NOTES ON DRYING AND DRIER OPERATION1

A brief résumé is given, comparing drying shrinkage with the action of clay slaking in a bank. The drying of Missouri dry-press refractories in summer versus winter and blistering and mcans of prevention are discussed. The operation of three Harrop type driers and an ordinary waste-heat tunnel drier are described.     

NOTES ON THE OPERATION OF DIRECT FIRE TUNNEL KILNS1

The successful application of the direct fire car tunnel type kiln in firing of semivitreous chinaware is described. The bisque kiln firing to cone 9 one-half down is 332 feet 11 inches long, the placing height at middle of crown being 6 feet and the placing width 5 feet 1 inch. The glost kiln operating at cone 5 has the same placing height and width as the bisque but the length is 301 feet 1 inch long. The ware is placed in saggers as formerly. Natural gas is used as fuel and is supplied to kiln through Maxon Premix burners; an auxiliary fuel oil system can be used in case the gas is not available. After a year's operation some of the important concliisions drawn are as follows:

• 1 The heat distribution is not ideal.
• 2 There is no appreciable difference in labor cost a t this plant than in the older ones.
• 3 There is a considerable saving in fuel.
• 4 The sagger loss is much less than in the older type plants.
• 5 The direct fire tunnel kiln has proven siiccessful from the commercial standpoint in manufacturing semi-vitreous china.

     

NOTES ON CYANITE AND DIASPOR REFRACTORIES1

This investigation covers a survey of some cyanite, diaspor, and clay refractories. The work is divided into three phases: (1) diasporcyanite study, (2) diaspor-clay and cyanite-clay study, and (3) commercial production and tests. Results of routine tests made with each set of test specimens are given. The addition of 20% or more cyanite to diaspor tends to counteract the shrinkage of diaspor during continued use at high temperatures.     

NOTES ON KALLAUNER AND SEGER METHODS OF RATIONAL ANALYSIS1

A comparison of the Seger, Kallauner, and calculated rational analysis is made, using a Florida kaolin and a Tennessee ball clay. Results obtained are observed and discussed.     

NOTES ON SHAPE CONSTRUCTION1

The lines of development of a course for training ceramic artists, who are very much in demand, are outlined. Ceramic shape design for quantity production involves a study of factory processes, product specifications, both consumer's and factory, and manufacturing specifications. Examples of commercial designing are demonstrated, using drawings of a series of glass designs as illustrations for various points made. The filing of research studies in design, relation of shapes to product specification, and product development are discussed. The difference between the art engineer and the craftsman is pointed out.     

NOTES ON CASTING SLIP1

This is a note showing the unreliability of viscosimeter control for casting slip. A rule is given for control of the “hardness” and thickness of slip.     

NOTES ON FIRING TERRA COTTA1

Some notes are given on the firing behavior of a 14-foot diameter muffle type terra cotta kiln, using coal as a fuel. The need of more data on periodic fired kilns in all branches of the ceramic field is stressed.     

氨气压缩机组润滑油系统运行问题及改进措施

以煤制甲醇装置氨气压缩机组为例,介绍其润滑油系统和干气密封系统,分析机组运行过程中存在漏油、干气密封进油等问题的原因,提出相应解决措施,实施后效果良好。     

NOTES ON TERRA COTTA BODY SHRINKAGE1

Notes on method of preparing a terra cotta body, proportioning by volume and using unground material, and method of preparing body, proportioning with ground materials, using disc feeders, are given. Notes on checking laboratory work with these two methods and variation in shrinkage due to amount of water in the body are also considered.     

NOTES ON SHIVERING OF TERRA COTTA1

Six terra cotta clays are tested for shivering as a body trouble using a white mat glaze, at cone 3 starting. One non-shivering clay and one badly shivering clay are experimented with, to produce and overcome shivering. Causes of Shivering .—From this work and that of others which has been checked, uses are

• 1 presence of finely divided silica in the body, from

• (a) highly siliceous clays
• (b) finely ground grog of a siliceous nature

• 2 presence of soluble salts in the clay, grog, or tempering water
• 3 longer firing periods

Methods of Eliminating Shivering.

• 1 Use of a flux such as feldspar, felsite, or similar rock to overcome action of fine silica
• 2 Use of coarse grog or sand
• 3 Use of barium carbonate to overcame effects of salts

     

NOTES ON TERRA COTTA GLAZE CONSISTENCY1

Some of the difficulties encountered in applying glaze to terra cotta are discussed. The use of a hydrometer to test glazes is misleading as a hydrometer supplies gravity indication only in true solutions and glazes are not true solutions; furthermore the viscosity of a glaze may obscure the real specific gravity. It is suggested that in order to Control a glaze it should first be made to a desirable specific gravity and then the desired viscosity at that gravity be ascertained by experiment. A viscosimeter and specific gravity bottle are suggested for this purpose. The effect of change of alkalinity and of bacteria together with the control of glaze wastage are also discussed.     

尿素装置解吸水解运行总结及优化操作

总结解吸水解目前的工况，分析解吸塔进料浓度增加、进料温度偏低等问题，提出解决措施。     

PDMBR和SFDMBR用于污水处理的运行特性比较

采用孔径37 μm涤纶滤布制作膜组件,构成一体式自生动态膜生物反应器(SFDMBR),和以高岭土为预涂剂,组成预涂动态膜生物反应器( PDMBR),研究两者用于处理模拟生活污水的运行特性.结果表明,PDMBR抗膜污染效果比SFDMBR的好,PDMBR和SFDMBR的运行周期分别为13、11d,两者的膜通量基本稳定在28 L·m-2·h-1.当DO质量浓度大干0.5 mg·L-1时,DO对PDMBR和SFDMBR的COD去除几乎没有影响,对COD的击除率均在85％以上;PDMBR和SFDMBR的EPS浓度分别稳定在70、75 mg·L-1.     

NOTES ON FIRING IN DOWNDRAFT PERIODIC KILNS1

The results of a series of investigations chiefly in connection with firing are presented, with a general discussion of factors entering into the heat treatment of silicate materials. These include (1) factors controlling firing, (a) specific heat of the clay body, (b) heat of dissociation of the hydroxides, (c) latent heat of fusion, and (d) heat of reactions which take place under fusion, (2) fuel consumption and temperature rise, (3) heat distribution in the kilns, (4) firing economies, (5) cooling, and (6) dehydration and shrinkage.