Method and installation (100) for providing a batch of fresh concrete having a temperature in a predetermined temperature range at a remote point of use, whereby a control unit (140) controls at least one step of cooling of cement and/or aggregate and/or mixing water before mixing and/or of the fresh concrete, during the production of the batch.

The invention provides compositions and methods directed to carbonation of a cement mix during mixing. The carbonation may be controlled by one or more feedback mechanisms to adjust carbon dioxide delivery based on one or more characteristics of the mix or other aspects of the mixing operation.

The subject invention provides a portable warm asphalt preparation apparatus and a process for the production of warm asphalt. In addition to a source of granular plastic and a source of mineral aggregate that, together form an asphalt feed material, the apparatus comprises a first receptacle having an inlet for introducing the asphalt feed material into a chamber, a floor at an inclined plane, and an outlet for discharging asphalt from the chamber. A source of heat supplies heat to the asphalt feed material. The apparatus also has a conveyer for mixing the asphalt feed material and transporting a resultant warm mixture towards the outlet. The apparatus further comprises a temperature sensor for measuring the temperature within the chamber, and a controller that activates or deactivates the heater based on input from the temperature sensor.

Compositions and methods are provided for a system in which liquid carbon dioxide, or a mixture of liquid and gaseous carbon dioxide, is converted to solid carbon dioxide by exiting an orifice at a sufficient pressure drop, e.g., for delivery of carbon dioxide to a concrete mixture in a mixer.

Compositions and methods are provided for a system in which liquid carbon dioxide, or a mixture of liquid and gaseous carbon dioxide, is converted to solid carbon dioxide by exiting an orifice at a sufficient pressure drop, e.g., for delivery of carbon dioxide to a concrete mixture in a mixer.

A method and plant for cooling a mixture of concrete, includes: loading in a hermetically sealed tank a given quantity of ingredients to form the concrete, the ingredients including a predetermined quantity of water; regulating the pressure in the tank to obtain a transitory degree of vacuum in the tank; regulating the pressure inside a hermetically sealed condensation chamber to obtain a basic degree of vacuum in the condensation chamber that is greater than the transitory degree of vacuum, such that the pressure in the condensation chamber is lower than the pressure in the tank; operatively connecting the tank and the condensation chamber to substantially equalize the internal pressure in the tank and in the condensation chamber to a resulting degree of vacuum and to cause at least partial evaporation of the water from the tank towards the condensation chamber to lower the temperature of the ingredients in the tank.

The device and procedure for cooling fresh concrete at elevated temperatures enable efficient cooling of fresh concrete, which is achieved by the subject device comprising of: cooling station (1) with measuring and regulating equipment (2) and safety equipment (3), solenoid valves (5), pressure transmitter (6), cryogenic shut-off valves (7), collector (17) made of stainless steel pipes with temperature probes (8), concrete mixer (9) and manometer (10) with safety valves (11). The procedure of cooling fresh concrete using liquid nitrogen in the mixer is carried out as follows: first aggregate-separated gravel is added, then cement, then water and finally, if necessary, additives-chemical additives. Mixing of added raw materials lasts from 15-20 seconds, until a homogeneous mixture is obtained, after which liquid nitrogen is added at a pressure of 6 bar, giving cooled fresh concrete on which no surface cracks and fissures appear at external temperatures of 30-35 C.