The present invention provides a method for preparing a composition comprising highly concentrated antibodies by ultrafiltration in batch concentration mode having a first constant feed rate step and a second controlled feed rate step.

The present invention provides a method for preparing a composition comprising highly concentrated antibodies by ultrafiltration in batch concentration mode having a first constant feed rate step and a second controlled feed rate step.

A spiral wound module assembly including: a plurality of spiral wound modules aligned within a pressure vessel with a first module located adjacent the first end and a second module located adjacent the second end, a flow plate including opposing first and second sides positioned within the pressure vessel between the first spiral wound module and the first end of the pressure vessel with the first side facing the first spiral wound module and the second side facing the first end, and wherein the flow plate includes a plurality of holes passing from the first side to the second side which create a pressure drop in fluid passing from the first spiral wound module and the closer of the feed inlet port and concentrate outlet port; and a differential pressure sensor adapted to measure differences in pressure between fluid located on the opposing sides of the flow plate.

A method for controlling a membrane distillation system includes determining whether there is a day time or a night time at a location of a solar collector system associated with the membrane distillation system; applying a first control mode during the day time to a flow velocity of a feed used by the membrane distillation system; and applying a second control mode, different from the first control scheme, during the night time, to the feed. The first control scheme is a model-free mode.

The present invention relates to a system and process for treating a feedwater wherein the system includes at least one or nanofiltration unit that receives a feed under high pressure and produces a concentrate that is directed to and held at low pressure in a concentrate accumulator. Generally the permeate or the inlet feedwater is maintained at a constant flow rate. Periodically the system is switched from a mode 1 or normal operating process to a mode 2 where the concentrate is drained from the concentrate accumulator. However, in mode 2, the feedwater is still directed into the system and through the RO or nanofiltration unit which produces the permeate and the concentrate.

The invention relates to an ultrafiltration unit for continuous buffer or medium exchange, a method for continuous buffer or medium exchange in the ultrafiltration unit, and a plant in particular for (semi)continuous production of biopharmaceutical and biological macromolecular products in particular, such as proteins, e.g. monoclonal antibodies and vaccines, comprising the ultrafiltration unit according to the invention.

A water treatment system according to an embodiment of the present invention includes a tank that stores water to be treated, a crossflow filtration membrane module that filters the water to be treated, a supply passage through which the water to be treated is supplied from the tank to the filtration membrane module by using a supply pump, and a recirculation passage through which the water to be treated, the water having passed through a membrane upstream side of the filtration membrane module, is recirculated to the tank. The tank has an upper space above a liquid surface of the stored water to be treated, the upper space being hermetically filled with an inert gas. The water treatment system further includes a gas transport passage through which the inert gas is introduced from the upper space into the supply passage or the filtration membrane module, and a compressor that is disposed in the gas transport passage and that pressurizes the inert gas. The compressor is preferably a water-sealed compressor.

[Object] To provide a method for isolating and purifying a minute useful substance. [Solution] Disclosed is a method for isolating and purifying a minute useful substance. The method includes filtering a liquid containing a minute useful substance through a hollow fiber membrane. The hollow fiber membrane has an inner diameter of 0.2 mm to 1.4 mm and a molecular weight cut-off of 100000 to 1000000. The filtering includes a first filtration process of press-fitting the liquid containing the minute useful substance from a first opening on one end side of the hollow fiber membrane and filtering the liquid to separate the liquid into a permeate and a first concentrate, and a second filtration process of press-fitting the first concentrate from a second opening on the other end side of the hollow fiber membrane and filtering the first concentrate to separate the first concentrate into a permeate and a second concentrate. A concentrate is produced in which a concentration of the minute useful substance is increased by filtration in which the first filtration process and the second filtration process are alternately performed a plurality of times at a membrane surface velocity of 0.3 m/sec to 2 m/sec.

A diafiltration system comprises a fluid treatment assembly comprising two or more fluid treatment modules, the fluid treatment assembly comprising a feed inlet, a permeate outlet, and a retentate outlet; each module comprising a cross flow treatment assembly including an ultrafiltration membrane and having a feed side and a permeate side, and a diafiltration fluid distribution plate comprising a diafiltration fluid feed inlet and a common feed permeate/diafiltration fluid permeate outlet port; two or more diafiltration fluid conduits, each conduit in fluid communication with a respective single diafiltration fluid feed inlet; and, a diafiltration fluid pump comprising at least a first multiple channel pump head having at least two channels including separate channels for separate conduits in fluid communication with respective single diafiltration fluid feed inlets, wherein the pump provides simultaneously controlled diafiltration fluid flow rates through each of the conduits to the respective diafiltration fluid feed inlets.

A control method and system for controlling the operation of a seawater injection system comprising at least one water treatment line in which seawater is forced through one or more coarse filtration unit(s), ultrafiltration unit(s) and at least one of a reverse osmosis unit and/or a nanofiltration unit to a water injection pump, and wherein the flowrate required to create differential pressure across membrane(s) of the ultrafiltration unit(s) is obtained by a boosting pump. A controller C implemented operation control is applied to adjust automatically the outlet pressure and flow of the boosting pump such that an average flowrate through the ultrafiltration units is maintained and determined as boosting pump flow divided by the number of active ultrafiltration units. A proportional-integral-derivative control mechanism is preferably applied to all adjustable flow/pressure regulating units in the seawater injection system.