1. Abstract proposition.

Mining of thin and very thin coal seams with thickness 0.55 – 0.9 m with help of modern equipment is practically impossible without coal-cutting with stone. Such technology leads to mixing of coal with rock. For coal distribution to consumer is necessary to benefit mined rock. Proposed selective technology of coal extraction with backfill provides high quality of product practically with host rock ash content 15 – 18% and allows to leave rock in mine.


2. Proposition description.

In Ukraine commercial reserves of coal is enough for working of mining enterprises during 150 – 200 years at annual extraction near 100 million tonnes. Most part of these reserves (near 70%) is located in seams with thickness 0.55 – 0.9 m. This problem mainly presents on a Western Donbass mines where quantity of reserves in seams with thickness 0.55 – 0.9 m are equal to 51%, and on some mines far exceed this value and reaches 80%. Majority of active longwalls of Western Donbass mines develop seams with thickness less than 1m, that’s why almost all stoping faces extract coal with side rocks cutting. Nowadays value of cutting is from 5 – 10 cm to 30 – 40 cm. Such technology leads to mixing of extracted coal with rock to 40%.


3. Innovation aspects and proposition advantages.

Mining of thin seams with usage of selective technology has variety of advantages:

1. Usage of selective technology allows to essentially (from 44 to 15 – 18%) decrease ash content of extracted coal.

2. Backfill decreases rock pressure on mechanized support that creates more favourable conditions of its work.

3. By means of gate side gob pack construction deformation of neighbor to longwall mine working decreases in 1.5 – 2 times that creates conditions for its reuse.

4. By means of backfill decreases convergence of side rocks in longwall and essentially decreases inrush formation in work area.

5. Earth’s surface sinking during full backfill decreases more than two times.


4. Technical details.

Extraction of coal and rock during mining of low-thickness seams is realized separately, in two passes of shearer. At first pass of shearer detaches coal from massif, at second one – rock. Simultaneously with extraction realizes backfill in worked-out area with usage of pneumatic stowage equipment.

Backfilled rock is allocated in worked-out area of longwall nearby drifts as gob packs with width to 30 m. At short length of longwall and at great value of cutting can be materialized full backfill. Also backfill can be materialized from drivage works.


5. Technological keywords.

Selective technology, backfill, gob pack, thin coal seam, ash content.


6. Number of market appliance.


7. Current status of development.

- Implementation plan is present


8. Intellectual property rights.


9. Comments, dates, patent number.

Defended by patents of Ukraine # 62265, 35882, and 87663. Declarant and patent owner – NTU Dnipro University of Technology


10. Type of wanted collaboration.

Agreement with coal enterprise

Financial resources


11. Type of required partner.

Development team is looking for partners for such technology implementation in production.


12. Field activity of partner.

Mining and metallurgical enterprises


13. Tasks that facing to a partner.

Modernization of current equipment


14. Favored countries.

Ukraine, Poland, China etc.

Contact information

Organization: NTU Dnipro University of Technology

Address: Ukraine, 49005, Dnipro city, D. Yavornytskyi av., 19

Department: Chair of mining engineering and education

Phone: (0562)46-90-47, 47-14-72

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., This email address is being protected from spambots. You need JavaScript enabled to view it.