In the next series of the special project ProDrying for Elevatorist.com, we tell about the experience of drying niche crops. One of the most common of them – peas. The nuances of drying this legume were shared by the specialists of the “Volnogorsk Elevator” of G.R. Agro.
Experience of the Volnogorsk elevator
Volnogorsk elevator accepts 2-5 thousand tons of peas per season. In the total mass of cereals and oil seeds that pass through the elevator, this is a small share, but they work very “gently”with the crop here.
The whole process of working with peas at the elevator begins with determining the quality of the imported batch. In laboratories, tests are carried out for basic indicators, for peas — this is moisture and debris.
In order to determine the contamination of peas, the elevator laboratory performs a standard procedure — disassembly of the hitch on a collapsible board. But the humidity of peas on the” Volnogorsk elevator ” is determined according to Gost using a drying cabinet.
Ground pea beans are dried in a drying cabinet. After that, to calculate the difference in the weight of the hitch before and after drying, the result is converted to a percentage.
According to the head of the PTL “Volnogorsk elevator”, peas, depending on the purpose, as well as the color of seeds, are divided into types and subtypes.
There are two types of peas: food and fodder. In turn, food can be of two subtypes-yellow and green.
“In each subtype, there should be no more than 7% of the second type. If this is a subtype of green peas, then there should be no more than 7% of yellow peas, and vice versa. But feed peas in food should not be more than 1%, otherwise automatically these food peas go to the feed class,” the expert explains.
According to her, when working with peas, it is very important to correctly determine the contamination of the crop. The most dangerous of all pests for peas is brushes, or pea seed. The larva of this beetle eats out the inside of the pea, leaving a shell. It is impossible to determine the infestation of this pest only visually, so in the laboratory, when conducting tests for weeds and infestation, the pea suspension is cut using a scalpel. Thus, the number of infected seeds is determined. Another pest of peas is the Pea moth, or leaf worm. She eats peas from the outside. According to the requirements for export batches, there should be no infected legumes, so the laboratory carefully monitors this indicator.
“The difficulty of detecting a latent form of infection and damage is that it takes a long time. Cutting 100 grams of peas is very long and not so easy. And if, together with peas, the elevator accepts other crops in parallel (the elevator can simultaneously accept three crops, approx. Ed), then, of course, this adds to our worries. But we are coping with these tasks,” says Natalia Halepa.
As for impurities, according to the head of the PTL “Volnogorsky elevator”, seeds of datura, Vine milkweed and other quarantine weeds are often found in their Dnepropetrovsk region.
Before drying at the Volnogorsk elevator, peas are cleaned. Large impurities are selected and if there are very few-small weed impurities of quarantine weeds.
“If you come across datura seeds, then you can select them with a sieve with a cell size of 3-3.5 mm. If you put larger sieves, broken and small peas will get into the waste along with Datura. Therefore, if we determine a large share of datura in the batch (more than 1%), we try not to accept such peas. Everything is according to Gost,” explains the head of PTL.
If the blockage is within the normal range and there are no quarantine weeds, then the elevator uses upper sieves with cells of 10.0, lower sieves with a cell size of 2.5.
The number of passes depends on the garbage. If the weed is up to 5%, the peas are peeled at a time. Large weeds are removed in two passes.
“As a rule, peas come to us slightly wet, so we cope with cleaning before drying. But if the peas are very wet, then you will have to clean them twice. Although in our region this is nonsense, because, as a rule, peas go dry or slightly wet. In one pass of drying, we have time to dry it, in one pass of the separator we have time to clean it before drying,” says Alexander Krat, director of the elevator.
He adds that wet peas are easier to fake, they are not so injured and do not crack.
“On one of the working towers, we have installed BSH — 100 separators in a cascade — one above the other. That is, if you need a double part-time job, we pass grain through two separators using the Cascade method. Separators can work both sequentially and in parallel,” the manager explains.
How to dry at the Volnogorsk elevator
On the “Volnogorsky elevator” there are two grain dryers — chipboard-50 and chipboard-32. For peas, chipboard-50 is more often used there. it is unified on the elevator-the grain dryer can be dried in flow mode or in recirculation mode.
“We have installed an operational bunker near DSP-50. In this hopper, we form grain batches based on humidity. This gives us the opportunity to combine-add some dry grain to the wet one, thereby increasing the productivity of the dryer,” says Alexander Krat.
He explained that in one pass in chipboard-50, up to 6% of the humidity on peas is removed. From the dried batch, some legumes are released and moved to the warehouse, and some are left. Dry beans are mixed with wet ones, moisture is redistributed, wet peas are dried, while energy resources are saved and the drying process is accelerated. The cap that regulates the discharge frequency is set to 40 seconds.
“We do not need to immediately pour a drying agent over wet grain, wait for the separation of moisture, steam, and so on, everything happens by itself, thanks to mixing. The drying speed itself increases. In addition, if we talk about peas, this makes it possible to dry them in a more gentle mode. For peas, the maximum heating of beans is allowed – 40-45 °C, and the maximum temperature of the heat agent is 70-80 °C,” says the elevator director.
He emphasizes that when drying peas, it is very important to control the temperature conditions, otherwise the beans will split.
“When working with all legumes – when drying, cleaning, laying in the composition, it is advisable to choose the shortest routes, because every bucket of Noria that hits the grain, every box in the dryer through which the same legumes pass, unfortunately, lead to injury. This is such a “fragile” crop, which is very, very badly injured, and instead of commercial peas, you can get waste,” Alexander Krat emphasizes.
To prevent legumes from fighting, the Volnogorsk elevator optimized its routes as much as possible. The warehouses where peas are moved are located next to the dryers. There are also points of shipment to road transport and railway, respectively, the chain of grain movement is as short as possible.
The company tries to put peas in warehouses after drying and no longer move them, so as not to injure the beans.