Evaluation of Linseed Straw as a Fiber Resource from Kazakh Agriculture

ABSTRACT

Kazakhstan has become a leading grower and exporter of linseed; however, domestic enterprises are unable to ensure a complete cycle of processing of these crops. Especially pressing is the need for rational use of the stem biomass, which is simply wasted or burnt, causing irreparable damage to the ecosystems of the regions where it grows. The main problem of fiber in Kazakhstan is the lack of appropriate technology for bast fiber processing and the lack of specialists in this field. In search of ways to extract and spin linseed fibers, the authors of this article made an attempt to use worsted machines designed for wool for these purposes. The fibers obtained have satisfactory values for the following spinning process.

摘要

哈萨克斯坦已成为亚麻籽的主要种植国和出口国;然而，国内企业无法确保这些作物的完整加工周期. 特别紧迫的是需要合理利用茎生物量，因为茎生物量只是被浪费或燃烧，对其生长地区的生态系统造成了无法弥补的损害. 哈萨克斯坦纤维的主要问题是缺乏合适的韧皮纤维加工技术，也缺乏该领域的专家. 为了寻找提取和纺亚麻籽纤维的方法，本文作者尝试使用专为羊毛设计的精纺机器来实现这些目的. 所获得的纤维对于下面的纺丝过程具有令人满意的值.

KEYWORDS:

• Linseed straw
• harvesting
• decortication
• processing
• shives
• linseed fiber
• machines
• chemical composition of fibers
• fiber morphology

关键词:

• 亚麻籽吸管
• 收割
• 去角质
• 处理
• 护罩
• 亚麻籽纤维
• 机器
• 纤维的化学成分
• 纤维形态

Introduction

In recent years, Kazakhstan has taken first place in linseed flax production, overtaking Canada, Russia and China (Profile 2022; Zhengjun et al. 2020). Every year more land is made available for its cultivation, which is explained by appropriate growing conditions and the high demand not only in domestic but also in foreign markets.

Kazakhstan has different climatic zones, from steppe and forest-steppe in the north to deserts and semi-deserts in the south. Linseed flax is grown in Kazakhstan mainly (95%) in the northern regions – North Kazakhstan, Kostanay and Akmola Regions (Figure 1). In the southern part of Kazakhstan, linseed flax cultivation started in the foothill areas with a less arid climate.

Figure 1. Main linseed flax growing regions in Kazakhstan.

Linseed (Linum usitatissimum L.) is a suitable plant for arid and moderately arid steppe conditions. It easily overcomes the lack of moisture in the initial period of its development and survives drought before flowering thanks to the use of productive moisture reserves from deep soil horizons. In the early June drought and the absence of productive moisture in the available soil layer, flax retards its development by delaying the growing season. This contributes to further good absorption of late-summer precipitation in July and August. In general, linseed flax is not very demanding in terms of soil fertility and can be grown on any soil except heavy marshy soils, which easily form a thick crust, and saline soils. Late rainfall shows linseed’s ability to assimilate this rainfall productively, while for grain crops late rainfall is not as productive as it is delayed and falls in the heading-filing phase. Moreover, these rainfalls reduce the marketability and quality of the grain, while the quality of linseeds is only slightly affected. In general, linseed flax is one of the most profitable linseeds due to its lower costs. Flax consumes between 320 and 400 units of water per unit of dry matter during the vegetation period, depending on variety and conditions, which is 10% less than spring wheat. Flax is a good forecrop for cereals, which is advantageous for a large number of agricultural enterprises that grow cereals as well as linseed. One of the special features of flax cultivation in Kazakhstan is the active support of the state for the cultivation of linseed crops (sunflower, flaxseed, soybean) (Akhmetov 2016). Such diversification contributes to soil fertility, reduces the impact of yield and price fluctuations and promotes the development of new value chains.

Flax (linseed flax) cultivation has increased significantly over the last 7 years (2014–2021) from 556.2 thousand ha to 1342.5 thousand ha (Figure 2) (Karabanov 2021).

Figure 2. Sown area and linseed flax production in Kazakhstan in the last 7 years, thousand hectares.

Linseed flax is grown in Kazakhstan mainly for the production of seeds and linseed oil, which are exported to China, EU countries, Russia, and Afghanistan, where further processing of linseed includes isolation of plant proteins, lignans, dietary fibers and products of deep processing.

Currently, nutrition scientists and industry are evaluating new trends of partial replacement of animal proteins with plant proteins, which not only improves the health benefits of meat products, but also meets the need of many scientists, activists, and public authorities to reduce meat production for ethical reasons and to protect the environment. The presence of bioactive proteins and peptides with antioxidant, antihypertensive or neuroprotective properties, as well as a relatively balanced profile of exogenous amino acids with sulfur-containing amino acids makes the proteins of oil crops (flax, hemp, chia, coconut, evening primrose, milk thistle, nigella, pumpkin, rapeseed, sesame, and sunflower) a valuable functional component or alternative protein source, especially for the baking and meat industries. Linseeds are also favored by their low allergenic capacity (Kotecka-Majchrzak et al. 2020).

However, a pressing problem that needs to be addressed as soon as possible is the processing of linseed stalk biomass. As the area under flax cultivation expands, problems with straw handling are also increasing. It does not decompose well in the season winter and makes sowing in the following season much more difficult. Some farms mow the stalks at harvest, press the stalks into bales and then burn them; others leave the stalks in the fields and burn them in spring. In the process, an enormous potential of fiber raw materials is destroyed.

Since the Neolithic, flax has been used not only as a oil crop but also as a fiber crop. Traditionally flax fibers were widely used in weaving and spinning for many centuries until in the 18^thcentury they were systematically replaced by cotton. Flax fiber, which is three times stronger than cotton fiber, was used for the production of flax linen because of its natural softness, ability to flatten, wear resistance, absorbency, and strong swelling properties (Salmon-Minotte and Franck 2005). It is worth noting that long-stalked flax and crown flax were used for textile purposes.

At present, the stalks of linseed are mainly used as fuel and soil fertilizer due to the short length of the stalks, less than 0.35 m (Dudarev 2020). The use of linseed straw as an additional by-product has been the subject of many different scientific studies in recent decades.

Indian researchers (Shaikh et al. 1992) suggested methods for disposal of the stalk biomass, i.e., extraction of fibers with further production of single or triple yarn, production of good quality wood pulp followed by the production of paper of different qualities.

The raw material from flax can also be used in biopolymers, aerospace and automotive industries, as well as insulation, building materials, fine agrochemicals, pharmaceuticals, cosmetics and food. Other applications for short coarse fibers include cellulose, cigarette paper, packaging, laminates, coatings, flake boards and nonwovens. The range of applications for nonwovens is very broad: from furniture to geotextiles and chemotextiles (Kozłowski, Mackiewicz-Talarczyk, and Barriga-Bedoya 2010).

Ukrainian scientists (Dudarev and Say 2018) have proposed a method for harvesting linseed in a resource-saving way, which allows the stalks to be preserved without damage. It has been shown that the proposed technology enables the extraction of fibers suitable for the production of nonwovens, technical textiles, and paper.

Scientific studies conducted in field trials in Germany and Switzerland have shown that an average of 5 t of straw can be harvested from one hectare in addition to the seed yield (Rennebaum et al., 2002) (Mediavilla, Mediavilla et al. 1999)., Studies under more comparable natural conditions in continental climates have also shown a potential straw yield of up to 5 t/ha of flax straw in Canada (Silska and Bocianowski 2018). Several studies have shown that a fiber content of up to 25% can be expected when processing flaxseed straw (Barton et al. 2002; Diederichsen and Ulrich 2009).

The stalks (straw) of linseed contain 20 to 24% fiber material. The stalk is cylindrical, naked, covered with a waxy coating, and changes color during growth: light green -> milky-waxy -> light yellow -> yellow. Depending on the stalk thickness, flax is divided into thin-stalked − 0.8–1.2 mm in diameter, medium-stalked − 1.3–1.5 mm and thick-stalked − 1.6 mm and more (Dalabayev, Sakenova, and Shaimerdenov 2019).

According to the statistics (Karabanov 2021) on the average straw yield of 2 t/ha, 1058.4 thousand tonnes of linseed straw were produced on a cultivated area of 1,342.5 thousand ha in 2021. At the same time, 221.68 thousand tonnes of fiber (at an average yield of 20%) were lost in Kazakhstan in 2021 and burnt in the fields, which caused great damage to the environment due to the lack of a comprehensive technology for processing linseed flax stalk biomass at domestic enterprises.

As mentioned above, a major problem is the lack of appropriate facilities for processing unused stalk biomass. Linseed fiber has not yet been processed or spun in Kazakhstan.

In the search for possibilities to spin linseed fibers, the authors attempted to use worsted spinning machines developed for wool for this purpose. At the same time, it was necessary to study the physical and mechanical properties of the fibers obtained and compare them with samples from Belarus and Belgium.

Thus, it is possible to draw a conclusion on the necessity of developing methods for processing linseed flax stalk biomass in Kazakhstan. The solutions found will contribute to the transition of the national economy to the sustainable development of production, and new opportunities for growth will open up at the expense of previously unused agricultural biomass.

Materials and methods

Three types of raw material samples from different regions of oilseed flax cultivation – Kostanay (I), Akmola (II) and Almaty Region (III) – were selected as research materials (Table 1).

Table 1. Raw materials samples and their characteristics.

Raw material types	Raw material production region	Raw material characteristics	Harvesting methods
I	Kostanay Region	Fibers processed at the scutching-and-breaking machine under Troyana LLP production conditions	Harvesting with combines where the seeds are combed off and stalks are cut above ground
II	Akmola Region	Stalks with a high number of pedicels
III	Almaty Region	Stalks with few pedicels	Two stages: top of stalks are mowed or stripped for seed threshing, then the remaining part of stalks is mowed for straw handling

The following laboratory equipment was used to process raw materials II and III:

1. A device for shedding and parallelization of bast fibers (laboratory breaking machine) to extract fiber from the stalks.

A schematic diagram of the Device for Shedding and Parallelization of Bast Fibers (laboratory breaking machine) is shown in Figure 3. The stalks (1) are fed through a funnel (3) between toothed roller pairs (4). The rollers rotate and simultaneously make a reciprocating movement along the axis of rotation. This increases the intensity of the pulling and thus, improves the cleaning of fibers from shives (Assanova et al. 2019). The given machine has been specially developed for the processing of bast fibers (Otynshiyev and Assanova 2020).

Figure 3. Process scheme of device for shedding and parallelization of bast fibers (laboratory breaking machine).

2–3. Hammering machine and scutching machine for the cleaning of fiber from shives. Parameters of the hammering machine:

Diameter of the cylinder on spikes− 600 mm

Cylinder speed− 400 rpm

Number of spikes− 144 pcs.

For scutching, a TPSh-1 scutching machine was used, designed for processing coarse wool. The process scheme of the machine is shown in Figure 4.

Figure 4. Process scheme of TPSh-1 scutching machine.

Operation parameters of the TPSh-1 scutching machine:

Main cylinder diameter− 1000 mm

Main cylinder speed− 150 rpm

Speed of work rollers− 20 rpm

Performance capacity− 100 kg/h

The working principle of the TPSh-1 scutching machine is to be described as follows: The fiber is put on the feeding (table 4), which slowly conveys it through the feeder pair to the main cylinder (3). The main cylinder has 32 rows of metal spikes with a height of 100 mm. These spikes pick up the fiber from the working pair and intensive fiber scutching takes place in the area of interaction of the main cylinder and work rollers (2). Then the fiber is sucked to the perforated cylinder of the condenser (1), and from this cylinder, the fiber is knocked down by another roller with rubber bumpers.

4. Single-cylinder roller carding machine (Figure 5) designed for wool processing.

Figure 5. Process scheme of the carding machine.

1-breast, 2 – swift, 3 – doffer, 4 – workers, 5 –strippers, 6 - fancy

Operating parameters of the single-cylinder roller carding machine:

Diameter of feed rollers− 80 mm

Diameter of the taking-in roller− 400 mm

Diameter of the breast roller− 600 mm

Diameter of the stripper− 400 mm

Diameter of the swift− 1200 mm

Diameter of the doffer− 800 mm

Diameter of the workers− 230 mm

Diameter of strippers− 120 mm

Number of card clothing of the swift− 14

Number of card clothing of workers− 18

Number of card clothing of doffer− 20

Clothing of breastmetallic clothing

Feed speed− 0.12 m/min

Breast roller speed− 170 m/min

Swift speed− 390 m/min

Speed of breast workers− 8 m/min

Speed of main carding workers− 10 m/min

Doffer speed− 16 m/min

Raw materials, intermediates and finished samples have been analyzed for selected physical and mechanical properties by laboratory methods in order to assess the different processes exposed to the materials:

1. Flax fiber fineness determination: microscopy.GOST 10213.0 : 2002 Staple chemical fibre and tow - Rules of acceptance and method of sampling Publishing House of Standards, Moscow, 2003

2. Determination of mass fraction of shives and fiber: GOST R 53484:2009 Scutched Flax Fiber. Specifications (2010).

3. Determination of linear density of flax fiber and coefficient of variation of linear density: GOST 10213.1-2002 Staple Chemical Fiber and Tow. Linear Density Test Methods.

4. Determination of the mass fraction of lignin in flax fibers: sulfuric acid method or hydrolytic weight method for determination of lignin.

5. Retting method. Retting was carried out in warm water as well as in a slightly alkaline solution of sodium bicarbonate (NaHCO₃). The water temperature during warm-water retting was artificially kept in specially equipped thermostats between 33-38°C. This temperature created favorable conditions for the microorganisms and thus significantly reduced the duration of pectin decomposition.

6. Pedicel determination method. The high pedicel number causes great difficulties in the production of fibers and yarns. Since so far there are no methods for determination of pedicels, we used the method for determination of shives and fibers and applied it to pedicels. 100 g of each of the samples were taken. The pedicels were separated manually and their number per 100 g was also counted manually, based on this, the number of pedicels per 1 g was calculated.

7. Yarn spinning process. The processes of making yarn according to the worsted wool spinning system were carried out in 2 main stages: first, slivers were made from fiber, and then yarn was made from it. In this experiment, flax fiber was first processed on an AРТ-120ш opening and scutching machine (see Figure 6) for cleaning from shives and mineral impurities and for loosening.

   Figure 6. General scheme of processing linseed flax stalks.

   

Spinning was carried out using the following process flow:

1. Scutching on the ART-140Sh opening-and lap-forming machine.

2. Carding on Tematex carding machine

3. Drawing on SANT’ ANDREA NOVARA intersecting machine, model SEU-CA − 3 transitions.

4. Combing on Textima combing machine, model 1603

5. Drawing on Cognetex intersecting machine, model SC400 - 3 transitions.

6. Roving on a Cognetex roving machine

7. Spinning on Cognetex FL-7 spinning machine

8. Winding of the yarn onto cone on the winding machine.

Experimental and results

The general scheme of processing linseed flax stalks is as follows:

The stalk material delivered from Akmola (II) and Almaty (III) Regions was processed on a Device for Shedding and Parallelization of Bast Fibers (laboratory breaking machine) in the laboratory of the Almaty Technological University (Figure 3).

Subsequently, the obtained technical fibers were processed first on a hammering machine and then on a TPSh-1 scutching machine to remove shive residues.

To test the suitability of the worsted equipment for spinning linseed fibers, a carding machine designed for wool processing was used. For this purpose, the working equipment, in particular the card clothing number of the main cylinder used for fine wool, was changed from 28–30 to 14.

A summary of the results of the study of raw materials from Akmola and Kostanay Regions is shown in Table 2.

Table 2. Indicators of the samples from Akmola and kostanay regions.

	Indicators	Fiber samples from Akmola Region (II)	Fiber samples from Kostanay Region (I)
Raw materials	Linear fiber density, (tex)	89	26.2
	Average fiber length, L (mm)	101.5	232
	Ultimate fiber diameter, D, micron	15.1	14.3
	Mass fraction of shives (%)	71.3	62
	Of these, shives with fiber (%)	34.7	32
	Fiber mass fraction (%)	28.7	38
Hammering machine	Linear fiber density, (tex)	61.3
	Average fiber length, L (mm)	81
	Mass fraction of shives (%)	53.3
	Of these, shives with fiber (%)	29.6
	Fiber mass fraction (%)	46
Scutching machine	Linear fiber density, (tex)	47.8
	Average fiber length, L (mm)	70
	Mass fraction of shives (%)	45.5
	Of these, shives with fiber (%)	23.1
	Fiber mass fraction (%)	53.8
Breaking-shaking line	Linear fiber density, (tex)	-	18
	Average fiber length, L (mm)	-	160
	Mass fraction of shives (%)	-	56 (of which 32% are pedicels)
	Of these, shives with fiber (%)	-	32
Carding machine	Linear fiber density, (tex)	25.8	9.75
	Average fiber length, L(mm)	56	108
	Mass fraction of shives (%)	11.3	46 (of which 20% are pedicels)
	Fiber mass fraction (%)	88.3	54

As can be seen from the data in Table 2, the linear fiber density of the regions presented differs greatly due to the processing of the Kostanay raw material on the breaking-and shaking line at the supplier’s plant.

With each further processing, the linear fiber density decreases, so that after the processing on the hammering machine it has decreased by about 30%, on the scutching machine by another 25%, and on the carding machine by 45%. The greatest reduction in fiber density takes place on the carding machine. Fiber density I was reduced by 22% on the breaking and scutching machine and almost halved on the carding machine. Mechanical textile processing thus gradually loosens the fiber bonds and reduces the number of ultimate fibers in the textile fiber.

The average length of the fibers in the samples from Akmola Region decreased from 101.5 mm to 56 mm during processing. This length is sufficient for processing flax fibers on wool worsted equipment. The length of fibers in the raw materials of the sample I was 232 mm, after the breaking and shaking machine, it was 160 mm, and after carding − 108 mm.

During processing, the percentage of shives in the samples decreased from 71% to 11.3% in the Akmola samples. In sample I, the decrease in shives was only 25.8%. This is explained by the fact that in this sample the pedicel, which is not removed with the standard equipment, makes up the major part.

The lignin content in the linseed raw material was 14.7%, and in the sliver after carding 2.2%. The lignin crumbles during processing in the processing equipment.

Research of the influence of retting on the degree of linseed flax straw deflaking

As the fibers produced were stiff, further research was carried out to find better processing and longer textile fibers using a retting process. Retting is a biological or chemical treatment carried out to facilitate the separation of fiber bundles from the woody part of the stalk as well enabling the separation of fiber bundles in finer structures (Kozlowski).

Table 3 shows the average measurement results of the main fiber parameters determined after the warm-water retting technique. The duration of the warm-water retting ranged from 24 to 120 hours. The average fiber diameter was 16.8 ± 2.7 µm.

Table 3. Comparative values for linear density and fiber length as a function of warm-water retting regimes.

Retting time, h	Retting in water				Retting in a slightly alkaline medium
	Linear fiber density, (tex)	Average fiber length, Lav (mm)	Mean square deviation S y	Coefficient of variation C v (%)	Linear fiber density, (tex)	Average fiber length, Lav (mm)	Mean square deviation Sy	Coefficient of variation Cv (%)
24	6.7	252	116	46	8.9	221	86	39
48	4.7	230	96	42	6.7	253	107	43
72	6.3	234	88	38	5	274	99	36
96	5.4	232	100	43	4.2	271	83	31
120	5.9	237	90	38	5.9	196	64	33

During processing, the linear fiber density changes most significantly. With increasing retting time, the linear fiber density decreased to 3.1 in both cases. The results of retting in plain water and slightly alkaline media show almost identical results. During the textile treatment, the average fiber length is shortened. It decreased by about 10–15% in both retting regimes. No definite regularity was found between retting duration and average fiber length. As the laboratory tests of warm-water retting of flax stalks and the processing of the flax fiber obtained have shown, the latter have physical and mechanical properties that allow them to be processed on worsted wool equipment.

After retting, the fibers were separated from the shives and then manually carded and processed on carding and draw frame machines.

The influence of the number of transitions during processing on the draw frame on the linear density of fibers

The possibility of splitting the resulting technical fibers down to their ultimate fibers was investigated. It should be noted that the combs of the draw frame strongly break the fibers as they are drawn (GOST 10213.1-2002 Staple chemical fibre and tow. Linear Density Test Methods. Standartinform. 2003). Thus, if the average linear density of the fibers after mechanical treatment on a decortication machine was 12.1 tex, it dropped to 3.5 tex after 10 transitions on a draw frame. Such a decrease in linear density occurs after 5–6 transitions and is not observed thereafter. The results are shown in Table 4.

Table 4. Change in linear density depending on the number of draw frame transitions.

Linear fiber density after decortication, (tex)	Drawing transitions
	1	2	3	4	5	6	7	8	9	10	11	12	13	14
12.1	8.5	6.7	6.5	6.3	5.4	5.0	4.5	4.4	4.3	3.6	4.0	3.5	3.5	3.6

A study of the feasibility of pedicel removal in relation to harvesting methods

A major problem that complicates the production of linen yarn from linseed flax fibers is the high pedicel content. As mentioned earlier (Table 1), when the stalks are harvested with combines, the pedicels on which the seed capsule is attached, remain on the stalk. This pedicel can hardly be removed both during the initial processing of the stalks in the breaking-and-shaking line and in the following processes of preparing the fibers for carding. The high pedicel number causes great difficulties in the production of fibers and yarns. Several machines were tested for removing the pedicels. The tests were carried out with raw materials from Kostanay (I) and Almaty (III) regions and the results of the tests are presented in Table 5. It should be noted that when using the two-step harvesting method used in the south of Kazakhstan, the straw length is shorter, but only a small number of pedicels remain.

Table 5. Shives and pedicels content per 100 g of fiber by process transition.

Transition description	Raw Materials I		Raw materials III
	Mass fraction of shives, (%)	Number of pedicels, (units/gram)	Mass fraction of shives, (%)	Number of pedicels, (units/gram)
Raw materials	62.0%		-	-
Breaking and scutching line (3 shakers + 2 breakers)	49.7%	115	-	-
Laboratory breaking machine	-	-	2.5%	5.7
Hammering machine	-	-	1.9%	2.1
TPSh scutching machine	-	-	1.5%	1.1
ART-120Sh opening and lap-forming machine	39.7%	-	-	-
TEMATEX wool carding machine (Italy) with three Morel system devices	6.82%	55	-	-
TEMATEX combing machine, model 1603	1.08%	6	-	-

Research shows that it is practically impossible to remove the pedicels completely with the preparation equipment intended for wool processing. The pedicels are very firmly attached to the flax fibers. Even on the Morel carding system, only half of the pedicels are removed. After carding, the sliver contains about 55 pedicels per 1 g of fiber, which is quite a high amount for the production of yarn. The pedicels can be removed from the fibers by processing the flax sliver on a combing machine. In this case, 6 pedicels per 1 g remain.

When processing raw materials (III) of Almaty Region to prepare fibers for spinning, the breaking and scutching equipment are sufficient to remove the shives and pedicels from the fibers.

To estimate the possibility of processing the obtained short fibers of Kazakh linseed flax, their physical and mechanical parameters were compared with long fiber from Belarus and Belgium (Table 6).

Table 6. Comparison of the physical-mechanical indices of tops obtained from linseed flax with the tops from Belarus and Belgium.

No.	Sample description	Average fiber length, (mm)	Coefficient of variation in length, (%)	Linear density, (tex)
1	Samples obtained from the Orsha Flax Mill, Belarus	-	-	-
1.1	Long fiber before carding	-	-	8.55
1.2	Long fiber after carding	-	-	5.30
1.3	Long fiber after the draw frame	307	-	6.13
1.4	Carding tow	174	43	4.50
1.5	Sliver after combing	140	43	3.69
2	Combed sliver made in Belgium	181	41	3.42
3	Kazakhstan fiber (samples of Kostanay region)	108	-	4.75

As can be seen from the table, the Kazakh flax fibers are somewhat coarser and shorter than the Belarusian and Belgian fibers.

A study on the feasibility of yarn production on wool worsted spinning equipment

Considering the most suitable fibers of Kostanay region, the authors of this study decided to process them into yarn under the production conditions of Kassiyet JSC enterprise (Kyrgyzstan) on wool worsted equipment. The corresponding spinning plan is presented in Table 7.

The physical and mechanical parameters of the yarn obtained are given in Table 8.

Table 7. Spinning plan.

Transition description	Weight of incoming sliver, g/m	The number of folding	Drawing	Weight of outcoming sliver, g/m	Speed
Carding machine				29	30 m/min
Intersecting	29	4	5.3	24	140
Intersecting	24	6	6	24	140
Intersecting	24	4	6	16	140
Combing machine	16	16		16	120 rpm
Intersecting	16	8	8
Intersecting	24	6
Intersecting	20	4
Roving frame				1,0×2
Spinning frame	1х2	1	16	Nm 10	5300 rpm

Table 8. Physical and mechanical parameters of Kazakhstan yarn.

Indicators	Units of Measurement	Values
Actual metric number	NM	10.0
Yarn twine	Twisting/m	450
Relative breaking load	cH/tex (gram/tex)	18.8
Nominal linear density of fibers in the yarn	tex	2.9

The spinning breakage rate was 300 breaks per 1,000 spindle hours, which is considered satisfactory for spinning this type of fiber.

Conclusion

1. The Kazakh linseed straw (stalk) of can be used for the production of various textile materials, including nonwovens for technical purposes, yarns, and fabrics for both technical and household purposes.

2. The main problem in textile processing of flax material is a large number of pedicels in the technical fiber when using modern high-speed combine harvesters for harvesting linseed flax, which detach the seeds from the stalks. In this case, the pedicels remain on the stalk and can hardly be removed during primary processing.

3. Combing is the key to removing the pedicels and helps to remove them almost completely.

4. The physical and mechanical properties of fiber of Kazakh linseed flax are similar to the parameters of the short fibers and when combed during the processing of long flax fiber.

5. For processing, the fiber obtained from linseed stalks the worsted equipment designed for wool can be used. However, the equipment needs to be partially upgraded, as the cover on the cylinder head needs to be replaced.

6. The indicators of properties of the yarn obtained meet the requirements of the standards for yarns for technical textiles and upholstery fabrics, which allows a conclusion to be drawn about the visible prospects of previously unused raw materials and potential economic growth in the manufacturing sector of the Republic of Kazakhstan.

Highlights

Kazakhstan has become a leading producer and exporter of oil flax. However, domestic enterprises are not able to provide a full cycle of processing these crops. Particularly acute is the need for the rational use of stem biomass, which is simply thrown away or burned in the fields, causing irreparable damage to the ecosystems of the growing regions.

The main fiber problem in Kazakhstan is the lack of appropriate bast fiber processing technology and the lack of specialists in this field. According to statistics, with an average straw yield of 2 t/ha in 2021, on a sown area of 1342.5 thousand hectares, 1058.4 thousand fibers were produced (with an average yield of 20%) were lost in Kazakhstan in 2021 and burned in the fields, which caused great damage to the environment due to the lack of an integrated technology for processing the biomass of flax stalks at domestic enterprises. In search of methods for obtaining and spinning flax fiber, the authors of this article attempted to use worsted machines designed for wool for these purposes.

The obtained fibers were compared by the authors with fibers from Belgium and Belarus, and found that domestic fibers have satisfactory characteristics for the subsequent spinning process. In Kazakhstan, flax has not yet been processed or spun.

We recommend using the resulting yarn for technical textiles and upholstery fabrics, which allows a conclusion to be drawn about the visible prospects of previously unused raw materials and potential economic growth in the manufacturing sector of the Republic of Kazakhstan.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Personal funds of the author Albina Assanova