Presentation is loading. Please wait.

Presentation is loading. Please wait.

Standardisation of Auto Sampler cum Sample Preparation Unit at Nandan Washery Dr R Dasgupta and Dr Kalyan Sen, 1999.

Similar presentations


Presentation on theme: "Standardisation of Auto Sampler cum Sample Preparation Unit at Nandan Washery Dr R Dasgupta and Dr Kalyan Sen, 1999."— Presentation transcript:

1

2 Standardisation of Auto Sampler cum Sample Preparation Unit at Nandan Washery Dr R Dasgupta and Dr Kalyan Sen, 1999

3 Nandan Washery Designed & Commissioned by M/S Voest-Alpine of Austria, product Komag Jigs (Coarse & Fine Coals) Flotation Cleans to Bhilai Steel Plant for metallurgical use Sampler before the Storage cum Loading Bunker

4 Material flow diagram of Nandan washery

5 Purpose uNo arrangement for sample collection during actual loading of washed coal uQuantity of samples from sampler is not adequate Y Less load on clean coal belt

6 Objective kTo standardise the Auto Sampler cum Sample Preparation Unit kUltimate Aim u Joint sampling by producer & consumer without any external surveillance kTo evolve & Articulate practical procedure for future use, within the broad guidelines of Stipulated Standards

7 CFRI Strategy To evolve methodology through participation of Nandan, CCSO & CFRI officers Stepwise study or approach Z Preliminary planning - at washery site Z Preliminary test experiments Z Final corrective measures, data collection, collation & Statistical tests

8 Preliminary Tests Conclusion w Adjustment of double roll crusher w Change in sampler time interval w Dividing ratio (?) w Replacement of Chemical balance w Procurement of Digital balance (20 kg) for Total moisture determination

9 Test Methodology v Sample Collection and Preparation Z Sampling Points identification Z Sample collection & preparation < Ash < Total moisture

10 Sampling Points Belt SampleS 1 (Stop belt) Flap SampleS 2 * Auto SamplerS 3 Bottle SampleS 4 * discontinued at later stage

11 Sampler cum Sample Preparation S1S1 S3S3 S4S4 S 2 - Flap

12 Ash Sample Preparation P Gross Sample P Air dry & Crush to 12.5 mm P Air dry (if required oven dry at 35 deg but not more than 2 h at a time) P Reduce the sample to 2 kg P Divide into 4 parts P 2 parts (Reserve); 1 part (212 micron) & 1 part (212 micron) P 1 part preserve as check sample P 1 part divide using laboratory divider (2 samples) P Sample A 1 Sample A 2

13 Total Moisture Sample Preparation Gross Sample Air dryRecord wt. Crush to 12.5mm Reduce 2.5kg Crush to 2.8mm Divide into 4 parts Sample A Sample B RESERVE Size 12.5 mm above ? Record Initial wt. Stage 1 loss% Stage 2 loss% Oven dry 35deg not exceed 2h Record wt. Stage 3 Moist. 10g, 108deg, 2h Y N

14 Statistical Analysis H Coal is heterogeneous material H Very difficult to achieve highest level of Sampling precision H In terms of variance D 80 % is from Sampling D 20 % is from preparation & analysis H Overall precision is influenced primarily due to Sampling H Utmost importance thus need to be given for Sampling

15 Statistical Analysis Testing of Bias v Paired samples v One member is the “System” under test v Other one “Reference” Z An intrinsically unbiased sample Z To be obtained by stopping belt method v Series of differences are subjected to Statistical analysis

16 Statistical Analysis Assumptions a A normal distribution of the variable a Independence of the errors of measurement a Statistical homogeneity of the data

17 Statistical Analysis C Test for flagging outliers C Estimation of number of pairs required C Assessment of Bias C Method I C Method II C Test for significant difference from zero C Test for significant difference from B (MTB) Basic Steps

18 Common Sample Preparation Common Bottle Sample Air dry Record wt. Crush to 2.8mm Divide into 2 parts Sample A Sample B RESERVE Record Initial wt. Stage 1 loss% Stage 2 loss% Oven dry 35deg not exceed 2h Record wt. Stage 3 Moist. 10g, 108deg, 2h Divide Crush to 2.8mm Sample C Ash Divide into 2 parts


Download ppt "Standardisation of Auto Sampler cum Sample Preparation Unit at Nandan Washery Dr R Dasgupta and Dr Kalyan Sen, 1999."

Similar presentations


Ads by Google