Mixing drum

Figure 38.4 illustrates a typical batch-type screw mixer. This unit consists of a mixing drum or cylinder, a single-or dual-screw mixer, and a power supply. 

S.I.L. uses standard concrete transit mixer trucks modified to provide gas or propane heat to the mix drum to prepare mixes for both precast and poured-in-place work. Since 1977 several poured-in-place field trials have been completed and numerous projects in the Calgary area have now been constructed. Precast products that have been marketed include parking curbs, pipeline weights, sewer pipe, median barriers, and sidewalk slabs. 

Into a porcelain dish, place 70 gram of potassium chlorate, 70 grams of freshly prepared wet mercury fulminate, 60 grams of antimony sulfide, and then 10 grams of styphnic acid. Then manual blend this mixture for several hours. A mixing drum may... 

The Panogen treater meters one treatment cup of pesticide per dump of seed into a revolving mixing drum. The pesticide flows into the drum from a tube and is distributed over the seed as the seeds rub against the walls of the drum. The correct dosage is achieved by selecting the appropriate size or treatment cup for the chosen seed dump weight. 

The powder obtained was dried again for 2 h at 60°C and homogenised for 24 h in a PTFE-lined mixing drum. The powder was then transferred into a dry-air glove box connected to a gas purification system. At this stage, the moisture content of the white clover was below 3% (w/w). Clean, brown-glass bottles provided with a PTFE ball for rehomogenisation were filled with ca. 25 g of material and closed with plastic inserts and screw-caps. 

The material was further processed at the Joint Research Centre of Ispra where further grinding (ball mill in zirconia) was carried out to pass a sieve with apertures of 125 pm. The material was then mixed for two weeks under dry air (which was replaced twice a day) in a special polythene-lined mixing drum. After this period, bottling was performed in batches of 40. One bottle was selected randomly out of each batch and set aside for the homogeneity study. 

When sufficient wet materials was collected, it was freeze-dried, ground in a zirconia ball mill and sieved to pass 125 pm apertures. The resulting powder was collected in a mixing drum and homogenised by continuous rotation under dry Ar over two weeks. Cleaned brown glass bottles were filled with approximately 5 g of material and closed with screw caps and plastic inserts. A PTFE-ball was added to facilitate later re-homogenisation in case segregation would occur. 

The milk powder from these 10 batches was homogenised in a mixing drum. Brown glass ampoules, cleaned with n-hexane, were filled with 20-23 g of milk powder, flushed with argon and sealed. In total 21 batches with 65 ampoules in each were produced. The ampoules were stored in the dark at (5 2)°C and a relative humidity of 50%. 

Each of the three sediments was homogenised during two weeks in a special polythene-lined mixing drum under dry argon. Following homogenisation, each sediment was bottled (ca. 40 g) in batches of 40. After each batch of bottling the contents of the... 

The dry sediment with a mean moisture content of 3.5% (calculated by drying a separate portion of sediment at 105°C for 3-4 h) was passed through a tungsten carbide-bladed hammermill and sieved to pass apertures of 90 pm. The <90 pm fraction was collected in a PVC mixing drum (filled with dry argon) and homogenised for 14 days at about 48 rpm. 

Coal 180 by manual filling after re-mixing the sample in a mixing drum filled with dry argon, which was replaced every 3 h ... 

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