# Plan a CO₂ supply, from cylinders to a bulk tank

> Turn how much CO₂ you use into what suppliers quote on: a month of high-pressure cylinders, liquid cylinders, microbulk or a bulk tank at your volume, the grade and documents, and a specification to send.

An interactive planner at https://millsheet.forevenza.com/co2-supply/. The buyer states their use in one sentence (amount, unit, period, use, busiest-month uplift, delivery point, start date, and whether they would lease or own storage). The page converts it to lb, metric tonnes, US tons and standard cubic feet. It then draws a month at the buyer's site for each supply mode (high-pressure cylinders, liquid cylinders, a microbulk tank and a bulk tank), one tick per fill, against three limits the buyer sets: vessel changes a week, deliveries a month, and the longest one fill should last (beyond it a vessel is oversized). It names the mode with the fewest fills inside every limit and ends with a numbered request-for-quotation sheet to send to suppliers.

The same calculation is available as data: GET https://millsheet.forevenza.com/co2-supply/plan.json with any of these query parameters:

- `amount` (number), `unit` (lb, kg, t, ston, scf), `per` (day, week, month, year)
- `use` (beverage, food, greenhouse, water, industrial, other), `site`, `start` (YYYY-MM-DD), `peak_pct` (busiest month, % above average), `equipment` (compare, lease, own), `potable` (yes or no; with use=water, asks suppliers to state AWWA B510 conformance and NSF/ANSI/CAN 60 certification, with a certificate of analysis per load)
- `cylinder_lb`, `dewar_lb`, `microbulk_lb`, `bulk_tons` (vessel sizes; defaults are typical sizes with sources)
- `max_swaps_week`, `max_deliveries_month`, `max_fill_days` (the site's own limits)
- `show` (cylinder, dewar, microbulk, bulk_tank): the mode to put on the sheet; omitted, the fewest-fills mode inside every limit

Worked example (20 metric tonnes a month, beverage use, delivered to Fresno, CA): 44,092 lb a month, 1,449 lb a day. By mode: High-pressure cylinders 881.8 fills a month (each lasts 0.8 hours; over), Liquid cylinders (dewars) 106.5 fills a month (each lasts 6.9 hours; over), Microbulk tank 58.8 fills a month (each lasts 12.4 hours; over), Bulk tank 1.6 fills a month (each lasts 19.3 days; fits). On the sheet: Bulk tank.

## The specification it produces

```
Request for quotation: carbon dioxide, bulk tank supply

01 Product and grade: Carbon dioxide, beverage grade: ISBT quality guidelines, CGA G-6.2 quality verification level G, H or I, 99.9% purity or more
02 Volume: 44,092 lb a month (20 metric tonnes; 1,449 lb a day on average)
03 Delivery point: Fresno, CA
04 Start: to be agreed
05 Supply mode: Bulk tank, 28,000 lb a fill: about 1.6 deliveries a month, each fill lasting 19 days
06 Storage: Please quote both: a tank leased under a service agreement, and a per-pound price to fill a tank we own
07 Delivery: How refills are scheduled (from usage or fixed), remote level monitoring, the minimum delivery, and what happens if we run short
08 Documents: Certificate of analysis with each delivery; Statement that the product meets the ISBT guidelines and the CGA G-6.2 level
09 Price basis: Price per pound or per ton delivered, tank or cylinder rental, delivery charges, any surcharges, contract term
10 Use: Beverage carbonation or dispensing

Volumes are the buyer's stated use. Indicative arithmetic, not a quote.
```

## Recording it

POST the plan's `envelope` (included in plan.json) as JSON to https://millsheet.forevenza.com/raw-materials/requests?via=co2-supply. You get a reference number and your specification, ready to send to producers and distributors. We look at every requirement, and when we can source the grade to your delivery point or get it quoted, we reply to the email you leave. Nothing is ordered or committed until you agree terms. Contact details are kept apart from the requirement and deleted after 180 days.

Figures are indicative arithmetic from the inputs given, not a quote, a supplier or a delivery commitment.

## Sources

- Airgas, Converting Units of Measure for Gas (carbon dioxide table): https://newemarket.airgas.com/mcm-562.pdf
- Airgas, Food Grade Carbon Dioxide, 50 lb high-pressure cylinder: https://www.airgas.com/product/Gases/Carbon-Dioxide/p/CD%20FG50
- Airgas, Carbon Dioxide, 180 liter liquid cylinder (350 psi): https://www.airgas.com/product/Gases/Carbon-Dioxide/p/CD%20180LT350
- NuCO2, XactCO2 tank specifications; Chart Carbo series: https://www.nuco2.com/Product/XactCO2_1
- Chart Industries, Bulk CO2 Applications and Storage Systems: https://files.chartindustries.com/21111520_BulkCO2brochure_11x17.pdf
- Matheson, grade specifications for liquid carbon dioxide: https://www.mathesongas.com/wp-content/uploads/2022/05/Grade-Specifications-Liquid-Carbon-Dioxide.pdf
- ISBT, Bulk Carbon Dioxide: Quality and Food Safety Guidelines: https://www.isbt.com/resources/guidelines-best-practices-and-white-papers
- CGA G-6.2, Commodity Specification for Carbon Dioxide (7th edition, 2025): https://legacy.cganet.com/Publication/Details.aspx?id=G-6.2
- NuCO2, programs and pricing: https://www.nuco2.com/Customer/ProgramAndPrice
- Linde, beverage carbonation: https://www.lindeus.com/industries/food-and-beverage/beverage-carbonation
- City of Lompoc, published bid document for liquid carbon dioxide (water treatment): https://www.cityoflompoc.com/home/showpublisheddocument/45627/638864411054170000
- NSF, NSF/ANSI/CAN 60: Drinking Water Treatment Chemicals, Health Effects: https://www.nsf.org/knowledge-library/nsf-ansi-can-standard-60-drinking-water-treatment-chemicals-health-effects