A system for controlling an environment within a fuel tank is provided. The system includes a conduit with a plurality of vents, wherein the conduit defines a path through the fuel tank, and wherein the conduit is configured to direct a flow of air along the path and out the plurality of vents.

A system for controlling an environment within a fuel tank is provided. The system includes a conduit with a plurality of vents, wherein the conduit defines a path through the fuel tank, and wherein the conduit is configured to direct a flow of air along the path and out the plurality of vents.

Provided is a breather pipe structure for a liquid reducing agent storage tank which ensures that a liquid reducing agent can be supplied without trouble even if a breather pipe in the liquid reducing agent storage tank is clogged with frozen liquid reducing agent. In a breather pipe structure for a liquid reducing agent storage tank (10) which stores a liquid reducing agent (5) and which has a breather pipe (20) for introducing/discharging air attached on top of the liquid reducing agent storage tank (10), a lower end (20c) of the breather pipe (20) in the liquid reducing agent storage tank (10) is arranged to extend along a liquid reducing agent defrosting piping (16) provided in the liquid reducing agent storage tank (10).

A method of delivering proppant to a well site has the steps of transporting a load of proppant in a vessel to a desired location, moving the load of proppant from the vessel into a container so as to create a proppant-loaded container, unloading the proppant-loaded container into a pneumatic bulk trailer, and transporting the unloaded proppant in the pneumatic bulk trailer to well site. The container is placed onto a bed of a truck and moved in proximity to the vessel. The proppant-loaded container is placed onto a tilting mechanism and then tilted so that the proppant is discharged through a flow gate of a container into a hopper. The proppant in the hopper can then be conveyed to the pneumatic bulk trailer.

A method of delivering proppant to a well site has the steps of transporting a load of proppant in a vessel to a desired location, moving the load of proppant from the vessel into a container so as to create a proppant-loaded container, unloading the proppant-loaded container into a pneumatic bulk trailer, and transporting the unloaded proppant in the pneumatic bulk trailer to well site. The container is placed onto a bed of a truck and moved in proximity to the vessel. The proppant-loaded container is placed onto a tilting mechanism and then tilted so that the proppant is discharged through a flow gate of a container into a hopper. The proppant in the hopper can then be conveyed to the pneumatic bulk trailer.

A system comprises a non-transitory machine readable storage medium storing instructions and a database identifying a plurality of assets and a state of each asset. The instructions configure a processor for receiving updates to a distributed electronic ledger managed by plural peer processors. Each update includes an event or change affecting one of the assets. The peer processors verify portions of the ledger describing each event or change. At least one of the updates has not yet been recorded in the ledger at a time of the receiving. The processor computes a state of each asset, based on the updates, receives a request for a state of one of the assets; and responds to the request, reflecting each event and change affecting that asset. The response is performed without waiting for the peer processors to verify an update that has not yet been recorded in the ledger.

A liquid tank system comprises a main liquid tank, an outlet communicating between a fluid circuit and the main liquid tank, an inlet communicating between the fluid circuit and the main liquid tank, and an auxiliary cavity. First vent passage and second vent passage(s) communicate between the main liquid tank and the auxiliary cavity and allows liquid and gas to flow from the main liquid tank to the auxiliary cavity. The second vent passage has a flow control device regulating flow through the second vent passage and having a set point at which it allows liquid and gas to flow from the main liquid tank to the auxiliary cavity only when a pressure in the main liquid tank is beyond a threshold. The liquid tank system has an attitude envelope in which the liquid tank system is configured such that, in use, the flow control device blocks flow through the second vent passage when an end of the first vent passage in the main liquid tank is above a liquid level, and the flow control device allows gas and/or fluid flow through the second vent passage when main fluid tank pressure is above the threshold and the end of the first vent passage in the main liquid tank is below the liquid level.

A liquid tank system comprises a main liquid tank, an outlet communicating between a fluid circuit and the main liquid tank, an inlet communicating between the fluid circuit and the main liquid tank, and an auxiliary cavity. First vent passage and second vent passage(s) communicate between the main liquid tank and the auxiliary cavity and allows liquid and gas to flow from the main liquid tank to the auxiliary cavity. The second vent passage has a flow control device regulating flow through the second vent passage and having a set point at which it allows liquid and gas to flow from the main liquid tank to the auxiliary cavity only when a pressure in the main liquid tank is beyond a threshold. The liquid tank system has an attitude envelope in which the liquid tank system is configured such that, in use, the flow control device blocks flow through the second vent passage when an end of the first vent passage in the main liquid tank is above a liquid level, and the flow control device allows gas and/or fluid flow through the second vent passage when main fluid tank pressure is above the threshold and the end of the first vent passage in the main liquid tank is below the liquid level.

A method of delivering proppant to a well site has the steps of transporting a load of proppant in a vessel to a desired location, moving the load of proppant from the vessel into a container so as to create a proppant-loaded container, unloading the proppant-loaded container into a pneumatic bulk trailer, and transporting the unloaded proppant in the pneumatic bulk trailer to well site. The container is placed onto a bed of a truck and moved in proximity to the vessel. The proppant-loaded container is placed onto a tilting mechanism and then tilted so that the proppant is discharged through a flow gate of a container into a hopper. The proppant in the hopper can then be conveyed to the pneumatic bulk trailer.

A system and method removes well fluids, which include gas and liquids, from a storage tank. The storage tank has a gas relief valve that opens to admit atmospheric air into the storage tank when the pressure of a gas cap decreases below a vacuum threshold pressure. Well fluids flow into the storage tank and the level of liquid is monitored. When the level reaches a first level, a pump is operated by a controller to remove liquid from the storage tank. The pressure in the gas cap is monitored while the pump is operating. The speed of the pump is adjusted to maintain the gas cap pressure above the predetermined pressure and avoid the introduction of atmospheric air into the gas cap.