The use of gas from a well producing gas only, or from a well which is primarily a gas well for the manufacture of carbon black or similar products predominantly carbon is declared to constitute waste prima facie, and the gas well may not be used for this purpose unless it is clearly shown at a public hearing held by the commission, on application of the person desiring to use the gas, that waste would not take place by the use of the gas for the purpose applied for, and that gas which would otherwise be lost is now available for such purpose, and that the gas to be used cannot be used for a more beneficial purpose, such as for light or fuel purposes, except at prohibitive cost, and that it would be in the public interest to grant the permit. If the commission finds that the applicant has clearly shown a right to use the gas for the purpose applied for, it shall issue a permit upon terms and conditions it finds necessary in order to permit the use of the gas and at the same time require compliance with the intent of this section.