A method and a system for comminuting and cleaning waste plastic are described. For this purpose, waste plastic is comminuted and pre-washed in a wet mill and then cleaned in a washing system. The resulting wastewater is subjected to mechanical filtration and flotation and then temporarily stored as circulating water. Based on this, some of the circulating water is returned to the wet mill as first process water and some of the circulating water is returned to the washing system as second process water. In this way, the first and second portions of the circulating water may be specifically adapted to the respective water requirements of the wet mill and the washing system as well as to the required water qualities, if necessary with selective post-cleaning of the second portion of the circulating water. As a result, the fresh water requirement for the process described may be minimized.

A water treatment system includes an equipment system including each water treatment device that executes a water treatment process and a control apparatus that controls each water treatment device, and a management system including a management apparatus that determines a control content of the water treatment process by using a virtual system obtained by virtualizing each water treatment device and controls the water treatment process of the equipment system based on the control content via the control apparatus of the equipment system.

A process for continuously treating a stream of water (for example, a stream of oil and gas well wastewater) to remove contaminants therefrom is provided. The process comprises: a) testing the stream of water to determine if it contains biological matter and, if necessary, removing biological matter from the stream; b) testing the pH level of the stream and, if necessary, adjusting the pH level of the stream; c) separating the stream of water into a sludge discharge stream and a separator unit effluent stream; d) separating the separator unit effluent stream into a steam discharge stream and a concentrated brine stream; and e) separating the concentrated brine stream into a chlorine gas stream and at least one of a sodium stream and a calcium stream. A corresponding system is also provided.

A dynamic multi-objective particle swarm optimization based optimal control method is provided to realize the control of dissolved oxygen (S.sub.O) and the nitrate nitrogen (S.sub.NO) in wastewater treatment process. In this method, dynamic multi-objective particle swarm optimization was used to optimize the operation objectives of WWTP, and the optimal solutions of S.sub.O and S.sub.NO can be calculated. Then PID controller was introduced to trace the dynamic optimal solutions of S.sub.O and S.sub.NO. The results demonstrated that the proposed optimal control strategy can address the dynamic optimal control problem, and guarantee the efficient and stable operation. In addition, this proposed optimal control method in this present invention can guarantee the effluent qualities and reduce the energy consumption.

An efficient and low-cost process for gravity thickening and fermentation of waste activated sludge withdrawn from the surface of an activated sludge aeration basin for use with treatment systems designed for “enhanced biological phosphorus removal” (EBPR). One or more reactor tanks are used for the process with the steps of: A fill cycle, in which the waste mixed liquor flows into the tank, followed by a settle cycle, in which the mixed liquor is allowed to settle for a period of time, followed by a decant cycle, in which the clear liquid is withdrawn. The withdrawal of a volume of the settling mixed liquor for discharge is then followed by a ferment period for the remaining settled mixed liquor solids and a transfer of the fermented mixed liquor solids back to the activated sludge liquid stream process.

The invention relates to a method for cleaning a sensor in a wastewater monitoring arrangement comprising at least one sensor with a sensor surface, such as an optical sensor with a window, lens, or the like. In the monitoring arrangement, during a normal operation mode, a sample flow of wastewater is arranged to flow past the sensor surface and the sensor is arranged to provide measurement values that describe a quality parameter of the wastewater. The method comprising steps of: starting a sensor cleaning cycle by discontinuing the sample flow; starting a cleaning liquid flow; arranging the cleaning liquid flow towards the sensor surface; mechanically cleaning the sensor surface by an automatic cleaning device; discontinuing the cleaning liquid flow after a predetermined cleaning time and ending the cleaning cycle; and starting the wastewater flow again.

The present invention provides a sewage treatment biological agent and a preparation method and application thereof. The sewage treatment biological agent according to an embodiment of the present invention includes an induced nucleus. The induced nucleus has good bioaffinity. A microbial flora can be attached to the induced nucleus to achieve rapid growth. As the microbial flora gathers and grows on the induced nucleus, the granulation is gradually achieved by the sewage treatment biological agent to facilitate the sewage treatment. The microbial flora grows on the induced nucleus, and the growth process of microbial flora is a covering growth process which starts from the induced nucleus and gradually expands outward and centers on the induced nucleus. During the growth of microbial flora, extracellular polymers are secreted, which can further promote the granulation process by the sewage treatment biological agent.

The present disclosure relates to the technical field of wastewater treatment in oil and gas field operations, in particular to a method for synergistic degradation treatment of polysaccharide-containing polymer wastewater by controllable —OH radical. In this method, a ferrous ion solution, an alkaline solution, and an oxidant solution are mixed and heated to generate —OH radicals, —O radicals and polymeric iron ions, etc., which then is mixed with polysaccharide-containing polymer wastewater. The generated highly oxidative —OH radicals and —O radicals react with polysaccharide polymers so that they are degraded. The generated polymeric iron ions form flocs that purify the suspended solids in the wastewater. The purified polysaccharide-containing polymer wastewater can be re-injected or reused as an oilfield working fluid. In the present disclosure, the polysaccharide-containing polymer wastewater can be treated in a quick and efficient manner, and the treated wastewater can be recycled.

A method for phosphorus removal and recovery using an organic carbon source of urban sewage, including: first filling a biofilm reactor with sewage; stirring under anaerobic conditions, phosphorus being released from a polyphosphate biofilm using an organic carbon source in the sewage; discharging a portion of the sewage after the aforementioned treatment into a recovery tank and storing same as a recovery liquid; performing aerobic aeration on the remaining part of the sewage after anaerobic treatment, such that phosphorus is absorbed by the polyphosphate biofilm until the concentration of phosphorus reaches a requirement for discharge; turning off the aeration device and discharging the sewage; returning the recovery liquid to the biofilm reactor, simultaneously adding sewage to fill the reactor, and repeating the aforementioned steps multiple times; and obtaining a phosphorus recovery liquid when the concentration of phosphorus in the recovery liquid reaches the requirements for a phosphorus recovery process.

The present invention provides a process for continuous treatment of high-concentration organic wastewater and a device for continuous treatment of high-concentration organic wastewater. The process of the present application is that: high-concentration organic wastewater is continuously separated through the synergistic interaction of a multilayer evaporator and a heat pump, and the generated wastewater steam containing light components is continuously subjected to desulfurization and catalytic combustion after being mixed with air in a gaseous form, the treated wastewater can meet discharge standards, and heavy components of the generated wastewater can be recycled. After the desulfurizing agent in a first desulfurizer and the catalyst in a first catalytic combustor are deactivated, the generated wastewater steam containing the light components can be switched to a second desulfurizer and a second catalytic combustor for reaction, and air can be introduced into the deactivated catalyst and desulfurizing agent for in-situ regeneration at a high temperature.