Agricultural Technology Development Centre (ATDC) Katumani is a technology development organization under Ministry of Agriculture and Livestock Development mandated to empower and capacity-build farmers and SMEs in Machakos, Makueni, Kitui, and Kajiado counties on various agricultural technologies with the aim of increasing agricultural production. One of those technologies that is readily accessible to farmers and meant to reduce drudgery in the postharvest handling of legumes is motorized legume thresher.
For generations, farmers have relied on backbreaking labour to separate different legumes from their pods. Manual threshing is a tedious, laborious, and capital-intensive activity. However, with a motorized legume thresher, farmers are able to save time, costs, and post-harvest losses that come with manual threshing. Motorized legume thresher has multiple sieves of different sizes to enable the farmer thresh a variety of legumes e.g. beans, green grams, cowpeas etc. It is also equipped with a blower that cleans the threshed product, saving the farmers the mundane task of winnowing.
Major Components of the thresher
The motorized legume thresher consists of feeding hopper, threshing unit, collection and discharge system, fan, and sieves. Since different types of legumes come in different sizes, the thresher incorporates multiple sieves that match the nominal diameter of these seeds.
Figure 1: Motorized legume threshers with multiple sieves
Precautions to observe during threshing
Motorized threshing is a critical operation that if not properly executed can result in seed breakage. For effective threshing, the legumes should be dry to a moisture content of 14-18%. Moisture content beyond 18% lowers the efficiency of the thresher by making it difficult to separate the grains from the pod while moisture below 14% poses the risk of grain breakage. The following precautions need to be observed before and during threshing. One should;
- Familiarize themselves with the operation and safety instructions provided to understand the proper procedures for starting, operating, and stopping the thresher.
- Inspect the thresher before operation: Check for any signs of damage, loose bolts, or worn-out components that could affect safety or performance.
- Wear appropriate clothing and personal protective equipment (PPE): Wear close-fitting clothing, sturdy footwear, and appropriate PPE such as gloves, eye protection, and hearing protection if need be.
- Keep clear of moving parts: Wait until the machine has completely stopped and the power source is disconnected before attempting to clean, adjust, or repair any part of the thresher.
- Avoid overloading the thresher: Overloading can lead to decreased performance and damage of the machine.
- Avoid threshing wet crops: Threshing wet or damp crops can increase the risk of equipment clogging and reduce threshing efficiency. Aim to thresh crops when they are at a moisture content of 14-18% for optimal performance.
Machine output
Motorized legume thresher mounted with petrol engine uses one litre of petrol fuel to thresh 300-350kg/hr of green grams and 70-110kg/hr of beans depending on the variety and degree of vegetative materials. A farmer operating motorized legume thresher for 5 hours a day, with an average cost of one litre of petrol being Kshs 192, will require 5 litres of petrol at a cost of Kshs 960 to produce 1500-1750kg (16-19 bags) of green grams and 350-550kg (3-6 bags) of beans in a day. This is far much cheaper compared to hiring two people at a cost of Kshs 1,000 per day to produce the same quantity in 2 days using manual labour.
Fig 2: Testing of motorized legume thresher
Fig 3: Sensitization of farmers on thresher.
Accessibility of motorized legume thresher
Motorized legume threshers are available at our station and can be accessed by individual farmers or farmer groups following formal requisition through the centre manager. The station also links individuals farmers/ farmers groups to local manufacturers or dealers to acquisition of own machines.
Other technologies offered by station:
Walking tractor and its attachment for land preparation, chopper shredder, manual hay baler, and brush cutter for livestock feed making. The station also has value addition technologies e.g. fruit pulper, vegetable slicer, cassava chipper and honey processing equipment
For more information or inquiries, please reach us at katumaniatdc@yahoo.com.
By Mary Kanda: CEO Agricultural Development Centre.