Индекс на документа:ПРИЛОЖЕНИЕ № 5
РИ-ИСУ08.02.00.00.00/5-1
“АСАРЕЛ – МЕДЕТ” АД – ГР. ПАНАГЮРИЩЕ
Technical assignment
Regarding: Grinding tests of bulk rougher flotation concentrate with newfine grindingequipment
1. Exisitng situation
Flotationflow-sheetofAssarelconcentratorincludesregrindball mill circuit ofbulkroughercopperconcentrateinordertoachievecycloneoverflow 80 % -0,080mm. Regrindcycloneoverflowfeedsthecopperselectiveflotationwherewe encounter somedifficultiesforraisingthecoppergradeofthefinalcopperconcentrate.
We have flotation tests, showing that finegrindingisrequired in the flotation process of Assarel concentrator for better liberation of fine-grained copper minerals. Grinding under 100 microns is consuminghigh energy, which is the reason that conventional drum ball mills are not effective for fine grinding at 80 % -0,04 mm.
In recent years modern and effective equipment for fine and ultrafine grinding has been developed. These new technologies use high-energy milling and have many advantages over the conventional ball mills.
2. Purposeofthestudy
Determinationoftechnicalandeconomicalcharacteristicsofgrindingprocessinnewverticalmillsforachievingaproductwithgrindsize 80 -0,04 mm.
3. Scope of the study
Subjectoftheresearchistheproductfeedingtheexistingregrindballmillcircuit, whichisabulkroughercopperconcentrate.
Forthispurpose, laboratorywet grindingtestswithcontinuousfeedarerequiredtoscale-upproduction-size continuous mill. The bulk rougher copper concentrate subject to this study has the following characteristics:
Grind size: approx.80 %- 0.080÷0.095mm
Specific gravity: 3÷3,5g/cm3
Feed slurry in the plant: 250 tph
Percent solids: 38÷45 %
“Assarel-Medet” will provide chemical analyses of the bulk rougher concentrate test sample by Cu, Fe, S, Al203, SiO2.
Thetest studywillbe performed in a laboratory of the company presenting the proposal.
Test-work shall be finalizedwith atestreportandperformancecurveofspecificgrindingenergyplottedagainst80 %.
Asaparttothetestreportaproposalforproduction-sizeequipmentmustbeenclosed. Theindustrialsizeequipmentforgrindingthebulkrougherconcentrateat 80 % -0,04 mmmust comprise the following parameters:
- specificgrindingenergyofthe mill(kW-hr/t)
- total required power (kW)
- number units for fine grinding of the proposed model
- standardmotorpower(kW)
- height of the mill (mm) without the motor
- totalheightofthemill(mm)including the motor
- total weight of the mill (kg)
-typeofthelining
- sizeandtype of the grinding media (mm и steel or other type of material)
- standardgrindingmediachargeof the mill (kg)
4. Requirementstothetestproposal
4.1Proposal details
- Proposalforatotalpriceofthetest-work
- Time for fulfillment of the test-work in working days
- First date for beginning of test-work
- Paymentterms(down payment, etc.)
- Referencesfortechnicalexperience
- Validityoftheproposal- at least 90 days
- Recommendationsfromthreepreviousclientsandclientsreferencelist with contact information
4.2Non-competitive part
- Court registration data
- Address, contactnames, phones, fax, email.
- Certificateof Good Standing.
5. Criteriaforacknowledgementofthetest-work
Expert Technical and Economical Council in ‘Assarel-Medet’ will discuss and accept the test-work report.
6. Otherconditions
Proposal must be submitted until 30.04.2013 in a sealed envelope by mail or fax ++359 357 60250 or email: ,for the attention of theExecutive Director with following title: Proposal for: „Grinding tests of bulk rougher flotation concentrate with new fine grinding equipment”.
Proposals will be open and reviewed by a committee.
You will be duly notified about the results of the committeedecision after reviewing of all submitted proposals.
The order for quotation storage, transparency and adherence to principles established in the company exclude possibilities for any influence over the contractor selection or over the quality of the ingoing control through corruption. Moreover, if such attempts are found, the respective officials will be disciplinary dismissed from work and the contracts with the respective partners shall be terminated.
Forcontact: ‘Assarel-Medet’ JSC,phone: ++359 357 60210/int.624/ - NikolayKolev