Executive Summary

This report was written in response to call for engineering problem-solution proposals. It focuses on the waste recycling technologies that are currently out in the market to combat the generation of food waste and discusses its capabilities against one another. The complication would be the difficulty to handle a overproduction of by-products and the productive use of them. This may result in squandering of by-products which reduces the tendency to use these machines which defeats the purpose of improving the recyclability of food waste.

The objective of this report is to propose to the planning committee of SIT Punggol a more sophisticated system that improves and combines the technologies that are offered in the market currently. The team proposes a solution that allows the waste recycling machine to effectively produce the amount of by-products based on the input of the user. This will effectively provide the sufficient volume of fertilisers and reusable water so as to reduce the potential squander of useful products. 

Personal Statement

Roland, a student from Singapore Institute of Technology (SIT), is currently pursuing his degree in Civil Engineering.
As the amount of food waste increase through the years, Roland is concerned with the waste being put into incineration after food consumption.
He sees the need in supporting the practice of recycling, and applying it into food waste that can be re-use for another purpose.

Thus, together with his team members, their priority to achieve improving the food waste issue and implementing food waste recycling in order to help conserve the environment.

Full Report Draft #1

1.  INTRODUCTION

This proposal has been developed in response to combat the food waste by food consumers so as to convert the disposal into byproducts that benefits the environment.

Singapore is faced with an ongoing situation where vasts amounts of energy and manpower has been used to deal with food waste. Starting from vehicles needed to transport to incineration plants, to the energy used in the boilers to incinerate food waste down to ten percent of its original size. Furthermore, the incineration of food waste comes with the imminent cause of air pollution which negatively degrades the environment.

As Singapore’s population continues to grow, the amount of food disposal has been ever increasing at the incineration site. To counter the issue on the rapid growth in food disposal, my team proposed an idea to improve the situation of food disposal conservation. Since the recycling rate has increased gradually to 14% during the last ten years. Our goal is to implement food recycling machines in SIT Punggol will efficiently add value to the effort of recycling food waste in Singapore.

Singapore’s current application into incorporating food waste recycling is by using food waste on-site waste treatment systems. Currently, in the market, there are various machines such as Westcom, BioHitech and Eco-Wiz. All these machines have the same purpose into recycling food waste into reusable products.
As of now, two waste recycling technologies are being used to produce two different byproducts. However, the organisation is required decide to between the two technologies to implement in their premises. Hence, our solution is to incorporate two of these technologies into a single machine whereby the operator will select the preferred mode for the output of the byproducts. This way, it will generate the flexibility of installing the machine in a variety of facilities.

Evaluating the current technologies of recycling food wastage, would help the planning community of SIT to understand that there are such machines in the current market.Through the implementation of a food waste recycling machine that decompose into two different by-products, it would increase efficiency and flexibility. Finally, food waste can both be recycled into fertilizers and black water.


2.  CURRENT IMPLEMENTATION

In the last 10 years, food waste has been increasing from about 500 000 tonnes to close to 700 000 tonnes in 2016, 2017. This increment of food waste is due to two main factors. The increase in population and commercial activity. Efforts has been taken place to reduce food waste. Starting from the source, food wastage efforts has been carried out in terms of posters to encourage buying what is only needed as food wastage due to expired foods were the main contributors to food wastage. The next effort was to redistribute excess food to food organisations through donations to reduce the need to throw food waste when it passes the date of expiry. The last and least recommend effort would be to dispose waste to waste-to-energy (WTE) plants to recover energy from waste and to reduce them down to 10 percent from its original size to be disposed into incineration plants. Our team feels the need to encourage and focus into recycling food waste as it has not yet been well-established enough in the current market due to certain factors. We believe that through the integration and improvement of existing technology can we only be able to further recycle food waste into reusable products.

Food waste machines are implemented with the main purpose to reduce the dependency of incineration plants and landfills. Currently, there are two different types of food disposal technology that breaks down food waste. One of which, breaks down the food waste into fertilizers which can be used for agriculture and the other produces reusable water which can then be used for watering plants or cleaning of premises.

These machines operate through the breakdown of food waste by micro-organisms in the system. As waste is introduced into the system, micro-organisms start to feed and break down on food particles, ultimately reducing its size. In the chambers, rotating shafts would mix the bio media (which houses micro-organisms) as well as the food waste to ensure homogeneous mix of materials. There is a heating element to provide warm conditions for micro-organisms to thrive. To produce waste water as a by-product, micro-organisms need an aerobic condition and hence, air is introduced through inlets. Food waste would then be broken down till it would be small enough to pass through digester screens. A 2-step filtration system will then be used to remove grease and certain microbials which may cause diseases or fermentation before it is passed off as reusable water.  On the other hand, fertiliser is produced as a by-product through anaerobic conditions. As the chamber is closed and sealed off, waste will first get its water vapour evaporated off which passes through vents. This in turn reduces waste by 70 percent. Micro-organisms will further reduce the volume of the waste to 10 percent of its original volume, turning it into useful fertiliser compost which can be used on green spaces.

The main variance in technology would come between the process and by products they produce but they all originate from a single idea; to reduce the size of food waste through micro-organisms. Clients would have to decide between which machine works best on which specific environment or work place they are in. Most commercial companies prefer the food waste machine to produce reusable water as they do not have green spaces and would prefer to have a full reduction of waste to ultimately reduce manpower. Educational, eco-friendly parties may choose a food waste machine to produce fertilisers as the compost produced would save the company money. The compost is able to be applied on most soil media and hence its versatility encourages more to use the product.


3.  PROPOSED SOLUTION

By putting the two respective technologies together, it will be an integration of technologies into one single system. This way, it will solve hassle effort of the worker as he has to do twice the work instead. In addition, it will be a lot more convenient with respect to the number of times the worker needs to attend to the machine. In turn, will reduce the complication or rather many taskings that the worker has to do as now, they will rely more on the integrated waste recycling machine to do the work for them right from the very beginning. With the accessibility of the functions, allowing the worker to have the ability to select the amount of fertiliser or reusable water to be produced from the food waste. Selecting the mode of output depending on the needs. Loading the waste into the respective input of the machine, fertilizer or liquid. Estimated time will be show on the digital panel of the machine. Overtime, the byproducts will be churned into bits and fine particles. Hence, both byproducts will be ready after 24 hours. Leaving it untouch for a prolonged time, the system will be smart to self initiate a system shut down. This is to greatly save the electricity cost from the power supply.

Waste to fertilizer recycling technology

Waste to liquid recycling technology

3.1  Waste to fertilizer recycling technology

3.2  Waste to liquid recycling technology

Both of these technologies used do have their pros and cons as well. The benefit of compost food waste machines would be the flexibility to install them at almost any place that have a power socket as they do not require drainage. However, these machines will produce compost as a by-product and manpower is still needed to handle them. The main benefit of reusable water food waste machines is the ability to reduce food waste so small that it is able to pass through filter screens. This leaves waste water that can either be reused or discharged into public sewers while passing the trade effluent limits imposed by PUB, ultimately reducing overall manpower. The downside to this machine is that it has to be placed in a vicinity that has an outlet to the sewers, limiting the flexibility of the machine placement.


4.  METHODOLOGY

• Observations made in the F&B outlets during operating hours on quantity of food prepared and waste management.
•
• Conduct interviews the parties involved in this motive
•
• Research on rules and regulations of various F&B outlets
•
• Research on handling of food wastages
•
• Research the amount of food wastage on a typical day ( E.g. Hawker centre on weekends probably more compared to weekdays)
•
• Research on how much of fertilizers/reusable water can be generated for how much of food waste. (effectiveness)
•

4.1  Primary Research



4.2  Secondary Research


• Research on the rules and regulations of operation in the canteen regarding handling of food waste
•
• Interview on targeted audiences.
•
• Research on the mechanisms of the machines being focused on that are currently used in Singapore and find a way to invent a machine that consists both technology
•


5.  CONCLUSION

In conclusion, our team proposes  to implement a  technology which integrates two different types of technology which produces soil fertilizers and reusable water into a single system or machine. By having two different form of by-products, the school can be reassured that there will not be an overproduction of a certain type of by-product. Moreover, the operator assigned to operate the machine will be given the choice of choosing on which particular type of by-product is needed. These by-products can be used around the school’s premises. For example, the soil fertiliser can be used any agriculture around the vicinity and the reusable water can be used to wash the canteen floors or toilets. Based on our team’s research, we will say for a technology such as we proposed, will have an estimated cost of 30,000 to 50,000 dollars. This may be a huge sum, however, statistics have shown that the amount of food waste recycled which are then used on the premises itself, will compensate for the estimated cost of the proposed system.


6.  REFERENCES