Production of water from computing waste heat using solvent extraction desalination

Introduction

A leading research team from WaterLAB and Southwest Research Institute is building on scientific research on the use of solvent extraction desalination for the generation of fresh water from ultra-low grade waste heat. Directional solvents capable of separating pure water from saltwater, such as seawater and brine, have been shown to operate with heat sources as low as 70 C. For this project, a pilot system has been constructed and will be expanded into a full demonstration plant that is integrated with a bitcoin mining facility. This will result in the first fully-integrated bitcoin mining desalination system capable of efficiently using heat from computational mining, generative AI or other high-intensity compute applications to generate pure water.

Background

The internet consumes 10% of all electricity generation globally and is forecasted to double by 2030. A standard Google search consumes around 0.0003 kwh’s of electricity - with approximately 2 trillion searches conducted annually this amounts to 600M kwh’s a year (0.6 TWh) of energy. When you consider this energy footprint, the implications on fresh water use are critical. Every kwh of data center usage requires 1.8 gallons of water for cooling - 10B gallons of water a year, not including the power generation. If AI were integrated with every internet search, energy increases by a factor of 10 (0.003-0.004 kwh’s) - so too does water consumption. Bitcoin mining is another form of high-intensity computing that consumes large amounts of energy and water - the optimist view is this is an opportunity, rather than a fatal flaw, to leverage emergent markets to develop new water supplies based on advanced desalination (ref).

Technology

The primary obstacle to the development of desalination for computing applications like bitcoin mining is the low quality of the heat generated, despite the quantity. The quality of heat is bound by the upper-temperature limits of computing devices (computers), which is typically below 85°C. Existing low-temperature desalination processes are established and available - under vacuum conditions a heat source at 50°C can power a desalination process with reasonable conversion efficiency. However, creating a vacuum requires additional electrical energy for the vacuum pumps, making it less than ideal for applications where waste heat is the only energy source. Reverse osmosis (RO) also requires electricity for pressure.

Solvent extraction desalination (SED) is a new water separation process that utilizes only low-grade heat and does not require electric power. SED operates at atmospheric pressure and as a result is very low capital cost. Thermal solvents switch their water solubility sharply with a modest change in temperature and readily absorb water by rejecting salt. Because they are also non-aqueous, they naturally separate and when heated to 60-70 C, release water. This makes them ideal for low temperature thermal desalination.

SOLVENT EXTRACTION DESALINATION FOR SEPARATION OF WATER FROM BRINE (REF)

Project

The project team has completed baseline design and process modeling and has successfully conducted bench-scale economic validation of solvent extraction desalination (pic). This project will further this research by building a fully-integrated pilot-scale SED system to be tested on saltwater under varying conditions, using recovered waste heat. The pilot system will process one gallon per minute (1 gpm) of brine at 30,000 – 70,000 ppm of total dissolved solids (salt concentration). Once fully operational, the SED system will be installed at a location where thermal energy (heat) can be recovered from bitcoin mining and used as the sole energy supply for the SED system. The project duration is 24 months for design, procurement, construction and validation of the pilot system, followed by 12 months of testing, data collection and cost analysis.

IP

The intellectual property rights to this project will be minted as an IP NFT (Intellectual Property Non-Fungible Token). An IP-NFT is a unique digital asset that uses blockchain to represent ownership over the intellectual property generated from scientific research. The purpose of IP-NFT’s is to accelerate scientific progress by democratizing ownership, allowing anyone to purchase a stake in the IP rights. This in turn creates a new avenue for funding research that is outside the confines of traditional funding institutions. The IP-NFT for this project represents ownership of the background solvent IP (ref) as well as specific IP that will be generated for the integration of solvent desalination with waste heat recovery from bitcoin mining.

Budget

Overall funding for the project budget is broken down into engineering design, materials and testing;

$100,000 Engineering & Design

$40,000 Pilot Plant Materials

$312,000 Testing & Operations

$452,000 Total Project Budget

Production of water from computing waste heat using solvent extraction desalination

Production of water from computing waste heat using solvent extraction desalination

Topics

DOI