Abstract: A flowable food product or other substance is heated or chilled by pumping it through a long, slender tube on a continuous basis in one direction only while simultaneously subjecting it to a temperature differential. The body of product contained within and moving through the tube is segmented into a number of discrete, end-to-end but longitudinally spaced-apart sections by plugs that are periodically introduced into the tube and moved along with the product. The plugs continuously scrape the wall of the tube free of any accumulation of frost or cooked-on material without interrupting the continuous flow and without subjecting the product to deleterious shear stresses. The frequency of plug insertion can be varied without changing the rate of product flow along the wall of the tube so that the best combination of temperature, speed, and scraping frequency can be achieved for each product formulation on a custom basis.

Abstract: Apparatus including a tubular outer member having a baffle plate positioned therein downstream from the point of injection of gas into said tubular outer member. The baffle plate contains vanes for directing gas spirally to the inner walls of the pipeline to be cleaned. Abrasive material, usually sand, is introduced into the device through a line passing through the center of the baffle plate secured thereto so that the line and the baffle plate may be removed from the tubular outer member as a unit.

Abstract: A system of pressure gauges and pipeline arrangement is described for metering abrasive materials into a gas stream for subsequent injection into a pipeline to be cleaned.