The present invention provides a tail water decentralized treatment and drainage system of sewage treatment plant, comprising a riparian vegetation buffer zone, a subsurface flow constructed wetland and a riverside protection pile, the riparian vegetation buffer zone comprises an excavation protection slope and an ecological bag paved on the excavation protection slope. The subsurface flow constructed wetland is disposed on the river protection slope along the river flow direction, the subsurface flow constructed wetland is provided with a treatment system, a water drainage system and a plurality of outlet pipes disposed along the river flow direction. The present invention is novel in idea and reasonable in design. By constructing a subsurface flow constructed wetland on the slope of the river bank after repositioning, the vegetation buffer zone and the subsurface flow constructed wetland are skillfully combined, and the tail water of sewage treatment plants is purified and treated through the subsurface flow constructed wetland. It is particularly suitable for changing the condition of single drainage outlet for the sewage treatment plant constructed near the river, with strong practicability.

Systems, devices, and methods for providing nutrient removals in an up flow filtration storm water system for treating water to very high clean levels using filtration media. A filtration media supported by a screen above an angled floor in a vault allows for incoming storm water to pass into a void space above the angled floor into the screen and filtration media and then out an outlet to the vault. The filtration media can include recyclable and/or natural particles. Layers of river rocks can be placed on top of and below the filtration media. Water sprayers can further liquefy sediment and debris that fills the void space between the angled floor and the bottom of the screen. The captured debris can slide down the angled floor, where a vacuum hose from an above ground vacuum truck can remove the debris and sediment. The long lasting filtration media can be cleaned by being backwashed.

Provided herein are portable apparatus as well as methods of analyzing an injection fluid using these portable apparatus. In some embodiments, the injection fluid can contain a polymer, but a polymer is not necessary. For example, the portable apparatus and methods may be used to determine viscosity, long term injectivity, filter ratio, or any combination thereof of the injection fluid.

A method of filtering a main fluid using a rotary fluid filter. A 360 degree filtration cycle is initiated by receiving, at an initial position, a first portion of a main fluid at a front end of a first fluid flow passage extending through a filter body rotationally mounted within a housing. The filter body is rotated in a rotation direction and the first portion of the main fluid is discharged from a rear end of the first fluid flow passage, having passed through a filter received in the first fluid flow passage. The filter body is rotated further in the rotation direction and a first portion of a backwash fluid is received through the first fluid flow passage from the rear end to the front end. The rotational cycle is completed by rotating the filter body back to the initial position.

Devices and methods associated with these devices for significantly reducing or eliminating liquid (e.g., water) in a water or wastewater treatment unit above the underdrain from moving downwardly into the underdrain during an air only wash cycle of the treatment unit. The treatment unit can take many forms including but not limited to an upflow filter and a downflow filter. The treatment unit may include a filter bed having one or more layers of filter media supported by gravel above the underdrain. The treatment unit may also include an underdrain having a porous plate, slotted plate or slotted upper structure that obviates the need for gravel. Positive pressure is provided to the underdrain to overcome the downward force of the driving head in the treatment unit to significantly reduce or prevent liquid present in the treatment unit above the underdrain from moving downwardly into the underdrain.

A system includes a sand filter disposed within a tank. A pipe connected to the tank is configured to flow fluid in or out of the tank. The system includes a valve configured to selectively allow fluid to flow through the pipe and a flowmeter configured to measure a flow rate of fluid through the pipe. An automatic control unit includes one or more processors and a non-transitory computer readable medium storing instructions executable by the one or more processors to perform operations including determining a debris accumulation status for the sand filter based in part on flow measurements from the flowmeter, and determining a failure status of the valve based in part on flow measurements from the flowmeter.

A paving element includes upper and lower surfaces and one or more drainage channels extending through the paving element between the upper and lower surfaces. The drainage channels include a substantially concave or cupule shaped upper portion, provided on the upper surface of the paving element, and a channel from the concave portion through to the lower surface of the bottom surface of the paving element. The drainage channels can be complete, when provided in the interior of the paving element, or partial, when provided along the sides or perimeter of the paving element. The partial channels are completed when the paving element is placed adjacent another paving element when forming a pavement. The drainage channels are adapted to facilitate the cleaning process of the channels.

A river course ecological treatment system essentially comprises a plurality of ecological biological water purification systems and a plurality of plastic retaining dams disposed along a river course, and at least one damp land ecological water purification system disposed beside the river course. The plastic retaining dams separate the river course into several retaining regions. The ecological biological water purification systems purify the water in the retaining regions by microorganism purification. Afterward, the water purified by the ecological biological water purification systems is introduced into rainwater channels of the at least one damp land ecological water purification system. After being purified by aquatic plants in the at least one damp land ecological water purification system, the water returns to the retaining regions the downstream portion of the river course. Therefore, a river improvement system capable of performing both step-by-step treatment and joint treatment is effectuated.

A method and an apparatus for treating a liquid containing impurities may include a filtering chamber configured to permit granular media to interact with liquid containing impurities, thereby removing impurities from the liquid to produce filtrate; a filtrate section for receiving the filtrate; a gas supplying system for delivering gas to the granular media in the filtering chamber for transport of a portion of the granular media to a granular media washer; a reject section in fluid communication with the granular media washer for receiving a reject mixture comprising liquid and impurities from the granular media washer; and a control unit that is configured to determine whether the portion of the granular media is being transported properly based on an amount of reject mixture in the reject section.

Provided herein are portable apparatus as well as methods of analyzing an injection fluid using these portable apparatus. In some embodiments, the injection fluid can contain a polymer, but a polymer is not necessary. For example, the portable apparatus and methods may be used to determine viscosity, long term injectivity, filter ratio, or any combination thereof of the injection fluid.