DRYING BT MEANS OF AIR AND STEAM. Explanations, Formulae, and Tables for Use in Practice. Translated from the German of B. Hausbrand. Two folding Diagrams and Thirteen Tables. Crown 8vo. 1901. 72 pp. Price 5s.; India and Colonies, 5s. 6d.; Other Countries, 68.; strictly net.
Contents. Preface. — British and Metric Systems Compared— Centigrade and Fahr. Thermometers. — Chapters I., Introduction. — II., Estimation of the Maximum Weight of Saturated Aqueous Vapour which can be contained in 1 kilo, of Air at Different Pressure and Temperatures. — III., Calculation of the Necessary Weight and Volume of Air, and of the Least Expenditure of Heat, per Drying Apparatus with Heated Air, at the Atmospheric Pressure: A, With the Assumption that the Air is Completely Saturated with Vapour both before Entry and after Exit from the Ai»paratus.— B. When tlM Atmospheric Air is Completely Saturated before entry f but at its exit is only^, } or J Saturated. — C, When the Atmospheric Air is not Saturated with Moisture before Entering the Drying Apparatus. — IV., Drying Apparatus, in which, in the Drying Chamber, a Pressure is ArtiBciafly Created, Higher or Lower than that of the Atmosphere. — V., Drying by Means of Superheated Steam, without Air. — VI, Heating Surface, Velocity of the Air Current, Dimensions of the Drying Room, Surface of the Drying Material, Losses of Heat. — Index.
EVAPORATING, CONDENSING AND COOLING AP- PARRATUS. Explanations, Formulae and Tables for Use in Practice. By B. Hausbrand, Engineer. Translated from the Second Revised German Edition by A. C. Wright, M.A. (Oxon.), B.Sc. (Lond.), formerly Assistant Lecturer and Demonstrator in Chemistry at the Yorkshire College, Leeds. With Twenty-one Illustrations and Seventy-six Tables. Demy 8vo. 1902. Price 10s. 6d.; India and Colonies, lis.; Other Countries, 12s.; net.
Contents. Preteces. — List of Tables. — Metric and British Systems and Thermometers compared. — Symbols and Contractions. — Introduction.— Chapters I., Coefficient of Transmission of Heat, ky, and the Mean Temperature Difference, Bjm. — II., Parallel and Opposite Currents. — III., Apparatus for Heating with Direct Fire. — IV., The Injection of Saturated Steam. — V^ Superheated Steam. — VI, Evaporation by Means of Hot Liquids. — VII., The Transference of Heat in General, and Transference by means of Saturated Steam in Particular. — VIII., The Transference of Heat from Saturated Steam in Pipes (Coils) and Double Bottoms* — IX., Evaporation in a Vacuum. — X., The Multiple-effect Evaporator. — XI., Multiple-effect Evaporators from which Extra Steam is Taken.— XII., The Weight of Water which must be Evaporated from 100 Kilos, of Liquor in order its Original Percentage of Dry Materials from 1-25 per cent, up to 20-70 per cent. — XIII., The Relative Proportion of the Heating Surfaces in the Elements of the Multif^ Evaporator and their Actual Dimennons. — XIV., The Pressure Exerted by Currents of Steam and Gsis upon Floating Drops of Water. — XV., The Motion of Floating Drops of Water upon which Press Currents of Steam.— XVI., The Splashing of Evaporating Liquids. — XVII., The Diameter of Pipes for Steam, Alcohol, Vapour and Air.— XVIII., The Diameter of Water Pipes.— XIX., The Loss of Heat from Apparatus and Pipes to the Surrounding Air, and Means for Preventing the Loss. — XX., Condensers. — XXI., Heating Liquids by Means of Steam. — XXII., The Cooling of Liquids. — ^XXIII., The Volumes to be Exhausted from Condensers by the Air-pumps. — XXIV., A Few Remarks on Air-pumps and the Vacua they Produce. — XXV., The Volumetric Efficiency of Air-pumps. — XXVI., The Volumes of Air which must be Exhausted f^om a Vessel in order to Reduce its Original Pressure to a Certain Lower Pressure. — Index.
Key Takeaways
- Understanding the principles of heat and moisture exchange is crucial for effective material drying.
- Different atmospheric conditions affect the efficiency of air-based drying processes.
- Superheated steam can be used to dry materials without the need for air.
Practical Tips
- Use tables provided in the chapter to calculate necessary heating surface areas for efficient drying.
- Consider using superheated steam for faster and more energy-efficient drying processes.
- Monitor temperature differences closely when transferring heat through pipes or coils.
Warnings & Risks
- Improper use of high-pressure steam can lead to equipment damage and safety hazards.
- Failure to account for atmospheric conditions may result in inefficient material drying.
Modern Application
While the chapter focuses on industrial-scale drying methods, its principles remain relevant today. Modern survivalists can apply these techniques to dry food or other materials efficiently using available resources such as solar heaters or propane burners.
Frequently Asked Questions
Q: What are the key factors in calculating the necessary weight and volume of air for a drying apparatus?
The chapter explains that one must consider atmospheric pressure, temperature, and moisture content both before entry into and after exit from the drying chamber to calculate these parameters accurately.
Q: How does superheated steam contribute to material drying without air?
Superheated steam can be used directly for drying materials by transferring heat efficiently. This method is particularly useful in environments where air-based drying may not be feasible or efficient.
Q: What are the dimensions of pipes required for steam and water based on the chapter's content?
The chapter provides detailed tables to determine the appropriate diameter of pipes for steam, alcohol, vapor, air, and water. These dimensions ensure optimal heat transfer and efficiency in drying processes.