Põlevkivi avakaevandamise alternatiivsete transpordi- ja rikastamisvõimaluste analüüs Narva karjääri tingimustes [Magistritöö. Juhendaja: T. Tomberg]

Töös käsitletud alternatiivsete transpordi tehnoloogilise skeemi analüüsi tulemused näitavad, et praeguse tehnoloogia kasutamine on väga kulukas. Praeguse tehnoloogia suurimad miinused on kõrged kulud kütusele ja personalile ning kallurite madal tootlikkus. Kõige kaugemast tranšeest õlitehase lattu on praegu võimalik tunnis välja vedada vaid 47 tonni kaevist ning kui eerind jõuab mäeeraldise lõppu, väheneb see 40 tonnini tunnis. See tähendab, et ete edasinihkumisega kaasnevad ressursi erikulud kaevise veole. Positiivsena võib välja tuua madala esmase investeeringu ning sissetöötatud transpordisüsteemi.

Karjääritranspordi konveieriseerimine on aeganõudev, kuid majanduslikult põhjendatud protsess. Konveieri kasutamine ühtlustaks toodangut. Konveieriseerimisega väheneb vajadus tööjõu järele ja säästaks personalikulusid. Konveieri tootlikkus oleneb kopplaaduri ja purustuskopa tootlikkustest Praegust tehnoloogiat kasutades oleks ühe tranšee kõrge kütteväärtusega kihtide puhul konveieri tootlikkus 187 t/h. Purustuskopa kasutamisega tehnoloogilise variandi korral oleks see 164 t/h. Purustuskopa ja kalluri kasutamisega tehnoloogilise variandi korral jääks kalluri tootlikkus samaks.

Võrreldes kolme tehnoloogilise variandi kulusid on selge eelis purustuskopa ja konveieri variandil. Ettevõtte kulud on sellise tehnoloogia puhul 350,95 milj. euro võrra väiksemad kui praeguse tehnoloogia kulud. Kolme variandi viieteist aasta kulud oleksid järgmised: praegust tehnoloogiat kasutades 562,88 milj. eurot, variant I tehnoloogial 211,94 milj. eurot ja variant II tehnoloogial 583,70 milj. eurot. Kulude suur vahe tekib kütusehinna ja elektrihinna vahest. Variant II kasutades on ka suuremad personalikulud.

Investeeringuid arvestades on konveieri tehnoloogia kuus korda kallim. Konveierit kasutades on investeering 62,62 milj. eurot. Teiste tehnoloogiate puhul on investeeringud 11-12 milj.eurot.

Arvestades 15 aasta kulusid ja investeeringuid oleks otstarbekas kasutusele võtta konveieri ja purustuskopa tehnoloogia. Ettevõtte säästaks sellega 294,10 milj. eurot. Alternatiiv II kasutusele võtmine tekitaks võrreldes praeguse tehnoloogiaga ettevõttele lisakulutusi nii mäemasinate kulude kui ka investeeringute osas.

Abstract

The objective of this thesis is to determine the justification of alternative method of ore transport and enrichment. The drawbacks of the current technology are the high fuel consumption of the dumper trucks and the uneven quality of the oil shale that reaches the warehouses. In order to ensure the required calorific value for the power plant and the oil plant, different layers of the oil shale have to be mixed. An alternative method to the current technology would be implementing the use of a crusher bucket for the enrichment of the low calorific oil shale layers and developing a network of conveyors to ensure the even quality of the oil shale. Another alternative would be the continuation of the current transport technology and implementing the use of the crusher bucket to enrich the low calorific oil shale layers to ensure the required quality of the oil shale. To compare and to find out the optimal solution between the current and alternative technologies the author has used the comparative analysis method from the economic aspect.

The result of the analysis on alternative methods of ore transport indicates that the use of the current technology is very expensive. The biggest drawbacks of the current technology are high fuel expenses, high personnel costs and low productivity. The transportation of ore from the most distant trench to the oil factory warehouse is currently 47 tons of ore per hour. At the end of the opencast mine the productivity will decrease to 40 tons per hour. That means that each time the mining front moves forward the company must make more expenses on each ton of ore transported from the trench. The positive sides of current technology are low initial investment and well developed transport system.

The construction of the conveyor is a time-consuming process, but it would be beneficial. Using the conveyor technology would improve the quality of oil shale. The technology requires considerably smaller staff thus it would save personnel costs. The productivity of the conveyor depends on the productivity of the bucket loader and the crusher bucket. The productivity of the bucket loader per one tranche of high calorific layers is 187 tons per hour. Using the crusher bucket technology the productivity is lowered to 164 tonnes per hour. By using the crusher bucket and dump truck technology the productivity would remain the same.

Comparing the costs of the three technologies it is clear that the biggest advantage is on the side of the crusher bucket and conveyor technology. The company's expenses of such technology, would be 350,95 million euros smaller than the expenses of the current technology. The expenses of all technologies are as follows: current technology 562,88 million euros, alternative I technology 211,94 million euros and alternative II technology 583,70 million euros. The big difference between the expenses is due to big differences of fuel and electricity prices. Using the dumper truck technology would also result in higher personnel costs.

The initial investment of the conveyor technology is six times bigger compared to the other two technologies. The initial investment of the conveyor technology is 62,62 million euros. The initial investment of the other technologies is around 11 million euros.
Given the 15-years of expenses and the initial investment it would be wise to start implementing the conveyor and the crusher bucket technology. It would save the company 294,10 million euros in 15 years. The implement of the alternative II technology would create additional costs for the company as well as extra expenses due to costlier initial investment.