Abstract: An anaerobic digester for use in wastewater treatment systems having a fixed cover including a central tower for controlling gas and foam. A constant operating level is maintained in the digester by utilization of an overflow weir located in the tower. The fixed cover having an under flat surface that is in direct contact with contents of the digester. The tower has a number of spray nozzles that operably direct movement of foam toward discharge locations.

Abstract: A composition and method for producing a multiple boiling point ether gasoline component is provided. A mixed alcohol composition including predominantly C.sub.1 -C.sub.3 alcohols is reacted with an alkene stream to produce a mixture of ethers having different boiling points. The ether mixture is useful, when blended with gasoline, to increase oxygenation and overall motor fuel performance.

Abstract: A process for making a portion of a temporary mold capable of producing several prototype plastic parts, including using computer-aided design to produce a geometric computer model of a prototype part suitable for being molded in plastic, and using this computer model in a rapid prototyping system, such as a stereolithography system, to produce a mold portion from plastic material. The mold portion has an inner surface substantially complementary to an outer surface of the intended plastic part. Solid support is provided for the mold portion to prevent any flexing thereof in later operation. The mold portion inner surface is coated with a layer of metal such as nickel having a thickness of between 75 and 150 .mu.m, which layer has an inner surface adhered to the mold inner surface and an outer surface of the precise shape and dimensions for forming the plastic parts.

Abstract: A two-part concave-convex rupture disc for use in a safety pressure relief device comprises one part which is perforated with lines of small holes that introduce controlled weakness in the disc and the other part which acts as a seal. When the pressure in a fluid on the convex side of the discs exceeds a predetermined limit, the discs will reverse their direction of convexity and the metal of which the perforated disc is made will tear cleanly along the lines of perforation and rupture so as to release the fluid in which the excess pressure occurred. The pressure at which the rupture occurs is determined by the choice of the size and spacing of the perforating holes, as well as the choice of the thickness, the material of which the discs are made, and the pressure used to form the discs.

Abstract: An organo metallic complex catalyst, useful in the hydroformylation of an olefin, e.g., an alkene, to yield an aldehyde product in which the normal aldehyde isomer predominates over branch-chain isomers, which has the structure: ##STR1## wherein capital M is a Group VIII metal (preferably rhodium); Q is phosphorus, arsenic, or antimony (preferably phosphorus); and R is phenyl or a lower alkyl group.In the process employing the new catalytic complex is not necessary to employ an excess of any ligand, and moderate reaction conditions are adequate. The catalyst can be prepared ex situ or in situ from a suitable source of rhodium or the Group VIII metal and a suitable derivative of ferrocene.

Abstract: An organo metallic complex catalyst, useful in the hydroformylation of an olefin, e.g., an alkene, to yield an aldehyde product in which the normal aldehyde isomer predominates over branch-chain isomers, which has the structure: ##STR1## wherein capital M is a Group VIII metal (preferably rhodium); Q is phosphorus, arsenic, or antimony (preferably phosphorus); and R is phenyl or a lower alkyl group.In the process employing the new catalytic complex it is not necessary to employ an excess of any ligand, and moderate reaction conditions are adequate. The catalyst can be prepared ex situ or in situ from a suitable source of rhodium or the Group VIII metal and a suitable derivative of ferrocene.

Abstract: In a process for the manufacture of trioxane by the distillation of aqueous formaldehyde solutions which are intimately mixed with an immiscible, non-volatile, oily liquid phase, the improvement comprising using a monoalkyl ether of a polyoxyalkylene glycol as the oily phase.