemical products are. Once a chemical molecule has reacted with a soil particle or substrate particle it is converted into a different form and is no longer "active", but is "used up" effectively losing its useful life. However, with enzyme systems the same is not true. Once the enzyme has broken down its target soil particle it will move on to another in "continuous useful action", the only constraint on its active life being lack of target soil particles or changing conditions.
Owing to the deep cleaning aspects of enzymic products they effect a multi-purpose action producing a "hygienically positive, clean surface" aiding in preventing bacterial and fungal growth by removal of food sources, also having the added feature of neutralising smells by similarly preventing growth of odour producing microbes.
Owing to the "deep cleaning" action of biotechnological cleaning systems (as described above) it is possible to reduce the frequency of cleaning in many operations, thus reducing product usage and staff cleaning costs. Energy costs can also be cut in many cleaning operations (e.g. food manufacturing plants), where high temperatures are used in steam cleaning and hot wash-down procedures in order to optimise chemical cleaning product functionality. In the case of biotechnological systems, being living systems they function optimally at 40°C thus negating the requirement for expensive heating phases. Biotechnological systems do not damage the surfaces and equipment they come into contact with as do some chemical cleaning products and thus they offer the potential to increase the functional life-expectancy of plant and equipment they are used to clean and reduce costs in terms of repair bills and replacement aspects (e.g. engineering and food industry).
As biotechnological products are effectively "living systems" they require certain conditions to allow them to function optimally and are, like us, affected detrimentally by extreme conditions.
As a general rule biotechnological systems work best at a pH of around 7 which is neutral, they work at temperatures of between 7 and 45°C. As living systems they are deactivated by harsh chemicals such as bleach, acids, alkalis, organic solvents and biocidal agents. Hence it is extremely important that prior to using these elegant systems an educational phase be implemented. Biotechnological systems will be deactivated by strong damaging chemicals, in the same way that we are harmed by them and so it is not possible to mix traditional strong chemicals with biotechnological products.
Those systems which use free enzymes in their formulations can be as rapid in their action as some traditional chemical products; normally, however, longer surface contact times are required for these systems. Where formulations contain bacteria even longer contact times may be required (several hours in some cases).
The active components of biotechnological cleaning and hygiene products are very versatile and lend themselves to standard application methods allowing them to be applied in the same manner as traditional cleaning products.
The use of biotechnological cleaning products therefore offers an alterative method of cleaning which is deemed to be "state-of-the-art", novel and innovative, environmentally positive, user friendly, cost- and energy-effective. These systems must be seen to be "the cleaning systems of the future" and yet they utilise some of the oldest and most effective living cleaning systems known to man, pre-dating man by millions of years.
Norman A. SlaterSenior Partner, EHSP Consulting Group