Profile: DADTCO – Small-scale processing for the cassava revolution in Africa
Introduction
The Blog has recently
launched a new section about small-scale biorefining, a platform
to promote small-sized biorefinery concepts and highlight their importance for
the bioeconomy (it is complemented by a LinkedIn Group to share
information and experiences). One of the resources available in the section is
a list with references of companies and projects related to this field. This
list will include a short overview and a link to a monographic post (profile)
featuring in detail the company or the project. This post about Dutch AgriculturalDevelopment & Trading Company BV (DADTCO) is the first of the series.
The company
Web page: https://dadtco-philafrica.com/.
Twitter:
@dadtconl.
Facebook: Dadtco.
DADTCO is a social
enterprise pursuing poverty alleviation with entrepreneurial zeal, business
methods and innovative courage. It was established in The Netherlands in 2002.
It has its support office in that country and local offices in Nigeria,
Mozambique and Ghana. Their stockholders believe that robust economic
development in Sub Saharan Africa (SSA) should come from the establishment of
private businesses that deliver sustainable and profitable high value end
products, whilst directly and tangibly improving the health, living and income
standards of the population.
Cassava is the
major starchy food crop in SSA. Africa is the world’s number 1 cassava producer
but has not developed any cassava processing industry because the very
perishable cassava roots need to be treated within 24 hour of harvesting.
DADTCO has implemented an innovative small-scale biorefining technology that has
changed dramatically the way cassava is perceived, grown and processed in
Africa. Together with its partners covers the whole cassava value chain: agricultural
production with smallholder farmers, input supplies, processing and the
marketing of the final product in local and international markets. Let us know
more about its process concept and technologies.
Concept of small-scale and mobile processing
DADTCO invented a
mobile cassava processing factory able to transform at village level cassava
roots from smallholder farmers into food grade cassava cake or cassava starch
flour. This breakthrough technology bridges the gap between farmers and large
food companies. The company’s mobile cassava starch factories process fresh
cassava on-farm or nearby, instead of attempting to transport the watery
perishable crop over long distances to a central factory.
The mobile
small-size concept overcomes four main obstacles to the commercialization of
cassava across Africa: the high water content of the roots (65%-75%); the rapid
perishability of the roots once harvested (must be used within 48 hours,
preferably 24); its bulky and irregular shape; the wide scattering of
smallholder farmers.
This technology
consists of several mobile processing components that will be descripted in the
next section. DADTCO has developed two scenarios in which to use the different
units.
- Scenario 1: A split processing solution.
The cassava roots
are processed in situ in the cassava growing areas within 24 hours into a
stable and easily transportable intermediate product with a long shelf-life.
This intermediate product is called Cassava Starch Cake (CSC). The CSC is then
transported either to DADTCO’s central flash dryer or an existing cassava
starch plant for further refining.
- Scenario 2: A
fully mobile solution.
The cassava roots
are processed in situ in the cassava growing areas within 24 hours into a final
product, Cassava Starch Flour (CSF). In this case, DADTCO adds a mobile drying
unit to produce food grade cassava starch flour on site. The mobile plant will
move three times per year to different cassava growing areas.
Figure 1. Two
scenarios in the concept of small-scale and mobile processing of DADTCO
(extracted from DADTCO web page)
Technologies
DADTCO’s mobile
process consist of three parts: AMPU, MRU and dryer.
AMPU (Autonomous
Mobile Processing Unit)
The AMPU processes
fresh cassava roots into cassava cake. The whole mobile process is centered on
a high speed rasper. This rasper is the smallest size technically possible
machine while still being capable of releasing 98% of the starch granules in
the roots. The rasper mechanically rips open the cell walls to release the
starch. The lower the percentage of released starch, the higher the starch
losses and subsequently financial losses.
Figure 2. AMPU
sketch (extracted from DADTCO web page)
MRU (Mobile
Refinery Unit)
The cassava cake
coming from the AMPU is refined in the MRU to produce CSC. This unit, which fits
in a 20 ft container which is based on its own dedicated chassis trailer, allows
the extraction of cassava fibres from the cassava cake. The MRU and the AMPU have
been designed to re-use water as much as possible from within its own process.
Figure 3. MRU
sketch (extracted from DADTCO web page)
Processing capacity per hour
|
4 - 5 metric tons of cassava roots
|
Processing capacity per year (depends on daily
operating hours and shift configurations)
|
30,000 metric tons of cassava roots
|
Production capacity per year (depends on daily
operating hours and shift configurations)
|
15,000 metric tons of CSC
|
Flash Dryer (Scenario 1)
Its principle is
simple. Very hot air (180°C) is sucked and mixed with the CSC inside a very
long pipe up to 40 meters high and 1 meter in diameter. The CSC is passed
through the pipe very quickly and is dried to CSF with about 11% moisture. The
CSF and remaining air are separated from each other in a very large cyclone. The
CSF is cooled down to ambient outside temperature and, subsequently, sieved off
to mill down to less than 200 micron. The fraction consists of relatively large
cassava fibres can be used in the production of chicken feed, soil improvers or
even mosquito coils.
Production
capacity per year
|
30,000 metric
tons of CSF
|
Mobile Dryer (Scenario 2)
It is built in two
40 ft containers and the drying takes place in a fluid bed system. The bed of CSC
is supported by a cushion of hot air jets. The method achieves intimate mixing
without mechanical damage.
Processing capacity per day (two shifts per day
basis)
|
48 metric tons of CSC
|
Production capacity per day (two shifts per day
basis)
|
24 metric tons of CSF
|
Production capacity per year
|
7,200 metric tons of CSF
|
Products
CSC is a semi wet
cassava paste that contains: 50% water, 49% released starch (98% on dry matter
basis) and 1% fibres (1.5-2% on dry matter basis). It is packed in 20 kg
plastic bags and has a shelf life of one year. The CSC can be transported to a central
plant for further processing into an array of high value end products:
- CSF. It is a
very white flour that contains only 1.5-2% fibres and 98% starch.
- Cassava starch.
- Cassava based
syrups (maltose, dextrose and fructose).
- Modified
starches (used in food preparation).
- Sorbitol
(component in toothpaste, sweetener and humectant in cosmetics).
- Bioethanol.
- Beer, snacks and
other foodstuffs.
Projects
Mozambique and
Ghana
DADTCO’s business
model has already proven successfully with SABMiller (currently, it is owned by
AB Inbev), replacing imported malted barley with cassava
starch in Impala beer in Mozambique and Eagle beer in Ghana. The farmers have
experienced significant improvements in their livelihoods as a result of
participating in the beer supply chain. Key to this success was DADTCO’s system
of employing field mobilizers. The mobilizers coordinate harvesting times with
smallholders to ensure farmers harvest only when there is sufficient demand
from SABMiller for their crop. The company runs 2 AMPUs in Mozambique and 1
AMPU in Ghana.
Nigeria
In Nigeria, DADTCO
transforms the cake into high quality cassava flour. This can replace up to 10%
of wheat flour in bread and can be used as a substitute for wheat flour in
biscuits. And the direct benefit is reducing the dependence on wheat
importations. The government has mandated that flour must contain at least ten
percent of cassava flour, opening a new market for DADTCO. The company runs 9
AMPUs in the country (3 in Taraba State, 3 in Osun State, 3 in Rivers State).
_________________________________________________________________________________
REFERENCES
1 www.dadtco.nl (accessed on 1st April 2017).
2 The Rockefeller
Foundation: “Reducing Post-Harvest Loss
through a Market-led Approach”. May 2015.
3 “Mobile processing units unlock cassava
markets in Africa”. Appropiate Technology, Vol. 42, No 1.
4 “Creating the Cassava Revolution”. DADTCO
presentation.
