Methods and apparatus for controlling a characteristic of a cement slurry at a cementing unit, including regulating a characteristic of the cement slurry employing a closed loop feedback arrangement in the cementing unit, and adjusting a gain of the closed loop feedback arrangement in response to sampling an error of the characteristic.

A quality assurance system for mixing a slurry comprising at least water or other liquid and at least one flowable wet or dry mass, such as cement, sand or other suitable component, has computerized control over the loading of ingredients and has an accurate and broadly variable speed control of the loading of the ingredients. The mixing chamber has scales that provide a signal indicating the current weight of an ingredient in the mixing chamber. As the desired weight of an ingredient is added to the mixing chamber, the computer slows and then stops the inflow of the current ingredient being loaded via broadly variable control of the loading of the ingredients. The broadly variable control of the loading rate of the ingredients allows more accurate control of the final weight of each ingredient added. Further, a damping period allows system vibrations to dissipate, allowing highly accurate weights to be measured. Accurate records of the addition of each ingredient are maintained using the internal computer that controls the invention. The combination of highly accurate control over the input of materials added to the mixing chamber as well as the maintenance of permanent records concerning each batch of cementitious slum made allows the production of precision batches of final products to meet exacting specifications needed in both ordinary projects and highly specialized projects requiring cementitious products. Data recorded during production operations further allow accurate identification of manpower needs of projects and allow owners/operators at job sites to record, control, predict and manage production costs and manpower needs. All recorded data is transmitted to an offsite location for management to use as needed for quality and management control and can be transmitted at any time or hatch interval desired by management.

A process and system are provided for preparing seed mixes having a target quantity and a target ratio of different types of seeds. The process generally includes portioning quantities of different types of seeds from bulk supplies of the seeds, and combining the portioned quantities of seeds to prepare the seed mixes. The system generally includes first and second dispensing assemblies for portioning the quantities of the different types of seeds from the bulk supplies, and a mixing assembly for receiving the portioned quantities of seeds as the seed mixes. The combined quantities of the different types of seeds in the seed mixes are substantially equal to the target quantity, and a ratio of the quantities of the different types of seeds is substantially equal to the target ratio.

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.

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.

A vehicle CO.sub.2 capture and utilization system includes a concrete mixer vehicle and a vehicle exhaust capture system. The concrete mixer vehicle comprises a vehicle exhaust and a mixer tank. The vehicle exhaust capture system is located onboard the concrete mixer vehicle. Additionally, the vehicle exhaust capture system includes one or more fluid pathways that fluidly couple the vehicle exhaust and the mixer tank.

A vehicle CO.sub.2 capture and utilization system includes a concrete mixer vehicle and a vehicle exhaust capture system. The concrete mixer vehicle comprises a vehicle exhaust and a mixer tank. The vehicle exhaust capture system is located onboard the concrete mixer vehicle. Additionally, the vehicle exhaust capture system includes one or more fluid pathways that fluidly couple the vehicle exhaust and the mixer tank.

The present disclosure involves systems and methods for applying CO2 to concrete, which may be performed in-situ or through a separate, stand-alone process. According to another embodiment disclosed herein, a system and method for applying CO2 to one or more materials used in the production of concrete is also provided.

An apparatus (1) for producing fluid concrete comprising: a first mixer (100) configured to mix at least water (A1) and cement (C) so as to make a low fluidity concrete (2), having consistency class S2, a truck mixer configured to mix the low fluidity concrete (2) with further water (A2) so as to make a fluid concrete (3) having consistency class S2, a water supply means and at least a cement supply means configured so that said apparatus (1) can produce fluid concrete (3), a control and adjustment unit (4), connected to the water supply means and at least to the cement supply means, configured to selectively control and adjust the introduction of water (A1) and cement (C) into the first mixer (100) and the introduction of further water (A2) into the cement mixer.

This disclosure describes volumetric mobile powder mixer (VMPM) systems and methods for VMPM operation and use. The VMPM is providing with a number of storage compartments (or bins) for liquid or solid ingredients including at least one powder storage bin, a powder transport system, a dust handling system, a solid/liquid mixing system, a cellular foam generator, a product delivery system, and a controller capable of monitoring the delivery and mixing of each of the ingredients, as well as the discharge of the final product. The controller determines if the proper mixture is being discharged by the VMPM and, if not, alerts the VMPM operator. In an automated embodiment, the VMPM controller is also configured to independently control the delivery and mixing of each of the ingredients, as well as the delivery of the final product.