WAMITAB - Chartered Institution of Wastes Management Recycling and Resource Recovery Questions and Answers

Question 1

A Materials Recovery Facility (MRF) needs to separate aluminium cans from a mixed stream of dry recyclables that has already had ferrous metals removed. Which piece of equipment is specifically designed for this purpose?

Accepted Answer

Eddy Current Separator

Answer

An Eddy Current Separator uses a powerful rotating magnetic field to induce an electric current (an eddy current) in non-ferrous metals like aluminium. This creates a secondary magnetic field that repels the metal, causing it to be ejected from the main waste stream. Trommels separate by size, NIR sorters separate plastics by polymer type, and air classifiers separate by density.

Question 2

The PAS 110 specification is a critical quality standard in the UK resource recovery sector. To what waste treatment process and its primary output does it apply?

Accepted Answer

Anaerobic Digestion and the resulting whole digestate.

Answer

Publicly Available Specification (PAS) 110 sets the quality criteria for digestate produced by anaerobic digestion (AD). Meeting this standard means the digestate is considered a product, not a waste, allowing it to be used as a biofertiliser without waste management controls. The equivalent standard for compost is PAS 100.

Question 3

Which of the following is considered a major contaminant in a paper and card recycling stream that significantly reduces the quality and value of the final recycled product?

Accepted Answer

Grease and food residue from a pizza box

Answer

Grease and food residue cannot be effectively separated from paper fibres during the re-pulping process, where the material is mixed with water. The oils contaminate the slurry and bond to the fibres, causing defects and quality issues in the new paper product, potentially leading to the entire batch being rejected. While other items are contaminants, modern MRF processes are better equipped to remove them.

Question 4

An Energy from Waste (EfW) facility produces two primary solid residues from the combustion process: Incinerator Bottom Ash (IBA) and Air Pollution Control residues (APCr). Which statement correctly distinguishes between them?

Accepted Answer

IBA is the non-combustible material from the furnace grate, often recycled as aggregate, while APCr is the hazardous fly ash captured from the flue gas.

Answer

Incinerator Bottom Ash (IBA) is the bulky, non-combustible residue left after combustion, which, after treatment, is often used as a secondary aggregate. Air Pollution Control residues (APCr), or fly ash, consist of the fine particles and chemical residues captured by the flue gas treatment system. APCr is classified as hazardous waste due to the concentration of pollutants and requires specialist disposal.

Question 5

In the context of household recycling collections, what is a primary advantage of a 'kerbside sort' system compared to a 'co-mingled' system?

Accepted Answer

It generally results in higher quality recycled materials with lower contamination rates.

Answer

In a kerbside sort system, materials are separated by the resident and/or the collection crew at the point of collection. This minimises cross-contamination (e.g., broken glass mixed with paper), resulting in cleaner material streams that have a higher value and are more desirable to reprocessors. Co-mingled systems rely on a Materials Recovery Facility (MRF) for separation, which often leads to higher contamination levels.

WAMITAB - Chartered Institution of Wastes Management Certification Practice Test

WAMITAB - Chartered Institution of Wastes Management Certification Practice Test

WAMITAB - Chartered Institution of Wastes Management Recycling and Resource Recovery Questions and Answers