Abstract: The process of the present invention relates to the isolation and purification of both a natural mixed carotenoid product and an all-trans-&bgr;-carotene product from various different biomass sources, preferably from algae of the genus Dunaliella. More particularly, the present invention relates to a single solvent process whereby both natural and colorant products lie along the same process line. The nutritional product contains the natural array of carotenes and xanthophylls found in the plant material, while the colorant product contains primarily trans-&bgr;-carotene.

Abstract: The subterranean treatment apparatus and methods disclosed herein are useful for treating various waste streams, including municipal and industrial streams. The disclosed apparatus and methods are particularly useful in determining and controlling the temperature of the reaction zone in a deep well reaction apparatus while avoiding fouling of thermocouples and permitting easy service and replacement. In the disclosed embodiment, a fluid quiescent zone is created in the heat exchanger of the treatment apparatus located within the reaction zone and the temperature is used to control the system by operation of the heat exchanger or control of the C.O.D. of the influent.

Abstract: A process for effecting chemical reactions, including wet oxidation reactions, in a deep well or down-hole reactor preferably providing a crosscurrent flow in a nested tube configuration wherein the influent fluid is in heat transfer relation with the effluent fluid. The disclosed process includes flowing an influent fluid including the reactants downwardly through a downcomer pipe which extends below ground in a subterranean opening or well casing forming a hydrostatic column of fluid, which defines a predetermined pressure, with the reactants at a temperature sufficient to initiate and maintain the desired chemical reaction. The method then includes flowing the effluent fluid upwardly through an upcomer pipe to ground level, preferably in heat transfer relation with the downflowing influent fluid. The method of this invention includes boiling the effluent fluid in the upcomer pipe, thereby reducing the hydrostatic fluid pressure in the upcomer and increasing the mass flow rate.