Abstract: A charged depth filter for removing cells and/or cellular debris from a biopharma feedstock having a first functionalized nonwoven layer having a first calculated pore size and a first dynamic charge capacity; a second functionalized nonwoven layer having a second calculated pore size and a second dynamic charge capacity positioned after the first functionalized nonwoven layer in the direction of the biopharma feedstock flow, and wherein the first calculated pore size is greater than the second calculated pore size, and the first dynamic charge capacity is less than the second dynamic charge capacity.

Abstract: An improved refrigeration system that has an air cooled condenser exposed to outdoor ambient conditions and which automatically maintains sufficient head pressure during cooler weather for adequate liquid flow to the expansion valve of the evaporator by backflooding the condenser. Sub-cooling of the liquid in the condenser results from the backflooding and this sub-cooled liquid flows into the liquid line to the expansion valve. The liquid line out of the receiver joins the liquid line below the receiver so that the pressure in the receiver can be used to maintain the liquid level and the presence of liquid at the condenser. Means is provided to control the refrigerant pressure in the receiver in response to liquid level in the outlet line from the condenser.

Abstract: An improved refrigeration system that has an air cooled condenser exposed to outdoor ambient conditions and which automatically maintains sufficient head pressure during cooler weather for adequate liquid flow to the expansion valve of the evaporator by backflooding the condenser. Sub-cooling of the liquid in the condenser results from the backflooding and this sub-cooled liquid is diverted through a bypass line around the receiver to a sub-receiver and thereby to the liquid line to the expansion valve. In warmer weather, the liquid or a liquid and gaseous mixture from the condenser can enter the receiver or the bypass line. The liquid line out of the receiver forms a drop leg and joins the bypass line at the sub-receiver at a sufficient elevation below the receiver so that the pressure due to the static head at the sub-receiver is greater than the pressure at the receiver, said pressure difference causing any gaseous and liquid mixture from the condenser to flow to the receiver.

Abstract: A control system for a compression type refrigeration unit with an air-cooled condenser exposed to outside ambient conditions. In cooler weather the head pressure is maintained by backflooding the condenser which limits the condensing surface. This also subcools the liquid in the condenser. A bypass line from a point between the outlet of the condenser and the receiver inlet connects with the liquid supply line leaving the receiver and directs this subcooled liquid to the expansion valve. A solenoid valve in the bypass line is controlled by a liquid level sensor or subcooling sensor in the line leaving the condenser. This increases the capacity of the evaporator as less evaporation is required to remove the sensible heat-down to the evaporating temperature. In warmer weather, the system automatically reverts to a conventional condensing mode.