Dear Dinesh Joshi

I was working on the Kitchen waste management a couple of years ago. In Jahangirnagar University, Bangladesh a small scale bio-gas plant is running using the kitchen waste. It has created employment opportunity for some people at the same time keeping the campus clean.

In the sense of environmental and human health, organic fertilizers are very friendly, however, due to their slow activation, farmers are reluctant to use. Organic fertilizers break down according to nature’s rules, so they may not release nutrients as soon as the farmers need them.  And nutrient ratios are often unknown, and the overall percentage is lower than chemical fertilizers.

I did a questionnaire survey and the results revealed that farmers want to produce more crops due to the market demand and they do not like to wait. As a result, they prefer chemical fertilizers  over organic one.

To me the main constraint of kitchen waste valorization is  the market  demand. 

Sir,

Thanks for answering. so mass education may be a key role.

OK. 

Some interesting responses to a very pertinent question. There are surely some handicaps in such pursuit. Sorting of waste like biodegradable versus nonbiodegradable waste, hygiene to composted site and nearby, time taken to develop a mature compost since feedstock will be so diverse , group of decmoposers etc etc. You have a point, on-field composting is far more effective than off-field composting..

A very interesting question. Towards end-user (farmers) the quality assurances need to be sound. This implies absence of undesired compounds / contaminants, which can also include biological agents such as possible diseases or weed seeds. In addition, the composition in nutrient content AND plant availability needs to be guaranteed. A possible way of re-assuring end-users can be to set up an independent auditing / labelling system that controls the production process and end quality. 

Please read the attached report which may help you.

Best of Luck!

The constraints for kitchen waste valorization as organic fertilizers is certainly its availability and the time of its decomposition.

Thanks a lot . 

Our colleagues have raised some pertinent points.  Bio 'fertilisers' suffer the fact that it is difficult to achieve a consistent nutrient analysis, thus, mineral fertilisers are favoured where a certain input of nutrient is deemed to be required.  Composted organic waste, once adequately prepared (composted) may be best considered as a soil amendment rather than a specific fertiliser.  Composting in-situ may also increase the risk of nitrogen-drawdown in the short term if applied close to when a crop is to be grown.  I note that you are working with 'digested' material, so these problems will not be so pronounced.  With unfermented material, preparation away from the field to permit adequate turning and mixing may prove to be safer option.  Good luck with your study, as you are addressing an important social need. 

I prepared two pits in kitchen garden in our house. We used full part of weeds, waste of vegetable materials and other crops waste with kitchen waste materials except polythene. These material well mixed and proper maintain moisture than again mixed after 15 days interval. These compost is well organic sources for my kitchen garden and also used kitchen waste materials. If every person can used kitchen waste materials why can create pollution problems like Delhi.    

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4926079/

Thanks Mr. Pollock, Mr. Yaduvanshi , Mr. Himadri, For answering.

I am also wish to research on part degradation, stabilization, drying on site of waste production, and a part of composting in situ i.e. at farm site, which may reduce the load and space constraints at production site, also centralized blending, mixing can possible, and as Mr. Pollock said, we can manage in situ composting, away from crop zone, which may add value than ready compost. definitely need more study.    

Please Throw lights if possible.

Dinesh.   

Every residents should be prepared compost and used for grown pot vegetable, ornaments plant and flowers plant on our roof. All the constraints would be solved. 

This is a topic with multiple aspects:

• Cost effective treatment of organic resources (let us avoid the term waste for a moment) e.g. thermal composting, vermicomposting, ... (to me anaerobic digestion is not a stabilisation treatment)
• Maintaining of soil organic matter and soil functions by replacing organic matter compared to mineral fertilisers
• Risk assessments organic fertilisers versus mineral fertilisers.
  • Heavy metals (in mineral P fertilsiers, versus organic fertilisers e.g. P/Cd ratio)
  • Organics
  • Pathogens
  • Water contamination of ground water and surface waters with nitrate and phosphate from both mineral and organic fertilisers
• Effect on plant growth (yields) short term and long term effects
• Legislations
• Lobbying from industries in both sectors: mineral fertiliser industry, organic waste management industries
• Guarantees? Erik Meers mentioned this. I am not aware that any fertiliser comes with guarantees of plant availability. This depends on so many factors such as soil, immolation, displacement, plants, weather conditions etc. There are some lab test "claiming that certain % is plant available". This would mean a farmer could sue a fertiliser company or lab for not utilised (uptake of ) mineral fertiliser. Think of  the floods in India right now - guaranteed plant available mineral fertiliser?
• Social and cultural acceptance. Most cultures probably prefer organic residues of mineral fertilisers. 
• Political decisions already prioritising organic fertilisers over mineral fertilisers such as: 

REPORT FROM THE COMMISSION TO THE EUROPEAN PARLIAMENT, THE COUNCIL, THE EUROPEAN ECONOMIC AND SOCIAL COMMITTEE AND THE COMMITTEE OF THE REGIONS on the implementation of the Circular Economy Action Plan

• CO2 footprint. Definitely a big plus for organic fertilisers.
• Water conservation 

In my opinion we need to balance organic and mineral fertiliser application. Mineral fertilisers work best in soils with a high "natural" soil fertility meaning good soil structure and high SOM content. Trials on pure sand with mineral fertiliser application are not published by the industry for a good reason.

The question I am asking is:

How much longer can we allow to landfill or incinerate organic resources such as kitchen wastes and not return those to soil?

If we concentrate on finding regional solutions where farmers and communities work together we will be able to utilise more organic resources. If for example farmers are processing (composting, vermicomposting ,...) kitchen wastes as part of their farm management system they will control the quality on a much higher level than an commercial composting business might be able to do. Waste management versus resource management.

Happy to discuss this further and to receive critics.

Regards Michael

Please have a look at these PDFs..

Thanks Lot Mr. Michael,

For your detailed answer, most of points are relevant and factual.

I am ensuring for real investments of efforts you made to answer me.

For a centralized industry scale, the insurance/certification/labeling is quite possible in ref of today's technology availability.

In India, such up scaling may take some time.

In reference of decentralized processing, the space and time required to reach at the end product with defined finish and quality, at every unit, it will be big question as of now.

To address it, we should think for part processing of waste at a source, at a defined stage. depending on the desired product expected we can design the process.

For example - Sir, I checked your profile, there is lot of work for vermicomposting,   

Can we use degraded/Hydrolyzed- and thermo-oxidized/ dried organic substrate from different sources and collected material could be used for any different centralized unit for vermi/thermo composting or on field composting.

I think, the processing in this way can cut down the transport cost/ difficulties @ 70% and the quality norm adherence could be possible.

I am more interested your answer in reference of vermicompost.

Waiting for Your reply.

Regards,

Dinesh joshi.

Thanks lot Anoop Kumar Srivastava sir,

Noted all three publications, will be helpful for me.

Thanks, 

Dinesh.

Thanks sachin, for adding valuable information.