Frequently Asked Questions

1)  I have a business in NSW. When I use Kleen Sweep to absorb an oil spill, can I dispose of the used absorbent into regular garbage?


In NSW, disposal of used oil absorbents is governed by the NSW DECC Waste Classification Guidelines and General Immobilisation Approval 99/06 which pertains to the disposal of absorbents having absorbed C10-C36 petroleum hydrocarbon products (ie: sump oil, diesel, etc..).

The Immobilisation Approval does not specifically recommend certain absorbents over others.  However, it does set minimum absorption criteria (1:1) which effectively eliminates all clay sorbents such as zeolite, DE and kaolin clays from being used and then disposed into regular garbage (they must go to restricted or hazardous waste landfills).  Pads, be they natural or synthetic easily meet the IA 99/06 criteria.

Specifically, regarding Enretech sorbents, their disposal can be summarised as follows:

1. Enretech absorbents can be used to clean up various oil spills and can be thrown into regular garbage.

2. The only thing that you must ensure is that you use enough absorbent so there is no free liquid in the waste bin and that the waste is contained in a bag.  Sometimes, when using pads, they can absorb oil and over-saturate, releasing oil later in the waste bag.  Add an extra pad or some KleenSweep to the bottom of the bag and this will take care of any extra oil which might get released.

3. The disposal of used oil absorbents is in accordance with the NSW DECCC General Immobilisation Approval 99/06.  However, please note that you are only allowed to dispose of C10-C36 petroleum hydrocarbons (ie: sump oils, hydraulics, etc..).  You are not allowed to use this system to dispose of any Dangerous Goods (ie: petrol), or other Special Wastes (ie: PCB’s chlorinated solvents, pesticides, etc..).


A more detailed explanation of the NSW DECC Waste Classification Guidelines and General Immobilisation Approval 99/06 which pertains to the disposal of used absorbents, can be downloaded from our Technical Downloads page.

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2)  I am not familiar with your products. What is the difference between KleenSweep and Remediator?


For cleaning up spills on hard surfaces involving petroleum hydrocarbons and other oil based liquids, the best product to use is KleenSweep.  It contains a sweeping agent and a dust suppressant so that it's easier to use in this application.  KleenSweep has been extensively tested to various standards and has been proven to not leach out its absorbed hydrocarbons.  Every sorbent product claims this, but we have the 3rd party test data to prove it.  KleenSweep can also be used for cleaning up spills involving water-based liquids, and this would include neutralised (or partially neutralised) acids.  Obviously, leachate tests do not apply here.  Refer to the summary list of all tests conducted.  Original lab reports are available upon request.

For cleaning up spills on soil or gravel involving petroleum hydrocarbons and other oil-based liquids, the best product to use is Remediator.  It is a bioactive powder which is tilled into the contaminated soil and which accelerates the bioremediation of the hydrocarbons.  Remediator can treat the contamination in-situ or the contaminated soil can be taken to a biofarming operation where the soil is treated ex-situ and Remediator is applied there.

Both KleenSweep and Remediator are made from 100% organic celluloses and other biodegradable compounds.  Neither product will interfere with a viable landfarming operation.  In fact, they will benefit the system.  Refer to product info sheets for KleenSweep and Remediator, as well as the standard Remediator Application Protocol.  All Enretech products can be purchased via our extensive range of agents and distributors.

 

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3)  What is the scientific evidence that KleenSweep holds the product it absorbs, preventing it from releasing and re-contaminating the site? In this situation, what makes KleenSweep better than other sorbents?


The main problem with many sorbents is that they will release their absorbed liquids in a short period of time (some after a few minutes) – either under their own weight or when washed with rainwater.  There are 2 methods which test this: USEPA 9095 (release under its own weight) and USEPA 1311 TCLP (release from washing).  The method which tests this release from washing is called the "leachate test" and there is a standard USEPA test method called USEPA 1311 TCLP (Toxicity Characteristic Leachate Procedure).  There is also a modified version of USEPA 1311 in Australia Standards.  USEPA 1311 simply is a method where a given material is washed with a set amount slightly acidic fresh water.  The water that comes out the other end is called 'leachate" and is collected and further analysed via assorted different GC/MS methods.  Since the 1311 TCLP test was designed for determining the correct disposal of wastes, the analysis of the leachate focuses on those compounds which would deem a waste to be unsuitable for general landfill and would then have to be discarded to special (scheduled) landfill sites.  Thus, the subsequent GC/MS test methods look for heavy metals, halogenated solvents and certain pesticides.  Note that the GC/MS test methods do not test for petroleum hydrocarbons as this is not a standard criteria for waste management.  Petroleum hydrocarbons (PHC) and many other compounds in waste are tested using other methods, but the standard USEPA 1331 TCLP (SW-486) does not test for PHC.

Now, we have noticed that a large number of competing sorbents on the market in Australia claim that their product has 'passed' the USEPA leachate test.  Since USEPA 1311 is a method and not a standard, there is nothing to "pass" or "fail".  We have also noticed that many of these products also claim to have tested their products to the USEPA landfill standard called SW-486.  However, upon closer examination, we found that in some cases, the sorbent leachate was tested without the sorbent having absorbed anything.  And in other cases, when the sorbent was in fact used to absorb a petroleum hydrocarbon (ie: diesel), then "passing" the SW-486 leachate standard was so great surprise since the standard does not test for PHC !

Kleen Sweep has been tested using USEPA TCLP 1311 method and the leachate tested specifically by GC/MS for PHC.  These tests show that Kleen Sweep encapsulates the absorbed PHC tightly in its fibres and thus has very low levels of PHC in the leachate.  We also tested a sawdust-based sorbent as well as a zeolite product in the same manner.  Both of these sorbents showed significant PHC in their leachate.  Test results are available form Enretech upon request.

 

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4)  I have heard that, as it is a natural material, an organic sorbent will biodegrade. But as it biodegrades, the hydrocarbons are re-released as a pollutant. Would this be true?


There is an old argument which says that organic sorbents will biodegrade quickly in landfill, and thus release their absorbed petroleum hydrocarbons into the landfill.  We have never seen any data to support this theory and believe the argument is in fact invalid for the following reasons:

  • The degradation rates of PHC (petroleum Hydrocarbons) and cellulose are different.  Literature states that most PHC's degrade much more quickly than celluloses.  Landfills are typically anaerobic environments and after 40 years, you can still find celluloses present (ie: newspapers that are still legible).  There are no signs of PHCs.
  • Assuming that cellulose did degrade more quickly than PHC's, then how does an oil-coated cellulose fibre degrade from the inside out?  That is, how does the cellulose inside degrade, when it is covered in PHC - without the PHC degrading first?

Ironically, the sorbents that do not biodegrade (ie: clays and polypropylene) release the most PHCs via leachate and when under pressure in a landfill environment.  Polypropylene sorbents are actually designed to release their absorbed PHC's under pressure.  It is this re-release in landfill (usually via leachate) which is now considered by most waste authorities to be undesirable and to be prevented.

Re-release of absorbed oil is a function of re-agglomeration of the oil within the fibre structure (via attractive forces, viscosity, etc.) and occurs at different rates for different types of cellulose materials.  The Ghalambor Report on Sorbents reports on the various rates at which all organic sorbents tend to re-release some part of their absorbed PHCs.  To our knowledge, KleenSweep does not re-release PHCs and this is supported by the Ghalambor report which found that cotton was the best performing of the natural cellulose fibres.

 

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5)  Have you any details/tests on the effectiveness of Kleen Sweep on blood/faeces/urine, and the disposal thereof after absorption? If it is suitable for disposal on landfill after hydrocarbon absorption, would the same then apply for medical waste?


Kleen Sweep can be used quite effectively for cleaning up body fluid spills, but we make a specialty product called BettaClean which works even better.  BettaClean is available in a sachet as well as an entire kit.  It is particularly effective on vomit as it is designed to kill a lot of the odour.  BettaClean has an absorbency of around 200% with water-based liquids (ie: 100g BettaClean can pick up around 200mL of water).  Refer to the BettaClean instruction card and flier for more details.  By the way, all medical waste is usually incinerated, so landfill degradation is usually not an issue.  Make sure you use a waste contractor suitably licensed to handle and transport biohazardous waste.

 

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6)  We use a solvent-based degreaser. Can we use this with Enretech-1 to lift oil and diesel stains from concrete pavers and from a large bitumen area?


I have reviewed the MSDS you sent for Jasol EMULSO.  From what I can tell, after reading through the data sheet, is that it looks like it could do a good job of lifting the oil-based emulsion from the pavers.  However, due to the high pH of the product (even when diluted down), I think it would be toxic to the bacteria in Remediator.  The small amount of d-limonene will have some toxic effect as well, as d-limonene has a high aquatic toxicity.

The process of lifting the stain and absorbing is a sound strategy.  Instead of Remediator, consider using our standard floor sweep absorbent "KleenSweep".  It will do the same job as Remediator, but it does not contain oil-degrading bacteria or nutrients.  It will however do an excellent job of encapsulating the oily liquid it has absorbed and will not leach.  If you wish to compost the resulting solid waste generated from this process, you'll need to lower the pH of the solid mixture (absorbent+Emulso+emulsion) down to below pH 10.  To do this, you can use mild acids such as acetic (vinegar) or phosphoric to do this safely.  If it's too alkaline, then it will probably not compost well.  Also, check with your local waste authority before disposing as it may be too alkaline to go into solid waste (regular garbage).  Lowering the pH may also allow disposal to regular garbage.

You can still use Remediator to clean the emulsion stain, but you'll first need to lift the emulsion out of the pavers.  You can try using a kerosene-based degreaser or a more neutral pH water-based degreaser.  However, you cannot leave the Remediator on the pavers for too long as it needs moisture to activate the "bugs" and is best removed to a biofarm or compost bin for treatment.  I think your best option to get the pavers clean is to lift, absorb & remove, as previously discussed.

 

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7)  When using Remediator to bioremediate contaminated soil, what is the ratio of ERT-1 to soil that you need to apply?


The ratio of Remediator to soil is between 1-2 bags per cubic metre of contaminated soil.  The amount will vary depending on how contaminated your soil is and how well you can mix the Remediator into the soil (ie: clay soils are difficult).  As a rule, if you have sandy/loamy soil and contamination less than 40,000 ppm TPH (4%), you can probably use 1 bag per cubic metre (or assuming contamination to 200mm deep, 5 square metres of in area).  While applying Remediator, always make sure that you add lots of water.  Refer to the generic Remediator Application Protocol for more details, or contact the Enretech Technical Manager who will work with your project specs and design a suitable protocol.

 

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