公开(公告)号：US11406940B2

公开(公告)日：2022-08-09

申请号：US16498201

申请日：2018-03-29

Applicant: BL TECHNOLOGIES, INC.

Inventor： Jianwen Zhai ,  Min Luo

IPC: B01D61/02 ,  B01D61/08 ,  C02F1/44 ,  C02F101/12

Abstract: This specification describes a method for lowering the content of monovalent ions in a final concentrate of a nanofiltration system relative to a brine and a corresponding nanofiltration system. The nanofiltration system comprises at least three stages of nanofiltration, wherein the concentrate from each segment flows into the next segment. A feed stream is sent into one stage to generate a concentrate stream, and a first portion of the concentrate stream is recirculated to the one stage. The pH of the feed stream is controlled in a range of 2-7. The temperature of the feed stream is in a range of 20-60° C. The feed stream includes the recirculated concentrate stream and at least part of a concentrate generated from an upstream stage. The method and the system described herein can reduce the concentration of monovalent ions in the final concentrate during a nanofiltration separation process.

公开(公告)号：US11027989B2

公开(公告)日：2021-06-08

申请号：US16653615

申请日：2019-10-15

Applicant: BL TECHNOLOGIES, INC.

Inventor： Jianwen Zhai

IPC: B01D61/02 ,  B01D61/14 ,  B01D65/08 ,  C02F1/44 ,  B01D61/58 ,  B01D63/10

Abstract: A membrane filtration system with reverse osmosis (RO) or nanofiltration (NF) elements is adapted to provide high recovery from difficult wastewater. The system has a plurality of stages. The system is configured to provide concentrate staging. The last stage also has concentrate recirculation. The valves and pumps of the system are arranged such that the order of flow and a recirculation pump may be switched between the first stage and the last stage at some times.

公开(公告)号：US10532938B2

公开(公告)日：2020-01-14

申请号：US14775821

申请日：2013-03-14

Applicant: BL Technologies, Inc.

Inventor： Jianwen Zhai

IPC: C02F1/44 ,  B01D61/02 ,  B01D61/58 ,  B01D63/10 ,  B01D61/14

Abstract: A membrane filtration system with reverse osmosis (RO) or nanofiltration (NF) elements is adapted to provide high recovery from difficult wastewater. The system has a plurality of stages. The system is configured to provide concentrate staging. The last stage also has concentrate recirculation. The valves and pumps of the system are arranged such that the order of flow and a recirculation pump may be switched between the first stage and the last stage at some times.

公开(公告)号：US10995016B2

公开(公告)日：2021-05-04

申请号：US16653614

申请日：2019-10-15

Applicant: BL TECHNOLOGIES, INC.

Inventor： Jianwen Zhai

IPC: B01D61/58 ,  B01D63/10 ,  B01D65/08 ,  C02F1/44 ,  B01D61/02 ,  B01D61/14

Abstract: A membrane filtration system with reverse osmosis (RO) or nanofiltration (NF) elements is adapted to provide high recovery from difficult wastewater. The system has a plurality of stages. The system is configured to provide concentrate staging. The last stage also has concentrate recirculation. The valves and pumps of the system are arranged such that the order of flow and a recirculation pump may be switched between the first stage and the last stage at some times.