Leachate Treatment in India

Image by Sustainable sanitation via Flickr

The continuing poor management of landfills in India is a disgrace, so it is no surprise that although we have seen evidence that there is growing interest in the scientific application of good leachate treatment practice in India, it would seldom be possible to apply it, given the unscientific way in which so called "landfills" (dumps?) are currently engineered and managed.

The following is an extract from an article on 24 April of this year (this month) on which I rest my case, since it is based upon the wealthy capital city of the nation:

Delhi government calls its three garbage dumps at Ghazipur, Okhla and Bhalswa landfills. In reality, they are far from what a landfill should be. These are monstrous trash mountains, including hazardous waste, leaching out toxic liquids and emanating noxious fumes. Thousands of scavenging birds swarm over them as they grow larger every day.

The situation could have been different had the corporations given more thought to managing them. Ask any waste picker who scavenges on these dump yards about why this waste could have been a treasure...
...there are hundreds of waste pickers who pick up whatever they can without using masks, gloves or any other protection. Some even tie a magnet to a long stick to pull up metal objects.
 Credits: Capital dumps a fortune at its landfills - Times of India
 

In my opinion the provision of proper waste disposal facilities should be on the very top of the agenda as any nation industrializes and becomes more wealthy. If India cannot devote just a small amount of it additional wealth which has been accruing at a historically uniquely rapid rate for more than the last ten years, then it is a failing state.

To deny pickers the ability to make a living can be an evil, but so many other nations (including many of lesser wealth) have found a way to recycle waste in a way that provides jobs for the local community without recourse to the life threatening and certainly extremely unhealthy practice of "picking".



At the same time, it has been possible to provide reliable leachate treatment and disposal once the landfills are properly managed and built in accordance with good sanitary landfill practices as have been acheived in the majority of nations around the world.

Providing successful leachate treatment plant designs in India, for the old existing dumps is an impossible task. That is because the prediction of leachate quality is rendered from scientific capability to a matter of guesswork by a lack of data and controls, and this is made even worse by India's monsoon climate which means that any leachate treatment plant needs to be able to run at almost no flow in the dry periods and very quickly at the start of each monsoon be able to treat it's maximum design flows.

As the most effective, and lowest cost forms of leachate treatment rely on biological processes and these cannot be quickly switched on therein lies another problem for leachate treatment in India.

Then finally, any leachate treatment plant designer for Indian landfills will discover that the water quality that the Indian government's own rules require the leachate to be treated to, are as strict, or require higher water quality after treatment, than even many authorities require in the wealthiest industrialized nations.

Unfortunately, waste management and especially landfill methods don't seem to get any better in India, despite increased wealth. They won't be able to do so, until the central Indian government revises the rules and makes them realistic, less strict but much better value for money, and appropriate to what the municipalities can afford to spend.

The 80/20 rule should be adopted, at least to start with for all future leachate treatment projects because by reducing the specifications for final water quality and using innovative solutions Indian landfill operators should be looking to spend 20% of the cost they are being quoted currently for leachate treatment plants for 80% of the treatment quality, and that treated quality would be good enough for the local rivers for the health of the rivers to which the leachate plants discharge, and for those using the water from them.

Leachate Treatment Plant Design

Leachate Treatment Plant Design strategies can vary quite considerably because the individual requirements for leachate treatment on each landfill site varies site by site, and through the life of each site. The starting point for any Leachate Treatment Plant Design is always to establish the strengths, composition and volumes of leachate and predict those into the future at least for the initial design life of the leachate treatment facility proposed. The expert skills available from the Leachate Expert website www.leachate.co.uk can assist you in the specification, design, build, installation and commissioning of the most appropriate solution for your site. Within our expertize is also the operation and maintenance of the plants designed by the "Leachate Expert".

Process Design and Implementation - Based on a minimum of information we will work with our clients to provide a practical and economical process design which will then form the foundation of the project. Each project engagement can range from providing feasibility studies, design layouts and process flows, project management, specification, HAZOP’s, P&ID’s, landfill products and plant support.

Leachate Treatment Plant Design is evolving, and will continue to do so as modifications in landfill practices continually add the higher polluting risk arising from sanitary landfill leachates at many landfill sites. Historically, and up and until the early 1970′s, sites for the disposal of domestic wastes were normally small and provided for local waste disposal needs only, each serving a fairly minimal geographical area. Controls applied by regulatory authorities were very basic. These sites were also characterized by reduced input rates, high ash content of wastes from open fires and at the site, combined with the low densities of uncovered wastes which allowed all the waste to continue to gain access to air, and offered a level of negative environmental effects that were typically only locally felt and restricted in severity.

How Does a Modern Landfill Work?

In those days there was little or no Leachate Treatment Plant Design, because smoke, flies and vermin, combined with iron-staining and developments of fungi and micro-organisms in neighborhood streams, were generally tolerated as the acceptable cost of waste disposal. However, everything has changed now, and in most nations the savings from disposal of domestic wastes in what were no more than un-engineered and largely un-controlled “dumps” or “tips”, are considered not worth the environmental damage they do.

Now Leachate Treatment Plant Design is a specialist and highly technically sophisticated subject due to the high strength of modern leachate, and in most countries (unless pre-sorting removes a high proportion of putrescible waste) there is still a a continual increase in wastewater strength. Also, in recent months the volume of wastewater generated at many landfills, due to a wet winter, has exceeded the treatment capacity, resulting in an increase in wastewater being hauled to off-site disposal. To eliminate hauling, and meet more stringent discharge standards from the local POTW a new or revised Leachate Treatment Plant Design may be needed.

The Leachate Expert at www.leachate.co.uk is involved in the evaluation through design and construction of new and better (lower cost) leachate treatment plants. Initially, The Leachate Expert will evaluated plant flow and wastewater quality data to determine the required capacity. The Leachate Expert then prepares a management plan to address the different scenarios available to the site for leachate wastewater disposal. These scenarios investigated usually include: (1) pretreatment and discharge to either a public sewer, (2) or the landfill (i.e., recirculation), (3) complete treatment and reuse on site; and complete treatment and watercourse discharge.