Arpil 2011

By: Steve
There are lots of elements for, and even more in opposition, to leachate treatment by coagulation. Well before doing it, it'll be necessary that you should know and comprehend these pros and cons. This information is intended to inform you about the main advantages and disadvantages regarding leachate treatment by coagulation. You need to read this to the end, to help you to make the decision that is right for you.

Pros: Arguments In Favor Of leachate treatment by coagulation

1. Just as for any contaminated water it is certainly possible to add a coagulant to landfill leachate and remove a large proportion of the solid material in suspension, and colloidal matter as well.

2. This will reduce the BOD, COD and suspended solids which in itself isn't a bad thing

One other good cause for leachate treatment by coagulation is that by reducing the BOD, COD and suspended solids the liquid will look less contaminated. This delivers the additional benefit of possibly complying with some discharge consents in some rare cases.

But that is the pros of leachate treatment by coagulation. There exists a dark side as well. Here's a discussion of some of the cons.

Downsides: Reasons Against leachate treatment by coagulation

1. After coagulation, sanitary landfill leachate will still be far from safe to discharge to the environment.

Should you discharge this effluent into a watercourse after leachate treatment by coagulation, it may possibly have the impact of causing injury or death to the living organisms in the watercourse due to the presence of dissolved contaminants still in the leachate after treatment by coagulation, which will include a dangerously high concentration of ammoniacal nitrogen ("ammonia"). That is without doubt not a good thing. It could be enough reason for avoiding doing it at all.

2. In fact leachate treatment by coagulation will have removed much of the organic content which would otherwise have been able to support the micro-organisms in a biological SBR type nitrification leachate treatment system which would be able to remove both the solids content and the ammonical nitrogen ("ammonia") making the discharge safe to discharge to as watercourse (stream or river), subject to agreement of a suitable discharge consent with the local environmental regulator.

3. Leachate treatment by coagulation is also expensive due to the cost of buying the coagulant chemicals

The final justification in avoiding leachate treatment by coagulation is that the coagulant chemicals themselves must be disposed of and this will cost money, and if the coagulant is classified as a liquid it may not be permitted to dispose of it into the original landfill.

The use of a suitable biological treatment is vastly preferable to leachate treatment by coagulation in almost all cases of sanitary leachate treatment. I strongly urge everyone to consider this point seriously, since if ignored it might lead straight away to adopting a costly mistake if you decide to carry out leachate treatment by coagulation anyway.

And so that's that. There's the actual advantages and drawbacks of leachate treatment by coagulation. It may not be suitable. It usually isn't suitable. You ought to now consider the points made above and decide if it is really best for you. Hopefully your final decision process has been helped  by the pro and con info presented here. 
Source: http://leachate.co.uk