Low-Cost Incinerator for Cape Maclear, Malawi

Design, Maintenance, and Operation

DOI

Contributors:
- Mosè Peduzzi ORCID logo 0009-0004-6055-3835 author
- Jakub Tkaczuk ORCID logo 0000-0001-7997-9423 supervisor, maintainer, developer
- Elizabeth Tilley ORCID logo 0000-0002-2095-9724 supervisor


Github repository for this page sits here.

1 Introduction

This video presents the construction of a modified De Montfort Incinerator Mark 8A, designed and built between October and December 2023 in Cape Maclear, Malawi. The incinerator presents several modifications compared to the original design 1, e.g., the ash collection drawer 2 and the cyclone separator to filter the flue gases.

The construction of the incinerator is part of a broader project conducted by Global Health Engineering, an ETH research group, which aims to introduce regular waste collection in the township of Cape Maclear, Malawi, ensuring safe waste disposal and minimizing environmental contamination. This incinerator reduces waste volume and makes hazardous waste harmless, emphasizing cost-effectiveness.

2 Incinerator Overview

The incinerator built within this work is a small-size incinerator, composed of a structure of refractory bricks and cement with a metal frame on the top. The interior space is divided into two combustion chambers; the first can be accessed by the operator through a door located at its top, allowing for inserting of a new waste bag. The second combustion chamber and the attached cyclone separator remain inaccessible to the operator and are intended solely for to treat the fumes. The purpose of the second combustion chamber is to reduce carbon monoxide to carbon dioxide through secondary combustion (and combustion time increase), while the cyclone separator allow to reduce the particulate matter (PM) in the fume gasses.

The incinerators can burn about 3.5 kg/h of waste, reaching temperature of 770°C. The mass of the ashes produced by the incinerators represent about 20-30% of total mass of waste burnt.

Figure 1: Modified De Montfort incinerator Mark 8A with integrated cyclone separator in the back and removable ash tray on the bottom of the combustion chamber.

Figure 2: Incinerator during construction.

3 Part List

No. Item Specs Qty. Source Cost per unit (USD) Total Cost (USD)
1 Metal U-Channel L x W x H: 100 mm x 60 mm x 6 m 1 DeeKay 85.29 85.29
2 Angle Iron 30x30x3 mm 6 m L x W x T: 30 mm x 30 mm x 3 mm x 6 m 1 DeeKay 14.71 14.71
3 Metal plate L x W x H: 2400 mm x 1200 mm x 3 mm 1 DeeKay 126.47 126.47
4 Metal tube with a diameter D x L: 75 mm x 3 m 1 DeeKay 46.76 46.76
5 Flat bar L x W x H: 35 mm x 3 mm x 6 m 1 DeeKay 17.35 17.35
6 Heat resistent paint 1 L 1 Valmore Paints 7.47 7.47
7 Threaded Rod D x L: M 10 x 1 m 1 Build Africa 6.62 6.62
8 Bolt M 10 10 Lilongwe 0.12 1.18
9 Washer M 10 2 Lilongwe 0.12 0.24
10 Empty oil barrel 200 L 1 Ndirande market 17.65 17.65
11 Cement bag 50 kg 8 Monkey bay 11.76 94.12
12 Sand 1 ton 2 Cape Maclear 2.94 5.88
13 Bricks (njeli) L x W x H: 10 cm x 17 cm x 6 cm 1200 Cape Maclear 0.03 31.76
14 Armament bar D x L: 10 mm x 12 m 1 DeeKay 11.76 11.76
Total Costs (USD) 467.26

4 Safety Precautions

Always wear protective equipment when working with the incinerator. Goggles, gloves, and closed footwear are essential for protecting the operator’s health.

5 License

The complete design and user manual are licensed under Creative Commons Attribution 4.0 International.

Footnotes

  1. https://mw-incinerator.info/↩︎

  2. J. Van Den Noortgate, D. Taylor, and G. Yannick, Incinerator in Health Structures of Low-Income Countries. Médecins Sans Frontières, 2012. Link.↩︎