Abstract: A tubular high efficiency, non-contaminating fluid heater includes an elongate tubular member having a coil-like configuration and a sidewall which defines an elongate tubular chamber formed from an inert material through which fluid is adapted to flow. The tubular member includes an inlet and an outlet and a plurality of elongate electrical resistance heaters sheathed with the same inert material are disposed in said tubular chamber for heating the fluid as it flows through the tubular chamber.

Abstract: An on-line slurry ash monitoring system for evaluating the composition of coal slurries in coal preparation plants. A coal slurry is introduced into a sample reservoir where it is removed and passed through a closed loop slurry transport system which causes the sample to be directed through a sensor and recirculated back to the reservoir. In order to enhance sensor accuracy, a sample is exposed to vacuum pressure conditions which removes gas bubbles and dissolved gases from the sample. The sensor is preferably a radiation absorption type in which characteristic absorptions of coal particles, ash and iron are evaluated by associated electronics to provide an output of slurry composition.

Abstract: A flexible electric heating assembly for immersion heating of highly corrosive liquids, such as electroplating solutions, includes an iron-nickel-chronium resistance element disposed within a thin-walled stainless steel tube and electrically insulated therefrom by a magnesium oxide ceramic. The tube is enclosed in a tubular casing in direct contact with the tube and formed of resilient electrical insulating material having a low surface coefficient of friction and a high resistance to heat and attacks by corrosive liquids or vapors, e.g., polytetrafluroetylene. The ends of the tube terminate withn a non-corrosive junction box located outside the liquid to be heated, and in which box the connections between the power supply and heating element terminals are made.