Recycling of plastics-New approach to save water and energy

To day's world cannot live without plastics as practically every walk of life is associated with use of one or the other plastic material. Out of the 300 million tons production of plastics of different types world wide, about one third is used for packing,  rest being channeled into a variety of products like tubes, pipes, structural parts, sheets, containers etc. In India more than 40% goes for packaging including that for protecting foods. As they are derived from non-renewable fossil fuels, man must be wondering whether his head-on rushing into massive use of plastics will prove to be a folly, considering that world was using for centuries traditional materials like metal, glass, ceramics, wood etc all of which are readily recyclable endlessly and with relative ease, besides being renewable in nature. Plastics, which are high molecular organic molecules are impervious to water and are not degradable in nature for hundreds of years. Recycling of plastics can be done by just melting it after sorting and cleaning at relatively low temperatures but there is a limit as to how many times it can be recycled as its property is adversely affected after recycling. Conventional recycling involves use of high quantity of water and lot of energy, both at a premium in countries like India. A new technology reported from Mexico claims that the water consumption and energy use can be significantly reduced making the recycled plastic.cheaper. Here is a take on this new development.    

"Mexican startup Ak Inovex has developed a 'Greener' plastic recycling uses no water and only half the energy  At the same time, it produces plastic pellets of equal or better quality,  resulting in an environmentally friendlier process that also promises to be significantly cheaper. Plastic recycling can turn discarded bottles and other scrap into a myriad of useful objects, helping produce anything from polyester clothes to 3D printing filaments and even diesel. However, it is a long, laborious affair that consumes plenty of resources  –  especially water. Among other things, the plastic needs to be thoroughly washed to get rid of impurities, carefully dehydrated inside an oven, and then water-cooled once again as the newly-formed plastic filaments are cut into small pellets. According to Marco Adame, the new method that his startup has come up with can produce pellets of equal or better quality using just half of the energy by getting rid of the need for these temperature extremes, while also doing away with the need for water altogether. The system uses special walls that, on contact, are able to both mold the plastic into the desired pellet shape and cool those pellets at the same time. The energy-demanding dehydration process, which involves temperatures of around 180° C (360° F), had been a necessity so far because, after being washed, the plastic molecules would otherwise attract water to themselves and prevent the plastic from crystallizing properly. Being able to process scrap plastic without water has therefore simplified things considerably. Adame says that using his technique, the same machines are able to process styrofoam, polystyrene and ABS, which together make up about 90 percent of all plastics. The improved versatility would mean less space would be needed for operation."

Limitation vis-a-vis plastic recycling does not lie in technology but logistical problems associated with segregating different plastics from the garbage for channeling them to different recycling systems. There are at least two dozens of plastics in common use and they come to the garbage dump mixed with organic and biological waste and this restricts the extent of plastic recycling to less than 5% of total used through out the world, the figure varying from country to country. Increased use of plastic wastes for energy generation is another encouraging development that will remove more and more of these naturally indestructible man-made material from the environment. Comparing to paper which is recycled to the extent of 80% plastics will have to go a long way to remove the tag it has earned as "chokers" for its role in contaminating oceans and river bodies, bringing about destruction of natural aquatic creatures.

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

Food wastes-Bakery foods most wasted!

Why do people throw away perfectly safe and good quality food without consuming them? Probably a high degree of insensitivity to the sufferings of millions of fellow denizens who have no or little access to food due to economic compulsions. If some of the reports are to be believed the total quantum of food wasted across the world can feed almost 2 billion people, almost 30% of current world population! It is difficult to believe this figure though there is no independent data to confirm or challenge these staggering estimates. In a country like the UK, it is believed that about 24 million slices of bread are thrown way though they were of acceptable eating quality. Across Europe one estimate puts the quantity of food waste at about 90 million tons! Interestingly it appears bakery products top the list of food items wasted followed by pastry items like cakes. Here is a take on this perplexing issue: 

"Bread, biscuits and cakes rank high on the list of food wasted, so to what extent can bakery manufacturers drive environmental progress and help reduce food wastage? Paul Featherstone, group director of food recycler, SugaRich, investigated for Biscuit World. In April 2014, the House of Lords EU Committee revealed startling findings from their 'Counting the Cost of Food Waste: EU Food Waste Prevention' report1. At least 90 million tones of food is said to be wasted across the EU every year.  According to a report into UK food waste published in November 2013 by the Waste Resource Action Plan (WRAP)2, bread tops the list of food thrown away uneaten with the equivalent of a staggering 24 million slices of bread wasted daily,whilst sweet treats like cakes rank high on the list too. Legislative pressures and environmental targets have gone some way to encourage progress. The EU's pledge to halve edible food waste by 2020 is an ever-pressing driver, as is the media's continued scrutiny over unsustainable surplus food practices. Commercial factors have also had a distinct part to play because, whilst some organizations want to demonstrate stronger 'green' credentials to enhance their reputation and uphold their corporate social responsibility, others simply cannot afford the ever-rising charges associated with traditional landfill disposal or anaerobic digestion" 

There could be a logic in this situation where bread and cakes are wasted comparatively in larger quantities compared to others and the reason is that they are high moisture products vulnerable to spoilage, chemical, microbiological and organoleptically. Stale bread may be safe to eat but most people cannot accept it because of undesirable textural changes and reduction of flavor associated with fresh bread. So it is with cakes also. A logical question that follows is how to cut down on this colossal waste and whose responsibility it is to do that? Bakery industry probably will have to innovate further to prevent quality changes perceptible to the consumer so that they are not discarded on this account. On the part of the consumer there must be conscious attempt to buy just enough quantities for home consumption without resorting to storing them for long considering the susceptibility of bread to staling. Another point consumer has to remember is that staling phenomenon due to starch retrogradation is reversible by heat and naturally during toasting bread will regain its quality almost completely. Refrigeration must be resorted to if bread is to be stored for more than 2-3 days to prevent fungal spoilage. There is thus considerable scope to bring down wastage vis-a-vis bakery products if adequate care is taken by the industry as well as the consumer.

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com