An apparatus and method are proposed for controlling the number of active individual trays used in a stacked tray type vortex grit removal system as a function of flow conditions and performance requirements. In accordance with exemplary embodiments, a flow control arrangement for a stacked tray type vortex grit removal system is configured to include a bypass system which is able to selectively block one or more trays from receiving influent during low flow conditions. In one form, the bypass system may comprise one or more hinged blocking plates positioned at the entrance to selected trays, where the blocking plates may be individually activated to either allow flow to enter the associated tray, or block the movement of the flow. Other types of blocking plates (for example, sliding plates) can be used instead of hinged plates.

A passive filter cell having a basin with a floor and two or more vertical or upright sidewalls forming chute or container having first or left sidewall, second or right sidewall, and third or back sidewall, and fourth or front downwardly curved sidewall, an inlet positioned proximate a top of the fourth or front sidewall and an outlet positioned proximate the top of the third or back sidewall, wherein the floor is configured angled from the fourth or front sidewall to the third or back sidewall, discharge pipe positioned proximate junction between the floor and the third or back sidewall, and lip configured to extend from the top of the third or back sidewall into an interior of the basin.

Some embodiments of the technology disclosed herein relate to a system having a hydrodynamic separator element defining an element inlet and an element outlet. The element outlet has a first element outlet and a second element outlet. The hydrodynamic separator element has a plurality of curved microfluidic channels in fluid communication. Each of the plurality of microfluidic channels are arranged to operate in parallel. Each microfluidic channel defines a channel inlet downstream of the element inlet and a channel outlet having a first channel outlet upstream of the first element outlet and a second channel outlet upstream of the second element outlet. A flow characteristic sensor is in sensing communication with the separator element. A controller is in data communication with the flow characteristic sensor, where the controller is configured to provide a first alert upon the flow characteristic being outside a first threshold.

A sedimentation device for separating a solid-liquid suspension has a settling tank, a feed well, a feed pipe, an overflow collector and a mixing area. A pump is disposed in the overflow collector and overflow from the overflow collector can be fed through the pump to the mixing area. The solid-liquid suspension to be clarified can be diluted without affecting the sedimentation process, the chemicals can be used to the optimum, and the amount of overflow fed to the mixing area can be exactly determined.

Some embodiments of the technology disclosed herein relate to a system having a hydrodynamic separator element defining an element inlet and an element outlet. The element outlet has a first element outlet and a second element outlet. The hydrodynamic separator element has a plurality of curved microfluidic channels in fluid communication. Each of the plurality of microfluidic channels are arranged to operate in parallel. Each microfluidic channel defines a channel inlet downstream of the element inlet and a channel outlet having a first channel outlet upstream of the first element outlet and a second channel outlet upstream of the second element outlet. A flow characteristic sensor is in sensing communication with the separator element. A controller is in data communication with the flow characteristic sensor, where the controller is configured to provide a first alert upon the flow characteristic being outside a first threshold.