Systems and methods for controlling wellsite equipment, including a cementing unit comprising a plurality of sensors operable to generate information related to operational status of the cementing unit and a controller comprising a processor and a memory including computer program code. Communication is established between the cementing unit and the controller. The controller is operable to operate the cementing unit to automatically perform: a pressure calibration of the cementing unit, a pressure test of the cementing unit, an over pressure shut-down test of the cementing unit, a low rate pumping test of the cementing unit, a hydraulic horsepower test of the cementing unit, and/or a mixing test of the cementing unit.

The efficiency of water disinfection can be significantly increased by supplying the ozone in combination with oxygen to an inlet of a cavitation pump or a line atomizer. A compressor can be introduced at an inlet of the cavitation pump or the line atomizer, compressing the gas mixture at a pressure higher than the pressure within pump or the atomizer. The compressed gases are provided to the inlet of the atomizer or the pump, where the compressed gases mix with the water and enter the cavitation pump or the line atomizer (where most of the dissolution of the gases happens). The compressor allows to increase the amount of oxygen and ozone provided to the pump or the line atomizer, increasing their dissolved concentration. In addition to the disinfecting properties, the higher level of oxygen correlates to an improved taste of the water.

The invention provides methods for assessing one or more predetermined characteristics or properties of a microfluidic droplet within a microfluidic channel, and regulating one or more fluid flow rates within that channel to selectively alter the predetermined microdroplet characteristic or property using a feedback control.

A water purification apparatus includes a water inlet; a medicine mixing device in fluid communication with the water inlet; and a water outlet interconnected to the medicine mixing device and a dental treatment center. The medicine mixing device includes a medicine storage for storing antiseptic solution, a mixing unit interconnected to the water inlet, the water outlet, and the medicine storage, and a controller interconnected to the water inlet and the medicine storage. The controller includes a sensor and a microprocessor. The controller sends the antiseptic solution from the medicine storage to the mixing unit and controls a volume of water flowing from the water inlet to the mixing unit. The microprocessor instructs the controller to control a volume of the antiseptic solution supplied from the medicine storage to the mixing unit based on a signal sensed by the sensor.

The present invention is a device and a method that combines a carbon disulfide-releasing chemical with a low pH organic or inorganic acid to produce a carbon disulfide-containing fluid at or near the point of injection that minimizes or eliminates the possible exposure of carbon disulfide to workers and the environment. In one particular embodiment a positive displacement injection pump injects the carbon disulfide-containing fluid into a crude oil system for treating crude oil transmission lines and in downhole tubulars to remove paraffin deposits. The device uses a unique in-line motion mixer to mix two fluids. The device is electronically controlled locally and remotely with the system operating data displayed locally and transmitted remotely. The paraffin treating carbon disulfide-containing fluid and supplemental chemicals dissolve, disperse and remove paraffin deposits.

The present disclosure provides a system for producing carbon dioxide (CO.sub.2)-dissolved deionized water (DIW), the system comprising: a DIW source for providing DIW; a CO.sub.2 source for providing CO.sub.2; a pressurized tank, coupled to the DIW source and the CO.sub.2 source, the pressurized tank being arranged for generating CO.sub.2-dissolved DIW with a first concentration according to the DIW of the DIW source and the CO.sub.2 of the CO.sub.2 source; a mixer, coupled to the DIW source and the pressurized tank, the mixer being arranged for generating CO.sub.2-dissolved DIW with a second concentration according to the CO.sub.2-dissolved DIW with the first concentration and the DIW of the DIW source; and wherein the second concentration is lower than the first concentration.

A fluid preparation system includes a tank, a chemical supply line, a mixer, and a deionized (DI) water supply line. The tank contains a first chemical solution. The chemical supply line is coupled to the tank and configured to supply the first chemical solution. The mixer is coupled to the tank. The DI water supply line is coupled to the mixer and configured to supply DI water. The first chemicals solution and the DI water are mixed at the mixer to generate a second chemical solution.

A method of preparing a concrete composition for downhole injection includes utilizing a controller to control a process including circulating process water in a process water supply loop for a predetermined period while monitoring and controlling the temperature and flow rate of the process water, circulating aqueous-based air entrainment solution in an aqueous-based air entrainment solution supply loop for the predetermined period and controlling the flow rate of the aqueous-based air entrainment solution and after the predetermined period of time in which the flow of process water and aqueous-based air entrainment solution have stabilized, simultaneously actuating valves to divert and mix the process water, the aqueous-based air entrainment solution and compressed air to produce an air-entrained foam and mixing the foam with a concrete composition to be deployed downhole.

The efficiency of water disinfection can be significantly increased by supplying the ozone in combination with oxygen to an inlet of a cavitation pump. The ozone and the oxygen are turned into ultra-fine bubbles via cavitation action within the pump, facilitating the dissolution of the oxygen and ozone within the water. The water mixed with the oxygen and the ozone is subsequently supplied to a line atomizer, where the dissolution of the ozone within the mixture is completed. The combined use of the cavitation pump and the line atomizer can lead to a substantially complete dissolution of the supplied ozone within water that needs to be disinfected, allowing to easily achieve the concentration of ozone necessary for water disinfection. Due to this efficiency, the system and method described are highly scalable and suitable for water purification at water purification plants of various sizes.

Provided herein are gas mixing systems, comprising a gas inlet for receiving two or more gases and a mixing chamber with a static mixer for mixing the gases. Preferred mixing chambers further comprise a reduced pressure compartment downstream of the static mixer that is in fluid communication with the gas inlet. A gas outlet is in fluid communication with the mixing chamber, and one or more sensors are coupled to the reduced pressure compartment and are configured to continuously sense various parameters such as barometric pressure and the percentage of oxygen in the gas mixture moving through the mixing device. Most typically, the readings of the sensor are pre-compensated for temperature, pressure, and humidity. Also provided herein are methods for using the same.