Systems and methods for environmentally-clean thermal drying

A system for thermal drying, comprising:

• an indirect dryer configured to receive a bio-waste, to dry the bio-waste and generate a dried bio-waste, the dried bio-waste including a predetermined percentage of solids and uncleaned heated gases, the uncleaned heated gases including volatile organic compounds and particulate matter;
• a rotary kiln configured to receive the uncleaned heated gases from the indirect dryer to generate heat energy to incinerate the volatile organic compounds and the particulate matter to generate cleaned air, and wherein the cleaned air is exhausted from the rotary kiln;
• an ash cooling conveyor configured to indirectly cool ash created as a byproduct from the rotary kiln, the ash cooling conveyor configured to move the ash and indirectly cool the ash as the ash advances therethrough;
• and
• an oil circulating conduit connected with the rotary kiln and configured to house oil, wherein the heat energy from the rotary kiln is used to heat the oil, the oil circulating conduit including:
• an oil heat exchanger at a first end of the oil circulating conduit;
• an oil expansion tank arranged along a forward conduit path, the forward conduit path connecting the oil heat exchanger with the indirect dryer at a second end of the oil circulating conduit;
• and
• a return conduit path connecting the indirect dryer and the oil heat exchanger, wherein the return conduit path is unconnected with the oil expansion tank, wherein the heated oil is configured to be transferred along the return conduit path from the indirect dryer to the oil heat exchanger without passing the heated oil through the oil expansion tank.

A system for thermal drying, comprising:

• an indirect dryer configured to receive a bio-waste, to dry the bio-waste and generate a dried bio-waste, the dried bio-waste including a predetermined percentage of solids and uncleaned heated gases, the uncleaned heated gases including volatile organic compounds and particulate matter;
• a rotary kiln configured to receive the uncleaned heated gases from the indirect dryer to generate heat energy, wherein the heat energy is used in the rotary kiln to incinerate the volatile organic compounds and the particulate matter to generate cleaned air, and wherein the cleaned air is exhausted from the rotary kiln;
• a cooling conveyor operatively coupled to the indirect dryer, the cooling conveyor configured to transfer the dried bio-waste;
• a cool-water conduit loop coupled to the cooling conveyor configured to indirectly cool the dried bio-waste;
• and
• an oil circulating conduit connected with the rotary kiln configured to house oil, wherein the heat energy from the rotary kiln is used to heat the oil, the oil circulating conduit including:
• an oil heat exchanger at a first end of the oil circulating conduit;
• an oil expansion tank arranged along a forward conduit path, the forward conduit path connecting the oil heat exchanger with the indirect dryer at a second end of the oil circulating conduit;
• and
• a return conduit path connecting the indirect dryer and the oil heat exchanger, wherein the return conduit path is unconnected with the oil expansion tank, wherein the heated oil is configured to be transferred along the return conduit path from the indirect dryer to the oil heat exchanger without passing the heated oil through the oil expansion tank.