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Home , Omni Processor, Waste treatment

Supercritical water oxidation (SCWO) technology for sludge and micropollutants treatment

Kobe Nagar CEO, 374Water Inc. Lead Engineer Dept. of Civil and Environmental Engineering, Duke University GLOBAL SLUDGE PROBLEM COSTS SOCIETY $BB

Wastewater Sludge in Wastewater Sludge Industrial Wastewater Developing Countries USA Sludge - USA

Current treatment creates secondary

“10 million pounds of poop from New York are stranded in a rural Alabama rail yard”

“Safe” storage and landfilling are not sustainable

It never really goes away – we just move it around… CURRENT TREATMENT METHODS ARE LIMITED

Climate Adaptable Technology Limited Treatment and excess use of non- biodegradable products ► Shifting of weather patterns around the world, causing shortages and ► GenX (PFAS), PAHs, pesticides, droughts in some areas and floods in pharmaceuticals, microplastics others. ► Nutrient pollution from land application ► By 2025, two-thirds of the world’s excess nitrogen and phosphorus population may face water shortages.

https://www.worldwildlife.org/threats/water-scarcity “We can not solve our problems with the same thinking we used when we created them” - Albert Einstein

Could SCWO be the alternative to sludge treatment?

SCWO Process + + + >374 °C ~221 Bar Organic Air Clean Lower GHG Energy Water Emissions

Sustainable, decentralized & superior on-site treatment This barrel is an The same energy as in 87 kWh 3 gallons of worth of dump! gasoline 6 Giphy.com SUPERCRITICAL WATER

SC Water has similar strength as Acetone to dissolve organic compounds Supercritical Water Oxidation (SCWO) Solution

SCWO Process + + + + + >374 °C 250 Bar Electricity Organic Waste Air Heat

SCWO converts organic waste into clean water,

heat, electricity and CO2 in seconds!

8

BREAKTHROUGH TREATMENT TECHNOLOGY

Very fast reaction (seconds) - small footprint

Complete elimination of pathogens & micro-pollutants

Energy-efficient and possibility for off-grid operation at scale

No pollution, no odor

The industrial-scale pilot unit on Duke campus can treat Can cotreat hazardous the fecal waste of ~1000 people per day industrial (oil, chemical, pharma, etc.)

Scalable and offer competitive cost to AD and other methods UN GOALS ADDRESSED Fecal slurry & septage

A TRUE disposal

Animal Cost (ROM) = CapEx + OpEx treatment Compact $$$ SCWO

$$$$ Lime stabilization $$$ Anaerobic $$$$ $$$ Drying + digestion Polluting Clean 0* $$ Incineration Dumping Anaerobic ponds, $$$ Drying beds Landfilling Land application $$ $* $$ Composting Lagoon, Sprayfield Space Intensive * Not including lawsuits LOWER COST, ENERGY, AND FOOTPRINT

Incineration SCWO

Treatment (VSR)

CapEx

OpEx

Plant Footprint

Energy consumption

Polluting emissions

Sustainable

12 WHY SCWO? WHY NOW?

Innovation • Mixing tee configuration - avoids fouling and limits corrosion • Integrated system – enables the system to run off the grid and generate electricity at a large scale • Safety – using air (vs. pure oxygen) and having the ability to limit temperature and avoid runaway reaction

Proven pilot plant • Pilot plant at Duke Campus operational since 2015 – demonstrating successful treatment various feedstocks and micro-pollutants

Demand for sustainable solutions • Running off the grid • Flooding resilient • Future proofing regulations for micro-pollutants • Phase-out of Hearth Incinerators by 2025 Our Path to Date

► Operating & ► Running with ►Reliability testing safety procedures slurries prototype A ► Construction ► New reactor ► Commercial ► Commissioning design development 2014 2016 2018-19

2013 2015 2017 ► Reactor design ► Liquids treatment ► Energy recovery ► Electrical & ► Aspen Plus investigations control design modeling ► New slurry pump ► Procurement ► Slurry handling ► Prototype B design

14 A fully functional prototype – 1 ton per day (Nix1)

15 Inside our pilot, the Nix1

16 Inside Prototype A WASTE TYPES & CALORIFIC VALUE

Dewatered Waste Primary secondary activated Food Waste sludge sludge sludge (WAS)

Dry solids: 20-30% Dry solids: 13% Dry solids: 27% Dry solids: 30% Ash content: ~27% Ash content: 18% Ash content: ~35% Ash content: 6% Calorific value: Calorific value: Calorific value: Calorific value: 16.3 MJ/kg 13.9 MJ/kg 15.7 MJ/kgdry dry dry 16-19 MJ/kgdry

We use the energy embedded in the waste to fuel the reaction no need to digest the waste first Typical Biosolids Treatment Performance

Analysis Influent Effluent Removal %

COD (mg/L) 214,000 70 99.97

Total N (mg/L) 10,875 200 98.2

NH3 (mg/L) 443 17.6 -

NO3 (mg/L) 183 15.9 -

NO2 (mg/L) 14.9 0.4 -

-3 PO4 (mg/L) 4930 67.9 98.6

pH 6.8 7.02 -

19 SLUDGE TREATMENT – TYPICAL RESULTS

WASTE (WAS) SCWO EFFLUENT

Pre-feed processing included diluting the feedstock ppm mg/l to 11.5% solids, macerating and adding co-fuel. To 70 26 reach a 180,000 mgO2/L COD, 11.5% COD Ammonia In Effluent In Effluent concentration – we added 0.05 kg of diesel and 0.44 kg of water to each kg of sludge.

After reaching a smooth consistency, the slurry was fed to the SCWO reactor using a high pressure >99% 93.7% 95.6% pump. It was preheated to 200 ºC and reacted at supercritical conditions.

VSR Nitrogen Phosphate Removal Removal Calorific value (0-20 kJ/ kg dry) COD (): high conversion of over 13.4 kJ/kg 99.9%, from 170,000ppm to 70ppm (effluent is clean water and inert minerals; after further results improve even further).

Ash content (0-40%) VSR (Volatile Solids Reduction): current technologies can reach a range of 16-40% of VSR. We reached >99% - a 34.8% standard SCWO capability.

Ammonia, Nitrogen, Phosphorous: most of the nitrogen is converted to nitrogen gas. Total nitrogen in the effluent is Solids (0-30%) 90 mg/L, phosphate level in the dry mineral output stream is 17.4% ~10% mass as P2O5. 20 pH level in effluent: 6.6 Fate of N and P and S during treatment

N Forms SCWO Exhaust • Organic Process Gas <3 ppm NH • Urea v 3 N gas <5 ppmv NOx • Ammonium 2 <3 ppmv SOx • Heterocycles

P Forms Solid minerals • Organic Phosphate precipitates

• Phosphate Ca3(PO4)2

S Forms MgNH4PO4·6H2O - • HS , COS, organic Sulfates, Hydrates • Mercaptans CaSO4 21 Treatment of Emerging Contaminants Experimental Approach • Spike trace contaminants to during IPA phase and to biosolids

Results • Ibuprofen and acetaminophen: spiked 10 mg/L each Effluent: ND at < 1 µg/L Removal > 99.99% • Triclosan: spiked: 100 µg/L Effluent: ND at < 0.1 µg/L Removal > 99.9% • PFOS: spiked: 2-6 mg/L Effluent: 5-30 µg/L Removal 98.6-99.7% • PFOA: spiked: 2-7 mg/L Effluent: 0.1-0.4 µg/L Removal > 99.8%

Emerging contaminants are well removed This reduces concerns for water 22 SCWO PFAS (FOREVER CHEMICAL) TREATMENT

We spiked a biosolids slurry with high concentrations of PFOS and PFOA before feeding it to the Supercritical Water Oxidation omni- 6.3 mg/l 7.3 mg/l processor Spiked biosolids Spiked biosolids slurry with PFOS slurry with PFOA

SCWO EFFLUENT

Effluent Analysis

6.000 > 99.7% > 99.9%

1.000

0.167 PFOS PFOA Removal Removal 0.028

0.005 Non-detect Concentration (µg/L) 4 mg/l (<0.2 ppmv) 0.001 Fluorides in liquid effluent, PFBA PFBS PFDA PFHpA PFHxA PFHxS PFNA PFOA PFOS PFPA HF (@vent) showing recovery of F ppb ng/l 0.079 0.000 0.010 0.142 0.069 0.004 0.000 0.120 5.336 0.070 atoms as F- Co-fuels and Other Wastes Co-treated with Biosolids

Tested to date in our pilot • Isopropyl alcohol (IPA) • Diesel Typical removal • Waste motor oil, vegetable oil • COD: 99-99.9% • • Total nitrogen: 50-98% • Food waste • Total phosphorous: 73-99% • Plastics waste (PET, PE)

Lessons learned • Successful treatment • Quantified impacts e.g. on emissions • Broadens scope of SCWO application • Enables synergistic opportunities

Adding waste cooking Mixing ground food oil to biosolids waste and

24 OUR VISION – DECENTRALIZED ON-SITE TREATMENT

Mixed waste streams Raw sludge & Biosolids Hazardous waste • Primary from pits or septic emptying Fecal sludge • Secondary sludge Animal waste (Digested or undigested)

Other applications • Industrial WWTP • CAPOs Sludge • Military and Emergency responses

Cluster of Buildings Communities on microgrid

Example SCWO treatment Nix6 facility in 20 ft. container One 40 ft container treats for 1000-3000 people waste from 6,000 people Energy Minerals Distilled water

CO2 (carbonation, capture) Energy Balances

Nix1 Nix6 Nix30 Nix200 (prototype) (commercial) (commercial) (commercial) (not optimized for efficiency) 5.1 ton/day 25.5 ton/day 170 ton/day Losses 1 ton/day 20 kW

26 kW 10 kW

12.5 kW 167 kW 300 kWh/day 4000 kWh/day Cost - Distributed Treatment (community to city scale solutions)

Power Distilled Total Capacity wet Estimated consumed water treatment metric ton /day Land use CapEx or produced costs (CAPEX (people*) ($/Unit) produced (ga/day) + OPEX)

Nix6 One 40’ Consumes 5.1 wet ton/day ISO 700 $2M $144 per ton 10 kW Community container Nix30 Three 40’ Produces 25.5 wet ton/day ISO 3,600 $4.5M $55 per ton 12.5 kW Town Containers

Nix200 Produces 170 wet ton/day ~5000 ft2 24,000 $17M $26 per ton 167 kW City Scale

27 IMPLEMENTATION (EXISTING WWTP)

Feed Secondary Plant Discharge/ treatment Land Application (Primary treatment)

Sludge Water Brackish Water (Option for RO) (Dewatering)

Filter & 10-15% slurry Dewatering mixed with FOG (option) to SCWO unit

Minerals SCWO Distilled (Fertilizer) Water

28 OWASA (CHAPEL HILL) CASE STUDY

Not in use / Two Nix 30 units extra capacity X

X XX X X X X X X X X X

Eliminate digestersEliminate Eliminate sludge Reduce & fermenters Boilers storage and dewatering handling 29 OWASA (CHAPEL HILL) CASE STUDY

Today With SCWO Sludge treatment capacity 2,050/ton per year 2,400/tpy Sludge treatment utility 4 Anaerobic Digestors (AD) 2 Nix30 Units Processing time 25-28 days 30 minutes Land allocated (excluding 12,000 m2 200 m2 land application) Cost Unit cost $14M $9M CapEx – Yearly (20 years, $1.3M/year $850k/year 7% interest) OpEx - Yearly $2.2M $150k Total cost per year ~$3.5M/year $1M/year Cost per wet ton >$200 $52 Savings of $2.5M/year and reduction of chemical usage

30 Conclusions • Supercritical water oxidation work and not just in the lab! • Systems engineered to treat biosolids with >99.9% VSR, generate clean water and produce power • All organics are effectively treated, including recalcitrant nitrogen and PFAS • All pathogens are eliminated (>10 log reductions) • Treatment is very cost competitive (total costs: $25-60/wet ton) • Commercial units are available for 2020-2021 Contacts Kobe Nagar [email protected] [email protected] www.374water.com Funding & Support

31 SCWO integration & synergies

Drinking Contaminated Water Water Alternatives to Biosolids Landfilling

Mixed Waste Treatment SCWO Fecal sludge and hazardous waste/solvents Additional Revenues WWTP Hot water (low grade heat) Capacity Minerals, value added Mild Expander products (eg fertilizer, PCC) Dewatering Reduce CO2 (carbonation, capture) COD/BOD load

Sewage Septage Shifting the waste paradigm 32 Supplemental Slides Additional Technical Information SCWO APPLICATION TO SWINE MANURE MANAGEMENT Loyd Ray Farms: Yadkinville NC

9 barns: 8640 pigs 370,000 gallons manure/week 17 tons COD/week 1.6 tons N/week Old lagoon 0.6 tons P/week (5 acres) Biogas: ~22 cfm Anaerobic treatment Sprayfields (~60 acres) (2 acres)

Footprint of a SCWO system that can handle all the manure: = 3 shipping containers

34 ONE-STEP CONTINOUS PROCESS

* Process and reactor design PCT patent pending 35 3636 ENVIRONMENTAL BENEFITS OF SCWO

1. Mitigation of 6 tons of CO2e per ton waste treated 2. 40% Reduction in electricity demands for treating sludges (+2 GW US) 3. Eliminates transportation emissions from hauling sludges to . 4. Reclaim 0.9 ton of water per ton waste treated 5. Reducing chemicals and additives consumption during treatment. 6. Avoid excess nutrients flow to land and surface water, thereby protecting the environment and reducing algal blooms grow

37 38 1 WORLD BANK INTENSIFIED GHG BIOGENIC CARBON State of the art, DC WATER (Blue Plains) 300mgd, serve population of 2M 153-acre water-front land, Cost $4B

57 Ton CO2e/yr per 1000 people

39 Process Schematic of the BP-AWRRF (Figure is from Willis, 2017)