In this blog post, we will talk about the recycling issues in I/GCSE Biology. Let's get started! 🐒

In I/GCSE Biology exam, don't forget to remember what organic waste is!

In UK - over 7.6 million tonnes of food wasted !!!!!!

• Do you remember what decay is in I/GCSE Biology?
• Food + drink wastes ➡️ organic – originally come from plants / animals
• Waste decay as bacteria, fungi grow on them
• Most UK waste disposed in landfill sites

1. once organic waste buried, decay organisms can’t grow
2. not enough oxygen for aerobic respiration

• Decay method

1.  methanogens can grow anaerobically
2.  release methane (flammable + global warming)

• Meat waste attractive to pests e.g. rats, councils ask to separate waste e.g. cans, glass, food etc.

Landfill tips vented in a controlled way for many years after tipping has ended, otherwise methane that forms as the refuse decays might explode or create fires that burn below the surface for weeks.

It is also important to remember the following points in I/GCSE Biology!

Manage garden + vegetable kitchen waste

• ➡️ compost heap – waste piled up and microbial decay breaks it down into compost

Councils collect this as green waste

1. make compost in large scale, process called windrow composting
2. needs space + compost material turned regularly (keep oxygen level hug) no special equipment needed
3. Windrow composting - outdoor composting on a large scale

Other councils collect garden + kitchen waste together

1. composting in large containers until meat waste is broken down, process called In-vessel composting
2. In-vessel composting – forming compost from waste plant material within a large vessel in which conditions of temperature and moisture can be controlled
3. Composting complete by using windrow process

Advantage

1. conditions monitored inside containers + correct moisture + temperature maintained
2. The high temperatures kill pathogens + seeds of weed plants
3. Other process ➡️ anaerobic digestion ➡️ the breakdown of dead plant and animal material without oxygen
4. Food waste put into large digesters + air is excluded
5. Methanogens break down material + release methane – methane collected, used to produce heat – process can’t use wood waste because microorganisms can’t break it down
6. In all processes, the solid end materials can be used for soil conditioning (gardens, parks etc.)

References:

1. "The Gifts from Organic Waste", https://static.wixstatic.com/media/0b6b65_c2ab17fc0e2d46a2a83e41d81979db4f~mv2.jpg/v1/fill/w_749,h_562,al_c,q_90/0b6b65_c2ab17fc0e2d46a2a83e41d81979db4f~mv2.jpg
2. "Windrow Composting", https://4.imimg.com/data4/KU/TE/GLADMIN-30459837/d1-500x500.jpg
3. "Pin på Novel", https://i.pinimg.com/originals/cd/65/15/cd6515daaa09ceeb69fa50ceb064133d.jpg

And we're done with this topic! Well Done!

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Drafted by Alyssa (Biology)