US-12618359-B2 - System and method for diluting vapor and generating electricity

Abstract

A system and method for converting hazardous waste vapors into renewable and reusable energy is disclosed. The system comprises a generator, a compressor operable to pressurize vapors to a selected threshold range, and a gas storage system configured to store and feed the fully pressurized vapor to the generator at a steady state.

Inventors

• Brian Connor
• Sam Rayford Turner

Assignees

• Audubon Engineering Company, L.P.

Dates

Publication Date

20260505

Application Date

20231214

Claims (6)

1. 1 . A method for converting a vapor of volatile organic compounds into reusable energy, the method comprising the steps of: separating liquids and particulates from an unfiltered vapor of volatile organic compounds to create a purified vapor; compressing the purified vapor to a threshold pressure range to form a fully pressurized vapor, storing the fully pressurized vapor in a gas storage system comprising a plurality of interconnected tanks configured to operate interchangeably to disperse a steady state of the pressurized vapor, feeding the fully pressurized vapor from the gas storage system to a common gas skid, enriching the fully pressurized vapor with an amount of natural gas in the common gas skid based on a predetermined combustion ratio to form a fuel mixture, performing regular testing on the fully pressurized vapor exiting the gas storage system and the resultant fuel mixture exiting the common gas skid to determine the combustion ratio for the fuel mixture, adjusting natural gas supply to ensure resultant fuel mixture remains constant at the combustion ratio; and combusting the fuel mixture in the generator to create electricity.
2. 2 . The method of claim 1 , wherein the generator is a microturbine.
3. 3 . The method of claim 2 , further comprising the step of providing a heat recovery system operatively coupled to the microturbine.
4. 4 . The method of claim 3 , further comprising the step converting an exhaust gas from said microturbine into reusable energy using the heat recovery system.
5. 5 . The method of claim 2 , wherein the threshold pressure range is 50-75 PSIG.
6. 6 . The method of claim 2 , wherein the fuel mixture comprises 30-45% natural gas.

Description

RELATED APPLICATIONS This application is a continuation of U.S. application Ser. No. 18/134,259, filed Apr. 13, 2023, which claims priority to U.S. Provisional Application No. 63/330,566 filed Apr. 13, 2022. The entire contents of the above application are hereby incorporated by reference as though fully set forth herein. FIELD The present application relates to the field of vapor recovery systems. More specifically, the present invention relates to systems for converting recoverable vapors into renewable and reusable energy. BACKGROUND As a result of the global demand for trading and exchanging crude oil and its derivatives, like gasoline, these commodities are often stored before being transported from one place to another or used. During storage, gases from the liquid oil separate and rise to the top forming vapors made of volatile organic compounds (“VOC”), which are also commonly referred to as “fugitive emissions.” In the case of crude oil, these gases largely are made from methane, which is harmful to the environment. In order to control the emissions of these gases, a variety of systems have been developed to dispose of these emissions, including systems incorporating a flare, vapor recovery units (“VRUs”), or vapor combustion units (“VCUs”). VRUs utilize a carbon bed and blowers as a means of recovery for Gasoline/Transmix, but these systems have several drawbacks. VRUs create maintenance expenses as the carbon beds have to be replenished on a routine 1-2 year interval. VRUs utilize a knockout pot, blowers, multiple pumps, and extensive piping arrangement for operation. VRUs are inefficient and typically provide minimal volume return based on the throughput of loading (for example, 1000 gallons were transferred and 1 gallon of product was recovered by means of VRU with Carbon Bed). As a result, VRUs are slowly being serviced out and replaced with VCUs. VCUs provide 99.9% destruction of VOCs but still create harmful emissions and do not include a mechanism for converting these waste byproducts into renewable energy. VCUs traditionally were developed off propane and natural gas and due to newer CO/CO2 emissions requirements will be utilizing natural gas only. VCUs utilize a smaller ratio of natural gas (20-30% methane) to vapor to dilute the contaminants found in vapor. The combustion happens in an atmospheric state inside the vapor combustion stack. VCUs operate intermittently, so only when loading, and therefore use significant natural gas for intermittent startup/shutdown. VCUs for truck or rail racks inject natural gas at the upstream point of combustion, and for the marine loading cases, they inject at both the point of loading and combustion. VCUs combust natural gas mixed with vapor in an atmospheric state using a fresh source of ambient oxygen by means of an induction fan into the stack. As a result, these VCUs produce large quantities of CO and CO2 emissions with no means of after-treatment or means of capturing nitrogen or sulfur species. While VCUs and VRUs have minimized harmful emissions when compared to prior alternatives, there is always a need for systems that further reduce pollution and increase energy efficiencies. BRIEF SUMMARY OF THE INVENTION It is the object of this invention to provide a system that converts hazardous vapors into a renewable energy source while simultaneously lowering harmful emissions. The system comprises a feeding system operatively coupled to a combustion system. The feeding system includes a vapor byproduct source capable of producing hydrocarbon vapors and a means for separating any liquids or particulates from the hydrocarbon vapor to create a purified vapor. The combustion system includes a compressor operable to pressurize the purified vapor to a select pressure range, a means for enriching the purified vapor with a select percentage of natural gas to form a fuel mixture, and a generator operable for converting the combined fuel mixture into electricity. The combustion system may utilize a microturbine as a generator in combination with a fuel storage system, eductor, and a calorimeter and density meter to ensure maximum efficiency while using the microturbine based on select input ranges for fuel composition and pressure. In an alternative embodiment, the system includes a heat recovery system capable of capturing and converting exhaust gases from the generator into renewable energy using, for example, a heat pump and a generator. Optionally, a continuous emission monitoring system analyzer may be used to analyze exhaust emissions from the generators of the system to ensure compliance with environmental emission standards. In an alternative embodiment, a method for converting hydrocarbon vapors into renewable energy is disclosed. The method comprises the steps of producing a hydrocarbon vapor from a vapor byproduct source, separating liquids and particulates from the hydrocarbon vapor to create a purified vapor, compressing the purified vapor to a se